Default Pixel Format For FFMPEG For Encoding an Image Stack To Movie -


if 1 converting stack of images .mp4 ffmpeg using libx264 encode h.264 video , 1 didn't specify pixel format in call ffmpeg default pixel format yuvj420? i've been doing experiments , have been getting results identical if specified yuvj420 format versus if specify no format.

output pixel format depends on input pixel format, encoder being used, , if performing filtering.

according ffmpeg -h encoder=libx264 encoder supports following pixel formats: yuv420p yuvj420p yuv422p yuvj422p yuv444p yuvj444p nv12 nv16 nv21.

by default ffmpeg automatically perform pixel format conversion 1 of supported formats: whichever resembles source pixel format. can increase verbosity of console output see in more detail using -loglevel debug. example rgb24 input:

[format @ 0x55657882d6e0] compat: called args=[yuv420p|yuvj420p|yuv422p|yuvj422p|yuv444p|yuvj444p|nv12|nv16|nv21] [format @ 0x55657882d6e0] setting 'pix_fmts' value 'yuv420p|yuvj420p|yuv422p|yuvj422p|yuv444p|yuvj444p|nv12|nv16|nv21' [format @ 0x55657882d6e0] auto-inserting filter 'auto_scaler_0' between filter 'parsed_null_0' , filter 'format' [auto_scaler_0 @ 0x55657882eb00] picking yuv444p out of 8 ref:rgb24 alpha:0 [auto_scaler_0 @ 0x55657882eb00] w:320 h:240 fmt:rgb24 sar:1/1 -> w:320 h:240 fmt:yuv444p sar:1/1 flags:0x4

example force pixel format output: -vf format=yuv420p or -pix_fmt yuv420p.


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