/* * idct.c * Copyright (C) 2000-2003 Michel Lespinasse * Copyright (C) 1999-2000 Aaron Holtzman * * This file is part of mpeg2dec, a free MPEG-2 video stream decoder. * See http://libmpeg2.sourceforge.net/ for updates. * * mpeg2dec 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. * * mpeg2dec 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 * * libmpeg2 sync history: * 2008-07-01 - CVS revision 1.36 */ #include "plugin.h" #include "mpeg2dec_config.h" #include "mpeg2.h" #include "attributes.h" #include "mpeg2_internal.h" #if defined(CPU_COLDFIRE) || defined (CPU_ARM_CLASSIC) #define IDCT_ASM #endif #ifndef IDCT_ASM #define W1 2841 /* 2048 * sqrt (2) * cos (1 * pi / 16) */ #define W2 2676 /* 2048 * sqrt (2) * cos (2 * pi / 16) */ #define W3 2408 /* 2048 * sqrt (2) * cos (3 * pi / 16) */ #define W5 1609 /* 2048 * sqrt (2) * cos (5 * pi / 16) */ #define W6 1108 /* 2048 * sqrt (2) * cos (6 * pi / 16) */ #define W7 565 /* 2048 * sqrt (2) * cos (7 * pi / 16) */ /* * In legal streams, the IDCT output should be between -384 and +384. * In corrupted streams, it is possible to force the IDCT output to go * to +-3826 - this is the worst case for a column IDCT where the * column inputs are 16-bit values. */ #define CLIP(i) \ ({ typeof (i) _i = (i); \ if ((_i & 0xff) != _i) \ _i = ~(_i >> (8*sizeof(_i) - 1)); \ _i; }) #if 0 #define BUTTERFLY(t0,t1,W0,W1,d0,d1) \ do { \ t0 = W0 * d0 + W1 * d1; \ t1 = W0 * d1 - W1 * d0; \ } while (0) #else #define BUTTERFLY(t0,t1,W0,W1,d0,d1) \ do { \ int tmp = W0 * (d0 + d1); \ t0 = tmp + (W1 - W0) * d1; \ t1 = tmp - (W1 + W0) * d0; \ } while (0) #endif static inline void idct_row (int16_t * const block) { int d0, d1, d2, d3; int a0, a1, a2, a3, b0, b1, b2, b3; int t0, t1, t2, t3; /* shortcut */ if (likely (!(block[1] | ((int32_t *)block)[1] | ((int32_t *)block)[2] | ((int32_t *)block)[3]))) { uint32_t tmp = (uint16_t) (block[0] >> 1); tmp |= tmp << 16; ((int32_t *)block)[0] = tmp; ((int32_t *)block)[1] = tmp; ((int32_t *)block)[2] = tmp; ((int32_t *)block)[3] = tmp; return; } d0 = (block[0] << 11) + 2048; d1 = block[1]; d2 = block[2] << 11; d3 = block[3]; t0 = d0 + d2; t1 = d0 - d2; BUTTERFLY (t2, t3, W6, W2, d3, d1); a0 = t0 + t2; a1 = t1 + t3; a2 = t1 - t3; a3 = t0 - t2; d0 = block[4]; d1 = block[5]; d2 = block[6]; d3 = block[7]; BUTTERFLY (t0, t1, W7, W1, d3, d0); BUTTERFLY (t2, t3, W3, W5, d1, d2); b0 = t0 + t2; b3 = t1 + t3; t0 -= t2; t1 -= t3; b1 = ((t0 + t1) >> 8) * 181; b2 = ((t0 - t1) >> 8) * 181; block[0] = (a0 + b0) >> 12; block[1] = (a1 + b1) >> 12; block[2] = (a2 + b2) >> 12; block[3] = (a3 + b3) >> 12; block[4] = (a3 - b3) >> 12; block[5] = (a2 - b2) >> 12; block[6] = (a1 - b1) >> 12; block[7] = (a0 - b0) >> 12; } static