ffmpeg how to interpret parameters, documentation?

[BabaG]

i use ffmpeg frequently for fairly routine and simple tasks but have found my way into a corner that requires my understanding parameters i've not had to deal with before.

i'm told that ffmpeg currently only supports 10 bit dnxhr. i'm making 12 bit dnxhr, though. finding my way out of this corner will require a greater understanding, on my part, of the options ffmpeg provides. unfortunately, all of the documentation i've found so far either omits detailed explanation of parameters or assumes a prior knowledge of such. examples follow.

is there anything anywhere that explains what things like

yuv444p10le
yuv444p12le
yuv444p16le

actually mean? i can't find it explained anywhere. is this purely ffmpeg nomenclature or is it more widely used in the video world?

also, i'm getting stream info from ffprobe but don't know what some of the info produced means. example:

Stream #0:0(eng): Video: hqx (CHQX / 0x58514843), yuv422p16le(10 bpc, bt709, progressive)

i'm not sure what 10 bpc means or the relationship between 10 bpc and yuv422p16le. i'd love to find someplace that explains how to interpret all the info put out by ffprobe and ffmpeg.

thanks, babag

[davexnet]

Much of the English explanations can be found in the ffmpeg source member pixfmt.h
Here's a small section:

AV_PIX_FMT_YUV420P9BE, ///< planar YUV 4:2:0, 13.5bpp, (1 Cr & Cb sample per 2x2 Y samples), big-endian
    AV_PIX_FMT_YUV420P9LE, ///< planar YUV 4:2:0, 13.5bpp, (1 Cr & Cb sample per 2x2 Y samples), little-endian
    AV_PIX_FMT_YUV420P10BE,///< planar YUV 4:2:0, 15bpp, (1 Cr & Cb sample per 2x2 Y samples), big-endian
    AV_PIX_FMT_YUV420P10LE,///< planar YUV 4:2:0, 15bpp, (1 Cr & Cb sample per 2x2 Y samples), little-endian
    AV_PIX_FMT_YUV422P10BE,///< planar YUV 4:2:2, 20bpp, (1 Cr & Cb sample per 2x1 Y samples), big-endian
    AV_PIX_FMT_YUV422P10LE,///< planar YUV 4:2:2, 20bpp, (1 Cr & Cb sample per 2x1 Y samples), little-endian
    AV_PIX_FMT_YUV444P9BE, ///< planar YUV 4:4:4, 27bpp, (1 Cr & Cb sample per 1x1 Y samples), big-endian
    AV_PIX_FMT_YUV444P9LE, ///< planar YUV 4:4:4, 27bpp, (1 Cr & Cb sample per 1x1 Y samples), little-endian
    AV_PIX_FMT_YUV444P10BE,///< planar YUV 4:4:4, 30bpp, (1 Cr & Cb sample per 1x1 Y samples), big-endian
    AV_PIX_FMT_YUV444P10LE,///< planar YUV 4:4:4, 30bpp, (1 Cr & Cb sample per 1x1 Y samples), little-endian
    AV_PIX_FMT_YUV422P9BE, ///< planar YUV 4:2:2, 18bpp, (1 Cr & Cb sample per 2x1 Y samples), big-endian
    AV_PIX_FMT_YUV422P9LE, ///< planar YUV 4:2:2, 18bpp, (1 Cr & Cb sample per 2x1 Y samples), little-endian
    AV_PIX_FMT_VDA_VLD,    ///< hardware decoding through VDA

10 bpc means bits per channel, while BT709 refer to the color space. Much more technical explanations can be found on the net

[BabaG]

wow! thanks, davexnet. very interesting. is there nowhere else, other than buried in source code, that someone might find such documentation? also, i had guessed that bpc was something like bits per channel. thanks for the confirmation on that. i see a lot of bpp references in the file you referenced. i'm guessing that's bits per pixel? is there nowhere that has a comprehensive listing of such definitions?

thanks again,
BabaG