FFmpeg
videodsp_template.c
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1 /*
2  * Copyright (c) 2002-2012 Michael Niedermayer
3  * Copyright (C) 2012 Ronald S. Bultje
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "bit_depth_template.c"
24  ptrdiff_t buf_linesize,
25  ptrdiff_t src_linesize,
26  int block_w, int block_h,
27  int src_x, int src_y, int w, int h)
28 {
29  int x, y;
30  int start_y, start_x, end_y, end_x;
31 
32  if (!w || !h)
33  return;
34 
35  av_assert2(block_w * sizeof(pixel) <= FFABS(buf_linesize));
36 
37  if (src_y >= h) {
38  src -= src_y * src_linesize;
39  src += (h - 1) * src_linesize;
40  src_y = h - 1;
41  } else if (src_y <= -block_h) {
42  src -= src_y * src_linesize;
43  src += (1 - block_h) * src_linesize;
44  src_y = 1 - block_h;
45  }
46  if (src_x >= w) {
47  // The subtracted expression has an unsigned type and must thus not be negative
48  src -= (1 + src_x - w) * sizeof(pixel);
49  src_x = w - 1;
50  } else if (src_x <= -block_w) {
51  src += (1 - block_w - src_x) * sizeof(pixel);
52  src_x = 1 - block_w;
53  }
54 
55  start_y = FFMAX(0, -src_y);
56  start_x = FFMAX(0, -src_x);
57  end_y = FFMIN(block_h, h-src_y);
58  end_x = FFMIN(block_w, w-src_x);
59  av_assert2(start_y < end_y && block_h);
60  av_assert2(start_x < end_x && block_w);
61 
62  w = end_x - start_x;
63  src += start_y * src_linesize + start_x * sizeof(pixel);
64  buf += start_x * sizeof(pixel);
65 
66  // top
67  for (y = 0; y < start_y; y++) {
68  memcpy(buf, src, w * sizeof(pixel));
69  buf += buf_linesize;
70  }
71 
72  // copy existing part
73  for (; y < end_y; y++) {
74  memcpy(buf, src, w * sizeof(pixel));
75  src += src_linesize;
76  buf += buf_linesize;
77  }
78 
79  // bottom
80  src -= src_linesize;
81  for (; y < block_h; y++) {
82  memcpy(buf, src, w * sizeof(pixel));
83  buf += buf_linesize;
84  }
85 
86  buf -= block_h * buf_linesize + start_x * sizeof(pixel);
87  while (block_h--) {
88  pixel *bufp = (pixel *) buf;
89 
90  // left
91  for(x = 0; x < start_x; x++) {
92  bufp[x] = bufp[start_x];
93  }
94 
95  // right
96  for (x = end_x; x < block_w; x++) {
97  bufp[x] = bufp[end_x - 1];
98  }
99  buf += buf_linesize;
100  }
101 }
#define src
Definition: vp8dsp.c:254
void FUNC() ff_emulated_edge_mc(uint8_t *buf, const uint8_t *src, ptrdiff_t buf_linesize, ptrdiff_t src_linesize, int block_w, int block_h, int src_x, int src_y, int w, int h)
uint8_t
#define av_assert2(cond)
assert() equivalent, that does lie in speed critical code.
Definition: avassert.h:64
#define FUNC(a)
#define FFMAX(a, b)
Definition: common.h:94
#define FFMIN(a, b)
Definition: common.h:96
uint8_t w
Definition: llviddspenc.c:38
#define FFABS(a)
Absolute value, Note, INT_MIN / INT64_MIN result in undefined behavior as they are not representable ...
Definition: common.h:72
void * buf
Definition: avisynth_c.h:766
uint8_t pixel
Definition: tiny_ssim.c:42