diff options
Diffstat (limited to 'video/csputils.c')
| -rw-r--r-- | video/csputils.c | 28 |
1 files changed, 24 insertions, 4 deletions
diff --git a/video/csputils.c b/video/csputils.c index 60cdc54746..1f0fa7d90e 100644 --- a/video/csputils.c +++ b/video/csputils.c @@ -552,6 +552,27 @@ void mp_get_xyz2rgb_coeffs(struct mp_csp_params *params, m->c[i] = brightness; } +// Get multiplication factor required if image data is fit within the LSBs of a +// higher smaller bit depth isfixed-point texture data. +double mp_get_csp_mul(enum mp_csp csp, int input_bits, int texture_bits) +{ + assert(texture_bits >= input_bits); + + // Convenience for some irrelevant cases, e.g. rgb565 or disabling expansion. + if (!input_bits) + return 1; + + // RGB always uses the full range available. + if (csp == MP_CSP_RGB) + return ((1LL << input_bits) - 1.) / ((1LL << texture_bits) - 1.); + + if (csp == MP_CSP_XYZ) + return 1; + + // High bit depth YUV uses a range shifted from 8 bit. + return (1LL << input_bits) / ((1LL << texture_bits) - 1.) * 255 / 256; +} + /* Fill in the Y, U, V vectors of a yuv2rgb conversion matrix * based on the given luma weights of the R, G and B components (lr, lg, lb). * lr+lg+lb is assumed to equal 1. @@ -642,10 +663,9 @@ void mp_get_yuv2rgb_coeffs(struct mp_csp_params *params, struct mp_cmat *m) m->m[i][2] = huesin * u + huecos * v; } - assert(params->input_bits >= 8); - assert(params->texture_bits >= params->input_bits); - double s = (1 << (params->input_bits-8)) / ((1<<params->texture_bits)-1.); - // The values below are written in 0-255 scale + // The values below are written in 0-255 scale - thus bring s into range. + double s = + mp_get_csp_mul(colorspace, params->input_bits, params->texture_bits) / 255; struct yuvlevels { double ymin, ymax, cmin, cmid; } yuvlim = { 16*s, 235*s, 16*s, 128*s }, yuvfull = { 0*s, 255*s, 1*s, 128*s }, // '1' for symmetry around 128 |