3
* Common code for Vorbis I encoder and decoder
4
* @author Denes Balatoni ( dbalatoni programozo hu )
6
* This file is part of FFmpeg.
8
* FFmpeg is free software; you can redistribute it and/or
9
* modify it under the terms of the GNU Lesser General Public
10
* License as published by the Free Software Foundation; either
11
* version 2.1 of the License, or (at your option) any later version.
13
* FFmpeg is distributed in the hope that it will be useful,
14
* but WITHOUT ANY WARRANTY; without even the implied warranty of
15
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16
* Lesser General Public License for more details.
18
* You should have received a copy of the GNU Lesser General Public
19
* License along with FFmpeg; if not, write to the Free Software
20
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26
#define ALT_BITSTREAM_READER_LE
33
/* Helper functions */
36
unsigned int ff_vorbis_nth_root(unsigned int x, unsigned int n)
38
unsigned int ret = 0, i, j;
42
for (i = 0, j = ret; i < n - 1; i++)
49
// Generate vlc codes from vorbis huffman code lengths
51
// the two bits[p] > 32 checks should be redundant, all calling code should
52
// already ensure that, but since it allows overwriting the stack it seems
53
// reasonable to check redundantly.
54
int ff_vorbis_len2vlc(uint8_t *bits, uint32_t *codes, uint_fast32_t num)
56
uint_fast32_t exit_at_level[33] = {
57
404, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
58
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
61
uint_fast32_t code, p;
67
for (p = 0; (bits[p] == 0) && (p < num); ++p)
70
// av_log(vc->avccontext, AV_LOG_INFO, "An empty codebook. Heh?! \n");
77
for (i = 0; i < bits[p]; ++i)
78
exit_at_level[i+1] = 1 << i;
81
av_log(NULL, AV_LOG_INFO, " %d. of %d code len %d code %d - ", p, num, bits[p], codes[p]);
82
init_get_bits(&gb, (uint_fast8_t *)&codes[p], bits[p]);
83
for (i = 0; i < bits[p]; ++i)
84
av_log(NULL, AV_LOG_INFO, "%s", get_bits1(&gb) ? "1" : "0");
85
av_log(NULL, AV_LOG_INFO, "\n");
90
for (; p < num; ++p) {
95
// find corresponding exit(node which the tree can grow further from)
96
for (i = bits[p]; i > 0; --i)
99
if (!i) // overspecified tree
101
code = exit_at_level[i];
102
exit_at_level[i] = 0;
103
// construct code (append 0s to end) and introduce new exits
104
for (j = i + 1 ;j <= bits[p]; ++j)
105
exit_at_level[j] = code + (1 << (j - 1));
109
av_log(NULL, AV_LOG_INFO, " %d. code len %d code %d - ", p, bits[p], codes[p]);
110
init_get_bits(&gb, (uint_fast8_t *)&codes[p], bits[p]);
111
for (i = 0; i < bits[p]; ++i)
112
av_log(NULL, AV_LOG_INFO, "%s", get_bits1(&gb) ? "1" : "0");
113
av_log(NULL, AV_LOG_INFO, "\n");
118
//no exits should be left (underspecified tree - ie. unused valid vlcs - not allowed by SPEC)
119
for (p = 1; p < 33; p++)
120
if (exit_at_level[p])
126
void ff_vorbis_ready_floor1_list(vorbis_floor1_entry * list, int values)
131
for (i = 2; i < values; i++) {
136
for (j = 2; j < i; j++) {
138
if (tmp < list[i].x) {
139
if (tmp > list[list[i].low].x)
142
if (tmp < list[list[i].high].x)
147
for (i = 0; i < values - 1; i++) {
149
for (j = i + 1; j < values; j++) {
150
if (list[list[i].sort].x > list[list[j].sort].x) {
151
int tmp = list[i].sort;
152
list[i].sort = list[j].sort;
159
static inline void render_line_unrolled(intptr_t x, intptr_t y, int x1,
160
intptr_t sy, int ady, int adx,
171
buf[x++] = ff_vorbis_floor1_inverse_db_table[y];
173
buf[x] = ff_vorbis_floor1_inverse_db_table[y];
178
buf[x] = ff_vorbis_floor1_inverse_db_table[y];
182
static void render_line(int x0, int y0, int x1, int y1, float *buf)
187
int sy = dy < 0 ? -1 : 1;
188
buf[x0] = ff_vorbis_floor1_inverse_db_table[y0];
189
if (ady*2 <= adx) { // optimized common case
190
render_line_unrolled(x0, y0, x1, sy, ady, adx, buf);
196
ady -= FFABS(base) * adx;
204
buf[x] = ff_vorbis_floor1_inverse_db_table[y];
209
void ff_vorbis_floor1_render_list(vorbis_floor1_entry * list, int values,
210
uint_fast16_t *y_list, int *flag,
211
int multiplier, float *out, int samples)
215
ly = y_list[0] * multiplier;
216
for (i = 1; i < values; i++) {
217
int pos = list[i].sort;
219
int x1 = list[pos].x;
220
int y1 = y_list[pos] * multiplier;
222
render_line(lx, ly, FFMIN(x1,samples), y1, out);
230
render_line(lx, ly, samples, ly, out);