New Compiled ffmpeg

[luttrell1962]

I've compiled my own copy of ffmpeg-0.5. It is twice as fast as my earlier version. I was only getting 60fps converting 1080i to 720p but now am getting over 120fps. This is a experimental build. It has xvid, libmp3lame, libx264, faac built in. It gets avcodec alignment errors when ran but still works. I'm going to recompile it with gcc version 4.2 or higher to get rid of the errors. It uses pthreads instead of win32 threads. I think that is why it is faster. Xvid is really slow on my machine only giving about 16fps. I'll stick with 2 pass mpeg4 conversion.

I'll put it into production tonight to work on a few files.

If you want to play with it you can download it from
http://www.mediafire.com/?an3iyoitttt

[luttrell1962]

After some extra testing it's faster on some files but just a little on others. On HDMI pillerbox it's just a little bit faster but full screen video it seems a lot faster.

I can't get it to compile under gcc 4.2.1, but am working on the problem. There's also compiler optimizations to look at. I have not done any compiling in years so have to relearn it all. I'm using mingw and msys. Lots of problems. Might convert over to cygwin,

First impression is quality is better than the .18695 version I was using

[mvallevand]

Here is one source of ffmpeg nightlies, some are good some are not so good.

http://ffmpeg.arrozcru.org/autobuilds/

Martin

[luttrell1962]

I can't seem to duplicate the 120fps. Now on files I get 38-40fps converting to 1280x720. 60fps converting native resolution. I've noticed single pass vbr is much better quality. So no need to do a 2 pass.

I've got decent quality using qmax 7 with vbr set to 2500k 720p. Small file 2 and half men is 646megs and not bad quality. I noticed if I set qmax to 6 vbr jumps to 3000k 5 to 3500-4000k.

I can get native resolution to 4500kbitrate but not so good with qmax 10

Code:

"D:\Program Files (x86)\Devnz\GBPVR\Third Party\ffmpeg\ffmpeg.exe" -y -i "%~dp1%~n1.m2v" -i "%~dp1%~n1.ac3" -ab 128k -acodec libmp3lame -ac 2 -async 1 -ar 44100 -f avi -qmax 7 -threads 8 -s 1280x720 -b 2500k -minrate 0k -maxrate 10000k -vcodec mpeg4 -bufsize 1000k -vtag divx %

I do a file split before conversion to correct frame and time line errors as the m2v and ac3 input files.

[luttrell1962]

I'm converting Harry Potter and the Prisoner of Azkaban and getting fps of 160. I analyzed the ts file and it was transmitted in 720p. So this explains the difference in frame rates during conversion.

[luttrell1962]

I've been playing with converting using xvid instead of mpeg4. With mpeg4 it seems that some backgrounds are really blocky looking. When I use xvidlib backgrounds do not look that way. Face's don't seem as sharp but acceptable.

Xvid is slower though but with the multiconv program I wrote that is not an issue since I can run 3 instances at the same time.

It's strange, with the mpeg4 codec @ 720p bitrate 3000k or better 4:3 video does not convert as well as 16x9. Seems that it should be better since the black bars on the side don't take up much bit rate.

At the moment I used 2000k btr with 800x450 this is proportional to 1080i 720p. I'm currently trying 1600k to see how that looks.

[luttrell1962]

I just encoded my name is earl with bitrate set to 1600k but it encoded at about 1750k Xvid. Really decent quality, a little better than dvd and filesize is only 400megs. 1/2 hour. I've played around with mpeg4 for about a month now and could never get it to be acceptable to me. I used my compiled fflmpeg

Code :

Code:

"D:\Program Files (x86)\Devnz\GBPVR\Third Party\ffmpeg\ffmpeg.exe" -y -i (video filename) -an -r 29.97 -f avi -threads 8 -s 800x450 -b 1600k -qmin 3 -qmax 8 -pass 1 -minrate 0k -maxrate 10000k -vcodec libxvid -bufsize 3500k -vtag xvid nul
"D:\Program Files (x86)\Devnz\GBPVR\Third Party\ffmpeg\ffmpeg.exe" -y -i (video filename) -ab 128k -acodec libmp3lame -ac 2 -r 29.97 -async 1 -ar 44100 -f avi -threads 8 -s 800x450 -b 1600k -qmin 3 -qmax 8 -pass 2 -minrate 0k -maxrate 10000k -vcodec libxvid -bufsize 3500k -vtag xvid %2

Edit : some bug cropped up when I started to convert startrek the next generation 4:3 the conversion bombed, but not sure why yet.

[luttrell1962]

The problem turned out that ffmpeg only deviates a certain amount from the -b baserate. Even though I set maxrate really high. It seems to ignore that. Once I set the bitrate to 1800k I was able to encode several more files without problem.

I have been testing 720p resolution but it is so slow 14fps on both passes. I know that you can use -vpre -fpre with the ffpresets but there are none for Xvid. Would like to speed up the first pass since it takes 2+ hours to just encode 1/2 hour.

Here are some options for Xvid
http://www.mplayerhq.hu/DOCS/HTML/en/men...-xvid.html
But I wonder how I set them, the site doesn't even give defaults.