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30GB Hard Drive Camcorder: Editing Implications?
http://www.camcorderinfo.com/content/JVC-Introduces-Four-Hard-Drive-Based-Everio-Camcorders.htm The above write-up by Robin Liss says that, according to JVC, the 30GB Everio models can hold as much video as 22 DVD discs and the quality is just as good. JVC even placed their model next to a Sony DCR-DVD201 in a side by side video quality comparison. The new hard drive Everios record video in MPEG2 format, which is the standard used in DVD camcorders. I wondered if these new hard-drive-based camcorders would produce video with as good a quality as you can get from DV tapes? I guess 30GB is a lot of storage, equivalent to more than two 1-hour DV tapes, but if you do fill up your hard disk while you are walking in the hills, I suppose you would need a portable computer with you to download the video onto so that you could clear the hard drive? The advantage of tapes and DVDs is that you can have plenty of these with you if you are going to be a long time away from your computer in remote places! Does anyone know whether there would be any major problems in editing video from a camcorder with a hard drive? For example, would you be able to satisfactorily use a video editing program such as Vegas Video? Thanks for your comments. George S wrote:
> I see that JVC has introduced a 30GB hard drive camcorder, the Everio: http://www.camcorderinfo.com/content/JVC-Introduces-Four-Hard-Drive-Based-Everio-Camcorders.htm> > Show quoteHide quote > Did you catch the line in the review that said:> The above write-up by Robin Liss says that, according to JVC, > the 30GB Everio models can hold as much video as 22 DVD discs > and the quality is just as good. JVC even placed their model next to > a Sony DCR-DVD201 in a side by side video quality comparison. > The new hard drive Everios record video in MPEG2 format, which > is the standard used in DVD camcorders. > > I wondered if these new hard-drive-based camcorders would produce > video with as good a quality as you can get from DV tapes? I guess > 30GB is a lot of storage, equivalent to more than two 1-hour DV > tapes, but if you do fill up your hard disk while you are walking in > the hills, I suppose you would need a portable computer with you to > download > the video onto so that you could clear the hard drive? The advantage > of tapes and DVDs is that you can have plenty of these with you > if you are going to be a long time away from your computer in > remote places! Does anyone know whether there would be any > major problems in editing video from a camcorder with a hard drive? > For example, would you be able to satisfactorily use a video > editing program such as Vegas Video? Thanks for your comments. " While MPEG2 provides a lot of quality compression, and is the standard used in DVD camcorders, the structure makes it difficult to edit MPEG2 video without doing heavy conversion to another format. " Once again, the marketing side of things has taken precedence over the production side. Ask anyone who made the mistake of buying a DVD camcorder. Because of the MPEG2 recording format, It's difficult to edit because you can't cut on individual frames. Also, there's no mention of the audio format. If it's AC3, that's just as difficult as MPEG2. I'm not saying that it can't be done, just that it's going to make editing a lot more difficult. IMO, the picture quality will suffer as well as the MPEG2 compression being used will affect the overall quality. BTW, Vegas will have difficulties editing both MPEG2 and AC3 files. Read the various Vegas forums to discover this for yourself. Mike "Mike Kujbida" wrote ...
> Did you catch the line in the review that said: Hats back on, gentlemen. Anyone else not holding their breath?> " While MPEG2 provides a lot of quality compression, and is the > standard used in DVD camcorders, the structure makes it difficult > to edit MPEG2 video without doing heavy conversion to another > format. " > > Once again, the marketing side of things has taken precedence over > the production side. "Richard Crowley" <rcrowl***@xprt.net> writes: "Heavy conversion" just means it takes a lot of computating power to> > Did you catch the line in the review that said: > > " While MPEG2 provides a lot of quality compression, and is the > > standard used in DVD camcorders, the structure makes it difficult to > > edit MPEG2 video without doing heavy conversion to another format. " > > Once again, the marketing side of things has taken precedence over > > the production side. > > Hats back on, gentlemen. Anyone else not holding their breath? edit mpeg2. Fortunately, today's computers are very fast. "Paul Rubin" wrote...
Show quoteHide quote > "Richard Crowley" writes: The fastest computer can't recover the image detail that MPEG>> > Did you catch the line in the review that said: >> > " While MPEG2 provides a lot of quality compression, and is the >> > standard used in DVD camcorders, the structure makes it difficult >> > to >> > edit MPEG2 video without doing heavy conversion to another format. >> > " >> > Once again, the marketing side of things has taken precedence over >> > the production side. >> >> Hats back on, gentlemen. Anyone else not holding their breath? > > "Heavy conversion" just means it takes a lot of computating power to > edit mpeg2. Fortunately, today's computers are very fast. threw away at the first compression. On 15 Jun 2005 21:06:47 -0700, Paul Rubin
<http://phr.cx@NOSPAM.invalid> wrote: >"Heavy conversion" just means it takes a lot of computating power to Fast ain't the problem :)>edit mpeg2. Fortunately, today's computers are very fast. -martin- -- "Now I want you to say it thrice daily and don't dress a bun"
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"Paul Rubin" <http://phr.cx@NOSPAM.invalid> wrote in message No, it doesn't mean that. It means that an already over-compressed, lossynews:7x4qbzeyi0.fsf@ruckus.brouhaha.com... > "Richard Crowley" <rcrowl***@xprt.net> writes: > > > Did you catch the line in the review that said: > > > " While MPEG2 provides a lot of quality compression, and is the > > > standard used in DVD camcorders, the structure makes it difficult to > > > edit MPEG2 video without doing heavy conversion to another format. " > > > Once again, the marketing side of things has taken precedence over > > > the production side. > > > > Hats back on, gentlemen. Anyone else not holding their breath? > > "Heavy conversion" just means it takes a lot of computating power to > edit mpeg2. Fortunately, today's computers are very fast. format must first be transcoded to an editable format, resulting in more loss, and then re-transcoded back to mpeg, with yet more loss, for burning to DVD. If someone isn't interested in doing anything more than simple cuts-only editing, then the conversion step isn't necessary. However, for someone who wants to add transitions, titles, correction, effects, etc., there is no choice but to transcode to a format that is accepted by consumer/prosumer editing packages. Paul Rubin wrote:
Show quoteHide quote > "Richard Crowley" <rcrowl***@xprt.net> writes: Actually, no. MPEG compressions results in the loss of individual > >>>Did you catch the line in the review that said: >>>" While MPEG2 provides a lot of quality compression, and is the >>>standard used in DVD camcorders, the structure makes it difficult to >>>edit MPEG2 video without doing heavy conversion to another format. " >>>Once again, the marketing side of things has taken precedence over >>>the production side. >> >>Hats back on, gentlemen. Anyone else not holding their breath? > > > "Heavy conversion" just means it takes a lot of computating power to > edit mpeg2. Fortunately, today's computers are very fast. frames. There are key frames and interpolation between the frames. This makes frame accurate editing of MPEG compressed video impossible. You could decompress it, but since MPEG is lossy, you will not get the all the frames at the original quality and the timecode alignment of the audio and video frames will be slightly different each time you decompress. DV is also a lossy (4:2:2) compression scheme. However it preserves each frame. DVCAM goes a step further and locks the audio to the same frame based timecode as the video so there is no drift. > A MPEG 2 stream compressed with I frames only is identical to DV at the same> Actually, no. MPEG compressions results in the loss of individual > frames. There are key frames and interpolation between the frames. This > makes frame accurate editing of MPEG compressed video impossible. You > could decompress it, but since MPEG is lossy, you will not get the all > the frames at the original quality and the timecode alignment of the > audio and video frames will be slightly different each time you decompress. > > DV is also a lossy (4:2:2) compression scheme. However it preserves each > frame. DVCAM goes a step further and locks the audio to the same frame > based timecode as the video so there is no drift. bit-rate and of course ALL frames are there. Also DV is either 4:2:0 or 4:1:1 MPEG-2 can be 4:2:2 if using the 422P profile. Be careful when simply saying MPEG or MPEG-2 as it is a huge generalisation. You have to be specific e.g. HDV uses MPEG-2 25 Mbps (MP @ H-14) and for the really high end 300Mbps (422P @ HL) which supports 1980x1080 and is a theoretical match for HDCAM. Not everything that glitters is gold... Specs wrote:
Show quoteHide quote >>Actually, no. MPEG compressions results in the loss of individual Right about the 4:1:1. Oops.>>frames. There are key frames and interpolation between the frames. This >>makes frame accurate editing of MPEG compressed video impossible. You >>could decompress it, but since MPEG is lossy, you will not get the all >>the frames at the original quality and the timecode alignment of the >>audio and video frames will be slightly different each time you > > decompress. > >>DV is also a lossy (4:2:2) compression scheme. However it preserves each >>frame. DVCAM goes a step further and locks the audio to the same frame >>based timecode as the video so there is no drift. > > > A MPEG 2 stream compressed with I frames only is identical to DV at the same > bit-rate and of course ALL frames are there. Also DV is either 4:2:0 or > 4:1:1 MPEG-2 can be 4:2:2 if using the 422P profile. > > Be careful when simply saying MPEG or MPEG-2 as it is a huge generalisation. > You have to be specific e.g. HDV uses MPEG-2 25 Mbps (MP @ H-14) and for the > really high end 300Mbps (422P @ HL) which supports 1980x1080 and is a > theoretical match for HDCAM. > > Not everything that glitters is gold... > > But regarding MPEG, I thought the MPEG-2 in DVD's and in this particular camcorder was made up of key frames, differnce data and interpolation - so that not every frame was compressed. Also, is an compressed MPEG 2 stream with only I frames lossy on non-lossy compression? Check out www.womble.com for their very useful MPEG2 editor. I use it
for the MPEG2 video I get from my Panasonic SV-AV100. It's not Avid Xpress DV, but great for the home auteur. Bye. "George S" <George S@enquiry.org> writes: There's nothing special about the DV format. Just because it uses a> I wondered if these new hard-drive-based camcorders would produce > video with as good a quality as you can get from DV tapes? lower compression ratio than mpeg-2 doesn't mean the quality is better. It just means it's an older standard from an era when less processing power was available. Today's prosumer HDTV camcorders use mpeg-like compression schemes to record 1080-line HDTV at the same bit rate as mini-DV. I think most people will say that the HDTV video, displayed on a high res monitor, beats the pants of regular mini-DV in image quality.
