[MPlayer-users] -ss Does it work? Also bpp. Bunkus explain maybe?

[Geoffrey Trexler]

Does the start position (-ss) work? I'll show you the options I'm using.

cat *.vob | nice -+19 mencoder -aid 128 -oac mp3lame -lameopts vbr=3:br=128 -ofps 23.976 -ovc lavc -lavcopts vcodec=mpeg4:vhq:vbitrate=1608:vqmin=2:vqmax=31:vpass=1 -vop scale=528:-2 -ss 00:00:21 -endpos 01:55:50 -; cat *.vob | nice -+19 mencoder -aid 128 -oac mp3lame -lameopts vbr=3:br=128 -ofps 23.976 -ovc lavc -lavcopts vcodec=mpeg4:vhq:vbitrate=1608:vqmin=2:vqmax=31:vpass=2 -vop scale=528:-2 -ss 00:00:21 -endpos 01:55:50 -

Ok about the bits per pixel. I put this in:  perl ../../calcbpp.pl 720x466 1.78 1608 29.97

Prescaled picture: 1025x466, AR 2.20
720x320, diff   7, new AR 2.25, AR error 2.21% scale=720:320 bpp: 0.233
704x320, diff   0, new AR 2.20, AR error 0.01% scale=704:320 bpp: 0.238
688x320, diff  -7, new AR 2.15, AR error 2.33% scale=688:320 bpp: 0.244
672x304, diff   1, new AR 2.21, AR error 0.47% scale=672:304 bpp: 0.263
656x304, diff  -6, new AR 2.16, AR error 1.96% scale=656:304 bpp: 0.269
640x288, diff   3, new AR 2.22, AR error 0.99% scale=640:288 bpp: 0.291
624x288, diff  -4, new AR 2.17, AR error 1.55% scale=624:288 bpp: 0.299
608x272, diff   4, new AR 2.24, AR error 1.57% scale=608:272 bpp: 0.324
592x272, diff  -3, new AR 2.18, AR error 1.09% scale=592:272 bpp: 0.333
576x256, diff   6, new AR 2.25, AR error 2.21% scale=576:256 bpp: 0.364
560x256, diff  -1, new AR 2.19, AR error 0.58% scale=560:256 bpp: 0.374
544x240, diff   7, new AR 2.27, AR error 2.93% scale=544:240 bpp: 0.411
528x240, diff   0, new AR 2.20, AR error 0.01% scale=528:240 bpp: 0.423
512x240, diff  -7, new AR 2.13, AR error 3.13% scale=512:240 bpp: 0.437
496x224, diff   1, new AR 2.21, AR error 0.64% scale=496:224 bpp: 0.483
480x224, diff  -6, new AR 2.14, AR error 2.67% scale=480:224 bpp: 0.499
464x208, diff   3, new AR 2.23, AR error 1.37% scale=464:208 bpp: 0.556
448x208, diff  -4, new AR 2.15, AR error 2.15% scale=448:208 bpp: 0.576
432x192, diff   4, new AR 2.25, AR error 2.21% scale=432:192 bpp: 0.647
416x192, diff  -3, new AR 2.17, AR error 1.55% scale=416:192 bpp: 0.672
400x176, diff   6, new AR 2.27, AR error 3.19% scale=400:176 bpp: 0.762
384x176, diff  -1, new AR 2.18, AR error 0.84% scale=384:176 bpp: 0.794
368x160, diff   7, new AR 2.30, AR error 4.34% scale=368:160 bpp: 0.911
352x160, diff   0, new AR 2.20, AR error 0.01% scale=352:160 bpp: 0.953
336x160, diff  -7, new AR 2.10, AR error 4.77% scale=336:160 bpp: 0.998
320x144, diff   1, new AR 2.22, AR error 0.99% scale=320:144 bpp: 1.164

I don't really understand what all this means. For example diff -4 ???, and AR error ??? Could someone explain this in detail to me?

I'm trying to encode a good DVD Quality Spiderman onto two 700MB CD's. That's my goal. It looks really nice in the low motion scenes with the settings I have above, however in the high motion scenes it doesn't look that great. BTW the movie is 121 minutes long, but I'm going to cut some of it, which is why I'm trying to get the -ss to work. So it should turn out to be about 115 minutes long. Maybe this will help in your calculations.