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, 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, 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  if (ARCH_X86)
119 }
av_cold void ff_mpegvideodsp_init(MpegVideoDSPContext *c)
Definition: mpegvideodsp.c:110
static int shift(int a, int b)
Definition: sonic.c:82
void(* gmc1)(uint8_t *dst, uint8_t *src, int srcStride, int h, int x16, int y16, int rounder)
translational global motion compensation.
Definition: mpegvideodsp.h:32
static void gmc1_c(uint8_t *dst, uint8_t *src, int stride, int h, int x16, int y16, int rounder)
Definition: mpegvideodsp.c:24
#define src
Definition: vp8dsp.c:254
Macro definitions for various function/variable attributes.
uint8_t
#define av_cold
Definition: attributes.h:82
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(* gmc)(uint8_t *dst, 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)
global motion compensation.
Definition: mpegvideodsp.h:37
#define height
#define A(x)
Definition: vp56_arith.h:28
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define B
Definition: huffyuvdsp.h:32
const char * r
Definition: vf_curves.c:114
av_cold void ff_mpegvideodsp_init_x86(MpegVideoDSPContext *c)
Definition: mpegvideodsp.c:153
void ff_gmc_c(uint8_t *dst, 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
#define width
#define s(width, name)
Definition: cbs_vp9.c:257
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
int index
Definition: gxfenc.c:89
GLint GLenum GLboolean GLsizei stride
Definition: opengl_enc.c:104
common internal and external API header
D(D(float, sse)
Definition: rematrix_init.c:28
av_cold void ff_mpegvideodsp_init_ppc(MpegVideoDSPContext *c)
Definition: mpegvideodsp.c:130
#define stride