[MPlayer-users] Re: Tools for mpeg* to DVD

[Danny Bogaards]

Hi,

I tried using ffmpeg instead of mpeg2enc as was suggested in this thread, 
but I found a number of problems. I'm not talking about speed differences, 
because I haven't disabled interlacing and B-frames on mpeg2enc to 
actually compare. I just look at the resulting mpeg2 file and see the 
results in mplayer and when burned to dvd.

encoder with ffmpeg, mplex reports:
INFO: [mplex] No. Pictures    :    53199
INFO: [mplex] No. Groups      :     4488
INFO: [mplex] No. I Frames    :     4488 avg. size 57618 bytes
INFO: [mplex] No. P Frames    :    48711 avg. size 21984 bytes
INFO: [mplex] No. B Frames    :        0 avg. size     0 bytes
INFO: [mplex] No. D Frames    :        0 avg. size     0 bytes
INFO: [mplex] Average bit-rate :  4998000 bits/sec
INFO: [mplex] Peak bit-rate    : 10440400  bits/sec

and mplayer reports:
VIDEO:  MPEG2  720x576  (aspect 1)  25.000 fps    0.0 kbps ( 0.0 kbyte/s)

encoder with mpeg2enc, mplex reports:
INFO: [mplex] No. Pictures    :    53199
INFO: [mplex] No. Groups      :     3561
INFO: [mplex] No. I Frames    :     3561 avg. size 43648 bytes
INFO: [mplex] No. P Frames    :    14189 avg. size 26212 bytes
INFO: [mplex] No. B Frames    :    35449 avg. size 18709 bytes
INFO: [mplex] No. D Frames    :        0 avg. size     0 bytes
INFO: [mplex] Average bit-rate :  4476000 bits/sec
INFO: [mplex] Peak bit-rate    :  4949600  bits/sec

and mplayer says:
VIDEO:  MPEG2  720x576  (aspect 2)  25.000 fps  5000.0 kbps (625.0 kbyte/s)

Both sessions where encoded with:
-w 5000 --video_max_bitrate 8000 -export_asr 2

So I see three problems, the maximum bitrate is not as requested 
(8000kbps), the aspect ratio is not right and mplayer can't 'gues' the 
bitrate. The average bitrate is very accurate with ffmpeg though.....

Must be a header problem? Or must I use extra parameters when using ffmpeg?

The loolame hint didn't work for me. I have to resample from 44100 to 
48000. Toolame uses sox for that and the result was slightly slower as 
with mp2enc. Are there maybe other arguments to switch to toolame?

Danny