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FFmpeg/libavcodec/dv_tablegen.h
Andreas Rheinhardt 116e2a9ee2 avcodec/dv_tablegen, dvdata: Remove ff_dv_vlc_bits
The codes can be easily calculated, so the table is unnecessary.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-09-07 00:07:45 +02:00

102 lines
3.4 KiB
C

/*
* Header file for hardcoded DV tables
*
* Copyright (c) 2010 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef AVCODEC_DV_TABLEGEN_H
#define AVCODEC_DV_TABLEGEN_H
#include <stdint.h>
#include "libavutil/attributes.h"
#include "dvdata.h"
#if CONFIG_SMALL
#define DV_VLC_MAP_RUN_SIZE 15
#define DV_VLC_MAP_LEV_SIZE 23
#else
#define DV_VLC_MAP_RUN_SIZE 64
#define DV_VLC_MAP_LEV_SIZE 512 // FIXME sign was removed so this should be /2 but needs check
#endif
/* VLC encoding lookup table */
typedef struct dv_vlc_pair {
uint32_t vlc;
uint32_t size;
} dv_vlc_pair;
#if CONFIG_HARDCODED_TABLES
#define dv_vlc_map_tableinit()
#include "libavcodec/dv_tables.h"
#else
static struct dv_vlc_pair dv_vlc_map[DV_VLC_MAP_RUN_SIZE][DV_VLC_MAP_LEV_SIZE];
static av_cold void dv_vlc_map_tableinit(void)
{
uint32_t code = 0;
int i, j;
for (int i = 0; i < NB_DV_VLC; i++) {
uint32_t cur_code = code >> (32 - ff_dv_vlc_len[i]);
code += 1U << (32 - ff_dv_vlc_len[i]);
if (ff_dv_vlc_run[i] >= DV_VLC_MAP_RUN_SIZE)
continue;
#if CONFIG_SMALL
if (ff_dv_vlc_level[i] >= DV_VLC_MAP_LEV_SIZE)
continue;
#endif
if (dv_vlc_map[ff_dv_vlc_run[i]][ff_dv_vlc_level[i]].size != 0)
continue;
dv_vlc_map[ff_dv_vlc_run[i]][ff_dv_vlc_level[i]].vlc =
cur_code << (!!ff_dv_vlc_level[i]);
dv_vlc_map[ff_dv_vlc_run[i]][ff_dv_vlc_level[i]].size =
ff_dv_vlc_len[i] + (!!ff_dv_vlc_level[i]);
}
for (i = 0; i < DV_VLC_MAP_RUN_SIZE; i++) {
#if CONFIG_SMALL
for (j = 1; j < DV_VLC_MAP_LEV_SIZE; j++) {
if (dv_vlc_map[i][j].size == 0) {
dv_vlc_map[i][j].vlc = dv_vlc_map[0][j].vlc |
(dv_vlc_map[i - 1][0].vlc <<
dv_vlc_map[0][j].size);
dv_vlc_map[i][j].size = dv_vlc_map[i - 1][0].size +
dv_vlc_map[0][j].size;
}
}
#else
for (j = 1; j < DV_VLC_MAP_LEV_SIZE / 2; j++) {
if (dv_vlc_map[i][j].size == 0) {
dv_vlc_map[i][j].vlc = dv_vlc_map[0][j].vlc |
(dv_vlc_map[i - 1][0].vlc <<
dv_vlc_map[0][j].size);
dv_vlc_map[i][j].size = dv_vlc_map[i - 1][0].size +
dv_vlc_map[0][j].size;
}
dv_vlc_map[i][((uint16_t) (-j)) & 0x1ff].vlc = dv_vlc_map[i][j].vlc | 1;
dv_vlc_map[i][((uint16_t) (-j)) & 0x1ff].size = dv_vlc_map[i][j].size;
}
#endif
}
}
#endif /* CONFIG_HARDCODED_TABLES */
#endif /* AVCODEC_DV_TABLEGEN_H */