1/*
2 *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
3 *
4 *  Use of this source code is governed by a BSD-style license
5 *  that can be found in the LICENSE file in the root of the source
6 *  tree. An additional intellectual property rights grant can be found
7 *  in the file PATENTS.  All contributing project authors may
8 *  be found in the AUTHORS file in the root of the source tree.
9 */
10
11#include <math.h>
12
13#include "./vp8_rtcd.h"
14
15void vp8_short_fdct4x4_c(short *input, short *output, int pitch) {
16  int i;
17  int a1, b1, c1, d1;
18  short *ip = input;
19  short *op = output;
20
21  for (i = 0; i < 4; ++i) {
22    a1 = ((ip[0] + ip[3]) * 8);
23    b1 = ((ip[1] + ip[2]) * 8);
24    c1 = ((ip[1] - ip[2]) * 8);
25    d1 = ((ip[0] - ip[3]) * 8);
26
27    op[0] = a1 + b1;
28    op[2] = a1 - b1;
29
30    op[1] = (c1 * 2217 + d1 * 5352 + 14500) >> 12;
31    op[3] = (d1 * 2217 - c1 * 5352 + 7500) >> 12;
32
33    ip += pitch / 2;
34    op += 4;
35  }
36  ip = output;
37  op = output;
38  for (i = 0; i < 4; ++i) {
39    a1 = ip[0] + ip[12];
40    b1 = ip[4] + ip[8];
41    c1 = ip[4] - ip[8];
42    d1 = ip[0] - ip[12];
43
44    op[0] = (a1 + b1 + 7) >> 4;
45    op[8] = (a1 - b1 + 7) >> 4;
46
47    op[4] = ((c1 * 2217 + d1 * 5352 + 12000) >> 16) + (d1 != 0);
48    op[12] = (d1 * 2217 - c1 * 5352 + 51000) >> 16;
49
50    ip++;
51    op++;
52  }
53}
54
55void vp8_short_fdct8x4_c(short *input, short *output, int pitch) {
56  vp8_short_fdct4x4_c(input, output, pitch);
57  vp8_short_fdct4x4_c(input + 4, output + 16, pitch);
58}
59
60void vp8_short_walsh4x4_c(short *input, short *output, int pitch) {
61  int i;
62  int a1, b1, c1, d1;
63  int a2, b2, c2, d2;
64  short *ip = input;
65  short *op = output;
66
67  for (i = 0; i < 4; ++i) {
68    a1 = ((ip[0] + ip[2]) * 4);
69    d1 = ((ip[1] + ip[3]) * 4);
70    c1 = ((ip[1] - ip[3]) * 4);
71    b1 = ((ip[0] - ip[2]) * 4);
72
73    op[0] = a1 + d1 + (a1 != 0);
74    op[1] = b1 + c1;
75    op[2] = b1 - c1;
76    op[3] = a1 - d1;
77    ip += pitch / 2;
78    op += 4;
79  }
80
81  ip = output;
82  op = output;
83
84  for (i = 0; i < 4; ++i) {
85    a1 = ip[0] + ip[8];
86    d1 = ip[4] + ip[12];
87    c1 = ip[4] - ip[12];
88    b1 = ip[0] - ip[8];
89
90    a2 = a1 + d1;
91    b2 = b1 + c1;
92    c2 = b1 - c1;
93    d2 = a1 - d1;
94
95    a2 += a2 < 0;
96    b2 += b2 < 0;
97    c2 += c2 < 0;
98    d2 += d2 < 0;
99
100    op[0] = (a2 + 3) >> 3;
101    op[4] = (b2 + 3) >> 3;
102    op[8] = (c2 + 3) >> 3;
103    op[12] = (d2 + 3) >> 3;
104
105    ip++;
106    op++;
107  }
108}
109