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"Paul Rubin" <http://phr.cx@NOSPAM.invalid> wrote in message Thanks for the interesting replies. The article says that with a bitrate ofnews:7x7jgv0z4m.fsf@ruckus.brouhaha.com... > "George S" <George S@enquiry.org> writes: >> I wondered if these new hard-drive-based camcorders would produce >> video with as good a quality as you can get from DV tapes? > > There's nothing special about the DV format. Just because it uses a > lower compression ratio than mpeg-2 doesn't mean the quality is > better. It just means it's an older standard from an era when less > processing power was available. Today's prosumer HDTV camcorders use > mpeg-like compression schemes to record 1080-line HDTV at the same bit > rate as mini-DV. I think most people will say that the HDTV video, > displayed on a high res monitor, beats the pants of regular mini-DV in > image quality. 9Mbps, you get 7 hours of recording with the models that have the 30-gig hard drives: JVC GZ-MG50 and GZ-MG30. I wonder what the bitrate would be for the best quality you can get on consumer level DV tapes? In other words, could you get quality that is good as DV tape from a 9Mbps recording on a hard drive? In any event, why can't you record the miniDV tape format on a hard drive because you do this in effect when you capture from a DV tape to a hard drive. A JVC hard drive camcorder doesn't have to use MPEG2 does it? Another point, even after editing DV tape through a program such as Sony Vegas Video, if you transfer the result to a DVD (which most people would do rather than back to DV tape) then you have effectively compressed the video to the MPEG format anyway! Regards, George "George S" <George S@enquiry.org> writes: Well, you can't directly compare, since it's difficult to quantify> Thanks for the interesting replies. The article says that with a bitrate of > 9Mbps, you get 7 hours of recording with the models that have the > 30-gig hard drives: JVC GZ-MG50 and GZ-MG30. I wonder what > the bitrate would be for the best quality you can get on consumer level > DV tapes? In other words, could you get quality that is good as DV > tape from a 9Mbps recording on a hard drive? "good", and mpeg will always beat dv at some things and lose to it at others. I'd say that with these consumer cameras, including fairly expensive ones, the quality will be determined by the lens and ccd, and the compression format is a minor issue. Only at the VX2000 level will compression artifacts start to predominate. > In any event, why can't you record the miniDV tape format on a hard It could record in DV format but would need over 10 GB an hour.> drive because you do this in effect when you capture from a DV tape > to a hard drive. A JVC hard drive camcorder doesn't have to use > MPEG2 does it? > Another point, even after editing DV tape through a program such as Yes, but you don't do that compression til the end of the process, one> Sony Vegas Video, if you transfer the result to a DVD (which most > people would do rather than back to DV tape) then you have > effectively compressed the video to the MPEG format anyway! hopes.
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"George S" <George S@enquiry.org> wrote in message Absolutely not. 9 mbps is roughly equivalent to the maximum bit rate fornews:42b1178b$1@clear.net.nz... > > "Paul Rubin" <http://phr.cx@NOSPAM.invalid> wrote in message > news:7x7jgv0z4m.fsf@ruckus.brouhaha.com... > > "George S" <George S@enquiry.org> writes: > >> I wondered if these new hard-drive-based camcorders would produce > >> video with as good a quality as you can get from DV tapes? > > > > There's nothing special about the DV format. Just because it uses a > > lower compression ratio than mpeg-2 doesn't mean the quality is > > better. It just means it's an older standard from an era when less > > processing power was available. Today's prosumer HDTV camcorders use > > mpeg-like compression schemes to record 1080-line HDTV at the same bit > > rate as mini-DV. I think most people will say that the HDTV video, > > displayed on a high res monitor, beats the pants of regular mini-DV in > > image quality. > > Thanks for the interesting replies. The article says that with a bitrate of > 9Mbps, you get 7 hours of recording with the models that have the > 30-gig hard drives: JVC GZ-MG50 and GZ-MG30. I wonder what > the bitrate would be for the best quality you can get on consumer level > DV tapes? In other words, could you get quality that is good as DV > tape from a 9Mbps recording on a hard drive? DVD. DV-25, e.g. miniDV, Digital8 and DV-CAM is 25 mbps, or nearly 3 times as much. Another way to look at it is, this new toy camera throws away 3 times as much picture detail as a miniDV camera. Remember this, too: Bit rate is, literally, only part of the picture. Optics and electronics make up the rest. Toy cameras like these do not have good optics, and tend to use tiny CCD sensors, which have dismal low-light performance. If there's any question that this is intended to be a toy camera, note that it transfers video via USB. USB can, of course, transfer full-resolution video (in theory). However, the standard for video transfer is OHCI-compliant 1394/Firewire. There's nothing wrong with the concept of a hard-drive based camera. There's plenty wrong with this implementation. > In any event, why Yes. However, you're capturing 300% more detail with miniDV than with this> can't you record the miniDV tape format on a hard drive because > you do this in effect when you capture from a DV tape to a hard drive. > A JVC hard drive camcorder doesn't have to use MPEG2 does it? camera's mpeg2 compression, even at the highest resolution available to the camera. > That's correct. However, the better software transcoders will always do a> Another point, even after editing DV tape through a program such > as Sony Vegas Video, if you transfer the result to a DVD (which > most people would do rather than back to DV tape) then you > have effectively compressed the video to the MPEG format > anyway! better job than on-the-fly consumer grade hardware transcoders, such as are in this camera. The best mpeg transcoding requires more than one pass through the material. Realtime mpeg conversion can only be single-pass. Note, too, that, unless you plan on doing only minimal cuts-only editing, you'll have to convert the camera's mpeg to something more universally compatible. You will not be able to easily edit the output of this camera in Vegas or Premiere, and definitely not in the lower-range consumer editors such as Studio. Show quoteHide quote > > Regards, George > > "PTravel" <ptra***@ruyitang.com> writes: I dunno about DVD but ISTR that the micro-MV cameras record mpeg-2 at> Absolutely not. 9 mbps is roughly equivalent to the maximum bit rate for > DVD. about 12 mbps. > DV-25, e.g. miniDV, Digital8 and DV-CAM is 25 mbps, or nearly 3 times That's silly, it's like saying that 300 kbit MP3 throws away 5x as> as much. Another way to look at it is, this new toy camera throws away 3 > times as much picture detail as a miniDV camera. much audio detail as 1.5 mbit PCM. The most you can really say is that if you compare a 300 kbit mp3 recording to a 16/44 WAV from the same original, you might be able to detect difference here or there. It's not even certain that the mp3 will sound "worse" than the 16/44 wav, if the original is, say, a 24/192 recording. "Paul Rubin" <http://phr.cx@NOSPAM.invalid> wrote in message This is what you wrote to which I was responding:news:7xll5adw8v.fsf@ruckus.brouhaha.com... > "PTravel" <ptra***@ruyitang.com> writes: > > Absolutely not. 9 mbps is roughly equivalent to the maximum bit rate for > > DVD. > > I dunno about DVD but ISTR that the micro-MV cameras record mpeg-2 at > about 12 mbps. "There's nothing special about the DV format. Just because it uses a lower compression ratio than mpeg-2 doesn't mean the quality is better." We're not talking about Micro-MV, which is another toy format. > PCM is not lossy, versus MP3, which is. That's apples and oranges. We're> > DV-25, e.g. miniDV, Digital8 and DV-CAM is 25 mbps, or nearly 3 times > > as much. Another way to look at it is, this new toy camera throws away 3 > > times as much picture detail as a miniDV camera. > > That's silly, it's like saying that 300 kbit MP3 throws away 5x as > much audio detail as 1.5 mbit PCM. comparing mpeg and DV-25, both of which are lossy compression formats. DVD mpeg compresses at least 3 times as much as DV-25, resulting in 3x as much loss of detail. > The most you can really say is We're not talking about audio formats, but video. As I said in another> that if you compare a 300 kbit mp3 recording to a 16/44 WAV from the > same original, you might be able to detect difference here or there. > It's not even certain that the mp3 will sound "worse" than the 16/44 > wav, if the original is, say, a 24/192 recording. post, if you can't see the difference between mpeg compression and DV-25, then you need a better television, or should get your eyes checked. This is what you said: "[B]ecause [DV-25] uses a lower compression ratio than mpeg-2 doesn't mean the quality is better." The statement is incorrect. On Thu, 16 Jun 2005 11:42:52 -0700, "PTravel" <ptra***@ruyitang.com> Not necessarily. MPEG2 is a different form of compression, because itwrote: >DVD mpeg compresses at least 3 times as much as DV-25, resulting in 3x as much >loss of detail. uses _one_ master-frame, and then a saves a bunch of data showing only the difference between those frames. With DV25 you save whole frames all the time, meaning that in the end you have much more data left. MPEG2 is a better codec then DV25, when it comes to similar data-rates from similar sources (SD) [as my buddy Specs also mentioned]. And to get this good quality, you need a good encoder, and know how to tweak the parameters, to get the best results. Let's say, a static shot of a vase would look good already on 2.5 Mbps, while for a moving shot you need to go higher to, say 8 Mbps. cheers -martin- -- "Now I want you to say it thrice daily and don't dress a bun"
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"Martin Heffels" <mana***@usg-managers.com> wrote in message I don't know what you're referencing by SD. Do you mean standard definitionnews:21j3b1pmvuca8t3pd00uepq6i22h2ne3i5@4ax.com... > On Thu, 16 Jun 2005 11:42:52 -0700, "PTravel" <ptra***@ruyitang.com> > wrote: > > >DVD mpeg compresses at least 3 times as much as DV-25, resulting in 3x as much > >loss of detail. > > Not necessarily. MPEG2 is a different form of compression, because it > uses _one_ master-frame, and then a saves a bunch of data showing only > the difference between those frames. With DV25 you save whole frames > all the time, meaning that in the end you have much more data left. > > MPEG2 is a better codec then DV25, when it comes to similar data-rates > from similar sources (SD) [as my buddy Specs also mentioned]. video? If so, mpeg2 is most decidely NOT a better codec, at least not for moving images. > And to You don't honestly think this discussion is about static shots of vases, do> get this good quality, you need a good encoder, and know how to tweak > the parameters, to get the best results. Let's say, a static shot of > a vase would look good already on 2.5 Mbps, while for a moving shot > you need to go higher to, say 8 Mbps. you? That's like saying both formats are equal if you are showing a picture of detail-less blue wall. Video moves and, particularly, with respect to miniDV, moves a lot. Mpeg2 has higher compression rates and, therefore, loses more detail (far more detail) than miniDV. Show quoteHide quote > > cheers > > -martin- > > -- > "Now I want you to say it thrice daily and don't dress a bun" On Thu, 16 Jun 2005 13:00:53 -0700, "PTravel" <ptra***@ruyitang.com> Yes, standard definition.wrote: >I don't know what you're referencing by SD. Do you mean standard definition >video? >If so, mpeg2 is most decidely NOT a better codec, at least not for In the SMPTE-magazine was an article (I think 2003) where they did a>moving images. scientific test on how much an image was altered after compression and then decompressed again. MPEG2 came out with less difference than DV25 at the same datarate. >You don't honestly think this discussion is about static shots of vases, do No. I am talking about how tuning of the compression, gets you a>you? better picture. The vase was a mere example of an image where a higher compression leads to less problems than high compression of a moving object. >Video moves and, particularly, with respect to Again, that depends on how you use the codec.>miniDV, moves a lot. Mpeg2 has higher compression rates and, therefore, >loses more detail (far more detail) than miniDV. cheers -martin- -- "Now I want you to say it thrice daily and don't dress a bun"
