ffmpeg/libavcodec/mpeg4audio_copy_pce.h

70 lines
2.5 KiB
C

/*
* MPEG-4 Audio PCE copying function
*
* 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_MPEG4AUDIO_COPY_PCE_H
#define AVCODEC_MPEG4AUDIO_COPY_PCE_H
#include "libavutil/attributes.h"
#include "get_bits.h"
#include "put_bits.h"
static av_always_inline unsigned int ff_pce_copy_bits(PutBitContext *pb,
GetBitContext *gb,
int bits)
{
unsigned int el = get_bits(gb, bits);
put_bits(pb, bits, el);
return el;
}
static inline int ff_copy_pce_data(PutBitContext *pb, GetBitContext *gb)
{
int five_bit_ch, four_bit_ch, comment_size, bits;
int offset = put_bits_count(pb);
ff_pce_copy_bits(pb, gb, 10); // Tag, Object Type, Frequency
five_bit_ch = ff_pce_copy_bits(pb, gb, 4); // Front
five_bit_ch += ff_pce_copy_bits(pb, gb, 4); // Side
five_bit_ch += ff_pce_copy_bits(pb, gb, 4); // Back
four_bit_ch = ff_pce_copy_bits(pb, gb, 2); // LFE
four_bit_ch += ff_pce_copy_bits(pb, gb, 3); // Data
five_bit_ch += ff_pce_copy_bits(pb, gb, 4); // Coupling
if (ff_pce_copy_bits(pb, gb, 1)) // Mono Mixdown
ff_pce_copy_bits(pb, gb, 4);
if (ff_pce_copy_bits(pb, gb, 1)) // Stereo Mixdown
ff_pce_copy_bits(pb, gb, 4);
if (ff_pce_copy_bits(pb, gb, 1)) // Matrix Mixdown
ff_pce_copy_bits(pb, gb, 3);
for (bits = five_bit_ch*5+four_bit_ch*4; bits > 16; bits -= 16)
ff_pce_copy_bits(pb, gb, 16);
if (bits)
ff_pce_copy_bits(pb, gb, bits);
align_put_bits(pb);
align_get_bits(gb);
comment_size = ff_pce_copy_bits(pb, gb, 8);
for (; comment_size > 0; comment_size--)
ff_pce_copy_bits(pb, gb, 8);
return put_bits_count(pb) - offset;
}
#endif /* AVCODEC_MPEG4AUDIO_COPY_PCE_H */