diff options
author | Ronald S. Bultje <rsbultje@gmail.com> | 2016-05-03 13:53:17 -0400 |
---|---|---|
committer | Ronald S. Bultje <rsbultje@gmail.com> | 2016-05-10 08:37:55 -0400 |
commit | 431117dcb55c9bd47febf9ee3379e14a5d6595c8 (patch) | |
tree | e4bb5bed1f77a604e4368fbe77267e4fbfb5b91b /libavfilter/colorspacedsp_template.c | |
parent | 9486de5a85f0c54f241849d6b22bee943da557d0 (diff) |
vf_colorspace: add floyd-steinberg dithering option to full conversion.
Diffstat (limited to 'libavfilter/colorspacedsp_template.c')
-rw-r--r-- | libavfilter/colorspacedsp_template.c | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/libavfilter/colorspacedsp_template.c b/libavfilter/colorspacedsp_template.c index f225391301..db4a8d2361 100644 --- a/libavfilter/colorspacedsp_template.c +++ b/libavfilter/colorspacedsp_template.c @@ -199,6 +199,134 @@ static void fn(rgb2yuv)(uint8_t *_yuv[3], ptrdiff_t yuv_stride[3], } } +/* floyd-steinberg dithering - for any mid-top pixel A in a 3x2 block of pixels: + * 1 A 2 + * 3 4 5 + * the rounding error is distributed over the neighbouring pixels: + * 2: 7/16th, 3: 3/16th, 4: 5/16th and 5: 1/16th + */ +static void fn(rgb2yuv_fsb)(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], + int *rnd_scratch[3][2]) +{ + 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); + unsigned mask = (1 << sh) - 1; + + for (x = 0; x < w; x++) { + rnd_scratch[0][0][x] = + rnd_scratch[0][1][x] = rnd; + } + 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 (x = 0; x < w; x++) { + rnd_scratch[1][0][x] = + rnd_scratch[1][1][x] = + rnd_scratch[2][0][x] = + rnd_scratch[2][1][x] = rnd; + } + 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]; + int y00; +#if SS_W == 1 + int r01 = rgb0[x * 2 + 1], g01 = rgb1[x * 2 + 1], b01 = rgb2[x * 2 + 1]; + int y01; +#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]; + int y10, y11; +#endif +#endif + int u, v, diff; + + y00 = r00 * cry + g00 * cgy + b00 * cby + rnd_scratch[0][y & !SS_H][x << SS_W]; + diff = (y00 & mask) - rnd; + yuv0[x << SS_W] = av_clip_pixel(yuv_offset[0] + (y00 >> sh)); + rnd_scratch[0][ (y & !SS_H)][(x << SS_W) + 1] += (diff * 7 + 8) >> 4; + rnd_scratch[0][!(y & !SS_H)][(x << SS_W) - 1] += (diff * 3 + 8) >> 4; + rnd_scratch[0][!(y & !SS_H)][(x << SS_W) + 0] += (diff * 5 + 8) >> 4; + rnd_scratch[0][!(y & !SS_H)][(x << SS_W) + 1] += (diff * 1 + 8) >> 4; + rnd_scratch[0][ (y & !SS_H)][(x << SS_W) + 0] = rnd; +#if SS_W == 1 + y01 = r01 * cry + g01 * cgy + b01 * cby + rnd_scratch[0][y & !SS_H][x * 2 + 1]; + diff = (y01 & mask) - rnd; + yuv0[x * 2 + 1] = av_clip_pixel(yuv_offset[0] + (y01 >> sh)); + rnd_scratch[0][ (y & !SS_H)][x * 2 + 2] += (diff * 7 + 8) >> 4; + rnd_scratch[0][!(y & !SS_H)][x * 2 + 0] += (diff * 3 + 8) >> 4; + rnd_scratch[0][!(y & !SS_H)][x * 2 + 1] += (diff * 5 + 8) >> 4; + rnd_scratch[0][!(y & !SS_H)][x * 2 + 2] += (diff * 1 + 8) >> 4; + rnd_scratch[0][ (y & !SS_H)][x * 2 + 1] = rnd; +#if SS_H == 1 + y10 = r10 * cry + g10 * cgy + b10 * cby + rnd_scratch[0][1][x * 2 + 0]; + diff = (y10 & mask) - rnd; + yuv0[x * 2 + 0 + s0] = av_clip_pixel(yuv_offset[0] + (y10 >> sh)); + rnd_scratch[0][1][x * 2 + 1] += (diff * 7 + 8) >> 4; + rnd_scratch[0][0][x * 2 - 1] += (diff * 3 + 8) >> 4; + rnd_scratch[0][0][x * 2 + 0] += (diff * 5 + 8) >> 4; + rnd_scratch[0][0][x * 2 + 1] += (diff * 1 + 8) >> 4; + rnd_scratch[0][1][x * 2 + 0] = rnd; + + y11 = r11 * cry + g11 * cgy + b11 * cby + rnd_scratch[0][1][x * 2 + 1]; + diff = (y11 & mask) - rnd; + yuv0[x * 2 + 1 + s0] = av_clip_pixel(yuv_offset[0] + (y11 >> sh)); + rnd_scratch[0][1][x * 2 + 2] += (diff * 7 + 8) >> 4; + rnd_scratch[0][0][x * 2 + 0] += (diff * 3 + 8) >> 4; + rnd_scratch[0][0][x * 2 + 1] += (diff * 5 + 8) >> 4; + rnd_scratch[0][0][x * 2 + 2] += (diff * 1 + 8) >> 4; + rnd_scratch[0][1][x * 2 + 1] = rnd; +#endif +#endif + + u = avg(r00, r01, r10, r11) * cru + + avg(g00, g01, g10, g11) * cgu + + avg(b00, b01, b10, b11) * cburv + rnd_scratch[1][y & 1][x]; + diff = (u & mask) - rnd; + yuv1[x] = av_clip_pixel(uv_offset + (u >> sh)); + rnd_scratch[1][ (y & 1)][x + 1] += (diff * 7 + 8) >> 4; + rnd_scratch[1][!(y & 1)][x - 1] += (diff * 3 + 8) >> 4; + rnd_scratch[1][!(y & 1)][x + 0] += (diff * 5 + 8) >> 4; + rnd_scratch[1][!(y & 1)][x + 1] += (diff * 1 + 8) >> 4; + rnd_scratch[1][ (y & 1)][x + 0] = rnd; + + v = avg(r00, r01, r10, r11) * cburv + + avg(g00, g01, g10, g11) * cgv + + avg(b00, b01, b10, b11) * cbv + rnd_scratch[2][y & 1][x]; + diff = (v & mask) - rnd; + yuv2[x] = av_clip_pixel(uv_offset + (v >> sh)); + rnd_scratch[2][ (y & 1)][x + 1] += (diff * 7 + 8) >> 4; + rnd_scratch[2][!(y & 1)][x - 1] += (diff * 3 + 8) >> 4; + rnd_scratch[2][!(y & 1)][x + 0] += (diff * 5 + 8) >> 4; + rnd_scratch[2][!(y & 1)][x + 1] += (diff * 1 + 8) >> 4; + rnd_scratch[2][ (y & 1)][x + 0] = rnd; + } + + 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 |