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"Martin Heffels" <mana***@usg-managers.com> wrote in message Everything depends on the image, though. For images with a lot of movement,news:uun3b1dm27r86fomcrk9nnkjcet0fdnjnc@4ax.com... > On Thu, 16 Jun 2005 13:00:53 -0700, "PTravel" <ptra***@ruyitang.com> > wrote: > > >I don't know what you're referencing by SD. Do you mean standard definition > >video? > > Yes, standard definition. > > >If so, mpeg2 is most decidely NOT a better codec, at least not for > >moving images. > > In the SMPTE-magazine was an article (I think 2003) where they did a > scientific test on how much an image was altered after compression and > then decompressed again. MPEG2 came out with less difference than DV25 > at the same datarate. mpeg2 will drop far more data than DV25. > Well, I'm talking about the camcorder which is the subject of this thread.> > >You don't honestly think this discussion is about static shots of vases, do > >you? > > No. I am talking about how tuning of the compression, gets you a > better picture. The vase was a mere example of an image where a higher > compression leads to less problems than high compression of a moving > object. It's a video camera for consumers and will not be used to take static shots of vases. It's intended for the same subject matter as other consumer camcorders, i.e. moving, chaotic images. It does single-pass, on-the-fly mpeg encoding. It will not produce video as detailed as a miniDV camcorder. > I'm not sure what you mean by how you use the codec. DVD-complaint mpeg> >Video moves and, particularly, with respect to > >miniDV, moves a lot. Mpeg2 has higher compression rates and, therefore, > >loses more detail (far more detail) than miniDV. > > Again, that depends on how you use the codec. tops out at around 10 mbps. I transcode using tmpgenc and tweak the mpeg, within DVD spec requirements, quite a bit and get extremely good results. They are not, however, anywhere near as detailed as the DV25 source. Show quoteHide quote > > cheers > > -martin- > > -- > "Now I want you to say it thrice daily and don't dress a bun" On Thu, 16 Jun 2005 14:34:38 -0700, "PTravel" <ptra***@ruyitang.com> That's what I'm saying all the time already. But at higher datarates,wrote: >Everything depends on the image, though. For images with a lot of movement, >mpeg2 will drop far more data than DV25. comparable to DV25, MPEG2 does better than DV25 (providing the source of origin is standard video, 720x576 if you're in PAL, and you know the numbers for NTSC). >Well, I'm talking about the camcorder which is the subject of this thread. Yes, for that camcorder, with a data-rate of 9MB/s, it's going to>It's a video camera for consumers and will not be used to take static shots >of vases. It's intended for the same subject matter as other consumer >camcorders, i.e. moving, chaotic images. It does single-pass, on-the-fly >mpeg encoding. It will not produce video as detailed as a miniDV camcorder. become difficult, I agree. >> >Video moves and, particularly, with respect to Sorry, I meant to say, coder (or encoder), and not codec. The quality>> >miniDV, moves a lot. Mpeg2 has higher compression rates and, therefore, >> >loses more detail (far more detail) than miniDV. >> >> Again, that depends on how you use the codec. > >I'm not sure what you mean by how you use the codec. DVD-complaint mpeg >tops out at around 10 mbps. I transcode using tmpgenc and tweak the mpeg, >within DVD spec requirements, quite a bit and get extremely good results. >They are not, however, anywhere near as detailed as the DV25 source. of the encoder determines the final quality of the picture. A commercial DVD, encoded with a US$25000+ hardware encoder, will look better than a Procoder encoded one (one of the better encoders). And like you said, good quality requires tweaking (datarate, keyframes, GOP's etc) to get the best result. cheers -martin- -- "Now I want you to say it thrice daily and don't dress a bun"
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"PTravel" <ptra***@ruyitang.com> wrote in message My very good friend Martin was trying to give you a very simple example tonews:3he43nFgo1muU1@individual.net... > > "Martin Heffels" <mana***@usg-managers.com> wrote in message > news:21j3b1pmvuca8t3pd00uepq6i22h2ne3i5@4ax.com... > > On Thu, 16 Jun 2005 11:42:52 -0700, "PTravel" <ptra***@ruyitang.com> > > wrote: > > > > >DVD mpeg compresses at least 3 times as much as DV-25, resulting in 3x as > much > > >loss of detail. > > > > Not necessarily. MPEG2 is a different form of compression, because it > > uses _one_ master-frame, and then a saves a bunch of data showing only > > the difference between those frames. With DV25 you save whole frames > > all the time, meaning that in the end you have much more data left. > > > > MPEG2 is a better codec then DV25, when it comes to similar data-rates > > from similar sources (SD) [as my buddy Specs also mentioned]. > > I don't know what you're referencing by SD. Do you mean standard definition > video? If so, mpeg2 is most decidely NOT a better codec, at least not for > moving images. > > > And to > > get this good quality, you need a good encoder, and know how to tweak > > the parameters, to get the best results. Let's say, a static shot of > > a vase would look good already on 2.5 Mbps, while for a moving shot > > you need to go higher to, say 8 Mbps. > > You don't honestly think this discussion is about static shots of vases, do > you? That's like saying both formats are equal if you are showing a picture > of detail-less blue wall. Video moves and, particularly, with respect to > miniDV, moves a lot. Mpeg2 has higher compression rates and, therefore, > loses more detail (far more detail) than miniDV. > aid your understanding of the merits of MPEG2 compression. Clearly you misunderstood. MPEG2 is a more efficient codec than DV25. As we know DV25 is, er, a 25Mbps SD stream. If one were to shoot a 25 Mbps MPEG2 SD stream it would give a superior image to the DV25 image. MPEG2 gets a bad rap because most people only ever see low bit rate versions on DVD, Sat or Cable. MPEG2 is going to be around for a while with HDV, XDCAM and XDCAM HD coming early next year. The two Sony XDCAM HD are expected to support 4:2:0 VBR long GOP at 36 Mbps and the more expensive version 4:2:2 VBR long GOP at 72 Mbps. Both will record 1440x1080i. I don't know about 24p yet. It should also be pointed MPEG2 has various Profiles and Levels which can drastically change the quality of the image.
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"Specs" <No.Spam@Thanks.com> wrote in message On the contrary, I understand perfectly. You and your "very good friend"news:42b1e8f4$0$2422$ed2619ec@ptn-nntp-reader02.plus.net... > > "PTravel" <ptra***@ruyitang.com> wrote in message > news:3he43nFgo1muU1@individual.net... > > > > "Martin Heffels" <mana***@usg-managers.com> wrote in message > > news:21j3b1pmvuca8t3pd00uepq6i22h2ne3i5@4ax.com... > > > On Thu, 16 Jun 2005 11:42:52 -0700, "PTravel" <ptra***@ruyitang.com> > > > wrote: > > > > > > >DVD mpeg compresses at least 3 times as much as DV-25, resulting in 3x > as > > much > > > >loss of detail. > > > > > > Not necessarily. MPEG2 is a different form of compression, because it > > > uses _one_ master-frame, and then a saves a bunch of data showing only > > > the difference between those frames. With DV25 you save whole frames > > > all the time, meaning that in the end you have much more data left. > > > > > > MPEG2 is a better codec then DV25, when it comes to similar data-rates > > > from similar sources (SD) [as my buddy Specs also mentioned]. > > > > I don't know what you're referencing by SD. Do you mean standard > definition > > video? If so, mpeg2 is most decidely NOT a better codec, at least not for > > moving images. > > > > > And to > > > get this good quality, you need a good encoder, and know how to tweak > > > the parameters, to get the best results. Let's say, a static shot of > > > a vase would look good already on 2.5 Mbps, while for a moving shot > > > you need to go higher to, say 8 Mbps. > > > > You don't honestly think this discussion is about static shots of vases, > do > > you? That's like saying both formats are equal if you are showing a > picture > > of detail-less blue wall. Video moves and, particularly, with respect to > > miniDV, moves a lot. Mpeg2 has higher compression rates and, therefore, > > loses more detail (far more detail) than miniDV. > > > My very good friend Martin was trying to give you a very simple example to > aid your understanding of the merits of MPEG2 compression. Clearly you > misunderstood. have trouble staying on topic. Read the thread header. This is not a discussion about the theoretical limits of mpeg, but about (1) a consumer mpeg-based camcorder, and (2) DVD-compliant mpeg, both of which are being used in the real world of moving images, not test still life. > Perhaps so. DVD-compliant mpeg tops out around 10 mbps, so your point is> MPEG2 is a more efficient codec than DV25. As we know DV25 is, er, a 25Mbps > SD stream. If one were to shoot a 25 Mbps MPEG2 SD stream it would give a > superior image to the DV25 image. completely irrelevant. > MPEG2 gets a bad rap because most people We are talking about mpeg2 in the context of DVD, only. If you want to have> only ever see low bit rate versions on DVD, Sat or Cable. a discussion about theoretical efficiencies at non-standard bit rates, start another thread. > See above. Not relevant in the least tot his discussion.> MPEG2 is going to be around for a while with HDV, XDCAM and XDCAM HD coming > early next year. The two Sony XDCAM HD are expected to support 4:2:0 VBR > long GOP at 36 Mbps and the more expensive version 4:2:2 VBR long GOP at 72 > Mbps. Both will record 1440x1080i. I don't know about 24p yet. > > It should also be pointed MPEG2 has various Profiles and Levels which can > drastically change the quality of the image. Show quoteHide quote > > On Thu, 16 Jun 2005 14:37:55 -0700, "PTravel" <ptra***@ruyitang.com> So, if you would be able to create a DV-9 encoded file, it would lookwrote: >This is not a >discussion about the theoretical limits of mpeg, but about (1) a consumer >mpeg-based camcorder, and (2) DVD-compliant mpeg, both of which are being >used in the real world of moving images, not test still life. worse than a MPEG-2 at 9 Mbps (to go back on topic). >Perhaps so. DVD-compliant mpeg tops out around 10 mbps, so your point is In the case of DVD's it is, but MPEG2 is not limited to 10 Mbps.>completely irrelevant. > Threads jump all the way, all the time. You are here long enough to>> MPEG2 gets a bad rap because most people >> only ever see low bit rate versions on DVD, Sat or Cable. > >We are talking about mpeg2 in the context of DVD, only. If you want to have >a discussion about theoretical efficiencies at non-standard bit rates, start >another thread. know this :) cheers -martin- -- "Now I want you to say it thrice daily and don't dress a bun"
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"PTravel" <ptra***@ruyitang.com> wrote in message You should't write crap like this,news:3he9pkFgocoiU1@individual.net... > > "Specs" <No.Spam@Thanks.com> wrote in message > news:42b1e8f4$0$2422$ed2619ec@ptn-nntp-reader02.plus.net... > > > > "PTravel" <ptra***@ruyitang.com> wrote in message > > news:3he43nFgo1muU1@individual.net... > > > > > > "Martin Heffels" <mana***@usg-managers.com> wrote in message > > > news:21j3b1pmvuca8t3pd00uepq6i22h2ne3i5@4ax.com... > > > > On Thu, 16 Jun 2005 11:42:52 -0700, "PTravel" <ptra***@ruyitang.com> > > > > wrote: > > > > > > > > >DVD mpeg compresses at least 3 times as much as DV-25, resulting in > 3x > > as > > > much > > > > >loss of detail. > > > > > > > > Not necessarily. MPEG2 is a different form of compression, because it > > > > uses _one_ master-frame, and then a saves a bunch of data showing only > > > > the difference between those frames. With DV25 you save whole frames > > > > all the time, meaning that in the end you have much more data left. > > > > > > > > MPEG2 is a better codec then DV25, when it comes to similar data-rates > > > > from similar sources (SD) [as my buddy Specs also mentioned]. > > > > > > I don't know what you're referencing by SD. Do you mean standard > > definition > > > video? If so, mpeg2 is most decidely NOT a better codec, at least not > for > > > moving images. > > > > > > > And to > > > > get this good quality, you need a good encoder, and know how to tweak > > > > the parameters, to get the best results. Let's say, a static shot of > > > > a vase would look good already on 2.5 Mbps, while for a moving shot > > > > you need to go higher to, say 8 Mbps. > > > > > > You don't honestly think this discussion is about static shots of vases, > > do > > > you? That's like saying both formats are equal if you are showing a > > picture > > > of detail-less blue wall. Video moves and, particularly, with respect > to > > > miniDV, moves a lot. Mpeg2 has higher compression rates and, therefore, > > > loses more detail (far more detail) than miniDV. > > > > > My very good friend Martin was trying to give you a very simple example to > > aid your understanding of the merits of MPEG2 compression. Clearly you > > misunderstood. > > On the contrary, I understand perfectly. You and your "very good friend" > have trouble staying on topic. Read the thread header. This is not a > discussion about the theoretical limits of mpeg, but about (1) a consumer > mpeg-based camcorder, and (2) DVD-compliant mpeg, both of which are being > used in the real world of moving images, not test still life. > > > > > MPEG2 is a more efficient codec than DV25. As we know DV25 is, er, a > 25Mbps > > SD stream. If one were to shoot a 25 Mbps MPEG2 SD stream it would give a > > superior image to the DV25 image. > > Perhaps so. DVD-compliant mpeg tops out around 10 mbps, so your point is > completely irrelevant. > > > MPEG2 gets a bad rap because most people > > only ever see low bit rate versions on DVD, Sat or Cable. > > We are talking about mpeg2 in the context of DVD, only. If you want to have > a discussion about theoretical efficiencies at non-standard bit rates, start > another thread. > > > > > MPEG2 is going to be around for a while with HDV, XDCAM and XDCAM HD > coming > > early next year. The two Sony XDCAM HD are expected to support 4:2:0 VBR > > long GOP at 36 Mbps and the more expensive version 4:2:2 VBR long GOP at > 72 > > Mbps. Both will record 1440x1080i. I don't know about 24p yet. > > > > It should also be pointed MPEG2 has various Profiles and Levels which can > > drastically change the quality of the image. > > See above. Not relevant in the least tot his discussion. > > > > > > "MiniDV is a video format, i.e. not used for static shots, and that was the basis for the original comparison. Yes, mpeg and DV-25 use different compression formats. And for virtually all video uses, e.g. excluding static slide shows and the like, DV-25 is going to display more detail than mpeg." And this, "I don't know what you're referencing by SD. Do you mean standard definition video? If so, mpeg2 is most decidely NOT a better codec, at least not for moving images." And this, "Hunh? Of course it does. Both DV-25 and mpeg are lossy compression formats. However, DV-25 results in about 5-to-1 compression, whereas mpeg is another order of magnitude greater." And not expect to be re-educated... Goodnight.
