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huffyuvencdsp.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 "huffyuvencdsp.h"
22 #include "mathops.h"
23 
24 // 0x7f7f7f7f or 0x7f7f7f7f7f7f7f7f or whatever, depending on the cpu's native arithmetic size
25 #define pb_7f (~0UL / 255 * 0x7f)
26 #define pb_80 (~0UL / 255 * 0x80)
27 
28 static void diff_bytes_c(uint8_t *dst, const uint8_t *src1, const uint8_t *src2, int w)
29 {
30  long i;
31 
32 #if !HAVE_FAST_UNALIGNED
33  if (((long)src1 | (long)src2) & (sizeof(long) - 1)) {
34  for (i = 0; i + 7 < w; i += 8) {
35  dst[i + 0] = src1[i + 0] - src2[i + 0];
36  dst[i + 1] = src1[i + 1] - src2[i + 1];
37  dst[i + 2] = src1[i + 2] - src2[i + 2];
38  dst[i + 3] = src1[i + 3] - src2[i + 3];
39  dst[i + 4] = src1[i + 4] - src2[i + 4];
40  dst[i + 5] = src1[i + 5] - src2[i + 5];
41  dst[i + 6] = src1[i + 6] - src2[i + 6];
42  dst[i + 7] = src1[i + 7] - src2[i + 7];
43  }
44  } else
45 #endif
46  for (i = 0; i <= w - (int) sizeof(long); i += sizeof(long)) {
47  long a = *(long *) (src1 + i);
48  long b = *(long *) (src2 + i);
49  *(long *) (dst + i) = ((a | pb_80) - (b & pb_7f)) ^
50  ((a ^ b ^ pb_80) & pb_80);
51  }
52  for (; i < w; i++)
53  dst[i + 0] = src1[i + 0] - src2[i + 0];
54 }
55 
56 static void sub_hfyu_median_pred_c(uint8_t *dst, const uint8_t *src1,
57  const uint8_t *src2, int w,
58  int *left, int *left_top)
59 {
60  int i;
61  uint8_t l, lt;
62 
63  l = *left;
64  lt = *left_top;
65 
66  for (i = 0; i < w; i++) {
67  const int pred = mid_pred(l, src1[i], (l + src1[i] - lt) & 0xFF);
68  lt = src1[i];
69  l = src2[i];
70  dst[i] = l - pred;
71  }
72 
73  *left = l;
74  *left_top = lt;
75 }
76 
78 {
81 
82  if (ARCH_X86)
84 }