9cdf82c2c2
Therefore use a proper prefix for this API, e.g. ff_init_vlc_sparse -> ff_vlc_init_sparse ff_free_vlc -> ff_vlc_free INIT_VLC_LE -> VLC_INIT_LE INIT_VLC_USE_NEW_STATIC -> VLC_INIT_USE_STATIC (The ancient INIT_VLC_USE_STATIC has been removed in 595324e143b57a52e2329eb47b84395c70f93087, so that the NEW has been dropped.) Finally, reorder the flags and change their values accordingly. Reviewed-by: Michael Niedermayer <michael@niedermayer.cc> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
58 lines
1.8 KiB
C
58 lines
1.8 KiB
C
/*
|
|
* MJPEG decoder VLC code
|
|
* Copyright (c) 2000, 2001 Fabrice Bellard
|
|
* Copyright (c) 2003 Alex Beregszaszi
|
|
* Copyright (c) 2003-2004 Michael Niedermayer
|
|
*
|
|
* 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
|
|
*/
|
|
|
|
#include <stdint.h>
|
|
#include "libavutil/avassert.h"
|
|
#include "mjpegdec.h"
|
|
#include "vlc.h"
|
|
|
|
static int build_huffman_codes(uint8_t *huff_size, const uint8_t *bits_table)
|
|
{
|
|
int nb_codes = 0;
|
|
for (int i = 1, j = 0; i <= 16; i++) {
|
|
nb_codes += bits_table[i];
|
|
av_assert1(nb_codes <= 256);
|
|
for (; j < nb_codes; j++)
|
|
huff_size[j] = i;
|
|
}
|
|
return nb_codes;
|
|
}
|
|
|
|
int ff_mjpeg_build_vlc(VLC *vlc, const uint8_t *bits_table,
|
|
const uint8_t *val_table, int is_ac, void *logctx)
|
|
{
|
|
uint8_t huff_size[256];
|
|
uint16_t huff_sym[256];
|
|
int nb_codes = build_huffman_codes(huff_size, bits_table);
|
|
|
|
for (int i = 0; i < nb_codes; i++) {
|
|
huff_sym[i] = val_table[i] + 16 * is_ac;
|
|
|
|
if (is_ac && !val_table[i])
|
|
huff_sym[i] = 16 * 256;
|
|
}
|
|
|
|
return ff_vlc_init_from_lengths(vlc, 9, nb_codes, huff_size, 1,
|
|
huff_sym, 2, 2, 0, 0, logctx);
|
|
}
|