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"Specs" <No.Spam@Thanks.com> wrote in message <ptra***@ruyitang.com>news:42b1ff89$0$2421$ed2619ec@ptn-nntp-reader02.plus.net... > > "PTravel" <ptra***@ruyitang.com> wrote in message > news:3he9pkFgocoiU1@individual.net... > > > > "Specs" <No.Spam@Thanks.com> wrote in message > > news:42b1e8f4$0$2422$ed2619ec@ptn-nntp-reader02.plus.net... > > > > > > "PTravel" <ptra***@ruyitang.com> wrote in message > > > news:3he43nFgo1muU1@individual.net... > > > > > > > > "Martin Heffels" <mana***@usg-managers.com> wrote in message > > > > news:21j3b1pmvuca8t3pd00uepq6i22h2ne3i5@4ax.com... > > > > > On Thu, 16 Jun 2005 11:42:52 -0700, "PTravel" Show quoteHide quote > > > > > wrote: You are simply one of those posters who thrives on trying to prove others> > > > > > > > > > >DVD mpeg compresses at least 3 times as much as DV-25, resulting in > > 3x > > > as > > > > much > > > > > >loss of detail. > > > > > > > > > > Not necessarily. MPEG2 is a different form of compression, because > it > > > > > uses _one_ master-frame, and then a saves a bunch of data showing > only > > > > > the difference between those frames. With DV25 you save whole frames > > > > > all the time, meaning that in the end you have much more data left. > > > > > > > > > > MPEG2 is a better codec then DV25, when it comes to similar > data-rates > > > > > from similar sources (SD) [as my buddy Specs also mentioned]. > > > > > > > > I don't know what you're referencing by SD. Do you mean standard > > > definition > > > > video? If so, mpeg2 is most decidely NOT a better codec, at least not > > for > > > > moving images. > > > > > > > > > And to > > > > > get this good quality, you need a good encoder, and know how to > tweak > > > > > the parameters, to get the best results. Let's say, a static shot of > > > > > a vase would look good already on 2.5 Mbps, while for a moving shot > > > > > you need to go higher to, say 8 Mbps. > > > > > > > > You don't honestly think this discussion is about static shots of > vases, > > > do > > > > you? That's like saying both formats are equal if you are showing a > > > picture > > > > of detail-less blue wall. Video moves and, particularly, with respect > > to > > > > miniDV, moves a lot. Mpeg2 has higher compression rates and, > therefore, > > > > loses more detail (far more detail) than miniDV. > > > > > > > My very good friend Martin was trying to give you a very simple example > to > > > aid your understanding of the merits of MPEG2 compression. Clearly you > > > misunderstood. > > > > On the contrary, I understand perfectly. You and your "very good friend" > > have trouble staying on topic. Read the thread header. This is not a > > discussion about the theoretical limits of mpeg, but about (1) a consumer > > mpeg-based camcorder, and (2) DVD-compliant mpeg, both of which are being > > used in the real world of moving images, not test still life. > > > > > > > > MPEG2 is a more efficient codec than DV25. As we know DV25 is, er, a > > 25Mbps > > > SD stream. If one were to shoot a 25 Mbps MPEG2 SD stream it would give > a > > > superior image to the DV25 image. > > > > Perhaps so. DVD-compliant mpeg tops out around 10 mbps, so your point is > > completely irrelevant. > > > > > MPEG2 gets a bad rap because most people > > > only ever see low bit rate versions on DVD, Sat or Cable. > > > > We are talking about mpeg2 in the context of DVD, only. If you want to > have > > a discussion about theoretical efficiencies at non-standard bit rates, > start > > another thread. > > > > > > > > MPEG2 is going to be around for a while with HDV, XDCAM and XDCAM HD > > coming > > > early next year. The two Sony XDCAM HD are expected to support 4:2:0 > VBR > > > long GOP at 36 Mbps and the more expensive version 4:2:2 VBR long GOP at > > 72 > > > Mbps. Both will record 1440x1080i. I don't know about 24p yet. > > > > > > It should also be pointed MPEG2 has various Profiles and Levels which > can > > > drastically change the quality of the image. > > > > See above. Not relevant in the least tot his discussion. > > > > > > > > > > > You should't write crap like this, > > "MiniDV is a video format, i.e. not used for static shots, and that was the > basis for the original comparison. Yes, mpeg and DV-25 use different > compression formats. And for virtually all video uses, e.g. excluding > static slide shows and the like, DV-25 is going to display more detail than > mpeg." > > And this, > > "I don't know what you're referencing by SD. Do you mean standard > definition > video? If so, mpeg2 is most decidely NOT a better codec, at least not for > moving images." > > And this, > > "Hunh? Of course it does. Both DV-25 and mpeg are lossy compression > formats. However, DV-25 results in about 5-to-1 compression, whereas mpeg > is another order of magnitude greater." > > And not expect to be re-educated... > > Goodnight. wrong and, worse, simply won't admit when you're wrong. Go off to the sand box and play with your "very good friend." We're discussing video, here. Show quoteHide quote > > "PTravel" <ptra***@ruyitang.com> writes: MicroMV uses mpeg-2.> "There's nothing special about the DV format. Just because it uses a > lower compression ratio than mpeg-2 doesn't mean the quality is > better." > > We're not talking about Micro-MV, which is another toy format. > PCM is not lossy, versus MP3, which is. That's apples and oranges. We're Irrelevant. For example, 128 kbit MP4 (AAC) sounds better than 160 kbit> comparing mpeg and DV-25, both of which are lossy compression formats. MP3. Both are lossy. > DVD mpeg compresses at least 3 times as much as DV-25, resulting in That's plain bogus.> 3x as much loss of detail. > We're not talking about audio formats, but video. As I said in another Except for some special pathological cases (someone mentioned fast pans),> post, if you can't see the difference between mpeg compression and DV-25, > then you need a better television, or should get your eyes checked. almost everyone agrees that HDV (mpeg) looks better than mini-DV at the same bit rate. If you want to compare 4 megabit mpeg2 to dv25, that's one thing. But Mpeg is a variable bit rate compressor. > "[B]ecause [DV-25] uses a lower compression ratio than mpeg-2 doesn't mean False, see the HDV vs Mini-DV example. Now imagine HDV at 24.5 mbits> the quality is better." > > The statement is incorrect. vs Mini-DV at 25 mbits. Do you think HDV will fall apart because of using 2% more compression? "Paul Rubin" <http://phr.cx@NOSPAM.invalid> wrote in message So what? Read the the subject line.news:7xmzppx3um.fsf@ruckus.brouhaha.com... > "PTravel" <ptra***@ruyitang.com> writes: > > "There's nothing special about the DV format. Just because it uses a > > lower compression ratio than mpeg-2 doesn't mean the quality is > > better." > > > > We're not talking about Micro-MV, which is another toy format. > > MicroMV uses mpeg-2. > Okay, try to focus: we were talking about an mpeg2-using hard-drive> > PCM is not lossy, versus MP3, which is. That's apples and oranges. We're > > comparing mpeg and DV-25, both of which are lossy compression formats. > > Irrelevant. For example, 128 kbit MP4 (AAC) sounds better than 160 kbit > MP3. Both are lossy. camcorder versus miniDV. You want to talk about audio? Go to a different newsgroup, or at least start a new thread. Show quoteHide quote > One more time: we're not talking about mpeg-encoded HDV, but about the> > DVD mpeg compresses at least 3 times as much as DV-25, resulting in > > 3x as much loss of detail. > > That's plain bogus. > > > We're not talking about audio formats, but video. As I said in another > > post, if you can't see the difference between mpeg compression and DV-25, > > then you need a better television, or should get your eyes checked. > > Except for some special pathological cases (someone mentioned fast pans), > almost everyone agrees that HDV (mpeg) looks better than mini-DV at the > same bit rate. comparision between the 30 GB hard drive camcorder in the subject line and miniDV. > If you want to compare 4 megabit mpeg2 to dv25, that's Doesn't matter. Read the subject line.> one thing. But Mpeg is a variable bit rate compressor. Show quoteHide quote > > > "[B]ecause [DV-25] uses a lower compression ratio than mpeg-2 doesn't mean > > the quality is better." > > > > The statement is incorrect. > > False, see the HDV vs Mini-DV example. Now imagine HDV at 24.5 mbits > vs Mini-DV at 25 mbits. Do you think HDV will fall apart because of > using 2% more compression? "PTravel" <ptra***@ruyitang.com> writes: The subject line is about a 30gb hard drive camcorder. Nothing stops> > > We're not talking about Micro-MV, which is another toy format. > > MicroMV uses mpeg-2. [at 12 mbits] > So what? Read the the subject line. it from using mpeg-2 at the same bit rate as mpeg-3. What are you getting at? > > > PCM is not lossy, versus MP3, which is. That's apples and There's nothing special about video. Lossy compressor X can give higher> > > oranges. We're comparing mpeg and DV-25, both of which are > > > lossy compression formats. > > > > Irrelevant. For example, 128 kbit MP4 (AAC) sounds better than 160 kbit > > MP3. Both are lossy. > > Okay, try to focus: we were talking about an mpeg2-using hard-drive > camcorder versus miniDV. You want to talk about audio? Go to a different > newsgroup, or at least start a new thread. quality than lossy compressor Y even if X uses a lower bit rate, just like with audio compressors. It just depends on the characteristics of the specific compressor. > One more time: we're not talking about mpeg-encoded HDV, but about the No, we're talking about whether mpeg video is inherently worse than> comparision between the 30 GB hard drive camcorder in the subject line and > miniDV. dv25 video. If a particular implementation happens to do a worse job, that proves nothing about the general case. > > If you want to compare 4 megabit mpeg2 to dv25, that's The subject line says nothing about the bit rate that the 30gb hard> > one thing. But Mpeg is a variable bit rate compressor. > Doesn't matter. Read the subject line. drive camcorder uses. "Paul Rubin" <http://phr.cx@NOSPAM.invalid> wrote in message Nothing stops it -- except the manufacturer's firmware.news:7x7jgseupl.fsf@ruckus.brouhaha.com... > "PTravel" <ptra***@ruyitang.com> writes: > > > > We're not talking about Micro-MV, which is another toy format. > > > MicroMV uses mpeg-2. [at 12 mbits] > > So what? Read the the subject line. > > The subject line is about a 30gb hard drive camcorder. Nothing stops > it from using mpeg-2 at the same bit rate as mpeg-3. What are you getting > at? Show quoteHide quote > One more time: the OP was asking about a specific camcorder, not the> > > > PCM is not lossy, versus MP3, which is. That's apples and > > > > oranges. We're comparing mpeg and DV-25, both of which are > > > > lossy compression formats. > > > > > > Irrelevant. For example, 128 kbit MP4 (AAC) sounds better than 160 kbit > > > MP3. Both are lossy. > > > > Okay, try to focus: we were talking about an mpeg2-using hard-drive > > camcorder versus miniDV. You want to talk about audio? Go to a different > > newsgroup, or at least start a new thread. > > There's nothing special about video. Lossy compressor X can give higher > quality than lossy compressor Y even if X uses a lower bit rate, just > like with audio compressors. It just depends on the characteristics > of the specific compressor. theoretical limits of audio and video compression. > Nope. We're talking about whether the particular implementation of the mpeg> > One more time: we're not talking about mpeg-encoded HDV, but about the > > comparision between the 30 GB hard drive camcorder in the subject line and > > miniDV. > > No, we're talking about whether mpeg video is inherently worse than > dv25 video. codec in a specific camcorder is inherently worse than DV25 video. > If a particular implementation happens to do a worse job, And we're not talking about the general case.