2 * This file is part of FFmpeg.
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.
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.
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
22 #include "libavutil/attributes.h"
23 #include "libavutil/avassert.h"
24 #include "libavutil/mem.h"
28 av_cold void ff_rl_init(RLTable *rl,
29 uint8_t static_store[2][2 * MAX_RUN + MAX_LEVEL + 3])
31 int8_t max_level[MAX_RUN + 1], max_run[MAX_LEVEL + 1];
32 uint8_t index_run[MAX_RUN + 1];
33 int last, run, level, start, end, i;
35 /* If rl->max_level[0] is set, this RLTable has already been initialized */
39 /* compute max_level[], max_run[] and index_run[] */
40 for (last = 0; last < 2; last++) {
49 memset(max_level, 0, MAX_RUN + 1);
50 memset(max_run, 0, MAX_LEVEL + 1);
51 memset(index_run, rl->n, MAX_RUN + 1);
52 for (i = start; i < end; i++) {
53 run = rl->table_run[i];
54 level = rl->table_level[i];
55 if (index_run[run] == rl->n)
57 if (level > max_level[run])
58 max_level[run] = level;
59 if (run > max_run[level])
62 rl->max_level[last] = static_store[last];
63 memcpy(rl->max_level[last], max_level, MAX_RUN + 1);
64 rl->max_run[last] = static_store[last] + MAX_RUN + 1;
65 memcpy(rl->max_run[last], max_run, MAX_LEVEL + 1);
66 rl->index_run[last] = static_store[last] + MAX_RUN + MAX_LEVEL + 2;
67 memcpy(rl->index_run[last], index_run, MAX_RUN + 1);
71 av_cold void ff_rl_init_vlc(RLTable *rl, unsigned static_size)
74 VLC_TYPE table[1500][2] = {{0}};
75 VLC vlc = { .table = table, .table_allocated = static_size };
76 av_assert0(static_size <= FF_ARRAY_ELEMS(table));
77 init_vlc(&vlc, 9, rl->n + 1, &rl->table_vlc[0][1], 4, 2, &rl->table_vlc[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC);
79 for (q = 0; q < 32; q++) {
81 int qadd = (q - 1) | 1;
90 for (i = 0; i < vlc.table_size; i++) {
91 int code = vlc.table[i][0];
92 int len = vlc.table[i][1];
95 if (len == 0) { // illegal code
98 } else if (len < 0) { // more bits needed
102 if (code == rl->n) { // esc
106 run = rl->table_run[code] + 1;
107 level = rl->table_level[code] * qmul + qadd;
108 if (code >= rl->last) run += 192;
111 rl->rl_vlc[q][i].len = len;
112 rl->rl_vlc[q][i].level = level;
113 rl->rl_vlc[q][i].run = run;