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I kept having trouble encode videos. I can encode the video to mpg but the size is 10+x bigger (no joke).

So i thought i'd do something simple. Strip the sound, copy the video

ffmpeg -i 5.flv -vcodec copy -an 5o.flv

It couldnt do that! note that it can produce a very large mpg file and videolan can play it. However theres no keyframes so i can jump. It was produced by copying a stream. Results are...

FFmpeg version 0.5, Copyright (c) 2000-2009 Fabrice Bellard, et al.
  configuration: --enable-gpl --enable-postproc --enable-swscale --enable-avfilt
er --enable-avfilter-lavf --enable-pthreads --enable-avisynth --enable-libfaac -
-enable-libfaad --enable-libmp3lame --enable-libspeex --enable-libtheora --enabl
e-libvorbis --enable-libxvid --enable-libx264 --enable-memalign-hack
  libavutil     49.15. 0 / 49.15. 0
  libavcodec    52.20. 0 / 52.20. 0
  libavformat   52.31. 0 / 52.31. 0
  libavdevice   52. 1. 0 / 52. 1. 0
  libavfilter    0. 4. 0 /  0. 4. 0
  libswscale     0. 7. 1 /  0. 7. 1
  libpostproc   51. 2. 0 / 51. 2. 0
  built on Mar 16 2009 16:09:18, gcc: 4.2.4 [Sherpya]
Input #0, flv, from '5.flv':
  Duration: N/A, start: 0.000000, bitrate: N/A
    Stream #0.0: Video: flv, yuv420p, 320x240, 1k tbr, 1k tbn, 1k tbc
    Stream #0.1: Audio: nellymoser, 11025 Hz, mono, s16
File '5o.flv' already exists. Overwrite ? [y/N] y
Output #0, flv, to '5o.flv':
    Stream #0.0: Video: flv, yuv420p, 320x240, q=2-31, 90k tbn, 1k tbc
Stream mapping:
  Stream #0.0 -> #0.0
Press [q] to stop encoding
[NULL @ 0x16a4010]error, non monotone timestamps 1571775 >= 11811
av_interleaved_write_frame(): Error while opening file


The file ends at 716kb (of 8.9mb). So it has started, it just had problems. How can i tell it to ignore errors or fix this?

share|improve this question
you want to remove only the audio part of the input files? are you forced to use ffmpeg (for whatever reasons)? – akira Sep 27 '09 at 7:15

Suggest checking out Handbrake.
Its available for Windows and Unix (Ubuntu).
For Ubuntu, try directly on synaptic.

Here is a ffmpeg cheatsheet reference and a detailed howto, if you want to get deeper into ffmpeg.

You command seems to suggest a FLV input file...
Can you run the source file through GSpot 2.70a and describe the encoding a bit more?
Handbrake usually works quite well in picking up standard formats for conversions.

share|improve this answer
and by using handbrake (which uses libav* ... -> ffmpeg) ... which part of the question is solved? – akira Sep 27 '09 at 7:13
@akira, I interpreted the primary problem as a need for translating a larger video to a smaller size. Handbrake has very simple profiles to get this done. However, If the OP is interested in learning ffmpeg details to get things done (or figure out what cannot be done), I gave some other references. – nik Sep 27 '09 at 7:20
Handbrake gave me problems too. I couldnt encode the video to ANYTHING with handbreak – acidzombie24 Sep 27 '09 at 16:21
as i said: handbrake is based on ffmpeg libraries, which means that if one does not solve the underlying problem of the input file .. nothing solid gets out of anything. – akira Sep 27 '09 at 19:05
@akira, and you are quite right. But, sometimes solving the ffmpeg options is in-itself quite an involved task. – nik Sep 27 '09 at 19:17

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