> that proves nothing about the general case. > Read the specs on the camera.> > > If you want to compare 4 megabit mpeg2 to dv25, that's > > > one thing. But Mpeg is a variable bit rate compressor. > > Doesn't matter. Read the subject line. > > The subject line says nothing about the bit rate that the 30gb hard > drive camcorder uses. "PTravel" <ptra***@ruyitang.com> writes: Even thought that's how the thread started, threads drift. You>One more time: the OP was asking about a specific camcorder, not the >theoretical limits of audio and video compression. shouldn't make statements that may be true in the restricted context of the original question, but aren't generally true, without qualifying the context. >> No, we're talking about whether mpeg video is inherently worse than The two of you are clearly talking about different things. But there's>> dv25 video. >Nope. We're talking about whether the particular implementation of the mpeg >codec in a specific camcorder is inherently worse than DV25 video. no referee to say which of you is right and which is wrong. If you make statements that apply only to a specific camcorder, say that. Don't say "MPEG is worse than DV", because that statement is wrong on its own. You also said that MPEG at 1/3 the bit rate "throws away 3 times the detail". That's just plain wrong, even in the context of specific consumer camcorders. There's no direct connection between bit rate and perceived detail, particularly when you're comparing MPEG to DV. >> If a particular implementation happens to do a worse job, He is, you aren't. That's life on Usenet.>> that proves nothing about the general case. >And we're not talking about the general case. Dave "Dave Martindale" <da***@cs.ubc.ca> wrote in message I thought the context was sufficiently clear. There is a small cadre ofnews:d8vael$6cn$1@mughi.cs.ubc.ca... > "PTravel" <ptra***@ruyitang.com> writes: > > >One more time: the OP was asking about a specific camcorder, not the > >theoretical limits of audio and video compression. > > Even thought that's how the thread started, threads drift. You > shouldn't make statements that may be true in the restricted context of > the original question, but aren't generally true, without qualifying the > context. mpeg boosters in these newsgroups who think mpeg is the answer to everything -- I suspect that at least some of the drift is attributable to that. My feeling is, the right tool for the right job. I jumped into this thread because I feel that gimmicky cheapo camcorders, like the one in the thread and the raft of DVDcams now out, aren't the right tools for anything. > Exactly.> >> No, we're talking about whether mpeg video is inherently worse than > >> dv25 video. > > >Nope. We're talking about whether the particular implementation of the mpeg > >codec in a specific camcorder is inherently worse than DV25 video. > > The two of you are clearly talking about different things. > But there's I think, after the initial clash of swords, I made the context of my remarks> no referee to say which of you is right and which is wrong. If you make > statements that apply only to a specific camcorder, say that. Don't say > "MPEG is worse than DV", because that statement is wrong on its own. pretty clear. > I agree that there isn't an exact relationship between the bitrate of mpeg> You also said that MPEG at 1/3 the bit rate "throws away 3 times the > detail". That's just plain wrong, even in the context of specific > consumer camcorders. There's no direct connection between bit rate and > perceived detail, particularly when you're comparing MPEG to DV. vs. DV25 and the amount of detail that is discarded. The point, though, is that both discard detail, and mpeg2, at DVD-compliant rates, discards more (for moving video) than DV25. > Guess so.> >> If a particular implementation happens to do a worse job, > >> that proves nothing about the general case. > > >And we're not talking about the general case. > > He is, you aren't. That's life on Usenet. Show quoteHide quote > > Dave "PTravel" <ptra***@ruyitang.com> writes: There is no reason that a camera with a 30gb hard drive (see the subject> I agree that there isn't an exact relationship between the bitrate of mpeg > vs. DV25 and the amount of detail that is discarded. The point, though, is > that both discard detail, and mpeg2, at DVD-compliant rates, discards more > (for moving video) than DV25. line) needs to record at dvd-compliant rates. On 17 Jun 2005 13:43:21 -0700, Paul Rubin
<http://phr.cx@NOSPAM.invalid> wrote: >There is no reason that a camera with a 30gb hard drive (see the subject Tough on you, but the camera discussed in this thread does so :)>line) needs to record at dvd-compliant rates. -martin- -- "Now I want you to say it thrice daily and don't dress a bun" "Paul Rubin" <http://phr.cx@NOSPAM.invalid> wrote in message Except that this one does. Read the specs.news:7xslzgd89i.fsf@ruckus.brouhaha.com... > "PTravel" <ptra***@ruyitang.com> writes: > > I agree that there isn't an exact relationship between the bitrate of mpeg > > vs. DV25 and the amount of detail that is discarded. The point, though, is > > that both discard detail, and mpeg2, at DVD-compliant rates, discards more > > (for moving video) than DV25. > > There is no reason that a camera with a 30gb hard drive (see the subject > line) needs to record at dvd-compliant rates. Paul Rubin <http://phr.cx@NOSPAM.invalid> writes:
>There is no reason that a camera with a 30gb hard drive (see the subject Unless the manufacturer wants to use a hardware encoder that isn't>line) needs to record at dvd-compliant rates. capable of higher rates. Dave "PTravel" <ptra***@ruyitang.com> writes: A noble purpose in itself, but you chose words that could be applied>My feeling is, the right tool for the right job. I jumped into this >thread because I feel that gimmicky cheapo camcorders, like the one in the >thread and the raft of DVDcams now out, aren't the right tools for anything. much too broadly. >I agree that there isn't an exact relationship between the bitrate of mpeg If you'd said *that* in the first place, I suspect there would have been>vs. DV25 and the amount of detail that is discarded. The point, though, is >that both discard detail, and mpeg2, at DVD-compliant rates, discards more >(for moving video) than DV25. much less argument. Another way would have been to say that current consumer video cameras using MPEG-4 produce inferior pictures much of the time when compared to current consumer video cameras recording in DV format on tape. Dave "Dave Martindale" <da***@cs.ubc.ca> wrote in message snipnews:d8vael$6cn$1@mughi.cs.ubc.ca... > "PTravel" <ptra***@ruyitang.com> writes: > >>One more time: the OP was asking about a specific camcorder, not the >>theoretical limits of audio and video compression. > > Even thought that's how the thread started, threads drift. You > shouldn't make statements that may be true in the restricted context of > the original question, but aren't generally true, without qualifying the > context. I agree that threads drift, and one thing leads to another. But I have learned a lot from the discussion and I am really grateful to you all for your detailed responses. It all goes to show that although you might think that the use of DV tape is getting a bit outdated, it is still a very good choice if you are subsequently doing sophisticated video editing, which is one of my main interests. I know this needs a new thread and has been discussed many times, but I guess solid state memory sticks / secure digital memory cards would be better for storage in the future than hard drives. I know that 1GB cards are now common with 4GB promised at the consumer level. But if we were able to choose between a 50GB memory stick and a 50GB hard drive as storage, I guess we would choose the 50GB memory stick? I wonder what the maximum commercial solid state / memory card capacity is at the present? In other words, are hard drives for camcorders likely to survive long into the future? Thanks for your help George On Sat, 18 Jun 2005 09:30:23 +1200, "George S" <George S@enquiry.org> At this moment, the only one with a bit of affordable memory-cardwrote: >I wonder what the maximum commercial >solid state / memory card capacity is at the present? In other words, >are hard drives for camcorders likely to survive long into the future? storage solution, is Panasonic with their P2-cards. But they are quite expensive (new technology). More on: http://www.panasonic.com/business/provideo/p2/index.asp cheers -martin- -- "Now I want you to say it thrice daily and don't dress a bun" "George S" <George S@enquiry.org> writes: You can buy 50GB solid state memory modules but they cost a bloody bundle.> level. But if we were able to choose between a 50GB memory > stick and a 50GB hard drive as storage, I guess we would choose > the 50GB memory stick? I wonder what the maximum commercial > solid state / memory card capacity is at the present? In other words, > are hard drives for camcorders likely to survive long into the future? Hard drives will stay cheaper than solid state for the foreseeable future. Right now, in fact, hard drives are even cheaper than tape. "PTravel" <ptra***@ruyitang.com> writes: Now, that's nonsense. They use different compression methods, so the>Absolutely not. 9 mbps is roughly equivalent to the maximum bit rate for >DVD. DV-25, e.g. miniDV, Digital8 and DV-CAM is 25 mbps, or nearly 3 times >as much. Another way to look at it is, this new toy camera throws away 3 >times as much picture detail as a miniDV camera. rates don't equate to detail, and each method is superior under some conditions. With a mostly static shot, the MPEG intraframe compression can be very efficient, and 9 Mbps gives room to store *more* detail than 25 Mbps DV without the benefit of intraframe compression. On the other hand, in situations where everything in the frame is moving rapidly in various directions, or (worst case) 30 FPS of unrelated still images, intraframe compression gets you nothing, and having 3X higher bit rate means the DV will be substantially better. It all depends on context. >Yes. However, you're capturing 300% more detail with miniDV than with this No, you're capturing 3X as much data. This can mean more or *less*>camera's mpeg2 compression, even at the highest resolution available to the >camera. detail, depending on content. Dave "Dave Martindale" <da***@cs.ubc.ca> wrote in message MiniDV is a video format, i.e. not used for static shots, and that was thenews:d8sk71$gl8$1@mughi.cs.ubc.ca... > "PTravel" <ptra***@ruyitang.com> writes: > > >Absolutely not. 9 mbps is roughly equivalent to the maximum bit rate for > >DVD. DV-25, e.g. miniDV, Digital8 and DV-CAM is 25 mbps, or nearly 3 times > >as much. Another way to look at it is, this new toy camera throws away 3 > >times as much picture detail as a miniDV camera. > > Now, that's nonsense. They use different compression methods, so the > rates don't equate to detail, and each method is superior under some > conditions. basis for the original comparison. Yes, mpeg and DV-25 use different compression formats. And