mirror of
https://gitee.com/openharmony/third_party_ffmpeg
synced 2024-11-24 19:59:46 +00:00
08a747afb9
This checks if the set of selected exponent strategies for all blocks in a channel are in the frame exponent strategy table, and if so, writes the table index instead of each strategy. This saves up to 7 bits per channel per frame, so the overall effect on quality is small.
55 lines
1.5 KiB
C
55 lines
1.5 KiB
C
/*
|
|
* E-AC-3 encoder
|
|
* Copyright (c) 2011 Justin Ruggles <justin.ruggles@gmail.com>
|
|
*
|
|
* This file is part of Libav.
|
|
*
|
|
* Libav 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.
|
|
*
|
|
* Libav 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 Libav; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
/**
|
|
* @file
|
|
* E-AC-3 encoder
|
|
*/
|
|
|
|
#ifndef AVCODEC_EAC3ENC_H
|
|
#define AVCODEC_EAC3ENC_H
|
|
|
|
#include "ac3enc.h"
|
|
|
|
/**
|
|
* Initialize E-AC-3 exponent tables.
|
|
*/
|
|
void ff_eac3_exponent_init(void);
|
|
|
|
/**
|
|
* Determine frame exponent strategy use and indices.
|
|
*/
|
|
void ff_eac3_get_frame_exp_strategy(AC3EncodeContext *s);
|
|
|
|
/**
|
|
* Set coupling states.
|
|
* This determines whether certain flags must be written to the bitstream or
|
|
* whether they will be implicitly already known by the decoder.
|
|
*/
|
|
void ff_eac3_set_cpl_states(AC3EncodeContext *s);
|
|
|
|
/**
|
|
* Write the E-AC-3 frame header to the output bitstream.
|
|
*/
|
|
void ff_eac3_output_frame_header(AC3EncodeContext *s);
|
|
|
|
#endif /* AVCODEC_EAC3ENC_H */
|