lavfi: new colorspace conversion filter.

The intent here is similar to colormatrix, but it's LGPLv2.1-or-later
(instead of GPLv2.0) and supports gamma/chromaticity correction.

1 files changed, 214 insertions, 0 deletions

diff --git a/libavfilter/colorspacedsp_template.c b/libavfilter/colorspacedsp_template.c
new file mode 100644
index 0000000..a32a029
--- /dev/null
+++ b/libavfilter/colorspacedsp_template.c
@@ -0,0 +1,214 @@
+/*
+ * Copyright (c) 2016 Ronald S. Bultje <rsbultje@gmail.com>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "libavutil/avassert.h"
+
+#undef avg
+#undef ss
+
+#if SS_W == 0
+#define ss 444
+#define avg(a,b,c,d) (a)
+#elif SS_H == 0
+#define ss 422
+#define avg(a,b,c,d) ((a + b + 1) >> 1)
+#else
+#define ss 420
+#define avg(a,b,c,d) ((a + b + c + d + 2) >> 2)
+#endif
+
+#undef fn
+#undef fn2
+#undef fn3
+#define fn3(a,b,c) a##_##c##p##b##_c
+#define fn2(a,b,c) fn3(a,b,c)
+#define fn(a) fn2(a, BIT_DEPTH, ss)
+
+#undef pixel
+#undef av_clip_pixel
+#if BIT_DEPTH == 8
+#define pixel uint8_t
+#define av_clip_pixel(x) av_clip_uint8(x)
+#else
+#define pixel uint16_t
+#define av_clip_pixel(x) av_clip_uintp2(x, BIT_DEPTH)
+#endif
+
+static void fn(yuv2rgb)(int16_t *rgb[3], ptrdiff_t rgb_stride,
+                        uint8_t *_yuv[3], ptrdiff_t yuv_stride[3],
+                        int w, int h, const int16_t yuv2rgb_coeffs[3][3][8],
+                        const int16_t yuv_offset[8])
+{
+    pixel **yuv = (pixel **) _yuv;
+    const pixel *yuv0 = yuv[0], *yuv1 = yuv[1], *yuv2 = yuv[2];
+    int16_t *rgb0 = rgb[0], *rgb1 = rgb[1], *rgb2 = rgb[2];
+    int y, x;
+    int cy = yuv2rgb_coeffs[0][0][0];
+    int crv = yuv2rgb_coeffs[0][2][0];
+    int cgu = yuv2rgb_coeffs[1][1][0];
+    int cgv = yuv2rgb_coeffs[1][2][0];
+    int cbu = yuv2rgb_coeffs[2][1][0];
+    const int sh = BIT_DEPTH - 1, rnd = 1 << (sh - 1);
+    const int uv_offset = 128 << (BIT_DEPTH - 8);
+
+    av_assert2(yuv2rgb_coeffs[0][1][0] == 0);
+    av_assert2(yuv2rgb_coeffs[2][2][0] == 0);
+    av_assert2(yuv2rgb_coeffs[1][0][0] == cy && yuv2rgb_coeffs[2][0][0] == cy);
+
+    w = AV_CEIL_RSHIFT(w, SS_W);
+    h = AV_CEIL_RSHIFT(h, SS_H);
+    for (y = 0; y < h; y++) {
+        for (x = 0; x < w; x++) {
+            int y00 = yuv0[x << SS_W] - yuv_offset[0];
+#if SS_W == 1
+            int y01 = yuv0[2 * x + 1] - yuv_offset[0];
+#if SS_H == 1
+            int y10 = yuv0[yuv_stride[0] / sizeof(pixel) + 2 * x] - yuv_offset[0];
+            int y11 = yuv0[yuv_stride[0] / sizeof(pixel) + 2 * x + 1] - yuv_offset[0];
+#endif
+#endif
+            int u = yuv1[x] - uv_offset, v = yuv2[x] - uv_offset;
+
+            rgb0[x << SS_W]              = av_clip_int16((y00 * cy + crv * v + rnd) >> sh);
+#if SS_W == 1
+            rgb0[2 * x + 1]              = av_clip_int16((y01 * cy + crv * v + rnd) >> sh);
+#if SS_H == 1
+            rgb0[2 * x + rgb_stride]     = av_clip_int16((y10 * cy + crv * v + rnd) >> sh);
+            rgb0[2 * x + rgb_stride + 1] = av_clip_int16((y11 * cy + crv * v + rnd) >> sh);
+#endif
+#endif
+
+            rgb1[x << SS_W]              = av_clip_int16((y00 * cy + cgu * u +
+                                                          cgv * v + rnd) >> sh);
+#if SS_W == 1
+            rgb1[2 * x + 1]              = av_clip_int16((y01 * cy + cgu * u +
+                                                          cgv * v + rnd) >> sh);
+#if SS_H == 1
+            rgb1[2 * x + rgb_stride]     = av_clip_int16((y10 * cy + cgu * u +
+                                                          cgv * v + rnd) >> sh);
+            rgb1[2 * x + rgb_stride + 1] = av_clip_int16((y11 * cy + cgu * u +
+                                                          cgv * v + rnd) >> sh);
+#endif
+#endif
+
+            rgb2[x << SS_W]              = av_clip_int16((y00 * cy + cbu * u + rnd) >> sh);
+#if SS_W == 1
+            rgb2[2 * x + 1]              = av_clip_int16((y01 * cy + cbu * u + rnd) >> sh);
+#if SS_H == 1
+            rgb2[2 * x + rgb_stride]     = av_clip_int16((y10 * cy + cbu * u + rnd) >> sh);