for virtually all video uses, e.g. excluding static slide shows and the like, DV-25 is going to display more detail than mpeg. Show quoteHide quote > With a mostly static shot, the MPEG intraframe compression > can be very efficient, and 9 Mbps gives room to store *more* detail than > 25 Mbps DV without the benefit of intraframe compression. On the other > hand, in situations where everything in the frame is moving rapidly in > various directions, or (worst case) 30 FPS of unrelated still images, > intraframe compression gets you nothing, and having 3X higher bit rate > means the DV will be substantially better. It all depends on context. > > >Yes. However, you're capturing 300% more detail with miniDV than with this > >camera's mpeg2 compression, even at the highest resolution available to the > >camera. > > No, you're capturing 3X as much data. This can mean more or *less* > detail, depending on content. > > Dave "PTravel" <ptra***@ruyitang.com> wrote in news:3hdlg6Fghpv9U1 <SNIP>@individual.net: > Absolutely not. 9 mbps is roughly equivalent to the maximum bit rate <SNIP>> for DVD. DV-25, e.g. miniDV, Digital8 and DV-CAM is 25 mbps, or > nearly 3 times as much. Another way to look at it is, this new toy > camera throws away 3times as much picture detail as a miniDV camera. You need to check your math. Starting at a data rate of 125 Mbps, the 25 Mpbs of DV throws away 100 Mbps, and the 9 Mbps of MPEG-2 for DVD throws away 116 Mbps. To me, this looks like throwing away only 1.16 times as much detail. Actually, since MPEG also expresses some data as a delta from a keyframe, one could argue that even less data is thrown away. HTH, Gino -- Gene E. Bloch (Gino) letters617blochg3251 replace the numbers by "at" and "dotcom" "George S" <George S@enquiry.org> writes: It depends on image content. In all cases, the raw data coming from the>Thanks for the interesting replies. The article says that with a bitrate of >9Mbps, you get 7 hours of recording with the models that have the >30-gig hard drives: JVC GZ-MG50 and GZ-MG30. I wonder what >the bitrate would be for the best quality you can get on consumer level >DV tapes? In other words, could you get quality that is good as DV >tape from a 9Mbps recording on a hard drive? sensor is equivalent to about 250 Mbps (assuming 720x480 pixels, 30 FPS, 24 bit RGB). The colour information is downsampled by a 4:1 factor, immediately cutting the data rate to about 125 Mbps. Then DV compresses each frame individually using JPEG-like compression to 25 Mbps. MPEG has to do about 14:1 compression to get the bit rate down to 9 Mbps, which it accomplishes by comparing frames to the ones before and after in time, and encoding only differences. When the camera is not moving rapidly, and most of the scene isn't either, MPEG compression works beautifully and 9 Mbps MPEG could be higher quality than 25 Mbps DV. On the other hand, rapid movement with little similarity between adjacent frames causes MPEG output to turn to garbage, since there just isn't enough data rate to encode each image separately. I use a video digitizer for a particular purpose: analyzing video from a video game to find problems. I started out with an MPEG-2 digitizer running at 6 Mbps, but it just didn't show me what I needed to see when things were changing fast. I switched to a DV-format digitizer which does work better. (Though I'd *really* like uncompressed video capture if it was available at reasonable cost). >In any event, why You could if you could tolerate the recording time. 30 GB would record>can't you record the miniDV tape format on a hard drive because >you do this in effect when you capture from a DV tape to a hard drive. >A JVC hard drive camcorder doesn't have to use MPEG2 does it? for only 2.5 hours or so instead of 7 hours. So the JVC recorders must use MPEG2 compression. >Another point, even after editing DV tape through a program such Yes, but there are two differences:>as Sony Vegas Video, if you transfer the result to a DVD (which >most people would do rather than back to DV tape) then you >have effectively compressed the video to the MPEG format >anyway! 1. If you shoot in DV, you get real-time compression by 10:1 which is relatively easy to do well. After editing, the MPEG encoding can be done more slowly than real time in software. 2-pass software MPEG encoders do a better job than a 1-pass MPEG hardware encoder that has to operate in real time. 2. Editing DV is easy; each frame is independent so the editor can assemble them in any sequence at any time. Only transitions and special effects need rendering. Editing MPEG is harder since most frames depend on frames before and after them. Unless you restrict yourself to cutting at I-frame locations only, an MPEG editor has to be prepared to decode a number of frames on either side of the edit point, then re-encode them without exceeding the maximum data rate. And at this point you've MPEG compressed those frames twice, not once. Dave On 15 Jun 2005 20:16:57 -0700, Paul Rubin
<http://phr.cx@NOSPAM.invalid> wrote: >Today's prosumer HDTV camcorders use Yeah, but did you ever try do to some fast panning? Here the mini-DV>mpeg-like compression schemes to record 1080-line HDTV at the same bit >rate as mini-DV. compression certainly beats the pants of HDV. -martin- -- "Now I want you to say it thrice daily and don't dress a bun" "Martin Heffels" <mana***@usg-managers.com> wrote in message Martin, you just can't help yourself can you?news:gqb2b15amqff7n9p2tg2lash4hsjo49g0q@4ax.com... > On 15 Jun 2005 20:16:57 -0700, Paul Rubin > <http://phr.cx@NOSPAM.invalid> wrote: > > >Today's prosumer HDTV camcorders use > >mpeg-like compression schemes to record 1080-line HDTV at the same bit > >rate as mini-DV. > > Yeah, but did you ever try do to some fast panning? Here the mini-DV > compression certainly beats the pants of HDV. > > -martin- A half competent DOP understands the limitations of any given format and works within them. I have seen unmotivated pans on HDV that indeed do soften until the camera comes to rest e.g. a panoramic pan. The simple solution is to motivate the pan i.e draw the audience's attention to a subject in the frame while panning e.g following a travelling car or a running person. The subject will not exhibit softening as it doesn't move or change shape much within the frame and the audience's gaze will be drawn away from the softened background. HDV in 10 o.o.f. 10 situations looks better than miniDV if you are competent camera operator. Its truely amazing that the format detractors seem to pick out fast panning as THE point HDV falls over. This either shows a fundamental lack in their directing ability or a complete lack of understanding of how the audience views a series of moving images. On Thu, 16 Jun 2005 11:59:04 +0100, "Specs" <No.Spam@Thanks.com> You are right in that following a subject, will distract from blockywrote: >Its truely amazing that the format detractors seem to pick out fast panning >as THE point HDV falls over. This either shows a fundamental lack in their >directing ability or a complete lack of understanding of how the audience >views a series of moving images. artifacts, but that is not always what you want if you do a pan. I will brace myself if HDV is going to be used to shoot an action movie with a lot of fast pans and tilts. With DVD MPEG2 compression, you can test for yourself what a high compression will lead to. It's no guessing, it's just plain simple truth. -martin- -- "Now I want you to say it thrice daily and don't dress a bun"
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"Martin Heffels" <mana***@usg-managers.com> wrote in message Blocky artifacts? Have you actually seen these or are you still makingnews:hdn2b1d22mchecu866ep9bsfm7il7h5h4e@4ax.com... > On Thu, 16 Jun 2005 11:59:04 +0100, "Specs" <No.Spam@Thanks.com> > wrote: > > >Its truely amazing that the format detractors seem to pick out fast panning > >as THE point HDV falls over. This either shows a fundamental lack in their > >directing ability or a complete lack of understanding of how the audience > >views a series of moving images. > > You are right in that following a subject, will distract from blocky > artifacts, but that is not always what you want if you do a pan. > I will brace myself if HDV is going to be used to shoot an action > movie with a lot of fast pans and tilts. With DVD MPEG2 compression, > you can test for yourself what a high compression will lead to. > It's no guessing, it's just plain simple truth. > > -martin- > pronouncements on the basis of what you think happens. I think the latter, eh Martin? In my experience the HDV compression increases the overall motion blur of moving objects and is far from unsightly. HDV does not limit the filmmaker to any particular genre and to suggest such is daft. My advice to anyone reading this thread who might have been put off the format by people like Martin is to embrace the new format, experiment with the new aesthetics and take the jobs of the naysayers! On Thu, 16 Jun 2005 14:25:52 +0100, "Specs" <No.Spam@Thanks.com> I have seen them, played back off tape.wrote: >Blocky artifacts? Have you actually seen these or are you still making >pronouncements on the basis of what you think happens. I think the latter, >eh Martin? >In my experience the HDV compression increases the overall motion blur of Feel free to use it for any programme form you like. I don't say you>moving objects and is far from unsightly. HDV does not limit the filmmaker >to any particular genre and to suggest such is daft. can't use it for particular forms, but I am aware that in some forms, the picture quality will suffer. >My advice to anyone reading this thread who might have been put off the You don't seem to have remembered anything from what I wrote in the>format by people like Martin is to embrace the new format, experiment with >the new aesthetics and take the jobs of the naysayers! previous thread, when you came up with a lot of unfundamental attacks on me. Again: you don't know who I am, you don't know how I work, but you still seem to have an opinion about this. Weird..... -martin- -- "Now I want you to say it thrice daily and don't dress a bun"
