FFmpeg
swscale.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 "config.h"
20 #include "libavutil/attributes.h"
21 #include "libswscale/swscale.h"
23 #include "libavutil/arm/cpu.h"
24 
25 void ff_hscale_8_to_15_neon(SwsInternal *c, int16_t *dst, int dstW,
26  const uint8_t *src, const int16_t *filter,
27  const int32_t *filterPos, int filterSize);
28 
29 void ff_yuv2planeX_8_neon(const int16_t *filter, int filterSize,
30  const int16_t **src, uint8_t *dest, int dstW,
31  const uint8_t *dither, int offset);
32 
34 {
36 
37  if (have_neon(cpu_flags)) {
38  if (c->srcBpc == 8 && c->dstBpc <= 14 &&
39  (c->hLumFilterSize % 8) == 0 &&
40  (c->hChrFilterSize % 8) == 0)
41  {
42  c->hyScale = c->hcScale = ff_hscale_8_to_15_neon;
43  }
44  if (c->dstBpc == 8) {
45  c->yuv2planeX = ff_yuv2planeX_8_neon;
46  }
47  }
48 }
ff_yuv2planeX_8_neon
void ff_yuv2planeX_8_neon(const int16_t *filter, int filterSize, const int16_t **src, uint8_t *dest, int dstW, const uint8_t *dither, int offset)
filter
void(* filter)(uint8_t *src, int stride, int qscale)
Definition: h263dsp.c:29
av_get_cpu_flags
int av_get_cpu_flags(void)
Return the flags which specify extensions supported by the CPU.
Definition: cpu.c:109
cpu_flags
static atomic_int cpu_flags
Definition: cpu.c:56
av_cold
#define av_cold
Definition: attributes.h:90
ff_sws_init_swscale_arm
av_cold void ff_sws_init_swscale_arm(SwsInternal *c)
Definition: swscale.c:33
cpu.h
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
dst
uint8_t ptrdiff_t const uint8_t ptrdiff_t int intptr_t intptr_t int int16_t * dst
Definition: dsp.h:83
have_neon
#define have_neon(flags)
Definition: cpu.h:26
offset
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
Definition: writing_filters.txt:86
attributes.h
swscale_internal.h
ff_hscale_8_to_15_neon
void ff_hscale_8_to_15_neon(SwsInternal *c, int16_t *dst, int dstW, const uint8_t *src, const int16_t *filter, const int32_t *filterPos, int filterSize)
SwsInternal
Definition: swscale_internal.h:317
int32_t
int32_t
Definition: audioconvert.c:56
src
#define src
Definition: vp8dsp.c:248
swscale.h
dither
static const uint8_t dither[8][8]
Definition: vf_fspp.c:62