Unable to decode an MXF video

[rajivrp]

Hi,

Am trying to convert an MXF video into any other format (tried f4v, wmv, mov so far), but it's failing with the same error, looks like it's unable to decode the input file -

ffmpeg.exe -i C:\Samples\admintest_mxf.mxf -f avm2 "Output.f4v"

ffmpeg version N-35462-g61b1d85, Copyright (c) 2000-2011 the FFmpeg developers
built on Dec 5 2011 14:22:27 with gcc 4.6.2
configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-ru
ntime-cpudetect --enable-avisynth --enable-bzlib --enable-frei0r --enable-libope
ncore-amrnb --enable-libopencore-amrwb --enable-libfreetype --enable-libgsm --en
able-libmp3lame --enable-libopenjpeg --enable-librtmp --enable-libschroedinger -
-enable-libspeex --enable-libtheora --enable-libvo-aacenc --enable-libvo-amrwben
c --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --enable-
libxvid --enable-zlib
libavutil 51. 30. 0 / 51. 30. 0
libavcodec 53. 40. 0 / 53. 40. 0
libavformat 53. 24. 0 / 53. 24. 0
libavdevice 53. 4. 0 / 53. 4. 0
libavfilter 2. 51. 0 / 2. 51. 0
libswscale 2. 1. 0 / 2. 1. 0
libpostproc 51. 2. 0 / 51. 2. 0

Input #0, mxf, from 'C:\Samples\admintest_mxf.mxf':
Duration: 00:00:57.05, start: 0.000000, bitrate: 42599 kb/s
Stream #0:0: Video: mpeg2video (4:2:2), yuv422p, 720x512 [SAR 128:135 DAR 4:
3], 30000 kb/s, 29.97 fps, 29.97 tbr, 29.97 tbn, 59.94 tbc
Stream #0:1: Audio: pcm_s16le, 48000 Hz, 8 channels, s16, 6144 kb/s
Incompatible pixel format 'yuv422p' for codec 'flv', auto-selecting format 'yuv4
20p'
[buffer @ 03CBAEA0] w:720 h:512 pixfmt:yuv422p tb:1/1000000 sar:128/135 sws_para
m:
[buffersink @ 03CBAF40] auto-inserting filter 'auto-inserted scale 0' between th
e filter 'src' and the filter 'out'
[scale @ 03C66E80] w:720 h:512 fmt:yuv422p -> w:720 h:512 fmt:yuv420p flags:0x4
[libmp3lame @ 03C672A0] Invalid number of channels 8, must be <= 2

Output #0, avm2, to 'Output.f4v':
Stream #0:0: Video: flv1, yuv420p, 720x512 [SAR 128:135 DAR 4:3], q=2-31, 20
0 kb/s, 90k tbn, 29.97 tbc
Stream #0:1: Audio: mp3, 48000 Hz, 8 channels, s16, 128 kb/s
Stream mapping:
Stream #0:0 -> #0:0 (mpeg2video -> flv)
Stream #0:1 -> #0:1 (pcm_s16le -> libmp3lame)
Error while opening encoder for output stream #0:1 - maybe incorrect parameters
such as bit_rate, rate, width or height

I just realize the source file is of video codec MXF OP1a - IMX 30 ..... is it supported by FFMpeg ??

Thanks,
Rajiv

[poisondeathray]

The problem is the audio , not the video or container (8 mono channel configuration isn't supported by MP3)

You should downmix to stereo . See this (it refers to ffmbc, but you should be able to do it with ffmpeg as well)

https://forum.videohelp.com/threads/335877-FFmpeg-FFmbc-8-Mono-track-to-1-Stereo
http://ffmbc.wordpress.com/category/audio/

[rajivrp]

Thank you ...

I will do some research how to do it with FFMpeg, if anyone knows the command, pls do share ...

Rajiv

[Case]

I will do some research how to do it with FFMpeg, if anyone knows the command, pls do share ...

Add -ac 2 to your command line.
"-ac 2" specifies that the output will have two audio channels.

[rajivrp]

Thanks a lot !!