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Diffstat (limited to 'src/video_dec/libmpeg2/idct.c')
-rw-r--r-- | src/video_dec/libmpeg2/idct.c | 348 |
1 files changed, 348 insertions, 0 deletions
diff --git a/src/video_dec/libmpeg2/idct.c b/src/video_dec/libmpeg2/idct.c new file mode 100644 index 000000000..9f216db58 --- /dev/null +++ b/src/video_dec/libmpeg2/idct.c @@ -0,0 +1,348 @@ +/* + * idct.c + * Copyright (C) 2000-2002 Michel Lespinasse <walken@zoy.org> + * Copyright (C) 1999-2000 Aaron Holtzman <aholtzma@ess.engr.uvic.ca> + * + * Portions of this code are from the MPEG software simulation group + * idct implementation. This code will be replaced with a new + * implementation soon. + * + * 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 + */ + +/**********************************************************/ +/* inverse two dimensional DCT, Chen-Wang algorithm */ +/* (cf. IEEE ASSP-32, pp. 803-816, Aug. 1984) */ +/* 32-bit integer arithmetic (8 bit coefficients) */ +/* 11 mults, 29 adds per DCT */ +/* sE, 18.8.91 */ +/**********************************************************/ +/* coefficients extended to 12 bit for IEEE1180-1990 */ +/* compliance sE, 2.1.94 */ +/**********************************************************/ + +/* this code assumes >> to be a two's-complement arithmetic */ +/* right shift: (-2)>>1 == -1 , (-3)>>1 == -2 */ + +#include "config.h" + +#include <stdio.h> +#include <stdlib.h> +#include <inttypes.h> + +#include "mpeg2_internal.h" +#include <xine/xineutils.h> + +#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) */ + +/* idct main entry points */ +void (* mpeg2_idct_copy) (int16_t * block, uint8_t * dest, int stride); +void (* mpeg2_idct_add) (int16_t * block, uint8_t * dest, int stride); +void (* mpeg2_idct) (int16_t * block); +void (* mpeg2_zero_block) (int16_t * block); + +static uint8_t clip_lut[1024]; +#define CLIP(i) ((clip_lut+384)[ (i)]) + +/* row (horizontal) IDCT + * + * 7 pi 1 + * dst[k] = sum c[l] * src[l] * cos ( -- * ( k + - ) * l ) + * l=0 8 2 + * + * where: c[0] = 128 + * c[1..7] = 128*sqrt (2) + */ + +static void inline idct_row (int16_t * block) +{ + int x0, x1, x2, x3, x4, x5, x6, x7, x8; + + x1 = block[4] << 11; + x2 = block[6]; + x3 = block[2]; + x4 = block[1]; + x5 = block[7]; + x6 = block[5]; + x7 = block[3]; + + /* shortcut */ + if (! (x1 | x2 | x3 | x4 | x5 | x6 | x7 )) { + block[0] = block[1] = block[2] = block[3] = block[4] = + block[5] = block[6] = block[7] = block[0]<<3; + return; + } + + x0 = (block[0] << 11) + 128; /* for proper rounding in the fourth stage */ + + /* first stage */ + x8 = W7 * (x4 + x5); + x4 = x8 + (W1 - W7) * x4; + x5 = x8 - (W1 + W7) * x5; + x8 = W3 * (x6 + x7); + x6 = x8 - (W3 - W5) * x6; + x7 = x8 - (W3 + W5) * x7; + + /* second stage */ + x8 = x0 + x1; + x0 -= x1; + x1 = W6 * (x3 + x2); + x2 = x1 - (W2 + W6) * x2; + x3 = x1 + (W2 - W6) * x3; + x1 = x4 + x6; + x4 -= x6; + x6 = x5 + x7; + x5 -= x7; + + /* third stage */ + x7 = x8 + x3; + x8 -= x3; + x3 = x0 + x2; + x0 -= x2; + x2 = (181 * (x4 + x5) + 128) >> 8; + x4 = (181 * (x4 - x5) + 128) >> 8; + + /* fourth stage */ + block[0] = (x7 + x1) >> 8; + block[1] = (x3 + x2) >> 8; + block[2] = (x0 + x4) >> 8; + block[3] = (x8 + x6) >> 8; + block[4] = (x8 - x6) >> 8; + block[5] = (x0 - x4) >> 8; + block[6] = (x3 - x2) >> 8; + block[7] = (x7 - x1) >> 8; +} + +/* column (vertical) IDCT + * + * 7 pi 1 + * dst[8*k] = sum c[l] * src[8*l] * cos ( -- * ( k + - ) * l ) + * l=0 8 2 + * + * where: c[0] = 1/1024 + * c[1..7] = (1/1024)*sqrt (2) + */ + +static void inline idct_col (int16_t *block) +{ + int x0, x1, x2, x3, x4, x5, x6, x7, x8; + + /* shortcut */ + x1 = block [8*4] << 8; + x2 = block [8*6]; + x3 = block [8*2]; + x4 = block [8*1]; + x5 = block [8*7]; + x6 = block [8*5]; + x7 = block [8*3]; + +#if 0 + if (! (x1 | x2 | x3 | x4 | x5 | x6 | x7 )) { + block[8*0] = block[8*1] = block[8*2] = block[8*3] = block[8*4] = + block[8*5] = block[8*6] = block[8*7] = (block[8*0] + 32) >> 6; + return; + } +#endif + + x0 = (block[8*0] << 8) + 8192; + + /* first stage */ + x8 = W7 * (x4 + x5) + 4; + x4 = (x8 + (W1 - W7) * x4) >> 3; + x5 = (x8 - (W1 + W7) * x5) >> 3; + x8 = W3 * (x6 + x7) + 4; + x6 = (x8 - (W3 - W5) * x6) >> 3; + x7 = (x8 - (W3 + W5) * x7) >> 3; + + /* second stage */ + x8 = x0 + x1; + x0 -= x1; + x1 = W6 * (x3 + x2) + 4; + x2 = (x1 - (W2 + W6) * x2) >> 3; + x3 = (x1 + (W2 - W6) * x3) >> 3; + x1 = x4 + x6; + x4 -= x6; + x6 = x5 + x7; + x5 -= x7; + + /* third stage */ + x7 = x8 + x3; + x8 -= x3; + x3 = x0 + x2; + x0 -= x2; + x2 = (181 * (x4 + x5) + 128) >> 8; + x4 = (181 * (x4 - x5) + 128) >> 8; + + /* fourth stage */ + block[8*0] = (x7 + x1) >> 14; + block[8*1] = (x3 + x2) >> 14; + block[8*2] = (x0 + x4) >> 14; + block[8*3] = (x8 + x6) >> 14; + block[8*4] = (x8 - x6) >> 14; + block[8*5] = (x0 - x4) >> 14; + block[8*6] = (x3 - x2) >> 14; + block[8*7] = (x7 - x1) >> 14; +} + +static void mpeg2_idct_copy_c (int16_t * block, uint8_t * dest, 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); + + i = 8; + 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]); + + block[0] = 0; block[1] = 0; block[2] = 0; block[3] = 0; + block[4] = 0; block[5] = 0; block[6] = 0; block[7] = 0; + + dest += stride; + block += 8; + } while (--i); +} + +static void mpeg2_idct_add_c (int16_t * block, uint8_t * dest, 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); + + i = 8; + 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]); + + block[0] = 0; block[1] = 0; block[2] = 0; block[3] = 0; + block[4] = 0; block[5] = 0; block[6] = 0; block[7] = 0; + + dest += stride; + block += 8; + } while (--i); +} + +static void mpeg2_idct_c (int16_t * block) +{ + int i; + + for (i = 0; i < 8; i++) + idct_row (block + 8 * i); + + for (i = 0; i < 8; i++) + idct_col (block + i); +} + +static void mpeg2_zero_block_c (int16_t * wblock) +{ + memset( wblock, 0, sizeof(int16_t) * 64 ); +} + +void mpeg2_idct_init (uint32_t mm_accel) +{ + mpeg2_zero_block = mpeg2_zero_block_c; + +#if defined(ARCH_X86) || defined(ARCH_X86_64) + if (mm_accel & MM_ACCEL_X86_MMXEXT) { +#ifdef LOG + fprintf (stderr, "Using MMXEXT for IDCT transform\n"); +#endif + mpeg2_idct_copy = mpeg2_idct_copy_mmxext; + mpeg2_idct_add = mpeg2_idct_add_mmxext; + mpeg2_idct = mpeg2_idct_mmxext; + mpeg2_zero_block = mpeg2_zero_block_mmx; + mpeg2_idct_mmx_init (); + } else if (mm_accel & MM_ACCEL_X86_MMX) { +#ifdef LOG + fprintf (stderr, "Using MMX for IDCT transform\n"); +#endif + mpeg2_idct_copy = mpeg2_idct_copy_mmx; + mpeg2_idct_add = mpeg2_idct_add_mmx; + mpeg2_idct = mpeg2_idct_mmx; + mpeg2_zero_block = mpeg2_zero_block_mmx; + mpeg2_idct_mmx_init (); + } else +#endif +#if defined (ARCH_PPC) && defined (ENABLE_ALTIVEC) + if (mm_accel & MM_ACCEL_PPC_ALTIVEC) { +#ifdef LOG + fprintf (stderr, "Using altivec for IDCT transform\n"); +#endif + mpeg2_idct_copy = mpeg2_idct_copy_altivec; + mpeg2_idct_add = mpeg2_idct_add_altivec; + mpeg2_idct_altivec_init (); + mpeg2_idct = mpeg2_idct_c; + } else +#endif +#ifdef LIBMPEG2_MLIB + if (mm_accel & MM_ACCEL_MLIB) { + char * env_var; + + env_var = getenv ("MLIB_NON_IEEE"); + + mpeg2_idct = mpeg2_idct_mlib; + if (env_var == NULL) { +#ifdef LOG + fprintf (stderr, "Using mlib for IDCT transform\n"); +#endif + mpeg2_idct_add = mpeg2_idct_add_mlib; + } else { + fprintf (stderr, "Using non-IEEE mlib for IDCT transform\n"); + mpeg2_idct_add = mpeg2_idct_add_mlib_non_ieee; + } + mpeg2_idct_copy = mpeg2_idct_copy_mlib_non_ieee; + } else +#endif + { + int i; + +#ifdef LOG + fprintf (stderr, "No accelerated IDCT transform found\n"); +#endif + mpeg2_idct_copy = mpeg2_idct_copy_c; + mpeg2_idct_add = mpeg2_idct_add_c; + mpeg2_idct = mpeg2_idct_c; + for (i = -384; i < 640; i++) + clip_lut[i+384] = (i < 0) ? 0 : ((i > 255) ? 255 : i); + } +} |