+            rgb2[2 * x + rgb_stride + 1] = av_clip_int16((y11 * cy + cbu * u + rnd) >> sh);
+#endif
+#endif
+        }
+
+        yuv0 += (yuv_stride[0] * (1 << SS_H)) / sizeof(pixel);
+        yuv1 += yuv_stride[1] / sizeof(pixel);
+        yuv2 += yuv_stride[2] / sizeof(pixel);
+        rgb0 += rgb_stride * (1 << SS_H);
+        rgb1 += rgb_stride * (1 << SS_H);
+        rgb2 += rgb_stride * (1 << SS_H);
+    }
+}
+
+static void fn(rgb2yuv)(uint8_t *_yuv[3], ptrdiff_t yuv_stride[3],
+                        int16_t *rgb[3], ptrdiff_t s,
+                        int w, int h, const int16_t rgb2yuv_coeffs[3][3][8],
+                        const int16_t yuv_offset[8])
+{
+    pixel **yuv = (pixel **) _yuv;
+    pixel *yuv0 = yuv[0], *yuv1 = yuv[1], *yuv2 = yuv[2];
+    const int16_t *rgb0 = rgb[0], *rgb1 = rgb[1], *rgb2 = rgb[2];
+    int y, x;
+    const int sh = 29 - BIT_DEPTH;
+    const int rnd = 1 << (sh - 1);
+    int cry = rgb2yuv_coeffs[0][0][0];
+    int cgy = rgb2yuv_coeffs[0][1][0];
+    int cby = rgb2yuv_coeffs[0][2][0];
+    int cru = rgb2yuv_coeffs[1][0][0];
+    int cgu = rgb2yuv_coeffs[1][1][0];
+    int cburv = rgb2yuv_coeffs[1][2][0];
+    int cgv = rgb2yuv_coeffs[2][1][0];
+    int cbv = rgb2yuv_coeffs[2][2][0];
+    ptrdiff_t s0 = yuv_stride[0] / sizeof(pixel);
+    const int uv_offset = 128 << (BIT_DEPTH - 8);
+
+    av_assert2(rgb2yuv_coeffs[1][2][0] == rgb2yuv_coeffs[2][0][0]);
+    w = AV_CEIL_RSHIFT(w, SS_W);
+    h = AV_CEIL_RSHIFT(h, SS_H);
+    for (y = 0; y < h; y++) {
+        for (x = 0; x < w; x++) {
+            int r00 = rgb0[x << SS_W], g00 = rgb1[x << SS_W], b00 = rgb2[x << SS_W];
+#if SS_W == 1
+            int r01 = rgb0[x * 2 + 1], g01 = rgb1[x * 2 + 1], b01 = rgb2[x * 2 + 1];
+#if SS_H == 1
+            int r10 = rgb0[x * 2 + 0 + s], g10 = rgb1[x * 2 + 0 + s], b10 = rgb2[x * 2 + 0 + s];
+            int r11 = rgb0[x * 2 + 1 + s], g11 = rgb1[x * 2 + 1 + s], b11 = rgb2[x * 2 + 1 + s];
+#endif
+#endif
+
+            yuv0[x << SS_W]      = av_clip_pixel(yuv_offset[0] +
+                                                 ((r00 * cry + g00 * cgy +
+                                                   b00 * cby + rnd) >> sh));
+#if SS_W == 1
+            yuv0[x * 2 + 1]      = av_clip_pixel(yuv_offset[0] +
+                                                 ((r01 * cry + g01 * cgy +
+                                                   b01 * cby + rnd) >> sh));
+#if SS_H == 1
+            yuv0[x * 2 + 0 + s0] = av_clip_pixel(yuv_offset[0] +
+                                                 ((r10 * cry + g10 * cgy +
+                                                   b10 * cby + rnd) >> sh));
+            yuv0[x * 2 + 1 + s0] = av_clip_pixel(yuv_offset[0] +
+                                                 ((r11 * cry + g11 * cgy +
+                                                   b11 * cby + rnd) >> sh));
+#endif
+#endif
+
+            yuv1[x]      = av_clip_pixel(uv_offset +
+                                         ((avg(r00, r01, r10, r11) * cru +
+                                           avg(g00, g01, g10, g11) * cgu +
+                                           avg(b00, b01, b10, b11) * cburv + rnd) >> sh));
+            yuv2[x]      = av_clip_pixel(uv_offset +
+                                         ((avg(r00, r01, r10, r11) * cburv +
+                                           avg(g00, g01, g10, g11) * cgv +
+                                           avg(b00, b01, b10, b11) * cbv + rnd) >> sh));
+        }
+
+        yuv0 += s0 * (1 << SS_H);
+        yuv1 += yuv_stride[1] / sizeof(pixel);
+        yuv2 += yuv_stride[2] / sizeof(pixel);
+        rgb0 += s * (1 << SS_H);
+        rgb1 += s * (1 << SS_H);
+        rgb2 += s * (1 << SS_H);
+    }
+}
+
+#undef IN_BIT_DEPTH
+#undef OUT_BIT_DEPTH
+#define OUT_BIT_DEPTH BIT_DEPTH
+#define IN_BIT_DEPTH 8
+#include "colorspacedsp_yuv2yuv_template.c"
+
+#undef IN_BIT_DEPTH
+#define IN_BIT_DEPTH 10
+#include "colorspacedsp_yuv2yuv_template.c"
+
+#undef IN_BIT_DEPTH
+#define IN_BIT_DEPTH 12
+#include "colorspacedsp_yuv2yuv_template.c"