从.mov转换为mp4文件时，ffmpeg中的-pix_fmt发生错误

Question

I am trying to convert .mov to .mp4 using ffmpeg my command is :

ffmpeg -i input.mov -vcodec libx264 -acodec copy output.mp4

but its giving me error like this

    [buffer @ 00000000059bf480] Unable to parse option value "-1" as pixel format
Last message repeated 1 times

[buffer @ 00000000059bf480] Error setting option pix_fmt to value -1. [graph 0 input from stream 0:4 @ 00000000043fd8a0] Error applying options to the filter. Error opening filters!

even I tried for another command

ffmpeg -i input.mov -vcodec copy -acodec copy output.mp4

but it converts only some part and first part is blank with sound then after some time picture is coming..

I have two Q's

1] for first command what is -pix_fmt and what value to be set for ?

2] for second command why it was giving only some part, as I am copying everything vcodec as well acodec..

please guide me ..!!

Answer 1

Probably, selected profile does not support 4:2:2.

So, you need to mention the 4:2:0 by adding "-pix_fmt yuv420p" to the command.

Hope this will fix it.

Answer 2

FFmpeg's "Unable to parse option value '-1' as pixel format" does occur with corrupted or harder to parse videos (although doubted on the mailing list). I've had it, and the best comment on that is to try increasing analyzeduration - as in this ticket . Some ffmpegs/ avconvs also give a note about tinkering with probesize:

Could not find codec parameters for stream 0 (Video: h264 (avc1 / 0x31637661), none, 720x576, 869 kb/s): unspecified pixel format Consider increasing the value for the 'analyzeduration' and 'probesize' options

Well, both didn't work on a file where I tried it:

[mov,mp4,m4a,3gp,3g2,mj2 @ 0x2c36940] multiple edit list entries, a/v desync might occur, patch welcome [mov,mp4,m4a,3gp,3g2,mj2 @ 0x2c36940] max_analyze_duration 5000000 reached

but other people's mileage may vary.