[MPlayer-users] MEncoder and file sizes

[Robinson, Chad]

Well, I finally got mencoder to compile, after reinstalling with the latest
version of Slackware. Looks very good, and thank you for this - I got a
1.8GB MPEG camcorder file down to around 800MB with this.

However, I'm having a bit of a problem. I have a bunch of half-hour,
VCD-ready MPEG files at around 220MB each. When I run Mencoder on them,
surprise surprise - they get LARGER! I've tried:

Source file:
-rw-r--r--    1 root     root     229271896 Nov 15 11:27 507.mpg

/usr/bin/time mencoder 507.mpg -v -ovc divx4 -oac mp3lame -divx4opts br=1500
-lameopts br=128 -o 507.avi -pass 1
/usr/bin/time mencoder 507.mpg -v -ovc divx4 -oac mp3lame -divx4opts br=1500
-lameopts br=128 -o 507.avi -pass 2
-rw-r--r--    1 root     root     271905282 Nov 15 12:54 507.avi

/usr/bin/time mencoder 507.mpg -v -ovc divx4 -oac mp3lame -divx4opts br=1500
-lameopts br=128 -o 507b.avi
-rw-r--r--    1 root     root     271280666 Nov 15 13:24 507b.avi

/usr/bin/time mencoder 507.mpg -v -ovc divx4 -oac mp3lame -divx4opts br=1100
-lameopts br=128 -o 507c.avi
-rw-r--r--    1 root     root     211615938 Nov 15 14:17 507c.avi

I extracted a piece of output from one of these attempts below, for your
reference:

==> Found video stream: 0
Detected MPEG-PS file format!
==> Found audio stream: 0
Searching for sequence header... OK!
VIDEO:  MPEG1  352x240  (aspect 12)  29.97 fps  1437.5 kbps (179.7 kbyte/s)
[V] filefmt:2  fourcc:0x10000001  size:352x240  fps:29.97  ftime:=0.0334
Detected video codec: [mpeg12] drv:1 (MPEG 1 or 2)
mpeg2dec-0.2.0-release (C) 2000-2001 Aaron Holtzman & Michel Lespinasse
libmpeg2: Using MMXEXT for IDCT transform
libmpeg2: Using MMXEXT for motion compensation
Detected audio codec: [mp3] drv:1 (MPEG layer-2, layer-3)
Initializing audio codec...
dec_audio: Allocating 4608 + 65536 = 70144 bytes for output buffer
mp3lib: Processor ID: 68a
mp3lib: Using SSE! optimized decore.
AUDIO: srate=44100  chans=2  bps=2  sfmt=0x10  ratio: 28000->176400

Any thoughts? I can understand the increase for the higher bitrate, but
wasn't expecting the almost non-existent decrease given the same bitrate.
(The only reason I tried the higher bitrate was because it was an automated
script that uses the same bitrate for all files.)

Regards,
Chad