DIVX on DC!!!

TheBouncer · Post by **TheBouncer** » Wed Jan 16, 2002 3:39 am

The only problem is having to re-encode at a lower bit-rate but by my calculations it should be possible to fit 2 full length movies on 1 disc very easily and all this at a similar quailty to MPEG-1.

XenovipeR · Post by **XenovipeR** » Wed Jan 16, 2002 5:08 am

JustinVisible wrote: :p Im just thankful that I might be able to play my Divx disks on my dc,
My computer is too unstable to run them

u wouldnt be able to play those movies u got on ur DC either

cos i believe the movies u got are the ones u download off the net which r all dvd divx ... and res are quite high ... if u play thoses movies on ur DC it would be pretty much the same as u play on ur current slow PC

salvius · Post by **salvius** » Wed Jan 16, 2002 10:31 am

Yes, re-encoding is a problem. With Nandub (or now Gknot) it does take quite a bit for high quiality rendition. Not to mention re-encoding from Divx to Divx is an extremely lossy process.

fatheadpi · Post by **fatheadpi** » Thu Jan 17, 2002 5:20 pm

you know, I just had a thought. Maybe we could cut some of the quality loss if we did a 2 pass resize, wherein the first pass downsized the movie, and the second pass cut into the bitrate? If you did a 2 pass mode it would be a 3 pass process, but it could be worth it if you could noticibley cut quality losses.

salvius · Post by **salvius** » Thu Jan 17, 2002 11:39 pm

Yes, resize first definetely should make all that artifacting much better. I've never re-encoded Divx so I can't speak with complete assurance. Mpeg-1/2 encoders can do nearest-neigbour resize and bitrate encoding in one pass doing one first and then other. Works to same thing. However, any noise introduction still will be a considerable quality loss, especially if 300 kbs is the best they can do (not that I'm ungrateful). Personally, I don't mind re-ripping, but if you don't have access to originals that's without a doubt the way to do it.

I wish encoders worked more like the human eye.

fatheadpi · Post by **fatheadpi** » Fri Jan 18, 2002 4:25 pm

Okay I tried using VDub's filter to resize. I used one of the medium settings for quality, think precise bicubic. The redub cut the file size in half, but bitrate only got down to ~450 bps, so still about 75 bps higher than I'm currently aiming for. Since the origianl file was kinda fuzzy, I was surprised at the quality of the redub. It was about 95% of original, but it had that dv cam bootleg effect on certain parts of the file (where things seem just a bit blurred), will try again with higher filtering rates and lower bitrates.

fatheadpi · Post by **fatheadpi** » Fri Jan 18, 2002 4:26 pm

Oh also I forgot, I haven't been able to get vdub to do a pass where it just resizes the video, anyone gets this to work please let me know.

TheBouncer · Post by **TheBouncer** » Fri Jan 18, 2002 5:13 pm

I think it may be a good idea to create some sort of guide on how to re-encode Div-X files. If this Div-X player emerges, some people will be screaming, how do I do this? How do I do that? MPEG files are a doddle to re-encode, but Div-X seems to be a different ball game.

fatheadpi · Post by **fatheadpi** » Sat Jan 19, 2002 12:20 am

Yeah, I guess we could, wanna help this time too bouncer? I'm tinkerin with it a bit more, gonna see what I can get, looks like we can make 3 - 4 hour long movie discs.

Dr Wily · Post by **Dr Wily** » Sat Jan 19, 2002 9:47 am

um, if you have time and disk space to spare, I've found the easiest way to *just* resize a video without losing any bitrate is to convert it to an MPEG file, then resize, then re-encode into a DivX .avi

Yeah, it takes longer than simply re-encoding in Nandub / virtuaDub directly, but its slightly less lossy.

EDIT: also, to those complaining about getting 'lower quality' re-encodes from hi quality DivX files; unless you have an HDTV (which Im guessing most people dont) your TVs resolution is much less than a monitors (its like half the resolution), so anything downsized to like 320 x 240 will still look *extremely* high quality on a television...

DLolos · Post by **DLolos** » Sat Jan 19, 2002 10:52 am

How hi can HDTV's go? I remember something like 1900X1200 or somewhere around there. TVs can go up to 800X600 I think. If anyone has ripped a DVD movie you will see that not even DVD movies use 800X600. They use 720X480 or around there. I never remember the exact numbers for resolution.

Most people will rip a DVD movie using something like 640X240 if its almost 2 hours long. If it's like 1 hour and 45 minutes long I usual just leave it at 720X480. I now always use Two pass encoding. One pass just does not cut it. I'm surprised dcemulaiton talks about Divx since its like considered a format for piracy.

