1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
|
/*
* Copyright (c) 2016, Alliance for Open Media. All rights reserved
*
* This source code is subject to the terms of the BSD 2 Clause License and
* the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
* was not distributed with this source code in the LICENSE file, you can
* obtain it at www.aomedia.org/license/software. If the Alliance for Open
* Media Patent License 1.0 was not distributed with this source code in the
* PATENTS file, you can obtain it at www.aomedia.org/license/patent.
*/
#include <assert.h>
#include "aom_dsp/txfm_common.h"
#include "config/aom_dsp_rtcd.h"
void aom_fdct4x4_c(const int16_t *input, tran_low_t *output, int stride) {
// The 2D transform is done with two passes which are actually pretty
// similar. In the first one, we transform the columns and transpose
// the results. In the second one, we transform the rows. To achieve that,
// as the first pass results are transposed, we transpose the columns (that
// is the transposed rows) and transpose the results (so that it goes back
// in normal/row positions).
// We need an intermediate buffer between passes.
tran_low_t intermediate[4 * 4];
const tran_low_t *in_low = NULL;
tran_low_t *out = intermediate;
// Do the two transform/transpose passes
for (int pass = 0; pass < 2; ++pass) {
tran_high_t in_high[4]; // canbe16
tran_high_t step[4]; // canbe16
tran_high_t temp1, temp2; // needs32
for (int i = 0; i < 4; ++i) {
// Load inputs.
if (pass == 0) {
in_high[0] = input[0 * stride] * 16;
in_high[1] = input[1 * stride] * 16;
in_high[2] = input[2 * stride] * 16;
in_high[3] = input[3 * stride] * 16;
if (i == 0 && in_high[0]) {
++in_high[0];
}
} else {
assert(in_low != NULL);
in_high[0] = in_low[0 * 4];
in_high[1] = in_low[1 * 4];
in_high[2] = in_low[2 * 4];
in_high[3] = in_low[3 * 4];
++in_low;
}
// Transform.
step[0] = in_high[0] + in_high[3];
step[1] = in_high[1] + in_high[2];
step[2] = in_high[1] - in_high[2];
step[3] = in_high[0] - in_high[3];
temp1 = (step[0] + step[1]) * cospi_16_64;
temp2 = (step[0] - step[1]) * cospi_16_64;
out[0] = (tran_low_t)fdct_round_shift(temp1);
out[2] = (tran_low_t)fdct_round_shift(temp2);
temp1 = step[2] * cospi_24_64 + step[3] * cospi_8_64;
temp2 = -step[2] * cospi_8_64 + step[3] * cospi_24_64;
out[1] = (tran_low_t)fdct_round_shift(temp1);
out[3] = (tran_low_t)fdct_round_shift(temp2);
// Do next column (which is a transposed row in second/horizontal pass)
++input;
out += 4;
}
// Setup in/out for next pass.
in_low = intermediate;
out = output;
}
for (int i = 0; i < 4; ++i) {
for (int j = 0; j < 4; ++j)
output[j + i * 4] = (output[j + i * 4] + 1) >> 2;
}
}
void aom_fdct4x4_lp_c(const int16_t *input, int16_t *output, int stride) {
// The 2D transform is done with two passes which are actually pretty
// similar. In the first one, we transform the columns and transpose
// the results. In the second one, we transform the rows. To achieve that,
// as the first pass results are transposed, we transpose the columns (that
// is the transposed rows) and transpose the results (so that it goes back
// in normal/row positions).
// We need an intermediate buffer between passes.
int16_t intermediate[4 * 4];
const int16_t *in_low = NULL;
int16_t *out = intermediate;
// Do the two transform/transpose passes
for (int pass = 0; pass < 2; ++pass) {
int32_t in_high[4]; // canbe16
int32_t step[4]; // canbe16
int32_t temp1, temp2; // needs32
for (int i = 0; i < 4; ++i) {
// Load inputs.
if (pass == 0) {
in_high[0] = input[0 * stride] * 16;
in_high[1] = input[1 * stride] * 16;
in_high[2] = input[2 * stride] * 16;
in_high[3] = input[3 * stride] * 16;
if (i == 0 && in_high[0]) {
++in_high[0];
}
} else {
assert(in_low != NULL);
in_high[0] = in_low[0 * 4];
in_high[1] = in_low[1 * 4];
in_high[2] = in_low[2 * 4];
in_high[3] = in_low[3 * 4];
++in_low;
}
// Transform.
