vo_gpu: improve XYZ conversion

Fixes #4925

2 files changed, 14 insertions, 6 deletions

diff --git a/video/csputils.c b/video/csputils.c
index a0db6c8cd4..aaa32614b7 100644
--- a/video/csputils.c
+++ b/video/csputils.c
@@ -619,21 +619,22 @@ void mp_get_cms_matrix(struct mp_csp_primaries src, struct mp_csp_primaries dest
     mp_mul_matrix3x3(m, tmp);
 }
 
-// get the coefficients of an SMPTE 428-1 xyz -> rgb conversion matrix
+// get the coefficients of an ST 428-1 xyz -> rgb conversion matrix
 // intent = the rendering intent used to convert to the target primaries
 static void mp_get_xyz2rgb_coeffs(struct mp_csp_params *params,
                                   enum mp_render_intent intent, struct mp_cmat *m)
 {
-    struct mp_csp_primaries prim = mp_get_csp_primaries(params->color.primaries);
+    // Convert to DCI-P3
+    struct mp_csp_primaries prim = mp_get_csp_primaries(MP_CSP_PRIM_DCI_P3);
     float brightness = params->brightness;
     mp_get_rgb2xyz_matrix(prim, m->m);
     mp_invert_matrix3x3(m->m);
 
     // All non-absolute mappings want to map source white to target white
     if (intent != MP_INTENT_ABSOLUTE_COLORIMETRIC) {
-        // SMPTE 428-1 defines the calibration white point as CIE xy (0.314, 0.351)
-        static const struct mp_csp_col_xy smpte428 = {0.314, 0.351};
-        mp_apply_chromatic_adaptation(smpte428, prim.white, m->m);
+        // SMPTE EG 432-1 Annex H defines the white point as equal energy
+        static const struct mp_csp_col_xy smpte432 = {1.0/3.0, 1.0/3.0};
+        mp_apply_chromatic_adaptation(smpte432, prim.white, m->m);
     }
 
     // Since this outputs linear RGB rather than companded RGB, we
diff --git a/video/out/gpu/video.c b/video/out/gpu/video.c
index 3f789b6046..df689b53c3 100644
--- a/video/out/gpu/video.c
+++ b/video/out/gpu/video.c
@@ -2333,7 +2333,7 @@ static void pass_convert_yuv(struct gl_video *p)
 
     // Pre-colormatrix input gamma correction
     if (cparams.color.space == MP_CSP_XYZ)
-        GLSL(color.rgb = pow(color.rgb, vec3(2.6));) // linear light
+        pass_linearize(p->sc, p->image_params.color.gamma);
 
     // We always explicitly normalize the range in pass_read_video
     cparams.input_bits = cparams.texture_bits = 0;
@@ -2347,6 +2347,13 @@ static void pass_convert_yuv(struct gl_video *p)
 
     GLSL(color.rgb = mat3(colormatrix) * color.rgb + colormatrix_c;)
 
+    if (cparams.color.space == MP_CSP_XYZ) {
+        pass_delinearize(p->sc, p->image_params.color.gamma);
+        // mp_get_csp_matrix implicitly converts XYZ to DCI-P3
+        p->image_params.color.space = MP_CSP_RGB;
+        p->image_params.color.primaries = MP_CSP_PRIM_DCI_P3;
+    }
+
     if (p->image_params.color.space == MP_CSP_BT_2020_C) {
         // Conversion for C'rcY'cC'bc via the BT.2020 CL system:
         // C'bc = (B'-Y'c) / 1.9404  | C'bc <= 0