FFmpeg
alacdsp_init.c
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 #include "libavutil/attributes.h"
20 #include "libavutil/x86/cpu.h"
21 #include "libavcodec/alacdsp.h"
22 #include "config.h"
23 
24 void ff_alac_decorrelate_stereo_sse4(int32_t *buffer[2], int nb_samples,
25  int decorr_shift, int decorr_left_weight);
26 void ff_alac_append_extra_bits_stereo_sse2(int32_t *buffer[2], int32_t *extra_bits_buffer[2],
27  int extra_bits, int channels, int nb_samples);
28 void ff_alac_append_extra_bits_mono_sse2(int32_t *buffer[2], int32_t *extra_bits_buffer[2],
29  int extra_bits, int channels, int nb_samples);
30 
32 {
33 #if HAVE_X86ASM
35 
36  if (EXTERNAL_SSE2(cpu_flags)) {
37  c->append_extra_bits[0] = ff_alac_append_extra_bits_mono_sse2;
38  c->append_extra_bits[1] = ff_alac_append_extra_bits_stereo_sse2;
39  }
40  if (EXTERNAL_SSE4(cpu_flags)) {
41  c->decorrelate_stereo = ff_alac_decorrelate_stereo_sse4;
42  }
43 #endif /* HAVE_X86ASM */
44 }
extra_bits
#define extra_bits(eb)
Definition: intrax8.c:125
cpu.h
ff_alac_decorrelate_stereo_sse4
void ff_alac_decorrelate_stereo_sse4(int32_t *buffer[2], int nb_samples, int decorr_shift, int decorr_left_weight)
av_get_cpu_flags
int av_get_cpu_flags(void)
Return the flags which specify extensions supported by the CPU.
Definition: cpu.c:98
cpu_flags
static atomic_int cpu_flags
Definition: cpu.c:50
alacdsp.h
av_cold
#define av_cold
Definition: attributes.h:90
channels
channels
Definition: aptx.h:33
ALACDSPContext
Definition: alacdsp.h:24
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
attributes.h
EXTERNAL_SSE2
#define EXTERNAL_SSE2(flags)
Definition: cpu.h:59
ff_alacdsp_init_x86
av_cold void ff_alacdsp_init_x86(ALACDSPContext *c)
Definition: alacdsp_init.c:31
ff_alac_append_extra_bits_mono_sse2
void ff_alac_append_extra_bits_mono_sse2(int32_t *buffer[2], int32_t *extra_bits_buffer[2], int extra_bits, int channels, int nb_samples)
EXTERNAL_SSE4
#define EXTERNAL_SSE4(flags)
Definition: cpu.h:68
buffer
the frame and frame reference mechanism is intended to as much as expensive copies of that data while still allowing the filters to produce correct results The data is stored in buffers represented by AVFrame structures Several references can point to the same frame buffer
Definition: filter_design.txt:49
int32_t
int32_t
Definition: audioconvert.c:56
ff_alac_append_extra_bits_stereo_sse2
void ff_alac_append_extra_bits_stereo_sse2(int32_t *buffer[2], int32_t *extra_bits_buffer[2], int extra_bits, int channels, int nb_samples)