problems with mencoder for video compatibility with Sansa e250

zach014 · 06-27-2007, 12:03 PM

I found a mencoder script online to resize, change the frame rate, the rotation, change it to 420p, change it to grayscale, and change the file type in order for it to be playable on a Sandisk Sansa e250.
However, when i run this script, it tells me constantly that it is skipping a frame. When i remove the -ofps argument it goes fine, but in both instances when I open the resulting *.mov, it doesn't show any video. The audio works fine though. Here is the script:

Code:

#!/bin/bash
mencoder -ofps 15 -vf rotate=1,scale=160:208 -ffourcc mjpb -ovc lavc -lavcopts vcodec=mjpeg:vbitrate=150:vhq:gray -oac pcm -srate 11025 -of lavf -lavfopts i_certify_that_my_video_stream_does_not_use_b_frames futurama-12.mpg -o /tmp/video.mov
ffmpeg -i /tmp/video.mov -vcodec copy -acodec pcm_s16be futurama-12.mov
rm -f /tmp/video.mov

thanks in advance
~zach

EDIT (10:15 AM, JULY 17):
ok after trying each section of this code, i figured out that the problem was the section:

Code:

-ffourcc mjpgb

it wouldn't play in xine or mplayer when i converted it to MJPEG-B format
it also didnt work in the Sansa
is there some other way to convert it to MJPEG-B format, or perhaps some codecs i need?

Samotnik · 06-28-2007, 05:07 AM

Try to play resulting video with $ mplayer -identify -v futurama-12.mov and grep output for all critical parameters (container format, video codec, video bitrate, audio codec, audio samplerate, dimensions etc.) to be the same as needed by your player.

zach014 · 07-17-2007, 09:12 AM

YES! a solution!
the script was a bit iffy
so here's the new one:

Code:

#!/bin/bash
INPUT="apple-getamac-fat_480x376.mov"
OUTPUT="apple-fat"
mencoder $INPUT -o /tmp/output.mov -oac pcm -af resample=11025 -ovc lavc -lavcopts vcodec=mjpeg:gray -ffourcc mjpa -vf rotate=1,scale=176:220 -ofps 12 -of lavf -lavfopts i_certify_that_my_video_stream_does_not_use_b_frames
ffmpeg -i /tmp/output.mov -vcodec copy -acodec pcm_s16be $OUTPUT.mov
rm -f /tmp/output.mov

reddazz · 07-17-2007, 08:00 PM

zach014 we do not routinely delete threads or posts except in very exceptional circumstances. If your problem has been resolved, the thread is just kept as it is. Cheers.

frenchn00b · 07-27-2007, 07:15 PM

Nice thread.

I used this as "copy" mode & rotation :

Code:

mencoder /tmp/input.mov  -o /tmp/output.avi -oac pcm  -ovc lavc -vf rotate=1

zach014 · 07-31-2007, 09:54 AM

yep these scripts are all very well but for the color problem
so i just put rockbox on my e250 instead
rockbox.org