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 "lossless_videoencdsp.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
diff_bytes_c(uint8_t * dst,const uint8_t * src1,const uint8_t * src2,intptr_t w)28 static void diff_bytes_c(uint8_t *dst, const uint8_t *src1, const uint8_t *src2, intptr_t 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
sub_median_pred_c(uint8_t * dst,const uint8_t * src1,const uint8_t * src2,intptr_t w,int * left,int * left_top)56 static void sub_median_pred_c(uint8_t *dst, const uint8_t *src1,
57 const uint8_t *src2, intptr_t 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
sub_left_predict_c(uint8_t * dst,uint8_t * src,ptrdiff_t stride,ptrdiff_t width,int height)77 static void sub_left_predict_c(uint8_t *dst, uint8_t *src,
78 ptrdiff_t stride, ptrdiff_t width, int height)
79 {
80 int i, j;
81 uint8_t prev = 0x80; /* Set the initial value */
82 for (j = 0; j < height; j++) {
83 for (i = 0; i < width; i++) {
84 *dst++ = src[i] - prev;
85 prev = src[i];
86 }
87 src += stride;
88 }
89 }
90
ff_llvidencdsp_init(LLVidEncDSPContext * c)91 av_cold void ff_llvidencdsp_init(LLVidEncDSPContext *c)
92 {
93 c->diff_bytes = diff_bytes_c;
94 c->sub_median_pred = sub_median_pred_c;
95 c->sub_left_predict = sub_left_predict_c;
96
97 if (ARCH_X86)
98 ff_llvidencdsp_init_x86(c);
99 }
100