diff options
Diffstat (limited to 'libavcodec/imgconvert.c')
| -rw-r--r-- | libavcodec/imgconvert.c | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/libavcodec/imgconvert.c b/libavcodec/imgconvert.c new file mode 100644 index 0000000000..01289d4d83 --- /dev/null +++ b/libavcodec/imgconvert.c @@ -0,0 +1,214 @@ +/* + * Misc image convertion routines + * Copyright (c) 2001 Gerard Lantau. + * + * This program 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. + * + * This program 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 this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ +#include <stdlib.h> +#include <stdio.h> +#include <string.h> +#include "avcodec.h" + +/* XXX: totally non optimized */ + +static void yuv422_to_yuv420p(UINT8 *lum, UINT8 *cb, UINT8 *cr, + UINT8 *src, int width, int height) +{ + int x, y; + UINT8 *p = src; + + for(y=0;y<height;y+=2) { + for(x=0;x<width;x+=2) { + lum[0] = p[0]; + cb[0] = p[1]; + lum[1] = p[2]; + cr[0] = p[3]; + p += 4; + lum += 2; + cb++; + cr++; + } + for(x=0;x<width;x+=2) { + lum[0] = p[0]; + lum[1] = p[2]; + p += 4; + lum += 2; + } + } +} + +#define SCALEBITS 8 +#define ONE_HALF (1 << (SCALEBITS - 1)) +#define FIX(x) ((int) ((x) * (1L<<SCALEBITS) + 0.5)) + +static void rgb24_to_yuv420p(UINT8 *lum, UINT8 *cb, UINT8 *cr, + UINT8 *src, int width, int height) +{ + int wrap, wrap3, x, y; + int r, g, b, r1, g1, b1; + UINT8 *p; + + wrap = width; + wrap3 = width * 3; + p = src; + for(y=0;y<height;y+=2) { + for(x=0;x<width;x+=2) { + r = p[0]; + g = p[1]; + b = p[2]; + r1 = r; + g1 = g; + b1 = b; + lum[0] = (FIX(0.29900) * r + FIX(0.58700) * g + + FIX(0.11400) * b + ONE_HALF) >> SCALEBITS; + r = p[3]; + g = p[4]; + b = p[5]; + r1 += r; + g1 += g; + b1 += b; + lum[1] = (FIX(0.29900) * r + FIX(0.58700) * g + + FIX(0.11400) * b + ONE_HALF) >> SCALEBITS; + p += wrap3; + lum += wrap; + + r = p[0]; + g = p[1]; + b = p[2]; + r1 += r; + g1 += g; + b1 += b; + lum[0] = (FIX(0.29900) * r + FIX(0.58700) * g + + FIX(0.11400) * b + ONE_HALF) >> SCALEBITS; + r = p[3]; + g = p[4]; + b = p[5]; + r1 += r; + g1 += g; + b1 += b; + lum[1] = (FIX(0.29900) * r + FIX(0.58700) * g + + FIX(0.11400) * b + ONE_HALF) >> SCALEBITS; + + cb[0] = ((- FIX(0.16874) * r1 - FIX(0.33126) * g1 + + FIX(0.50000) * b1 + 4 * ONE_HALF - 1) >> (SCALEBITS + 2)) + 128; + cr[0] = ((FIX(0.50000) * r1 - FIX(0.41869) * g1 - + FIX(0.08131) * b1 + 4 * ONE_HALF - 1) >> (SCALEBITS + 2)) + 128; + + cb++; + cr++; + p += -wrap3 + 2 * 3; + lum += -wrap + 2; + } + p += wrap3; + lum += wrap; + } +} + +static void bgr24_to_yuv420p(UINT8 *lum, UINT8 *cb, UINT8 *cr, + UINT8 *src, int width, int height) +{ + int wrap, wrap3, x, y; + int r, g, b, r1, g1, b1; + UINT8 *p; + + wrap = width; + wrap3 = width * 3; + p = src; + for(y=0;y<height;y+=2) { + for(x=0;x<width;x+=2) { + b = p[0]; + g = p[1]; + r = p[2]; + r1 = r; + g1 = g; + b1 = b; + lum[0] = (FIX(0.29900) * r + FIX(0.58700) * g + + FIX(0.11400) * b + ONE_HALF) >> SCALEBITS; + b = p[3]; + g = p[4]; + r = p[5]; + r1 += r; + g1 += g; + b1 += b; + lum[1] = (FIX(0.29900) * r + FIX(0.58700) * g + + FIX(0.11400) * b + ONE_HALF) >> SCALEBITS; + p += wrap3; + lum += wrap; + + b = p[0]; + g = p[1]; + r = p[2]; + r1 += r; + g1 += g; + b1 += b; + lum[0] = (FIX(0.29900) * r + FIX(0.58700) * g + + FIX(0.11400) * b + ONE_HALF) >> SCALEBITS; + b = p[3]; + g = p[4]; + r = p[5]; + r1 += r; + g1 += g; + b1 += b; + lum[1] = (FIX(0.29900) * r + FIX(0.58700) * g + + FIX(0.11400) * b + ONE_HALF) >> SCALEBITS; + + cb[0] = ((- FIX(0.16874) * r1 - FIX(0.33126) * g1 + + FIX(0.50000) * b1 + 4 * ONE_HALF - 1) >> (SCALEBITS + 2)) + 128; + cr[0] = ((FIX(0.50000) * r1 - FIX(0.41869) * g1 - + FIX(0.08131) * b1 + 4 * ONE_HALF - 1) >> (SCALEBITS + 2)) + 128; + + cb++; + cr++; + p += -wrap3 + 2 * 3; + lum += -wrap + 2; + } + p += wrap3; + lum += wrap; + } +} + +int img_convert_to_yuv420(UINT8 *img_out, UINT8 *img, + int pix_fmt, int width, int height) +{ + UINT8 *pict; + int size, size_out; + UINT8 *picture[3]; + + pict = img_out; + size = width * height; + size_out = (size * 3) / 2; + picture[0] = pict; + picture[1] = pict + size; + picture[2] = picture[1] + (size / 4); + + switch(pix_fmt) { + case PIX_FMT_YUV420P: + memcpy(pict, img, size_out); + break; + case PIX_FMT_YUV422: + yuv422_to_yuv420p(picture[0], picture[1], picture[2], + img, width, height); + break; + case PIX_FMT_RGB24: + rgb24_to_yuv420p(picture[0], picture[1], picture[2], + img, width, height); + break; + case PIX_FMT_BGR24: + bgr24_to_yuv420p(picture[0], picture[1], picture[2], + img, width, height); + break; + } + return size_out; +} |