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"Martin Heffels" <mana***@usg-managers.com> wrote in message Yo Specs.. ease up on Martin a little! ;p. You'll find he's a prettynews:q903b1ts4hg1rtmtud43fm07q5n5lv5jfb@4ax.com... > On Thu, 16 Jun 2005 14:25:52 +0100, "Specs" <No.Spam@Thanks.com> > wrote: > > >Blocky artifacts? Have you actually seen these or are you still making > >pronouncements on the basis of what you think happens. I think the latter, > >eh Martin? > > I have seen them, played back off tape. > > >In my experience the HDV compression increases the overall motion blur of > >moving objects and is far from unsightly. HDV does not limit the filmmaker > >to any particular genre and to suggest such is daft. > > Feel free to use it for any programme form you like. I don't say you > can't use it for particular forms, but I am aware that in some forms, > the picture quality will suffer. > > >My advice to anyone reading this thread who might have been put off the > >format by people like Martin is to embrace the new format, experiment with > >the new aesthetics and take the jobs of the naysayers! > > You don't seem to have remembered anything from what I wrote in the > previous thread, when you came up with a lot of unfundamental attacks > on me. Again: you don't know who I am, you don't know how I work, but > you still seem to have an opinion about this. Weird..... > > -martin- > > -- > "Now I want you to say it thrice daily and don't dress a bun" congenial fellow. That said, I am shooting a music video in July and there will be a LOT of compositing done on it. Keying and roto and the like.. I decided to go with HD instead ofr HDV because of the MPEG artifacts that would affect the compositing process. There is no getting around MPEG. > LOL! Pot calling the kettle black! I remember Nappy vs Reuther!> Yo Specs.. ease up on Martin a little! ;p. You'll find he's a pretty > congenial fellow. > Obviously if you have the budget for HD then of course use the better> That said, I am shooting a music video in July and there will be a LOT of > compositing done on it. Keying and roto and the like.. I decided to go with > HD instead ofr HDV because of the MPEG artifacts that would affect the > compositing process. There is no getting around MPEG. > format. But hang on a minute for compositing work ALL HD formats, with the exception of HDCAM SR, have issues with Keying. DV100 even with its 4:2:2 is still only 8bit and pretty much only slightly above SD resolution so on large screens a stairstepped edge is still seen. HDCAM 3:1:1 is a pain to key too! But lets not compare apples to gold plated ones. "Specs" <No.Spam@Thanks.com> wrote in message Yeah.. I wonder how he is? I was going to send an email to see. Remember henews:42b1a5b4$0$2414$ed2619ec@ptn-nntp-reader02.plus.net... > > > > > > Yo Specs.. ease up on Martin a little! ;p. You'll find he's a pretty > > congenial fellow. > > LOL! Pot calling the kettle black! I remember Nappy vs Reuther! dropped out because of health reasons and I haven't heard a word. I do hope he is healthy and OK. It WAS all his fault though. ;P Show quoteHide quote > Compared to ANY other video format HD at 1920x1080 should be a breeze. Si?> > > > That said, I am shooting a music video in July and there will be a LOT of > > compositing done on it. Keying and roto and the like.. I decided to go > with > > HD instead ofr HDV because of the MPEG artifacts that would affect the > > compositing process. There is no getting around MPEG. > > > > Obviously if you have the budget for HD then of course use the better > format. But hang on a minute for compositing work ALL HD formats, with the > exception of HDCAM SR, have issues with Keying. DV100 even with its 4:2:2 is > still only 8bit and pretty much only slightly above SD resolution so on > large screens a stairstepped edge is still seen. HDCAM 3:1:1 is a pain to > key too! But lets not compare apples to gold plated ones. No? Show quoteHide quote > >
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"nap" <noem***@all.com> wrote in message 4:2:2news:fslse.2817$NU5.1805@newssvr13.news.prodigy.com... > > "Specs" <No.Spam@Thanks.com> wrote in message > news:42b1a5b4$0$2414$ed2619ec@ptn-nntp-reader02.plus.net... > > > > > > > > > > Yo Specs.. ease up on Martin a little! ;p. You'll find he's a pretty > > > congenial fellow. > > > > LOL! Pot calling the kettle black! I remember Nappy vs Reuther! > > Yeah.. I wonder how he is? I was going to send an email to see. Remember he > dropped out because of health reasons and I haven't heard a word. I do hope > he is healthy and OK. It WAS all his fault though. ;P > > > > > > > > > > That said, I am shooting a music video in July and there will be a LOT > of > > > compositing done on it. Keying and roto and the like.. I decided to go > > with > > > HD instead ofr HDV because of the MPEG artifacts that would affect the > > > compositing process. There is no getting around MPEG. > > > > > > > Obviously if you have the budget for HD then of course use the better > > format. But hang on a minute for compositing work ALL HD formats, with > the > > exception of HDCAM SR, have issues with Keying. DV100 even with its > is What format are you shooting? HDCAM and DV100 are not full raster to my> > still only 8bit and pretty much only slightly above SD resolution so on > > large screens a stairstepped edge is still seen. HDCAM 3:1:1 is a pain to > > key too! But lets not compare apples to gold plated ones. > > > Compared to ANY other video format HD at 1920x1080 should be a breeze. Si? > No? > knowledge. Are you shooting uncompressed? Viper?
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"Specs" <No.Spam@Thanks.com> wrote in message We'll be using the FW900. I am not the DP. Producing / finishing this one.news:42b1e9d0$0$2395$ed2619ec@ptn-nntp-reader02.plus.net... > > "nap" <noem***@all.com> wrote in message > news:fslse.2817$NU5.1805@newssvr13.news.prodigy.com... > > > > "Specs" <No.Spam@Thanks.com> wrote in message > > news:42b1a5b4$0$2414$ed2619ec@ptn-nntp-reader02.plus.net... > > > > > > > > > > > > > > Yo Specs.. ease up on Martin a little! ;p. You'll find he's a pretty > > > > congenial fellow. > > > > > > LOL! Pot calling the kettle black! I remember Nappy vs Reuther! > > > > Yeah.. I wonder how he is? I was going to send an email to see. Remember > he > > dropped out because of health reasons and I haven't heard a word. I do > hope > > he is healthy and OK. It WAS all his fault though. ;P > > > > > > > > > > > > > > > That said, I am shooting a music video in July and there will be a LOT > > of > > > > compositing done on it. Keying and roto and the like.. I decided to go > > > with > > > > HD instead ofr HDV because of the MPEG artifacts that would affect the > > > > compositing process. There is no getting around MPEG. > > > > > > > > > > Obviously if you have the budget for HD then of course use the better > > > format. But hang on a minute for compositing work ALL HD formats, with > > the > > > exception of HDCAM SR, have issues with Keying. DV100 even with its > 4:2:2 > > is > > > still only 8bit and pretty much only slightly above SD resolution so on > > > large screens a stairstepped edge is still seen. HDCAM 3:1:1 is a pain > to > > > key too! But lets not compare apples to gold plated ones. > > > > > > Compared to ANY other video format HD at 1920x1080 should be a breeze. > Si? > > No? > > > What format are you shooting? HDCAM and DV100 are not full raster to my > knowledge. Are you shooting uncompressed? Viper? > Show quoteHide quote > > > > > Yo Specs.. ease up on Martin a little! ;p. You'll find he's a pretty I hope he got over whatever he had. Sounded nasty.> > > congenial fellow. > > > > LOL! Pot calling the kettle black! I remember Nappy vs Reuther! > > Yeah.. I wonder how he is? I was going to send an email to see. Remember he > dropped out because of health reasons and I haven't heard a word. I do hope > he is healthy and OK. It WAS all his fault though. ;P > Anyone heard how he is? He's just been taking his time to put together another website of Sony HDV vs Canon XL2 reviews together I suspect! Martin Heffels wrote:
> Yeah, but did you ever try do to some fast panning? Here the mini-DV Martin, did you not read John Lubran's (aka Moving Vision) response to> compression certainly beats the pants of HDV. this issue in the "1st Prosumer Camera?" thread? "I've been reading lots of stuff here about the Z1 and HDV and as a person currently working with it I'd have to say that most of it is utter tosh. The methodology and equipment required to produce HD programmes from HDV is not rocket science but it is very specific, the results clearly leave all SD formats, including Digi Beta, so far behind they're nearly out of sight. Furthermore we've even tested digitising HDV into the relatively inferior Premier Pro HDV plug in, editing it with rendered effects and exporting back to HDV just to see the much stated deterioration and compression artefacts so loudly announced by the hypothetical incognisanti here. Needless to say the edited copy was as clean as the original rushes. In the test we filmed fast moving traffic from different angles and distances. The incognisanti here will tell you that HDV simply can't handle motion and that further more the format suffers from frequent half second glitches. Well let me tell you right now that after shooting some 40 hours of HDV in the FX1 and Z1 none of these onerous conditions have yet to be experienced. Even furthermore, all this HDV was recorded on to the same bog standard consumer Panasonic miniDV tape that we've been using since 1995. Wishfully asserting that SD 4x3 formats are going to have much more life at a professional level just because one is so invested in it and don't want the truth to be true, is redolent of King Canute ordering the tide not to come in. And as for questioning the Z1's comparative quality in DV or DVCAM mode I can tell you that it blows the current compacts including XL2's, PD170's and DVX100A's clean away. The new and unique 1/3rd inch 16:9 Super HAD CCD's produce SD images with significantly greater contrast and colour latitude than I've seen on any compact yet. The Z1 in DVCAM mode is much closer to the DSR500/570, so close in fact that it's a feat of nerd glory to be able to tell their footage apart." Sounds to me like it's not an issue :-) Mike On 16 Jun 2005 06:18:49 -0700, "Mike Kujbida" <kuj***@sympatico.ca> I have read it, but I know there are limitations. Maybe you are not aswrote: >Sounds to me like it's not an issue :-) critical as me, but I see artifacts which I don't like. And one of them is caused by the codec going haywire on fast moving images. I liked the overall image as well, by the way. I know you can workaround those limitations. Every format has it's limitations. It's a magnicficent camera and will definetly change the world of low-budget filmmaking/tv/doco/camjo's. I am looking forward to using a Z1U in a few months, but I am aware of it's limitations, and we'll work around them during the shooting/posting. cheers -martin- -- "Now I want you to say it thrice daily and don't dress a bun" "Paul Rubin" <http://phr.cx@NOSPAM.invalid> wrote in message Hunh? Of course it does. Both DV-25 and mpeg are lossy compressionnews:7x7jgv0z4m.fsf@ruckus.brouhaha.com... > "George S" <George S@enquiry.org> writes: > > I wondered if these new hard-drive-based camcorders would produce > > video with as good a quality as you can get from DV tapes? > > There's nothing special about the DV format. Just because it uses a > lower compression ratio than mpeg-2 doesn't mean the quality is > better. formats. However, DV-25 results in about 5-to-1 compression, whereas mpeg is another order of magnitude greater. >It just means it's an older standard from an era when less Absolute nonsense. If you can't see the difference between mpeg2- and DV-25> processing power was available. encoded material, then you either need a new television or you should get your glasses checked. > Today's prosumer HDTV camcorders use You're comparing apples to oranges. Given the same material, whether SD or> mpeg-like compression schemes to record 1080-line HDTV at the same bit > rate as mini-DV. I think most people will say that the HDTV video, > displayed on a high res monitor, beats the pants of regular mini-DV in > image quality. HD, it will look better (and, in the case of SD, far better) when compressed as DV-25 than as mpeg. > > There's nothing special about the DV format. Just because it uses a Entirely wrong. An SD stream encoded at 25Mbps MPEG2 should look a whole> > lower compression ratio than mpeg-2 doesn't mean the quality is > > better. > > Hunh? Of course it does. Both DV-25 and mpeg are lossy compression > formats. However, DV-25 results in about 5-to-1 compression, whereas mpeg > is another order of magnitude greater. lot better than DV25. Anyone remember Betacam SX by any chance?
