Confused over two methods of DVD burning and conversion...

[sstrungis]

Hi forum-ers,

I have read, and searched, and am a little clueless.

I have 20-odd episodes of a vintage cartoon show in AVI (Divx) format that I have started to burn to 4.7gb discs as TV-watchable. These are a little on the low-res side, so the enlargement to DVD format has resulted in some pixelation. Turns out that I can fit 4 20 minute episodes on one single layer disc using Toast 6. That makes sense looking at the minutes. 83 minutes--give or take a few seconds--is about the limit of a single layer disc.

My conundrum is...After reading around on here I decided to bail on Toast for one disc and I used ffmpeg to convert the avi's to MPEG-TS 720x576. I also used Sizzle to make up a nice menu with pictures and such that kicks Toast's menu's butt. Now when I created an image of 4 episodes, I got a disc image that was only 2.2 gigs. It stands to reason that it would be closer to the 4.7 gb limit of the DVD's capacity like Toast does.

When I shot the image to the iPod and down to the missus's iMac with the Superdrive Toast reports it as a DVD-ROM (UDF). It also shows that the disc is half full at the gauge.

So, what am I doing?...Right or wrong? Is the UDF format a watchable disc? Why are four episodes now less than half a disc? I would love to continue with Sizzle, but I don't want to make a coaster.

Any advice would be great as I am sort of lost in all the posts, and none seem to match my troubles.

Thanks,
Scott Strungis

[terryj]

ok, lets take it from the top:

Your first disc was created in Toast,
20 min 4 episodes onto Toast.
I'm guessing this was set for High Quality setting, which
translates to Toast Constant 1 pass VBR with a High bitrate.

Since DIVX isn't a QT compatible spec, Toast would have to try and re-encode the DIVX to MPEG-2, and as always, Toast fails miserably, blowing the video up in size, and because it can't handle the DIVX codec, causes very nasty pixelization.

Second you created a disc using ffmepgx to author,
and ffmepgx can handle DIVX more natively,and properly creates the video to size, with miminal work,
and the video is actually in its right spec
( for VBR standard Quality).
It created a UDF ( Univeral Disc Format) disc,
which as long as you have a valid VIDEO_TS folder,
the disc will burn fine in Toast, and will be playable
in a DVD Player.

i would do one of the following:

1.Convert the videos to QT movie files, so that
Toast will have less of a problem converting the files,
and use Toast to author if you are happy with it.

or

2. Author the files using ffmpegx, and as long as you are
happy with the way the files play before burning the disc,
continue authoring this way. You can test the files by playing
the VIDEO_TS folder in VLC.

[sstrungis]

Okay..Cool...I actually understood most of that.

I am not particularlly happy with Toast's quality. However, the original files are 480x360. I think that I will get pixelization no matter what encoder I use.

This still begs the question of how I end up with four episodes only taking up half a DVD when I author with Sizzle. Now that I know that the UDF file format seems to result in a watchable DVD disc, should I try getting 7 episodes on one disk? Will that fit or am I talking nonsense here?

The resulting mpg files are not playable in Quicktime. The disc image does mount and play in Apple's DVD player, so I assume that if I do burn it will not be a coaster.

I appreciate being able to encode on my Cube and only monopolize my wife's iMac when I am burning rather than waiting on Toast's slow re-encoding.

[thoughton]

The difference in size is due to different bitrate settings in Toast and ffmpegX. As far as I'm aware in Toast you dont have much control over the bitrate. In ffmpegX you do. However having said that ffmpegX will generally make a fair guess at the necessary bitrate so that you wont see much improvement by increasing it. (Although the method for calculating the optimum size using the ffmpeg encoder seems to have changed in the latest version of ffmpegX so it produces larger (and better quality) files than the last version). If you are already using the latest ffmpegX I'd go with its estimate and try for 6 or 7 episodes per disk.

PS The resultant mpg files are going to be mpeg2 files (normal for DVDs), which you cannot play in QuickTime unless you have the $20 (? maybe $25) QT mpeg2 playback component available from Apple. You should be able to play them in VLC though.