If this divx player can do 489X489 like the pocket divx can do then I'm happy with that. I wonder what the audio quality will need to be once its done. I keep seeing 22Khz audio? What will the bitrate need to be like 128 or 64 for mp3 audio? He also posts 30 fps video. What if I use 23.970 fps video? Can I use a higher resolution or better audio quality? These are question that keep going thru my head.

fatheadpi · Post by **fatheadpi** » Sun Jan 20, 2002 4:05 am

Look, as far as the average joe is concerned, 320x240 will probably look better than most vhs movies, especially if the source was a dvd. Stupid resolutions aside, I see some good questions have been raised. Divx is now talked about here because this is divx 4 based, not the illegal divx 3 based. Divx 4 is an indepent codec, divx 3 is a swipe off some of microsoft's mpeg 4 codecs.

For audio, with a 22 khz audio stream you could easily get away with a 64 kbps bandwidth, probably even less at that low of an audio resolution. If oyu are playing a 23.976 fps file, you would normally try to push more bitrate into the video, but in this case, I'd try and push the audio up to 24 or 32 khz as 22 khz audio is gonna be really really shitty (for example, ever downloaded, say, a movie where "everybody's hugging") and the audio was really really horrible and staticy? Same thing. I would set increased resolution as the lowest priority, then video bitrate, and audio bitrate most important.

TheBouncer · Post by **TheBouncer** » Sun Jan 20, 2002 5:18 am

fatheadpi: what were the best settings you found for use with GypPlay? I know you posted results of various settings, but what did u find to be the best?

Dr Wily · Post by **Dr Wily** » Sun Jan 20, 2002 10:43 am

For the record, I don't think DivX has ever been forbidden on the boards; in fact I think theres still probably the DivX codecs to download in the needed tools section... obviously links to DivX moviez isnt allowed, but general questions and stuff have been asked in Off Topic before (where they belong, at least until DCDivX gets a release)

TheBouncer: Just use the DC video settings file for TMPENC thats available to download... its the easiest way to get optimal VCD settings...

In terms of quality / playback / resolution I would expect DC DivX to be comparable to SVCD, if not slightly better, with the obvious advantage of being able to fit way more film on one CD

DLolos · Post by **DLolos** » Sun Jan 20, 2002 12:16 pm

Good point. At 320X240 with a bitrate of 300 and if the audio bitrate is like 64 then I could probably fit 3 movies on a single CD. Maybe with luck 4. Not to forget that DCDivx player is not even done yet so there could be new features and optimizations soon. It would really suck that the DC is less powerful then a Portable Pocket PC.

salvius · Post by **salvius** » Sun Jan 20, 2002 4:24 pm

Nyarlathotep, what the author is currently shooting for is not SVCD quiality, but comparable VCD quality. The resolution is not nearly as good, nor is the bitrate nearly enough. For book svcd quality, one would need a 480 x 480 Divx (well, something similar anyways) and about 500-600 kbs. This of course is SBC encoded and would rival 4 pass SVCD.

fatheadpi · Post by **fatheadpi** » Sun Jan 20, 2002 4:46 pm

I dunno if Divx ever was forbidden, we just never talked about it for a few reasons:

A. Gyplay Never supported Divx.

B. Previous attempts at dcdivx FAILED. HORRIBLY.

C. We made fun of people who brought up divx dc questions (or at least I think i did)

Bouncer, I got a post comin in a sec here with some gyplay notes.

Also, hey Dr. Z, any word on a DC multimedia section? I think everyone would be happy if I was confined to just one or two cubicles where nobody goes. Still have dibs on mod, and I called dibs, lmao.

Wicked Wizard · Post by **Wicked Wizard** » Sun Jan 20, 2002 9:47 pm

I think the divx player will be insane.I wouldn't mind the reincoding and shit, but my qhustion is, will you really be able to fit 3 to 4 whole movies in one disk.It sounds jut to good to be true and would be fabulous if it were.Other than that all my luck to the coders of the project.

ITS ALIVE!!! ITS ALIVE!!!

Wicked Wizard · Post by **Wicked Wizard** » Sun Jan 20, 2002 9:53 pm

One more thing , what's up with the "PLOP" thing. Don't you all have any balls, why the fuck (f#@k , just in case they replaced it with plop)can't you use those words, stop being suck fucken pussys, gay assed muthafuckers, other than that bulshit i can't wait till the player is out.

fatheadpi · Post by **fatheadpi** » Sun Jan 20, 2002 9:58 pm

Yes at these resolutions, I would expect to be able to fit around 4 - 6 hours of video on a cd, but as the quality improves, I think the final divx quality will end up at around 3 hours on one disc at negligibly less than dvd quality.

DIVX on DC!!!

3 MOVIES ON A DISK

PLOP