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"Specs" <No.Spam@Thanks.com> wrote in message That's exactly what I said. Try reading more carefully next time.news:42b1a11a$0$2394$ed2619ec@ptn-nntp-reader02.plus.net... > > > > > There's nothing special about the DV format. Just because it uses a > > > lower compression ratio than mpeg-2 doesn't mean the quality is > > > better. > > > > Hunh? Of course it does. Both DV-25 and mpeg are lossy compression > > formats. However, DV-25 results in about 5-to-1 compression, whereas mpeg > > is another order of magnitude greater. > > Entirely wrong. An SD stream encoded at 25Mbps MPEG2 should look a whole > lot better than DV25. Anyone remember Betacam SX by any chance? Show quoteHide quote > >
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"PTravel" <ptra***@ruyitang.com> wrote in message That's not what you said at all.news:3hdmuoFgjlb1U1@individual.net... > > "Specs" <No.Spam@Thanks.com> wrote in message > news:42b1a11a$0$2394$ed2619ec@ptn-nntp-reader02.plus.net... > > > > > > > > There's nothing special about the DV format. Just because it uses a > > > > lower compression ratio than mpeg-2 doesn't mean the quality is > > > > better. > > > > > > Hunh? Of course it does. Both DV-25 and mpeg are lossy compression > > > formats. However, DV-25 results in about 5-to-1 compression, whereas > mpeg > > > is another order of magnitude greater. > > > > Entirely wrong. An SD stream encoded at 25Mbps MPEG2 should look a whole > > lot better than DV25. Anyone remember Betacam SX by any chance? > > That's exactly what I said. Try reading more carefully next time. > You said, "Both DV-25 and mpeg are lossy compression formats. However, DV-25 results in about 5-to-1 compression, whereas mpeg is another order of magnitude greater." Which is incorrect for a given bit rate. "PTravel" <ptra***@ruyitang.com> wrote in news:3hdks7Fgj31pU1 <SNIP>@individual.net: > Hunh? Of course it does. Both DV-25 and mpeg are lossy compression <SNIP>> formats. However, DV-25 results in about 5-to-1 compression, whereas > mpeg is another order of magnitude greater. You need to check your math. An order of magnitude is a factor of ten, and 9 Mbps is 1/2.77 of 25 Mbps, not 1/10 of 25 Mbps. As a physicist, mathematician, and programmer, I have always used the definition of order of magnitude as a factor of ten. However, to be safe, I also took the precaution of looking in my American Heritage Dictionary, in case the 'civilian' definition differed. It did not. HTH, Gino -- Gene E. Bloch (Gino) letters617blochg3251 replace the numbers by "at" and "dotcom"
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"Gene E. Bloch" <hamburger@NOT_SPAM.invalid> wrote in message You're right, I over-stated the case.news:Xns9677B6FAAEBCAstrolabe@216.196.97.136... > "PTravel" <ptra***@ruyitang.com> wrote in news:3hdks7Fgj31pU1 > @individual.net: > > <SNIP> > > > Hunh? Of course it does. Both DV-25 and mpeg are lossy compression > > formats. However, DV-25 results in about 5-to-1 compression, whereas > > mpeg is another order of magnitude greater. > > <SNIP> > > You need to check your math. An order of magnitude is a factor of ten, > and 9 Mbps is 1/2.77 of 25 Mbps, not 1/10 of 25 Mbps. > > As a physicist, mathematician, and programmer, I have always used the > definition of order of magnitude as a factor of ten. However, to be > safe, I also took the precaution of looking in my American Heritage > Dictionary, in case the 'civilian' definition differed. It did not. Show quoteHide quote > > HTH, > Gino > > -- > Gene E. Bloch (Gino) > letters617blochg3251 > replace the numbers by "at" and "dotcom"
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"PTravel" <ptra***@ruyitang.com> wrote in What fun! Two people talking about the same thing on this thread ;-)news:3hg8pnFgiidhU1@individual.net: > > "Gene E. Bloch" <hamburger@NOT_SPAM.invalid> wrote in message > news:Xns9677B6FAAEBCAstrolabe@216.196.97.136... >> "PTravel" <ptra***@ruyitang.com> wrote in news:3hdks7Fgj31pU1 >> @individual.net: >> >> <SNIP> >> >> > Hunh? Of course it does. Both DV-25 and mpeg are lossy >> > compression formats. However, DV-25 results in about 5-to-1 >> > compression, whereas mpeg is another order of magnitude >> > greater. >> >> <SNIP> >> >> You need to check your math. An order of magnitude is a factor of >> ten, and 9 Mbps is 1/2.77 of 25 Mbps, not 1/10 of 25 Mbps. >> >> As a physicist, mathematician, and programmer, I have always used >> the definition of order of magnitude as a factor of ten. However, >> to be safe, I also took the precaution of looking in my American >> Heritage Dictionary, in case the 'civilian' definition differed. >> It did not. > > You're right, I over-stated the case. > It has been kind of fun, even though there are only 63 posts present as I write this, so it's not a huge thread... Gino -- Gene E. Bloch (Gino) letters617blochg3251 replace the numbers by "at" and "dotcom" People here have various ideas about the need to maintain quality in
their video conversions. It would be interesting to know what kind of equipment the purists are using to shoot their original video. My best cameras are Sony PD150's - something George Lucas would not even use as paperweights - so I don't lose too much sleep about the quality loss inherent in an extra format conversion. That argument aside, the first question about these direct-to-mpg cameras should be whether or not their compression algorithms are appropriate to the overall quality of the camera, and good enough to satisfy you. The mpg standard allows a big range of quality, and what a moderately-priced camcorder is designed to do in real-time won't likely compare with what you can do with your desktop computer, especially if you don't expect realtime conversion. If you're happy enough with the quality, and convince yourself that an extra conversion to AVI stays within your personal quality standards, the issue of editability of the material is pretty moot. Directly editing mpg is tedious because the program can't instantly show you the frame you stopped scrolling at, but that problem is easily enough dispatched by converting to AVI and editing that. Don't forget that it's not particularly hard to record DV AVI to hard drive using any miniDV (or other) camera that passes its signal out onto its firewire port in real time. Firestore and others offer tiny boxes that clip into your camera's shoe and record 40GB (3+ hours) or so of exactly what's going on to the tape (or not, if you choose to depend on the hard drive.) Show quoteHide quote "George S" <George S@enquiry.org> wrote: ----------------->I see that JVC has introduced a 30GB hard drive camcorder, the Everio: > >http://www.camcorderinfo.com/content/JVC-Introduces-Four-Hard-Drive-Based-Everio-Camcorders.htm > >The above write-up by Robin Liss says that, according to JVC, >the 30GB Everio models can hold as much video as 22 DVD discs >and the quality is just as good. JVC even placed their model next to >a Sony DCR-DVD201 in a side by side video quality comparison. >The new hard drive Everios record video in MPEG2 format, which >is the standard used in DVD camcorders. > >I wondered if these new hard-drive-based camcorders would produce >video with as good a quality as you can get from DV tapes? I guess 30GB >is a lot of storage, equivalent to more than two 1-hour DV tapes, but >if you do fill up your hard disk while you are walking in the hills, I >suppose you would need a portable computer with you to download >the video onto so that you could clear the hard drive? The advantage >of tapes and DVDs is that you can have plenty of these with you >if you are going to be a long time away from your computer in >remote places! Does anyone know whether there would be any >major problems in editing video from a camcorder with a hard drive? >For example, would you be able to satisfactorily use a video >editing program such as Vegas Video? Thanks for your comments. > www.Newsgroup-Binaries.com - *Completion*Retention*Speed* Access your favorite newsgroups from home or on the road -----------------
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"JT" <NgPos***@missing.org> wrote in message I guess I don't understand this. I use a VX2000, the consumer version ofnews:bb32b11omo193bqo5lr3mguvroren05of3@4ax.com... > People here have various ideas about the need to maintain quality in > their video conversions. It would be interesting to know what kind of > equipment the purists are using to shoot their original video. My best > cameras are Sony PD150's - something George Lucas would not even use > as paperweights - so I don't lose too much sleep about the quality > loss inherent in an extra format conversion. > > That argument aside, the first question about these direct-to-mpg > cameras should be whether or not their compression algorithms are > appropriate to the overall quality of the camera, and good enough to > satisfy you. The mpg standard allows a big range of quality, and what > a moderately-priced camcorder is designed to do in real-time won't > likely compare with what you can do with your desktop computer, > especially if you don't expect realtime conversion. your PD150. Are you saying you can't see the difference between mpeg-encoded video and DV-25 straight out of the camera? I certainly can, and that's just a single transcode from the edited DV-codec-encoded AVI to mpeg for burning to DVD. I recently put together a project in which I had to use clips from some DVDs I had burned previously (the source material doesn't exist anymore). This entailed importing the re-named VOB into Premiere Pro (using the Mainconcept HD Mpeg plug-in), editing (which was an enormous pain), exporting the complete project to AVI and then retranscoding to mpeg to burn the final project. The difference in quality between those clips sourced in DV-25 and the mpegs from the DVDs was, to say the least, dramatic and clearly visible. Out of curiosity, and with all respect, if twice-transcoded mpeg quality is acceptable to you, why do you need a PD-150? What do you use it for? Show quoteHide quote > verio-Camcorders.htm> If you're happy enough with the quality, and convince yourself that an > extra conversion to AVI stays within your personal quality standards, > the issue of editability of the material is pretty moot. Directly > editing mpg is tedious because the program can't instantly show you > the frame you stopped scrolling at, but that problem is easily enough > dispatched by converting to AVI and editing that. > > Don't forget that it's not particularly hard to record DV AVI to hard > drive using any miniDV (or other) camera that passes its signal out > onto its firewire port in real time. Firestore and others offer tiny > boxes that clip into your camera's shoe and record 40GB (3+ hours) or > so of exactly what's going on to the tape (or not, if you choose to > depend on the hard drive.) > > > > > > > > > "George S" <George S@enquiry.org> wrote: > > >I see that JVC has introduced a 30GB hard drive camcorder, the Everio: > > > >http://www.camcorderinfo.com/content/JVC-Introduces-Four-Hard-Drive-Based-E Show quoteHide quote > > > >The above write-up by Robin Liss says that, according to JVC, > >the 30GB Everio models can hold as much video as 22 DVD discs > >and the quality is just as good. JVC even placed their model next to > >a Sony DCR-DVD201 in a side by side video quality comparison. > >The new hard drive Everios record video in MPEG2 format, which > >is the standard used in DVD camcorders. > > > >I wondered if these new hard-drive-based camcorders would produce > >video with as good a quality as you can get from DV tapes? I guess 30GB > >is a lot of storage, equivalent to more than two 1-hour DV tapes, but > >if you do fill up your hard disk while you are walking in the hills, I > >suppose you would need a portable computer with you to download > >the video onto so that you could clear the hard drive? The advantage > >of tapes and DVDs is that you can have plenty of these with you > >if you are going to be a long time away from your computer in > >remote places! Does anyone know whether there would be any > >major problems in editing video from a camcorder with a hard drive? > >For example, would you be able to satisfactorily use a video > >editing program such as Vegas Video? Thanks for your comments. > > > > ----------------- > www.Newsgroup-Binaries.com - *Completion*Retention*Speed* > Access your favorite newsgroups from home or on the road > ----------------- George S wrote:
> I see that JVC has introduced a 30GB hard drive camcorder, the Everio: .... says that it has a USB2.0 port to connect to the computer ...Suppose> > http://www.camcorderinfo.com/content/JVC-Introduces-Four-Hard-Drive-Based-Everio-Camcorders.htm > you connect it to a Windows XP system, what are the file extensions that will be seen in the mounted camcorder? DV25? MMX? On Fri, 17 Jun 2005 13:51:06 -0400, Rick Merrill <jayn***@comcast.net>
wrote: >DV25? MMX? How about MPEG2 :)-martin- -- "Now I want you to say it thrice daily and don't dress a bun" 
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