Go to the documentation of this file.
1 /*
2  * ARM-NEON-optimized IDCT functions
3  * Copyright (c) 2008 Mans Rullgard <mans@mansr.com>
4  * Copyright (c) 2017 Matthieu Bouron <matthieu.bouron@gmail.com>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
23 #include "libavutil/attributes.h"
24 #include "libavutil/cpu.h"
25 #include "libavutil/arm/cpu.h"
26 #include "libavcodec/avcodec.h"
27 #include "libavcodec/idctdsp.h"
28 #include "idct.h"
31  unsigned high_bit_depth)
32 {
35  if (have_neon(cpu_flags) && !avctx->lowres && !high_bit_depth) {
36  if (avctx->idct_algo == FF_IDCT_AUTO ||
37  avctx->idct_algo == FF_IDCT_SIMPLEAUTO ||
38  avctx->idct_algo == FF_IDCT_SIMPLENEON) {
43  }
44  }
45 }
void ff_simple_idct_add_neon(uint8_t *dest, ptrdiff_t line_size, int16_t *data)
static atomic_int cpu_flags
Definition: cpu.c:50
Macro definitions for various function/variable attributes.
#define av_cold
Definition: attributes.h:88
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
void ff_simple_idct_neon(int16_t *data)
int lowres
low resolution decoding, 1-> 1/2 size, 2->1/4 size
Definition: avcodec.h:1749
void ff_simple_idct_put_neon(uint8_t *dest, ptrdiff_t line_size, int16_t *data)
#define FF_IDCT_AUTO
Definition: avcodec.h:1715
Definition: avcodec.h:1728
#define have_neon(flags)
Definition: cpu.h:26
int idct_algo
IDCT algorithm, see FF_IDCT_* below.
Definition: avcodec.h:1714
void(* idct_add)(uint8_t *dest, ptrdiff_t line_size, int16_t *block)
block -> idct -> add dest -> clip to unsigned 8 bit -> dest.
Definition: idctdsp.h:79
void(* idct_put)(uint8_t *dest, ptrdiff_t line_size, int16_t *block)
block -> idct -> clip to unsigned 8 bit -> dest.
Definition: idctdsp.h:72
Libavcodec external API header.
Definition: avcodec.h:1726
main external API structure.
Definition: avcodec.h:531
int av_get_cpu_flags(void)
Return the flags which specify extensions supported by the CPU.
Definition: cpu.c:95
av_cold void ff_idctdsp_init_aarch64(IDCTDSPContext *c, AVCodecContext *avctx, unsigned high_bit_depth)
void(* idct)(int16_t *block)
Definition: idctdsp.h:65
enum idct_permutation_type perm_type
Definition: idctdsp.h:97