diff options
author | Falk Hüffner <mellum@users.sourceforge.net> | 2002-10-12 03:01:16 +0400 |
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committer | Falk Hüffner <mellum@users.sourceforge.net> | 2002-10-12 03:01:16 +0400 |
commit | 8b313a47871a02146ab093b3eff31636413dea13 (patch) | |
tree | 2e8ffad9c3fe3d8d12e270a46c496ab15e7dd2fc /libavcodec/alpha/simple_idct_alpha.c | |
parent | bb15f7fdd5c0c5f200f89fc9e47a3ff94e567e36 (diff) |
Move Alpha optimized IDCT to own file. Based on a patch by MÃ¥ns
Rullgård <mru@users.sourceforge.net>.
I've left out the idctCol2 part, because W4 has recently been decreed
to be 16383, and also I doubt it will give a noticeable speedup.
Originally committed as revision 1029 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec/alpha/simple_idct_alpha.c')
-rw-r--r-- | libavcodec/alpha/simple_idct_alpha.c | 306 |
1 files changed, 306 insertions, 0 deletions
diff --git a/libavcodec/alpha/simple_idct_alpha.c b/libavcodec/alpha/simple_idct_alpha.c new file mode 100644 index 0000000000..31677184e0 --- /dev/null +++ b/libavcodec/alpha/simple_idct_alpha.c @@ -0,0 +1,306 @@ +/* + * Simple IDCT (Alpha optimized) + * + * Copyright (c) 2001 Michael Niedermayer <michaelni@gmx.at> + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + * based upon some outcommented c code from mpeg2dec (idct_mmx.c + * written by Aaron Holtzman <aholtzma@ess.engr.uvic.ca>) + * + * Alpha optimiziations by Måns Rullgård <mru@users.sourceforge.net> + * and Falk Hueffner <falk@debian.org> + */ + +#include "asm.h" +#include "../dsputil.h" + +// cos(i * M_PI / 16) * sqrt(2) * (1 << 14) +// W4 is actually exactly 16384, but using 16383 works around +// accumulating rounding errors for some encoders +#define W1 ((int_fast32_t) 22725) +#define W2 ((int_fast32_t) 21407) +#define W3 ((int_fast32_t) 19266) +#define W4 ((int_fast32_t) 16383) +#define W5 ((int_fast32_t) 12873) +#define W6 ((int_fast32_t) 8867) +#define W7 ((int_fast32_t) 4520) +#define ROW_SHIFT 11 +#define COL_SHIFT 20 + +/* 0: all entries 0, 1: only first entry nonzero, 2: otherwise */ +static inline int idct_row(DCTELEM *row) +{ + int_fast32_t a0, a1, a2, a3, b0, b1, b2, b3, t; + uint64_t l, r; + l = ldq(row); + r = ldq(row + 4); + + if (l == 0 && r == 0) + return 0; + + a0 = W4 * sextw(l) + (1 << (ROW_SHIFT - 1)); + + if (((l & ~0xffffUL) | r) == 0) { + a0 >>= ROW_SHIFT; + a0 = (uint16_t) a0; + a0 |= a0 << 16; + a0 |= a0 << 32; + + stq(a0, row); + stq(a0, row + 4); + return 1; + } + + a1 = a0; + a2 = a0; + a3 = a0; + + t = extwl(l, 4); /* row[2] */ + if (t != 0) { + t = sextw(t); + a0 += W2 * t; + a1 += W6 * t; + a2 -= W6 * t; + a3 -= W2 * t; + } + + t = extwl(r, 0); /* row[4] */ + if (t != 0) { + t = sextw(t); + a0 += W4 * t; + a1 -= W4 * t; + a2 -= W4 * t; + a3 += W4 * t; + } + + t = extwl(r, 4); /* row[6] */ + if (t != 0) { + t = sextw(t); + a0 += W6 * t; + a1 -= W2 * t; + a2 += W2 * t; + a3 -= W6 * t; + } + + t = extwl(l, 2); /* row[1] */ + if (t != 0) { + t = sextw(t); + b0 = W1 * t; + b1 = W3 * t; + b2 = W5 * t; + b3 = W7 * t; + } else { + b0 = 0; + b1 = 0; + b2 = 0; + b3 = 0; + } + + t = extwl(l, 6); /* row[3] */ + if (t) { + t = sextw(t); + b0 += W3 * t; + b1 -= W7 * t; + b2 -= W1 * t; + b3 -= W5 * t; + } + + + t = extwl(r, 2); /* row[5] */ + if (t) { + t = sextw(t); + b0 += W5 * t; + b1 -= W1 * t; + b2 += W7 * t; + b3 += W3 * t; + } + + t = extwl(r, 6); /* row[7] */ + if (t) { + t = sextw(t); + b0 += W7 * t; + b1 -= W5 * t; + b2 += W3 * t; + b3 -= W1 * t; + } + + row[0] = (a0 + b0) >> ROW_SHIFT; + row[1] = (a1 + b1) >> ROW_SHIFT; + row[2] = (a2 + b2) >> ROW_SHIFT; + row[3] = (a3 + b3) >> ROW_SHIFT; + row[4] = (a3 - b3) >> ROW_SHIFT; + row[5] = (a2 - b2) >> ROW_SHIFT; + row[6] = (a1 - b1) >> ROW_SHIFT; + row[7] = (a0 - b0) >> ROW_SHIFT; + + return 2; +} + +static inline void idct_col(DCTELEM *col) +{ + int_fast32_t a0, a1, a2, a3, b0, b1, b2, b3; + + col[0] += (1 << (COL_SHIFT - 1)) / W4; + + a0 = W4 * col[8 * 0]; + a1 = W4 * col[8 * 0]; + a2 = W4 * col[8 * 0]; + a3 = W4 * col[8 * 0]; + + if (col[8 * 2]) { + a0 += W2 * col[8 * 2]; + a1 += W6 * col[8 * 2]; + a2 -= W6 * col[8 * 2]; + a3 -= W2 * col[8 * 2]; + } + + if (col[8 * 4]) { + a0 += W4 * col[8 * 4]; + a1 -= W4 * col[8 * 4]; + a2 -= W4 * col[8 * 4]; + a3 += W4 * col[8 * 4]; + } + + if (col[8 * 6]) { + a0 += W6 * col[8 * 6]; + a1 -= W2 * col[8 * 6]; + a2 += W2 * col[8 * 6]; + a3 -= W6 * col[8 * 6]; + } + + if (col[8 * 1]) { + b0 = W1 * col[8 * 1]; + b1 = W3 * col[8 * 1]; + b2 = W5 * col[8 * 1]; + b3 = W7 * col[8 * 1]; + } else { + b0 = 0; + b1 = 0; + b2 = 0; + b3 = 0; + } + + if (col[8 * 3]) { + b0 += W3 * col[8 * 3]; + b1 -= W7 * col[8 * 3]; + b2 -= W1 * col[8 * 3]; + b3 -= W5 * col[8 * 3]; + } + + if (col[8 * 5]) { + b0 += W5 * col[8 * 5]; + b1 -= W1 * col[8 * 5]; + b2 += W7 * col[8 * 5]; + b3 += W3 * col[8 * 5]; + } + + if (col[8 * 7]) { + b0 += W7 * col[8 * 7]; + b1 -= W5 * col[8 * 7]; + b2 += W3 * col[8 * 7]; + b3 -= W1 * col[8 * 7]; + } + + col[8 * 0] = (a0 + b0) >> COL_SHIFT; + col[8 * 7] = (a0 - b0) >> COL_SHIFT; + col[8 * 1] = (a1 + b1) >> COL_SHIFT; + col[8 * 6] = (a1 - b1) >> COL_SHIFT; + col[8 * 2] = (a2 + b2) >> COL_SHIFT; + col[8 * 5] = (a2 - b2) >> COL_SHIFT; + col[8 * 3] = (a3 + b3) >> COL_SHIFT; + col[8 * 4] = (a3 - b3) >> COL_SHIFT; +} + +/* If all rows but the first one are zero after row transformation, + all rows will be identical after column transformation. */ +static inline void idct_col2(DCTELEM *col) +{ + int i; + uint64_t l, r; + uint64_t *lcol = (uint64_t *) col; + + for (i = 0; i < 8; ++i) { + int_fast32_t a0 = col[0] + (1 << (COL_SHIFT - 1)) / W4; + + a0 *= W4; + col[0] = a0 >> COL_SHIFT; + ++col; + } + + l = lcol[0]; + r = lcol[1]; + lcol[ 2] = l; lcol[ 3] = r; + lcol[ 4] = l; lcol[ 5] = r; + lcol[ 6] = l; lcol[ 7] = r; + lcol[ 8] = l; lcol[ 9] = r; + lcol[10] = l; lcol[11] = r; + lcol[12] = l; lcol[13] = r; + lcol[14] = l; lcol[15] = r; +} + +void simple_idct_axp(DCTELEM *block) +{ + + int i; + int rowsZero = 1; /* all rows except row 0 zero */ + int rowsConstant = 1; /* all rows consist of a constant value */ + + for (i = 0; i < 8; i++) { + int sparseness = idct_row(block + 8 * i); + + if (i > 0 && sparseness > 0) + rowsZero = 0; + if (sparseness == 2) + rowsConstant = 0; + } + + if (rowsZero) { + idct_col2(block); + } else if (rowsConstant) { + uint64_t *lblock = (uint64_t *) block; + + idct_col(block); + for (i = 0; i < 8; i += 2) { + uint64_t v = (uint16_t) block[i * 8]; + uint64_t w = (uint16_t) block[i * 8 + 8]; + + v |= v << 16; + w |= w << 16; + v |= v << 32; + w |= w << 32; + lblock[0] = v; + lblock[1] = v; + lblock[2] = w; + lblock[3] = w; + lblock += 4; + } + } else { + for (i = 0; i < 8; i++) + idct_col(block + i); + } +} + +void simple_idct_put_axp(uint8_t *dest, int line_size, DCTELEM *block) +{ + simple_idct_axp(block); + put_pixels_clamped(block, dest, line_size); +} + +void simple_idct_add_axp(uint8_t *dest, int line_size, DCTELEM *block) +{ + simple_idct_axp(block); + add_pixels_clamped(block, dest, line_size); +} |