View Full Version : DVD2SVCD Suggestion: encoding by chapter-based work units?


isolationism
26th February 2002, 06:35
Well, I'm sure you hear this sob story often enough, but CCE tends to be somewhat crashy on one of my machines -- no clue why. The worst part is, it loves to work normally for a good 2-3 hours of encoding then bluescreens without warning, even though it's not being used at all. I know it's not the fault of your application. I had a thought, though. Hear me out?

What about adding a flag which essentially allows you to rip a series of chapters or entire disc, using the internal ripping routines already included -- but then, one chapter at a time, extract and transcode the audio, encode the video, pulldown and mux it all as one work unit?

That way it's much less frustrating if a video encode crashes 2/3 of the way through the job, since the average job would be only 3-10 minutes' worth of video (for a chapter) rather than 100-140 minutes' worth for an entire movie in one shot. Then use BBMPEG (or similar app) to stitch them all together at the end.

There are a few other practical upshots besides the reduced losses due to CCE crashing, too. First, those on slower machines could interrupt the process if it's not completed by morning when they need their computers back, and use the resume feature to continue it later (as the log file would track the work units completed). They'd have only lost a maximum of one chapter's worth of encoding.

Second, and more enticingly, this might also make it possible to make the discs divide cleanly between chapter breaks, for those who prefer to have a cleaner transition between discs (versus stacking each disc to it's maximum capacity).

Third, it could even lead to the potential for the truly anal to tinker with the application and maybe even select different bitrates for each chapter, depending on the amount of motion or whatever. There are a lot of possibilities for experimentation and further controlled refinement of the process if a work unit wasn't a solid 7-9 hour job to encode the video.

I apologise if this has been offered before. It just struck me today as being a great idea to be able to divide the work up for a single video, as I have three able machines here to do a video, and so have been using each PC to create one disc out of a three-disc encode (by selecting which chapters each would handle manually).

Thanks again for the great software and all of your time.

DDogg
26th February 2002, 07:14
Wouldn't it be easier for folks with CCE problems to just use the new TMPG 2 pass vbr or CQ support in the latest version?

pacohaas
26th February 2002, 07:29
Originally posted by isolationism
Third, it could even lead to the potential for the truly anal to tinker with the application and maybe even select different bitrates for each chapter, depending on the amount of motion or whatever.I believe this is how it works currently with VBR in CCE and TMPG. That's the whole point of the multi-passes.

But still, I can see where those who don't have a 3-disc changer :D would want more control over where the images are cut.

isolationism
26th February 2002, 07:52
Originally posted by pacohaas
I believe this is how it works currently with VBR in CCE and TMPG. That's the whole point of the multi-passes.


To some extent, yes. But you still have a maximum, minimum and average bitrate that is set -- these numbers could still be adjusted from scene to scene. I know it's anal, but the bitrate of DVDs can vary widely from scene to scene for exactly this reason -- efficiency when the bits aren't needed, and quality when they are. Anyway, the more obvious point you're missing is that there are plenty of folk who prefer to do a single-pass CBR encode for the sake of speed. They currently don't have the ability to change that CBR anywhere throughout the movie; they're stuck with however many bits they assign whether they're watching talking heads or whip-panned airplanes surrounded by fireballs, from chapter to chapter.

Originally posted by pacohaas
But still, I can see where those who don't have a 3-disc changer :D would want more control over where the images are cut.

I own a 3-disc changer; it doesn't make it any less annoying when someone gets cut off in the middle of a sentence, or in mid-action sequence (the Lord of the Rings screener that's been going around made me want to tear my eyelashes out for precisely this reason). Unlike whoever released that video, I leave a nice 10 second overlap between discs, but I still find it's even nicer to be able to make the disc change on a chapter division.

If you went to the cinema and were watching a long movie that required two reels, would you want the intermission to start in the middle of a sentence -- even if it was repeated for you at the beginning of the next reel -- or would you want it to be between a logical division in scenes and plot?