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Software quality issues?

Author
26 Jun 2006 8:11 PM
lyndon
Having imported video into computer and creating an
iMovie/QT file of it the quality wasn't too bad. But
when it went thru iDVD to a DVD, the quality really
dropped off. (Resolution was not great) Is this a
software problem or ......? Would FinalCutPro put
out a higher quality picture?

(Original video was dig8 from Sony TRV 460 via Firewire
to Mac G4 (Panther) and iMovie 4 to iDVD 5 on (Tiger)!)

Thanks
Lyndon

Author
26 Jun 2006 8:44 PM
PTravel
"lyndon" <lynd***@easyjunktrapstreet.com> wrote in message
news:lyndonr-332C9F.13115126062006@sn-ip.vsrv-sjc.supernews.net...
> Having imported video into computer and creating an
> iMovie/QT file of it the quality wasn't too bad. But
> when it went thru iDVD to a DVD, the quality really
> dropped off. (Resolution was not great) Is this a
> software problem or ......? Would FinalCutPro put
> out a higher quality picture?

I'm not a Mac user, but . . .

Producing a DVD requires transcoding DV-codec-encoded AVI to MPEG2, a lossy,
temporally-compressed format.  The transcoding process is critical to final
video quality -- such things as bit precision, motion search, compression
rate, matrix structure, number of analysis passes, variable versus constant
bit rate compression, and other factors determine how good the final video
will look.  Most entry-level consumer products, like iDVD, compromise on
transcode quality in the interest of speed of output.  Final Cut Pro is,
primarily, an editing program -- I don't whether it is intended for
authoring DVDs from the timeline, or can simply produce a quick-and-dirty
DVD for evaluation purposes (lots of comparable prosumer editing packages go
the quick-and-dirty DVD route).  You may wish to investigate stand-alone
authoring and/or transcoding packages.   However, it is clear that poor
video on the DVD when compared to the edited AVI is the result of
transcoding that has been optimized for speed rather than quality.

For what it's worth, as a PC user, I edit in Adobe Premiere Pro, which is a
prosumer editing program comparable to Final Cut Pro.  I always use a
standalone transcoder (tmpgenc) that allows me to optimize for quality and
then import the resulting mpeg2 file into a separate authoring program
(Adobe Encore).  This allows me to produce DVDs that approach commercial
DVDs in terms of video quality.

Show quoteHide quote
>
> (Original video was dig8 from Sony TRV 460 via Firewire
> to Mac G4 (Panther) and iMovie 4 to iDVD 5 on (Tiger)!)
>
> Thanks
> Lyndon
Author
4 Jul 2006 10:26 PM
lyndon
In article <4gav96F1ltlv***@individual.net>,
Show quoteHide quote
"PTravel" <ptra***@ruyitang.com> wrote:

> "lyndon" <lynd***@easyjunktrapstreet.com> wrote in message
> news:lyndonr-332C9F.13115126062006@sn-ip.vsrv-sjc.supernews.net...
> > Having imported video into computer and creating an
> > iMovie/QT file of it the quality wasn't too bad. But
> > when it went thru iDVD to a DVD, the quality really
> > dropped off. (Resolution was not great) Is this a
> > software problem or ......? Would FinalCutPro put
> > out a higher quality picture?

> Producing a DVD requires transcoding DV-codec-encoded AVI to MPEG2, a lossy,
> temporally-compressed format.  The transcoding process is critical to final
> video quality -- such things as bit precision, motion search, compression
> rate, matrix structure, number of analysis passes, variable versus constant
> bit rate compression, and other factors determine how good the final video
> will look.  Most entry-level consumer products, like iDVD, compromise on
> transcode quality in the interest of speed of output.  Final Cut Pro is,
> primarily, an editing program -- I don't whether it is intended for
> authoring DVDs from the timeline, or can simply produce a quick-and-dirty
> DVD for evaluation purposes (lots of comparable prosumer editing packages go
> the quick-and-dirty DVD route).  You may wish to investigate stand-alone
> authoring and/or transcoding packages.   However, it is clear that poor
> video on the DVD when compared to the edited AVI is the result of
> transcoding that has been optimized for speed rather than quality.

Thanks for the response, but I found what seems to be the source
of the problem. I had produced an mp4 with iMovie and sent that
to iDVD which did have a real dropoff in picture quality. But
going back to the original iMovie file and exporting directly to
to iDVD resulted in a very markedly improved picture. In fact, it
came out better than I thought it would before I even started the
whole DVD creating process.

Lyndon
Author
4 Jul 2006 11:56 PM
ptravel
lyndon wrote:
Show quoteHide quote
> In article <4gav96F1ltlv***@individual.net>,
>  "PTravel" <ptra***@ruyitang.com> wrote:
>
> > "lyndon" <lynd***@easyjunktrapstreet.com> wrote in message
> > news:lyndonr-332C9F.13115126062006@sn-ip.vsrv-sjc.supernews.net...
> > > Having imported video into computer and creating an
> > > iMovie/QT file of it the quality wasn't too bad. But
> > > when it went thru iDVD to a DVD, the quality really
> > > dropped off. (Resolution was not great) Is this a
> > > software problem or ......? Would FinalCutPro put
> > > out a higher quality picture?
>
> > Producing a DVD requires transcoding DV-codec-encoded AVI to MPEG2, a lossy,
> > temporally-compressed format.  The transcoding process is critical to final
> > video quality -- such things as bit precision, motion search, compression
> > rate, matrix structure, number of analysis passes, variable versus constant
> > bit rate compression, and other factors determine how good the final video
> > will look.  Most entry-level consumer products, like iDVD, compromise on
> > transcode quality in the interest of speed of output.  Final Cut Pro is,
> > primarily, an editing program -- I don't whether it is intended for
> > authoring DVDs from the timeline, or can simply produce a quick-and-dirty
> > DVD for evaluation purposes (lots of comparable prosumer editing packages go
> > the quick-and-dirty DVD route).  You may wish to investigate stand-alone
> > authoring and/or transcoding packages.   However, it is clear that poor
> > video on the DVD when compared to the edited AVI is the result of
> > transcoding that has been optimized for speed rather than quality.
>
> Thanks for the response, but I found what seems to be the source
> of the problem. I had produced an mp4 with iMovie and sent that
> to iDVD which did have a real dropoff in picture quality. But
> going back to the original iMovie file and exporting directly to
> to iDVD resulted in a very markedly improved picture. In fact, it
> came out better than I thought it would before I even started the
> whole DVD creating process.

Well, sure.  When you output to mp4 you are transcoding to a lossy
compressed format, i.e. you lose quality.  When you input that to iDVD
and burn a DVD, you are re-transcoding to mpeg2, another lossy
compressed format, i.e. you lose quality.  By introducing the extra,
and unnecessary, transcode to mp4 you lose a significant amount of
video quality.


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>
> Lyndon