csputils: replace float[3][4] with a struct

Not being able to use the 3x3 part of the matrix was annoying, so split
it into a float[3][3] matrix and a separate float[3] constant vector.

1 files changed, 25 insertions, 12 deletions

diff --git a/video/csputils.h b/video/csputils.h
index 51de50c4b6..8e8d18e7df 100644
--- a/video/csputils.h
+++ b/video/csputils.h
@@ -214,28 +214,41 @@ int mp_chroma_location_to_av(enum mp_chroma_location mploc);
 void mp_get_chroma_location(enum mp_chroma_location loc, int *x, int *y);
 
 void mp_gen_gamma_map(unsigned char *map, int size, float gamma);
-#define ROW_R 0
-#define ROW_G 1
-#define ROW_B 2
-#define COL_Y 0
-#define COL_U 1
-#define COL_V 2
-#define COL_C 3
+
 struct mp_csp_primaries mp_get_csp_primaries(enum mp_csp_prim csp);
 
-void mp_apply_chromatic_adaptation(struct mp_csp_col_xy src, struct mp_csp_col_xy dest, float m[3][3]);
+/* Color conversion matrix: RGB = m * YUV + c
+ * m is in row-major matrix, with m[row][col], e.g.:
+ *     [ a11 a12 a13 ]     float m[3][3] = { { a11, a12, a13 },
+ *     [ a21 a22 a23 ]                       { a21, a22, a23 },
+ *     [ a31 a32 a33 ]                       { a31, a32, a33 } };
+ * This is accessed as e.g.: m[2-1][1-1] = a21
+ * In particular, each row contains all the coefficients for one of R, G, B,
+ * while each column contains all the coefficients for one of Y, U, V:
+ *     m[r,g,b][y,u,v] = ...
+ * The matrix could also be viewed as group of 3 vectors, e.g. the 1st column
+ * is the Y vector (1, 1, 1), the 2nd is the U vector, the 3rd the V vector.
+ * The matrix might also be used for other conversions and colorspaces.
+ */
+struct mp_cmat {
+    float m[3][3];
+    float c[3];
+};
+
+void mp_apply_chromatic_adaptation(struct mp_csp_col_xy src,
+                                   struct mp_csp_col_xy dest, float m[3][3]);
 void mp_get_cms_matrix(struct mp_csp_primaries src, struct mp_csp_primaries dest,
                        enum mp_render_intent intent, float cms_matrix[3][3]);
 void mp_get_rgb2xyz_matrix(struct mp_csp_primaries space, float m[3][3]);
 
 void mp_get_xyz2rgb_coeffs(struct mp_csp_params *params, struct mp_csp_primaries prim,
-                           enum mp_render_intent intent, float xyz2rgb[3][4]);
-void mp_get_yuv2rgb_coeffs(struct mp_csp_params *params, float yuv2rgb[3][4]);
+                           enum mp_render_intent intent, struct mp_cmat *xyz2rgb);
+void mp_get_yuv2rgb_coeffs(struct mp_csp_params *params, struct mp_cmat *yuv2rgb);
 void mp_gen_yuv2rgb_map(struct mp_csp_params *params, uint8_t *map, int size);
 
 void mp_mul_matrix3x3(float a[3][3], float b[3][3]);
 void mp_invert_matrix3x3(float m[3][3]);
-void mp_invert_yuv2rgb(float out[3][4], float in[3][4]);
-void mp_map_int_color(float matrix[3][4], int clip_bits, int c[3]);
+void mp_invert_yuv2rgb(struct mp_cmat *out, struct mp_cmat *in);
+void mp_map_int_color(struct mp_cmat *matrix, int clip_bits, int c[3]);
 
 #endif /* MPLAYER_CSPUTILS_H */