Function avmScaleQuantizer

src/codec_avm.c:406–416

Scales from aom's [0:63] to avm's [M:255], where M=0/-48/-96 for 8/10/12 bit. See --min-qp help in https://gitlab.com/AOMediaCodec/avm/-/blob/main/apps/avmenc.c

// See --min-qp help in
// https://gitlab.com/AOMediaCodec/avm/-/blob/main/apps/avmenc.c
static int avmScaleQuantizer(int quantizer, uint32_t depth)
{
    if (depth == 10) {
        return AVIF_CLAMP((quantizer * (255 + 48) + 31) / 63 - 48, -48, 255);
    }
    if (depth == 12) {
        return AVIF_CLAMP((quantizer * (255 + 96) + 31) / 63 - 96, -96, 255);
    }
    assert(depth == 8);
    return AVIF_CLAMP((quantizer * 255 + 31) / 63, 0, 255);
}

// Converts quality to avm's quantizer in the range of [M:255], where M=0/-48/-96 for 8/10/12 bit.
// See --min-qp help in