/* Colour conversion routines (RGB <-> YUV) in plain C (C) 2000 Nemosoft Unv. nemosoft@smcc.demon.nl (C) 2005 Chris Monico ccvt_420p_bgr32() 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include "ccvt.h" #include #define PUSH_RGB24 1 #define PUSH_BGR24 2 #define PUSH_RGB32 3 #define PUSH_BGR32 4 /* This is a really simplistic approach. Speedups are welcomed. */ static void ccvt_420i(int width, int height, unsigned char *src, unsigned char *dst, int push) { int line, col, linewidth; int y, u, v, yy, vr, ug, vg, ub; int r, g, b; unsigned char *py, *pu, *pv; linewidth = width + (width >> 1); py = src; pu = py + 4; pv = pu + linewidth; y = *py++; yy = y << 8; u = *pu - 128; ug = 88 * u; ub = 454 * u; v = *pv - 128; vg = 183 * v; vr = 359 * v; /* The biggest problem is the interlaced data, and the fact that odd add even lines have V and U data, resp. */ for (line = 0; line < height; line++) { for (col = 0; col < width; col++) { r = (yy + vr) >> 8; g = (yy - ug - vg) >> 8; b = (yy + ub ) >> 8; switch(push) { case PUSH_RGB24: *dst++ = r; *dst++ = g; *dst++ = b; break; case PUSH_BGR24: *dst++ = b; *dst++ = g; *dst++ = r; break; case PUSH_RGB32: *dst++ = r; *dst++ = g; *dst++ = b; *dst++ = 0; break; case PUSH_BGR32: *dst++ = b; *dst++ = g; *dst++ = r; *dst++ = 0; break; } y = *py++; yy = y << 8; if ((col & 3) == 3) py += 2; // skip u/v if (col & 1) { if ((col & 3) == 3) { pu += 4; // skip y pv += 4; } else { pu++; pv++; } u = *pu - 128; ug = 88 * u; ub = 454 * u; v = *pv - 128; vg = 183 * v; vr = 359 * v; } } /* ..for col */ if (line & 1) { // odd line: go to next band pu += linewidth; pv += linewidth; } else { // rewind u/v pointers pu -= linewidth; pv -= linewidth; } } /* ..for line */ } void ccvt_420i_rgb24(int width, int height, const void *src, void *dst) { ccvt_420i(width, height, (unsigned char *)src, (unsigned char *)dst, PUSH_RGB24); } void ccvt_420i_bgr24(int width, int height, const void *src, void *dst) { ccvt_420i(width, height, (unsigned char *)src, (unsigned char *)dst, PUSH_BGR24); } void ccvt_420i_rgb32(int width, int height, const void *src, void *dst) { ccvt_420i(width, height, (unsigned char *)src, (unsigned char *)dst, PUSH_RGB32); } void ccvt_420i_bgr32(int width, int height, const void *src, void *dst) { ccvt_420i(width, height, (unsigned char *)src, (unsigned char *)dst, PUSH_BGR32); } void ccvt_420i_420p(int width, int height, const void *src, void *dsty, void *dstu, void *dstv) { short *s, *dy, *du, *dv; int line, col; s = (short *)src; dy = (short *)dsty; du = (short *)dstu; dv = (short *)dstv; for (line = 0; line < height; line++) { for (col = 0; col < width; col += 4) { *dy++ = *s++; *dy++ = *s++; if (line & 1) *dv++ = *s++; else *du++ = *s++; } /* ..for col */ } /* ..for line */ } void ccvt_420i_yuyv(int width, int height, const void *src, void *dst) { int line, col, linewidth; unsigned const char *py, *pu, *pv; unsigned char *d; linewidth = width + (width >> 1); py = (unsigned const char *)src; pu = (unsigned const char *)src + 4; pv = pu + linewidth; d = (unsigned char *)dst; for (line = 0; line < height; line++) { for (col = 0; col < width; col += 4) { /* four pixels in one go */ *d++ = *py++; *d++ = *pu++; *d++ = *py++; *d++ = *pv++; *d++ = *py++; *d++ = *pu++; *d++ = *py++; *d++ = *pv++; py += 2; pu += 4; pv += 4; } /* ..for col */ if (line & 1) { // odd line: go to next band pu += linewidth; pv += linewidth; } else { // rewind u/v pointers pu -= linewidth; pv -= linewidth; } } /* ..for line */ } /* CJM, 11/5/05: In my environment, these don't seem to be used so I didn't code them. But something needs to be linked in, so here we go: */ void ccvt_420p_rgb32(int width, int height, const void *srcy, const void *srcu, const void *srcv, void *dst) { assert(0); } void ccvt_rgb24_420p(int width, int height, const void *src, void *dsty, void *dstu, void *dstv) { assert(0); } void ccvt_bgr24_420p(int width, int height, const void *src, void *dsty, void *dstu, void *dstv) { assert(0); } #define MAX(_a, _b) ((_a)>(_b) ? (_a) : (_b)) #define MIN(_a, _b) ((_a)<(_b) ? (_a) : (_b)) /* CJM, 11/5/05 : it's not very fast, but it works. Doing two columns per pass doesn't help either, so I just kept it simple. */ void ccvt_420p_bgr32(int width, int height, const void *srcy, const void *srcu, const void *srcv, void *dst) { unsigned char *py, *pu, *pv, *lastY, *d; int y, u, v, yy, vr, ug, vg, ub; int r, g, b, row, col, w2; py=(unsigned char *)srcy; pu=(unsigned char *)srcu; pv=(unsigned char *)srcv; d=dst; lastY = &py[width*height-1]; row = col=0; w2 = width/2; u = *pu - 128; ug = 88*u; ub = 454*u; v = *pv - 128; vg = 183*v; vr = 359 * v; col=1; /* Makes the col%2 test easier if we count from 1 instead of 0. */ while (py>8; g = (yy - ug - vg) >> 8; b = (yy + ub) >> 8; /* This clamping is expensive, and should be done in a better way. */ r = MAX(MIN(255, r), 0); g = MAX(MIN(255, g), 0); b = MAX(MIN(255, b), 0); *d++ = (char)b; *d++ = (char)g; *d++ = (char)r; *d++ = 0; /* filler byte for alpha */ col++; py++; if (col&1) { pu++; pv++; u = *pu - 128; v = *pv - 128; ug = 88*u; ub = 454*u; vg = 183*v; vr = 359 * v; } if (col ==width) { col=1; row++; if ((row&1)==0) { pu -= w2; pv -= w2; } else { pu++; pv++; } u = *pu - 128; ug = 88*u; ub = 454*u; v = *pv - 128; vg = 183*v; vr = 359 * v; } } }