vf_colorspace: use enums for bpp/subsampling array indices.

Also add some documentation for each function to colorspacedsp.h.

1 files changed, 27 insertions, 4 deletions

diff --git a/libavfilter/colorspacedsp.h b/libavfilter/colorspacedsp.h
index 7a64f9dfa5..a81e4f0a52 100644
--- a/libavfilter/colorspacedsp.h
+++ b/libavfilter/colorspacedsp.h
@@ -42,12 +42,35 @@ typedef void (*yuv2yuv_fn)(uint8_t *yuv_out[3], const ptrdiff_t yuv_out_stride[3
                            int w, int h, const int16_t yuv2yuv_coeffs[3][3][8],
                            const int16_t yuv_offset[2][8]);
 
+enum BitDepthIndex {
+    BPP_8,
+    BPP_10,
+    BPP_12,
+    NB_BPP,
+};
+
+enum ChromaSubsamplingIndex {
+    SS_444,
+    SS_422,
+    SS_420,
+    NB_SS,
+};
+
 typedef struct ColorSpaceDSPContext {
-    yuv2rgb_fn yuv2rgb[3 /* 0: 8bit, 1: 10bit, 2: 12bit */][3 /* 0: 444, 1: 422, 2: 420 */];
-    rgb2yuv_fn rgb2yuv[3 /* 0: 8bit, 1: 10bit, 2: 12bit */][3 /* 0: 444, 1: 422, 2: 420 */];
-    rgb2yuv_fsb_fn rgb2yuv_fsb[3 /* 0: 8bit, 1: 10bit, 2: 12bit */][3 /* 0: 444, 1: 422, 2: 420 */];
-    yuv2yuv_fn yuv2yuv[3 /* in_depth */][3 /* out_depth */][3 /* 0: 444, 1: 422, 2: 420 */];
+    /* Convert input YUV pixel buffer from a user into an internal, 15bpp array
+     * of intermediate RGB data. */
+    yuv2rgb_fn yuv2rgb[NB_BPP][NB_SS];
+    /* Convert intermediate RGB data (15bpp, internal format) into YUV data and
+     * store into user-provided output buffer */
+    rgb2yuv_fn rgb2yuv[NB_BPP][NB_SS];
+    /* Same as rgb2yuv(), but use floyd-steinberg dithering */
+    rgb2yuv_fsb_fn rgb2yuv_fsb[NB_BPP][NB_SS];
+    /* Direct yuv-to-yuv conversion (input and output are both user-provided
+     * buffers) */
+    yuv2yuv_fn yuv2yuv[NB_BPP /* in */][NB_BPP /* out */][NB_SS];
 
+    /* In-place 3x3 matrix multiplication. Input and output are both 15bpp
+     * (our internal data format) */
     void (*multiply3x3)(int16_t *data[3], ptrdiff_t stride,
                         int w, int h, const int16_t m[3][3][8]);
 } ColorSpaceDSPContext;