step[0] = in_high[0] + in_high[3];
step[1] = in_high[1] + in_high[2];
step[2] = in_high[1] - in_high[2];
step[3] = in_high[0] - in_high[3];
temp1 = (step[0] + step[1]) * (int32_t)cospi_16_64;
temp2 = (step[0] - step[1]) * (int32_t)cospi_16_64;
out[0] = (int16_t)fdct_round_shift(temp1);
out[2] = (int16_t)fdct_round_shift(temp2);
temp1 = step[2] * (int32_t)cospi_24_64 + step[3] * (int32_t)cospi_8_64;
temp2 = -step[2] * (int32_t)cospi_8_64 + step[3] * (int32_t)cospi_24_64;
out[1] = (int16_t)fdct_round_shift(temp1);
out[3] = (int16_t)fdct_round_shift(temp2);
// Do next column (which is a transposed row in second/horizontal pass)
++input;
out += 4;
}
// Setup in/out for next pass.
in_low = intermediate;
out = output;
}
for (int i = 0; i < 4; ++i) {
for (int j = 0; j < 4; ++j)
output[j + i * 4] = (output[j + i * 4] + 1) >> 2;
}
}
void aom_fdct8x8_c(const int16_t *input, tran_low_t *final_output, int stride) {
int i, j;
tran_low_t intermediate[64];
int pass;
tran_low_t *output = intermediate;
const tran_low_t *in = NULL;
// Transform columns
for (pass = 0; pass < 2; ++pass) {
tran_high_t s0, s1, s2, s3, s4, s5, s6, s7; // canbe16
tran_high_t t0, t1, t2, t3; // needs32
tran_high_t x0, x1, x2, x3; // canbe16
for (i = 0; i < 8; i++) {
// stage 1
if (pass == 0) {
s0 = (input[0 * stride] + input[7 * stride]) * 4;
s1 = (input[1 * stride] + input[6 * stride]) * 4;
s2 = (input[2 * stride] + input[5 * stride]) * 4;
s3 = (input[3 * stride] + input[4 * stride]) * 4;
s4 = (input[3 * stride] - input[4 * stride]) * 4;
s5 = (input[2 * stride] - input[5 * stride]) * 4;
s6 = (input[1 * stride] - input[6 * stride]) * 4;
s7 = (input[0 * stride] - input[7 * stride]) * 4;
++input;
} else {
s0 = in[0 * 8] + in[7 * 8];
s1 = in[1 * 8] + in[6 * 8];
s2 = in[2 * 8] + in[5 * 8];
s3 = in[3 * 8] + in[4 * 8];
s4 = in[3 * 8] - in[4 * 8];
s5 = in[2 * 8] - in[5 * 8];
s6 = in[1 * 8] - in[6 * 8];
s7 = in[0 * 8] - in[7 * 8];
++in;
}
// fdct4(step, step);
x0 = s0 + s3;
x1 = s1 + s2;
x2 = s1 - s2;
x3 = s0 - s3;
t0 = (x0 + x1) * cospi_16_64;
t1 = (x0 - x1) * cospi_16_64;
t2 = x2 * cospi_24_64 + x3 * cospi_8_64;
t3 = -x2 * cospi_8_64 + x3 * cospi_24_64;
output[0] = (tran_low_t)fdct_round_shift(t0);
output[2] = (tran_low_t)fdct_round_shift(t2);
output[4] = (tran_low_t)fdct_round_shift(t1);
output[6] = (tran_low_t)fdct_round_shift(t3);
// Stage 2
t0 = (s6 - s5) * cospi_16_64;
t1 = (s6 + s5) * cospi_16_64;
t2 = fdct_round_shift(t0);
t3 = fdct_round_shift(t1);
// Stage 3
x0 = s4 + t2;
x1 = s4 - t2;
x2 = s7 - t3;
x3 = s7 + t3;
// Stage 4
t0 = x0 * cospi_28_64 + x3 * cospi_4_64;
t1 = x1 * cospi_12_64 + x2 * cospi_20_64;
t2 = x2 * cospi_12_64 + x1 * -cospi_20_64;
t3 = x3 * cospi_28_64 + x0 * -cospi_4_64;
output[1] = (tran_low_t)fdct_round_shift(t0);
output[3] = (tran_low_t)fdct_round_shift(t2);
output[5] = (tran_low_t)fdct_round_shift(t1);
output[7] = (tran_low_t)fdct_round_shift(t3);
output += 8;
}
in = intermediate;
output = final_output;
}
// Rows
for (i = 0; i < 8; ++i) {
for (j = 0; j < 8; ++j) final_output[j + i * 8] /= 2;
}
}
#if CONFIG_AV1_HIGHBITDEPTH
void aom_highbd_fdct8x8_c(const int16_t *input, tran_low_t *final_output,
int stride) {
aom_fdct8x8_c(input, final_output, stride);
}
#endif
|
