-sb can not be used with AVI files

[egor@…]

mencoder -ovc copy -nosound -sb 3500000000 -endpos 15 -o result.avi test.avi

Error message:
MEncoder 2:1.0~rc2-0ubuntu1~gutsy1 (C) 2000-2007 MPlayer Team
CPU: AMD Athlon(tm) 64 X2 Dual Core Processor 5200+ (Family: 15, Model: 67, Stepping: 3)
CPUflags: Type: 15 MMX: 1 MMX2: 1 3DNow: 1 3DNow2: 1 SSE: 1 SSE2: 1
Compiled with runtime CPU detection.
success: format: 0 data: 0x0 - 0x9eba413e
============ Sorry, this file format is not recognized/supported =============

If this file is an AVI, ASF or MPEG stream, please contact the author!

Cannot open demuxer.

Exiting...

output of the 'file test.avi':
RIFF (little-endian) data, AVI, 720 x 576, 25.00 fps, video:, audio: uncompressed PCM (stereo, 48000 Hz)

on the other hand, this command works fine:
mencoder -sws 9 $CROP,pullup,softskip,scale=480:-10,harddup,unsharp=l3x3:0.7,expand=480:272 -ofps 24000/1001 -oac faac -faacopts br=128:mpeg=4:object=2:raw -ovc x264 -x264encopts bitrate=650:global_header:partitions=all:trellis=1:vbv_maxrate=768:vbv_bufsize=2000:level_idc=30:threads=4 -of lavf -lavfopts format=psp -o $2.MP4 $1;

the source file test.avi was created with mencoder from a DVD with -oac pcm.

[reimar]

you can not use -sb this way, it makes MPlayer/mencoder completely ignore the first bytes of the file, which for AVI also means it cannot find the file header.
Mostly -sb only works for MPEG streams.