FFmpeg
mpegvideodsp.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 "libavutil/common.h"
22 #include "mpegvideodsp.h"
23 
24 static void gmc1_c(uint8_t *dst, const uint8_t *src, int stride, int h,
25  int x16, int y16, int rounder)
26 {
27  const int A = (16 - x16) * (16 - y16);
28  const int B = (x16) * (16 - y16);
29  const int C = (16 - x16) * (y16);
30  const int D = (x16) * (y16);
31  int i;
32 
33  for (i = 0; i < h; i++) {
34  dst[0] = (A * src[0] + B * src[1] + C * src[stride + 0] + D * src[stride + 1] + rounder) >> 8;
35  dst[1] = (A * src[1] + B * src[2] + C * src[stride + 1] + D * src[stride + 2] + rounder) >> 8;
36  dst[2] = (A * src[2] + B * src[3] + C * src[stride + 2] + D * src[stride + 3] + rounder) >> 8;
37  dst[3] = (A * src[3] + B * src[4] + C * src[stride + 3] + D * src[stride + 4] + rounder) >> 8;
38  dst[4] = (A * src[4] + B * src[5] + C * src[stride + 4] + D * src[stride + 5] + rounder) >> 8;
39  dst[5] = (A * src[5] + B * src[6] + C * src[stride + 5] + D * src[stride + 6] + rounder) >> 8;
40  dst[6] = (A * src[6] + B * src[7] + C * src[stride + 6] + D * src[stride + 7] + rounder) >> 8;
41  dst[7] = (A * src[7] + B * src[8] + C * src[stride + 7] + D * src[stride + 8] + rounder) >> 8;
42  dst += stride;
43  src += stride;
44  }
45 }
46 
47 void ff_gmc_c(uint8_t *dst, const uint8_t *src, int stride, int h, int ox, int oy,
48  int dxx, int dxy, int dyx, int dyy, int shift, int r,
49  int width, int height)
50 {
51  int y, vx, vy;
52  const int s = 1 << shift;
53 
54  width--;
55  height--;
56 
57  for (y = 0; y < h; y++) {
58  int x;
59 
60  vx = ox;
61  vy = oy;
62  for (x = 0; x < 8; x++) { // FIXME: optimize
63  int index;
64  int src_x = vx >> 16;
65  int src_y = vy >> 16;
66  int frac_x = src_x & (s - 1);
67  int frac_y = src_y & (s - 1);
68 
69  src_x >>= shift;
70  src_y >>= shift;
71 
72  if ((unsigned) src_x < width) {
73  if ((unsigned) src_y < height) {
74  index = src_x + src_y * stride;
75  dst[y * stride + x] =
76  ((src[index] * (s - frac_x) +
77  src[index + 1] * frac_x) * (s - frac_y) +
78  (src[index + stride] * (s - frac_x) +
79  src[index + stride + 1] * frac_x) * frac_y +
80  r) >> (shift * 2);
81  } else {
82  index = src_x + av_clip(src_y, 0, height) * stride;
83  dst[y * stride + x] =
84  ((src[index] * (s - frac_x) +
85  src[index + 1] * frac_x) * s +
86  r) >> (shift * 2);
87  }
88  } else {
89  if ((unsigned) src_y < height) {
90  index = av_clip(src_x, 0, width) + src_y * stride;
91  dst[y * stride + x] =
92  ((src[index] * (s - frac_y) +
93  src[index + stride] * frac_y) * s +
94  r) >> (shift * 2);
95  } else {
96  index = av_clip(src_x, 0, width) +
97  av_clip(src_y, 0, height) * stride;
98  dst[y * stride + x] = src[index];
99  }
100  }
101 
102  vx += dxx;
103  vy += dyx;
104  }
105  ox += dxy;
106  oy += dyy;
107  }
108 }
109 
111 {
112  c->gmc1 = gmc1_c;
113  c->gmc = ff_gmc_c;
114 
115 #if ARCH_PPC
117 #elif ARCH_X86
119 #endif
120 }
A
#define A(x)
Definition: vpx_arith.h:28
av_clip
#define av_clip
Definition: common.h:95
r
const char * r
Definition: vf_curves.c:116
D
D(D(float, sse)
Definition: rematrix_init.c:29
MpegVideoDSPContext
Definition: mpegvideodsp.h:28
C
s EdgeDetect Foobar g libavfilter vf_edgedetect c libavfilter vf_foobar c edit libavfilter and add an entry for foobar following the pattern of the other filters edit libavfilter allfilters and add an entry for foobar following the pattern of the other filters configure make j< whatever > ffmpeg ffmpeg i you should get a foobar png with Lena edge detected That s your new playground is ready Some little details about what s going which in turn will define variables for the build system and the C
Definition: writing_filters.txt:58
av_cold
#define av_cold
Definition: attributes.h:90
ff_mpegvideodsp_init_x86
av_cold void ff_mpegvideodsp_init_x86(MpegVideoDSPContext *c)
Definition: mpegvideodsp.c:153
width
#define width
s
#define s(width, name)
Definition: cbs_vp9.c:256
B
#define B
Definition: huffyuv.h:42
ff_mpegvideodsp_init
av_cold void ff_mpegvideodsp_init(MpegVideoDSPContext *c)
Definition: mpegvideodsp.c:110
ff_gmc_c
void ff_gmc_c(uint8_t *dst, const uint8_t *src, int stride, int h, int ox, int oy, int dxx, int dxy, int dyx, int dyy, int shift, int r, int width, int height)
Definition: mpegvideodsp.c:47
index
int index
Definition: gxfenc.c:89
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
mpegvideodsp.h
shift
static int shift(int a, int b)
Definition: bonk.c:260
height
#define height
attributes.h
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
gmc1_c
static void gmc1_c(uint8_t *dst, const uint8_t *src, int stride, int h, int x16, int y16, int rounder)
Definition: mpegvideodsp.c:24
common.h
stride
#define stride
Definition: h264pred_template.c:537
ff_mpegvideodsp_init_ppc
av_cold void ff_mpegvideodsp_init_ppc(MpegVideoDSPContext *c)
Definition: mpegvideodsp.c:131
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
h
h
Definition: vp9dsp_template.c:2038