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Diffstat (limited to 'libvo/csputils.c')
| -rw-r--r-- | libvo/csputils.c | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/libvo/csputils.c b/libvo/csputils.c new file mode 100644 index 0000000000..6f69ec4212 --- /dev/null +++ b/libvo/csputils.c @@ -0,0 +1,160 @@ +/* + * Common code related to colorspaces and conversion + * + * Copyleft (C) 2009 Reimar Döffinger <Reimar.Doeffinger@gmx.de> + * + * This file is part of MPlayer. + * + * MPlayer is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * MPlayer 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with MPlayer; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include <stdint.h> +#include <math.h> +#include "libavutil/common.h" +#include "csputils.h" + +/** + * \brief little helper function to create a lookup table for gamma + * \param map buffer to create map into + * \param size size of buffer + * \param gamma gamma value + */ +void mp_gen_gamma_map(uint8_t *map, int size, float gamma) { + int i; + if (gamma == 1.0) { + for (i = 0; i < size; i++) + map[i] = 255 * i / (size - 1); + return; + } + gamma = 1.0 / gamma; + for (i = 0; i < size; i++) { + float tmp = (float)i / (size - 1.0); + tmp = pow(tmp, gamma); + if (tmp > 1.0) tmp = 1.0; + if (tmp < 0.0) tmp = 0.0; + map[i] = 255 * tmp; + } +} + +/** + * \brief get the coefficients of the yuv -> rgb conversion matrix + * \param params struct specifying the properties of the conversion like brightness, ... + * \param yuv2rgb array to store coefficients into + * + * Note: contrast, hue and saturation will only work as expected with YUV formats, + * not with e.g. MP_CSP_XYZ + */ +void mp_get_yuv2rgb_coeffs(struct mp_csp_params *params, float yuv2rgb[3][4]) { + float uvcos = params->saturation * cos(params->hue); + float uvsin = params->saturation * sin(params->hue); + int format = params->format; + int i; + const float (*uv_coeffs)[3]; + const float *level_adjust; + static const float yuv_pc_level_adjust[4] = {-16 / 255.0, -128 / 255.0, -128 / 255.0, 1.164}; + static const float yuv_tv_level_adjust[4] = {0, -128 / 255.0, -128 / 255.0, 0}; + static const float xyz_level_adjust[4] = {0, 0, 0, 0}; + static const float uv_coeffs_table[MP_CSP_COUNT][3][3] = { + [MP_CSP_DEFAULT] = { + {1, 0.000, 1.596}, + {1, -0.391, -0.813}, + {1, 2.018, 0.000} + }, + [MP_CSP_BT_601] = { + {1, 0.000, 1.403}, + {1, -0.344, -0.714}, + {1, 1.773, 0.000} + }, + [MP_CSP_BT_709] = { + {1, 0.0000, 1.5701}, + {1, -0.1870, -0.4664}, + {1, 1.8556, 0.0000} + }, + [MP_CSP_SMPTE_240M] = { + {1, 0.0000, 1.5756}, + {1, -0.2253, -0.5000}, + {1, 1.8270, 0.0000} + }, + [MP_CSP_EBU] = { + {1, 0.000, 1.140}, + {1, -0.396, -0.581}, + {1, 2.029, 0.000} + }, + [MP_CSP_XYZ] = { + { 3.2404542, -1.5371385, -0.4985314}, + {-0.9692660, 1.8760108, 0.0415560}, + { 0.0556434, -0.2040259, 1.0572252} + }, + }; + + if (format < 0 || format >= MP_CSP_COUNT) + format = MP_CSP_DEFAULT; + uv_coeffs = uv_coeffs_table[format]; + level_adjust = yuv_pc_level_adjust; + if (format == MP_CSP_XYZ) + level_adjust = xyz_level_adjust; + + for (i = 0; i < 3; i++) { + yuv2rgb[i][COL_C] = params->brightness; + yuv2rgb[i][COL_Y] = uv_coeffs[i][COL_Y] * level_adjust[COL_C] * params->contrast; + yuv2rgb[i][COL_C] += level_adjust[COL_Y] * yuv2rgb[i][COL_Y]; + yuv2rgb[i][COL_U] = uv_coeffs[i][COL_U] * uvcos + uv_coeffs[i][COL_V] * uvsin; + yuv2rgb[i][COL_C] += level_adjust[COL_U] * yuv2rgb[i][COL_U]; + yuv2rgb[i][COL_V] = uv_coeffs[i][COL_U] * uvsin + uv_coeffs[i][COL_V] * uvcos; + yuv2rgb[i][COL_C] += level_adjust[COL_V] * yuv2rgb[i][COL_V]; + // this "centers" contrast control so that e.g. a contrast of 0 + // leads to a grey image, not a black one + yuv2rgb[i][COL_C] += 0.5 - params->contrast / 2.0; + } +} + +//! size of gamma map use to avoid slow exp function in gen_yuv2rgb_map +#define GMAP_SIZE (1024) +/** + * \brief generate a 3D YUV -> RGB map + * \param params struct containing parameters like brightness, gamma, ... + * \param map where to store map. Must provide space for (size + 2)^3 elements + * \param size size of the map, excluding border + */ +void mp_gen_yuv2rgb_map(struct mp_csp_params *params, unsigned char *map, int size) { + int i, j, k, l; + float step = 1.0 / size; + float y, u, v; + float yuv2rgb[3][4]; + unsigned char gmaps[3][GMAP_SIZE]; + mp_gen_gamma_map(gmaps[0], GMAP_SIZE, params->rgamma); + mp_gen_gamma_map(gmaps[1], GMAP_SIZE, params->ggamma); + mp_gen_gamma_map(gmaps[2], GMAP_SIZE, params->bgamma); + mp_get_yuv2rgb_coeffs(params, yuv2rgb); + for (i = 0; i < 3; i++) + for (j = 0; j < 4; j++) + yuv2rgb[i][j] *= GMAP_SIZE - 1; + v = 0; + for (i = -1; i <= size; i++) { + u = 0; + for (j = -1; j <= size; j++) { + y = 0; + for (k = -1; k <= size; k++) { + for (l = 0; l < 3; l++) { + float rgb = yuv2rgb[l][COL_Y] * y + yuv2rgb[l][COL_U] * u + yuv2rgb[l][COL_V] * v + yuv2rgb[l][COL_C]; + *map++ = gmaps[l][av_clip(rgb, 0, GMAP_SIZE - 1)]; + } + y += (k == -1 || k == size - 1) ? step / 2 : step; + } + u += (j == -1 || j == size - 1) ? step / 2 : step; + } + v += (i == -1 || i == size - 1) ? step / 2 : step; + } +} |