inline void idct_col (int16_t * const block) { int d0, d1, d2, d3; int a0, a1, a2, a3, b0, b1, b2, b3; int t0, t1, t2, t3; d0 = (block[8*0] << 11) + 65536; d1 = block[8*1]; d2 = block[8*2] << 11; d3 = block[8*3]; t0 = d0 + d2; t1 = d0 - d2; BUTTERFLY (t2, t3, W6, W2, d3, d1); a0 = t0 + t2; a1 = t1 + t3; a2 = t1 - t3; a3 = t0 - t2; d0 = block[8*4]; d1 = block[8*5]; d2 = block[8*6]; d3 = block[8*7]; BUTTERFLY (t0, t1, W7, W1, d3, d0); BUTTERFLY (t2, t3, W3, W5, d1, d2); b0 = t0 + t2; b3 = t1 + t3; t0 -= t2; t1 -= t3; b1 = ((t0 + t1) >> 8) * 181; b2 = ((t0 - t1) >> 8) * 181; block[8*0] = (a0 + b0) >> 17; block[8*1] = (a1 + b1) >> 17; block[8*2] = (a2 + b2) >> 17; block[8*3] = (a3 + b3) >> 17; block[8*4] = (a3 - b3) >> 17; block[8*5] = (a2 - b2) >> 17; block[8*6] = (a1 - b1) >> 17; block[8*7] = (a0 - b0) >> 17; } void mpeg2_idct_copy (int16_t * block, uint8_t * dest, const int stride) { int i; for (i = 0; i < 8; i++) idct_row (block + 8 * i); for (i = 0; i < 8; i++) idct_col (block + i); do { dest[0] = CLIP (block[0]); dest[1] = CLIP (block[1]); dest[2] = CLIP (block[2]); dest[3] = CLIP (block[3]); dest[4] = CLIP (block[4]); dest[5] = CLIP (block[5]); dest[6] = CLIP (block[6]); dest[7] = CLIP (block[7]); ((int32_t *)block)[0] = 0; ((int32_t *)block)[1] = 0; ((int32_t *)block)[2] = 0; ((int32_t *)block)[3] = 0; dest += stride; block += 8; } while (--i); } void mpeg2_idct_add (const int last, int16_t * block, uint8_t * dest, const int stride) { int i; if (last != 129 || (block[0] & (7 << 4)) == (4 << 4)) { for (i = 0; i < 8; i++) idct_row (block + 8 * i); for (i = 0; i < 8; i++) idct_col (block + i); do { dest[0] = CLIP (block[0] + dest[0]); dest[1] = CLIP (block[1] + dest[1]); dest[2] = CLIP (block[2] + dest[2]); dest[3] = CLIP (block[3] + dest[3]); dest[4] = CLIP (block[4] + dest[4]); dest[5] = CLIP (block[5] + dest[5]); dest[6] = CLIP (block[6] + dest[6]); dest[7] = CLIP (block[7] + dest[7]); ((int32_t *)block)[0] = 0; ((int32_t *)block)[1] = 0; ((int32_t *)block)[2] = 0; ((int32_t *)block)[3] = 0; dest += stride; block += 8; } while (--i); } else { int DC = (block[0] + 64) >> 7; block[0] = block[63] = 0; i = 8; do { dest[0] = CLIP (DC + dest[0]); dest[1] = CLIP (DC + dest[1]); dest[2] = CLIP (DC + dest[2]); dest[3] = CLIP (DC + dest[3]); dest[4] = CLIP (DC + dest[4]); dest[5] = CLIP (DC + dest[5]); dest[6] = CLIP (DC + dest[6]); dest[7] = CLIP (DC + dest[7]); dest += stride; } while (--i); } } #endif /* IDCT_ASM */ void mpeg2_idct_init (void) { int i, j; for (i = 0; i < 64; i++) { j = default_mpeg2_scan_norm[i]; mpeg2_scan_norm[i] = ((j & 0x36) >> 1) | ((j & 0x09) << 2); j = default_mpeg2_scan_alt[i]; mpeg2_scan_alt[i] = ((j & 0x36) >> 1) | ((j & 0x09) << 2); } }