FFmpeg
fdctdsp.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 "avcodec.h"
21 #include "faandct.h"
22 #include "fdctdsp.h"
23 #include "config.h"
24 
26 {
27  av_unused const unsigned high_bit_depth = avctx->bits_per_raw_sample > 8;
28 
29  if (avctx->bits_per_raw_sample == 10 || avctx->bits_per_raw_sample == 9) {
30  c->fdct = ff_jpeg_fdct_islow_10;
31  c->fdct248 = ff_fdct248_islow_10;
32  } else if (avctx->dct_algo == FF_DCT_FASTINT) {
33  c->fdct = ff_fdct_ifast;
34  c->fdct248 = ff_fdct_ifast248;
35 #if CONFIG_FAANDCT
36  } else if (avctx->dct_algo == FF_DCT_FAAN) {
37  c->fdct = ff_faandct;
38  c->fdct248 = ff_faandct248;
39 #endif /* CONFIG_FAANDCT */
40  } else {
41  c->fdct = ff_jpeg_fdct_islow_8; // slow/accurate/default
42  c->fdct248 = ff_fdct248_islow_8;
43  }
44 
45 #if ARCH_AARCH64
46  ff_fdctdsp_init_aarch64(c, avctx, high_bit_depth);
47 #elif ARCH_PPC
48  ff_fdctdsp_init_ppc(c, avctx, high_bit_depth);
49 #elif ARCH_X86
50  ff_fdctdsp_init_x86(c, avctx, high_bit_depth);
51 #endif
52 }
FF_DCT_FAAN
#define FF_DCT_FAAN
Definition: avcodec.h:1540
av_unused
#define av_unused
Definition: attributes.h:131
ff_fdctdsp_init_x86
void ff_fdctdsp_init_x86(FDCTDSPContext *c, struct AVCodecContext *avctx, unsigned high_bit_depth)
Definition: fdctdsp_init.c:26
ff_fdctdsp_init_aarch64
av_cold void ff_fdctdsp_init_aarch64(FDCTDSPContext *c, AVCodecContext *avctx, unsigned high_bit_depth)
Definition: fdctdsp_init_aarch64.c:26
ff_fdct_ifast248
void ff_fdct_ifast248(int16_t *data)
Definition: jfdctfst.c:273
FDCTDSPContext
Definition: fdctdsp.h:28
faandct.h
Floating point AAN DCT.
AVCodecContext::dct_algo
int dct_algo
DCT algorithm, see FF_DCT_* below.
Definition: avcodec.h:1534
av_cold
#define av_cold
Definition: attributes.h:90
AVCodecContext::bits_per_raw_sample
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:1575
ff_fdctdsp_init_ppc
av_cold void ff_fdctdsp_init_ppc(FDCTDSPContext *c, AVCodecContext *avctx, unsigned high_bit_depth)
Definition: fdctdsp.c:465
ff_faandct
void ff_faandct(int16_t *data)
Definition: faandct.c:115
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
ff_fdct248_islow_8
void ff_fdct248_islow_8(int16_t *data)
attributes.h
ff_jpeg_fdct_islow_8
void ff_jpeg_fdct_islow_8(int16_t *data)
ff_fdctdsp_init
av_cold void ff_fdctdsp_init(FDCTDSPContext *c, AVCodecContext *avctx)
Definition: fdctdsp.c:25
ff_jpeg_fdct_islow_10
void ff_jpeg_fdct_islow_10(int16_t *data)
fdctdsp.h
FF_DCT_FASTINT
#define FF_DCT_FASTINT
Definition: avcodec.h:1536
avcodec.h
ff_fdct_ifast
void ff_fdct_ifast(int16_t *data)
Definition: jfdctfst.c:207
AVCodecContext
main external API structure.
Definition: avcodec.h:445
ff_fdct248_islow_10
void ff_fdct248_islow_10(int16_t *data)
ff_faandct248
void ff_faandct248(int16_t *data)
Definition: faandct.c:169