From 7a1d6ddd2c6b2d66fbc1afa584cf506930a26453 Mon Sep 17 00:00:00 2001 From: Pascal Massimino Date: Wed, 27 Aug 2014 02:58:10 +0200 Subject: xvid: Add C IDCT Thanks to Pascal Massimino and Michael Militzer for relicensing as LGPL. Signed-off-by: Diego Biurrun --- libavcodec/xvididct.c | 322 +++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 317 insertions(+), 5 deletions(-) (limited to 'libavcodec/xvididct.c') diff --git a/libavcodec/xvididct.c b/libavcodec/xvididct.c index 0562fdbb63..ca89703233 100644 --- a/libavcodec/xvididct.c +++ b/libavcodec/xvididct.c @@ -1,4 +1,8 @@ /* + * Xvid MPEG-4 IDCT + * + * Copyright (C) 2006-2011 Xvid Solutions GmbH + * * This file is part of Libav. * * Libav is free software; you can redistribute it and/or @@ -16,23 +20,331 @@ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ +/** + * @file + * Walken IDCT + * Alternative IDCT implementation for decoding compatibility. + * + * @author Skal + * @note This C version is not the original IDCT, but a modified one that + * yields the same error profile as the MMX/MMXEXT/SSE2 versions. + */ + #include "config.h" #include "libavutil/attributes.h" #include "avcodec.h" #include "idctdsp.h" #include "xvididct.h" +#define ROW_SHIFT 11 +#define COL_SHIFT 6 + +// #define FIX(x) (int)((x) * (1 << ROW_SHIFT)) +#define RND0 65536 // 1 << (COL_SHIFT + ROW_SHIFT - 1); +#define RND1 3597 // FIX (1.75683487303); +#define RND2 2260 // FIX (1.10355339059); +#define RND3 1203 // FIX (0.587788325588); +#define RND4 0 +#define RND5 120 // FIX (0.058658283817); +#define RND6 512 // FIX (0.25); +#define RND7 512 // FIX (0.25); + +static const int TAB04[] = { 22725, 21407, 19266, 16384, 12873, 8867, 4520 }; +static const int TAB17[] = { 31521, 29692, 26722, 22725, 17855, 12299, 6270 }; +static const int TAB26[] = { 29692, 27969, 25172, 21407, 16819, 11585, 5906 }; +static const int TAB35[] = { 26722, 25172, 22654, 19266, 15137, 10426, 5315 }; + +static int idct_row(short *in, const int *const tab, int rnd) +{ + const int c1 = tab[0]; + const int c2 = tab[1]; + const int c3 = tab[2]; + const int c4 = tab[3]; + const int c5 = tab[4]; + const int c6 = tab[5]; + const int c7 = tab[6]; + + const int right = in[5] | in[6] | in[7]; + const int left = in[1] | in[2] | in[3]; + if (!(right | in[4])) { + const int k = c4 * in[0] + rnd; + if (left) { + const int a0 = k + c2 * in[2]; + const int a1 = k + c6 * in[2]; + const int a2 = k - c6 * in[2]; + const int a3 = k - c2 * in[2]; + + const int b0 = c1 * in[1] + c3 * in[3]; + const int b1 = c3 * in[1] - c7 * in[3]; + const int b2 = c5 * in[1] - c1 * in[3]; + const int b3 = c7 * in[1] - c5 * in[3]; + + in[0] = (a0 + b0) >> ROW_SHIFT; + in[1] = (a1 + b1) >> ROW_SHIFT; + in[2] = (a2 + b2) >> ROW_SHIFT; + in[3] = (a3 + b3) >> ROW_SHIFT; + in[4] = (a3 - b3) >> ROW_SHIFT; + in[5] = (a2 - b2) >> ROW_SHIFT; + in[6] = (a1 - b1) >> ROW_SHIFT; + in[7] = (a0 - b0) >> ROW_SHIFT; + } else { + const int a0 = k >> ROW_SHIFT; + if (a0) { + in[0] = + in[1] = + in[2] = + in[3] = + in[4] = + in[5] = + in[6] = + in[7] = a0; + } else + return 0; + } + } else if (!