ffmpeg/libavutil/x86/pixelutils_init.c
Peter Cordes 9e5687adf2 pixelutils: Comment on (lack of) sad_8x8_sse2
Signed-off-by: Peter Cordes <peter@cordes.ca>
2015-03-04 21:58:53 +01:00

65 lines
2.7 KiB
C

/*
* This file is part of FFmpeg.
*
* FFmpeg 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 2.1 of the License, or (at your option) any later version.
*
* FFmpeg 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 FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "config.h"
#include "pixelutils.h"
#include "cpu.h"
int ff_pixelutils_sad_8x8_mmx(const uint8_t *src1, ptrdiff_t stride1,
const uint8_t *src2, ptrdiff_t stride2);
int ff_pixelutils_sad_8x8_mmxext(const uint8_t *src1, ptrdiff_t stride1,
const uint8_t *src2, ptrdiff_t stride2);
int ff_pixelutils_sad_16x16_mmxext(const uint8_t *src1, ptrdiff_t stride1,
const uint8_t *src2, ptrdiff_t stride2);
int ff_pixelutils_sad_16x16_sse2(const uint8_t *src1, ptrdiff_t stride1,
const uint8_t *src2, ptrdiff_t stride2);
int ff_pixelutils_sad_a_16x16_sse2(const uint8_t *src1, ptrdiff_t stride1,
const uint8_t *src2, ptrdiff_t stride2);
int ff_pixelutils_sad_u_16x16_sse2(const uint8_t *src1, ptrdiff_t stride1,
const uint8_t *src2, ptrdiff_t stride2);
void ff_pixelutils_sad_init_x86(av_pixelutils_sad_fn *sad, int aligned)
{
int cpu_flags = av_get_cpu_flags();
if (EXTERNAL_MMX(cpu_flags)) {
sad[2] = ff_pixelutils_sad_8x8_mmx;
}
// The best way to use SSE2 would be to do 2 SADs in parallel,
// but we'd have to modify the pixelutils API to return SIMD functions.
// It's probably not faster to shuffle data around
// to get two lines of 8 pixels into a single 16byte register,
// so just use the MMX 8x8 version even when SSE2 is available.
if (EXTERNAL_MMXEXT(cpu_flags)) {
sad[2] = ff_pixelutils_sad_8x8_mmxext;
sad[3] = ff_pixelutils_sad_16x16_mmxext;
}
if (EXTERNAL_SSE2(cpu_flags)) {
switch (aligned) {
case 0: sad[3] = ff_pixelutils_sad_16x16_sse2; break; // src1 unaligned, src2 unaligned
case 1: sad[3] = ff_pixelutils_sad_u_16x16_sse2; break; // src1 aligned, src2 unaligned
case 2: sad[3] = ff_pixelutils_sad_a_16x16_sse2; break; // src1 aligned, src2 aligned
}
}
}