(left | right)) { + const int a0 = (rnd + c4 * (in[0] + in[4])) >> ROW_SHIFT; + const int a1 = (rnd + c4 * (in[0] - in[4])) >> ROW_SHIFT; + + in[0] = a0; + in[3] = a0; + in[4] = a0; + in[7] = a0; + in[1] = a1; + in[2] = a1; + in[5] = a1; + in[6] = a1; + } else { + const int k = c4 * in[0] + rnd; + const int a0 = k + c2 * in[2] + c4 * in[4] + c6 * in[6]; + const int a1 = k + c6 * in[2] - c4 * in[4] - c2 * in[6]; + const int a2 = k - c6 * in[2] - c4 * in[4] + c2 * in[6]; + const int a3 = k - c2 * in[2] + c4 * in[4] - c6 * in[6]; + + const int b0 = c1 * in[1] + c3 * in[3] + c5 * in[5] + c7 * in[7]; + const int b1 = c3 * in[1] - c7 * in[3] - c1 * in[5] - c5 * in[7]; + const int b2 = c5 * in[1] - c1 * in[3] + c7 * in[5] + c3 * in[7]; + const int b3 = c7 * in[1] - c5 * in[3] + c3 * in[5] - c1 * in[7]; + + in[0] = (a0 + b0) >> ROW_SHIFT; + in[1] = (a1 + b1) >> ROW_SHIFT; + in[2] = (a2 + b2) >> ROW_SHIFT; + in[3] = (a3 + b3) >> ROW_SHIFT; + in[4] = (a3 - b3) >> ROW_SHIFT; + in[5] = (a2 - b2) >> ROW_SHIFT; + in[6] = (a1 - b1) >> ROW_SHIFT; + in[7] = (a0 - b0) >> ROW_SHIFT; + } + return 1; +} + +#define TAN1 0x32EC +#define TAN2 0x6A0A +#define TAN3 0xAB0E +#define SQRT2 0x5A82 + +#define MULT(c, x, n) (((c) * (x)) >> (n)) +// 12b version => #define MULT(c,x, n) ((((c) >> 3) * (x)) >> ((n) - 3)) +// 12b zero-testing version: + +#define BUTTERFLY(a, b, tmp) \ + (tmp) = (a) + (b); \ + (b) = (a) - (b); \ + (a) = (tmp) + +#define LOAD_BUTTERFLY(m1, m2, a, b, tmp, s) \ + (m1) = (s)[(a)] + (s)[(b)]; \ + (m2) = (s)[(a)] - (s)[(b)] + +static void idct_col_8(short *const in) +{ + int mm0, mm1, mm2, mm3, mm4, mm5, mm6, mm7, spill; + + // odd + + mm4 = (int) in[7 * 8]; + mm5 = (int) in[5 * 8]; + mm6 = (int) in[3 * 8]; + mm7 = (int) in[1 * 8]; + + mm0 = MULT(TAN1, mm4, 16) + mm7; + mm1 = MULT(TAN1, mm7, 16) - mm4; + mm2 = MULT(TAN3, mm5, 16) + mm6; + mm3 = MULT(TAN3, mm6, 16) - mm5; + + mm7 = mm0 + mm2; + mm4 = mm1 - mm3; + mm0 = mm0 - mm2; + mm1 = mm1 + mm3; + mm6 = mm0 + mm1; + mm5 = mm0 - mm1; + mm5 = 2 * MULT(SQRT2, mm5, 16); // 2*sqrt2 + mm6 = 2 * MULT(SQRT2, mm6, 16); // Watch out: precision loss but done to match + // the pmulhw used in MMX/MMXEXT/SSE2 versions + + // even + + mm1 = (int) in[2 * 8]; + mm2 = (int) in[6 * 8]; + mm3 = MULT(TAN2, mm2, 16) + mm1; + mm2 = MULT(TAN2, mm1, 16) - mm2; + + LOAD_BUTTERFLY(mm0, mm1, 0 * 8, 4 * 8, spill, in); + + BUTTERFLY(mm0, mm3, spill); + BUTTERFLY(mm0, mm7, spill); + in[8 * 0] = (int16_t) (mm0 >> COL_SHIFT); + in[8 * 7] = (int16_t) (mm7 >> COL_SHIFT); + BUTTERFLY(mm3, mm4, mm0); + in[8 * 3] = (int16_t) (mm3 >> COL_SHIFT); + in[8 * 4] = (int16_t) (mm4 >> COL_SHIFT); + + BUTTERFLY(mm1, mm2, mm0); + BUTTERFLY(mm1, mm6, mm0); + in[8 * 1] = (int16_t) (mm1 >> COL_SHIFT); + in[8 * 6] = (int16_t) (mm6 >> COL_SHIFT); + BUTTERFLY(mm2, mm5, mm0); + in[8 * 2] = (int16_t) (mm2 >> COL_SHIFT); + in[8 * 5] = (int16_t) (mm5 >> COL_SHIFT); +} + +static void idct_col_4(short *const in) +{ + int mm0, mm1, mm2, mm3, mm4, mm5, mm6, mm7, spill; + + // odd + + mm0 = (int) in[1 * 8]; + mm2 = (int) in[3 * 8]; + + mm1 = MULT(TAN1, mm0, 16); + mm3 = MULT(TAN3, mm2, 16); + + mm7 = mm0 + mm2; + mm4 = mm1 - mm3; + mm0 = mm0 - mm2; + mm1 = mm1 + mm3; + mm6 = mm0 + mm1; + mm5 = mm0 - mm1; + mm6 = 2 * MULT(SQRT2, mm6, 16); // 2*sqrt2 + mm5 = 2 * MULT(SQRT2, mm5, 16); + + // even + + mm0 = mm1 = (int) in[0 * 8]; + mm3 = (int) in[2 * 8]; + mm2 = MULT(TAN2, mm3, 16); + + BUTTERFLY(mm0, mm3, spill); + BUTTERFLY(mm0, mm7, spill); + in[8 * 0] = (int16_t) (mm0 >> COL_SHIFT); + in[8 * 7] = (int16_t) (mm7 >> COL_SHIFT); + BUTTERFLY(mm3, mm4, mm0); + in[8 * 3] = (int16_t) (mm3 >> COL_SHIFT); + in[8 * 4] = (int16_t) (mm4 >> COL_SHIFT); + + BUTTERFLY(mm1, mm2, mm0); + BUTTERFLY(mm1, mm6, mm0); + in[8 * 1] = (int16_t) (mm1 >> COL_SHIFT); + in[8 * 6] = (int16_t) (mm6 >> COL_SHIFT); + BUTTERFLY(mm2, mm5, mm0); + in[8 * 2] = (int16_t) (mm2 >> COL_SHIFT); + in[8 * 5] = (int16_t) (mm5 >> COL_SHIFT); +} + +static void idct_col_3(short *const in) +{ + int mm0, mm1, mm2, mm3, mm4, mm5, mm6, mm7, spill; + + // odd + + mm7 = (int) in[1 * 8]; + mm4 = MULT(TAN1, mm7, 16); + + mm6 = mm7 + mm4; + mm5 = mm7 - mm4; + mm6 = 2 * MULT(SQRT2, mm6, 16); // 2*sqrt2 + mm5 = 2 * MULT(SQRT2, mm5, 16); + + // even + + mm0 = mm1 = (int) in[0 * 8]; + mm3 = (int) in[2 * 8]; + mm2 = MULT(TAN2, mm3, 16); + + BUTTERFLY(mm0, mm3, spill); + BUTTERFLY(mm0, mm7, spill); + in[8 * 0] = (int16_t) (mm0 >> COL_SHIFT); + in[8 * 7] = (int16_t) (mm7 >> COL_SHIFT); + BUTTERFLY(mm3, mm4, mm0); + in[8 * 3] = (int16_t) (mm3 >> COL_SHIFT); + in[8 * 4] = (int16_t) (mm4 >> COL_SHIFT); + + BUTTERFLY(mm1, mm2, mm0); + BUTTERFLY(mm1, mm6, mm0); + in[8 * 1] = (int16_t) (mm1 >> COL_SHIFT); + in[8 * 6] = (int16_t) (mm6 >> COL_SHIFT); + BUTTERFLY(mm2, mm5, mm0); + in[8 * 2] = (int16_t) (mm2 >> COL_SHIFT); + in[8 * 5] = (int16_t) (mm5 >> COL_SHIFT); +} + +void ff_xvid_idct(int16_t *const in) +{ + int i, rows = 0x07; + + idct_row(in + 0 * 8, TAB04, RND0); + idct_row(in + 1 * 8, TAB17, RND1); + idct_row(in + 2 * 8, TAB26, RND2); + if (idct_row(in + 3 * 8, TAB35, RND3)) + rows |= 0x08; + if (idct_row(in + 4 * 8, TAB04, RND4)) + rows |= 0x10; + if (idct_row(in + 5 * 8, TAB35, RND5)) + rows |= 0x20; + if (idct_row(in + 6 * 8, TAB26, RND6)) + rows |= 0x40; + if (idct_row(in + 7 * 8, TAB17, RND7)) + rows |= 0x80; + + if (rows & 0xF0) { + for (i = 0; i < 8; i++) + idct_col_8(in + i); + } else if (rows & 0x08) { + for (i = 0; i < 8; i++) + idct_col_4(in + i); + } else { + for (i = 0; i < 8; i++) + idct_col_3(in + i); + } +} + +static void xvid_idct_put(uint8_t *dest, int line_size, int16_t *block) +{ + ff_xvid_idct(block); + ff_put_pixels_clamped(block, dest, line_size); +} + +static void xvid_idct_add(uint8_t *dest, int line_size, int16_t *block) +{ + ff_xvid_idct(block); + ff_add_pixels_clamped(block, dest, line_size); +} + av_cold void ff_xvid_idct_init(IDCTDSPContext *c, AVCodecContext *avctx) { const unsigned high_bit_depth = avctx->bits_per_raw_sample > 8; - if (high_bit_depth || - !(avctx->idct_algo == FF_IDCT_AUTO || - avctx->idct_algo == FF_IDCT_XVID)) - return; + if (!high_bit_depth && + (avctx->idct_algo == FF_IDCT_AUTO || + avctx->idct_algo == FF_IDCT_XVID)) { + c->idct_put = xvid_idct_put; + c->idct_add = xvid_idct_add; + c->idct = ff_xvid_idct; + c->perm_type = FF_IDCT_PERM_NONE; + } if (ARCH_X86) - ff_xvid_idct_init_x86(c); + ff_xvid_idct_init_x86(c, avctx, high_bit_depth); ff_init_scantable_permutation(c->idct_permutation, c->perm_type); 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