RepoMirrors
/
ffmpeg
mirror of https://git.ffmpeg.org/ffmpeg.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
ffmpeg/libavcodec/wma.h

160 lines
6.2 KiB
C
Raw Blame History

/*
* WMA compatible codec
* Copyright (c) 2002-2007 The Libav Project
*
* 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
*/
#ifndef AVCODEC_WMA_H
#define AVCODEC_WMA_H
#include "libavutil/float_dsp.h"
#include "get_bits.h"
#include "put_bits.h"
#include "fft.h"
#include "fmtconvert.h"
/* size of blocks */
#define BLOCK_MIN_BITS 7
#define BLOCK_MAX_BITS 11
#define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
#define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
/* XXX: find exact max size */
#define HIGH_BAND_MAX_SIZE 16
#define NB_LSP_COEFS 10
/* XXX: is it a suitable value ? */
#define MAX_CODED_SUPERFRAME_SIZE 16384
#define MAX_CHANNELS 2
#define NOISE_TAB_SIZE 8192
#define LSP_POW_BITS 7
//FIXME should be in wmadec
#define VLCBITS 9
#define VLCMAX ((22+VLCBITS-1)/VLCBITS)
typedef float WMACoef; ///< type for decoded coefficients, int16_t would be enough for wma 1/2
typedef struct CoefVLCTable {
int n; ///< total number of codes
int max_level;
const uint32_t *huffcodes; ///< VLC bit values
const uint8_t *huffbits; ///< VLC bit size
const uint16_t *levels; ///< table to build run/level tables
} CoefVLCTable;
typedef struct WMACodecContext {
AVCodecContext* avctx;
GetBitContext gb;
PutBitContext pb;
int version; ///< 1 = 0x160 (WMAV1), 2 = 0x161 (WMAV2)
int use_bit_reservoir;
int use_variable_block_len;
int use_exp_vlc; ///< exponent coding: 0 = lsp, 1 = vlc + delta
int use_noise_coding; ///< true if perceptual noise is added
int byte_offset_bits;
VLC exp_vlc;
int exponent_sizes[BLOCK_NB_SIZES];
uint16_t exponent_bands[BLOCK_NB_SIZES][25];
int high_band_start[BLOCK_NB_SIZES]; ///< index of first coef in high band
int coefs_start; ///< first coded coef
int coefs_end[BLOCK_NB_SIZES]; ///< max number of coded coefficients
int exponent_high_sizes[BLOCK_NB_SIZES];
int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];
VLC hgain_vlc;
/* coded values in high bands */
int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
/* there are two possible tables for spectral coefficients */
//FIXME the following 3 tables should be shared between decoders
VLC coef_vlc[2];
uint16_t *run_table[2];
float *level_table[2];
uint16_t *int_table[2];
const CoefVLCTable *coef_vlcs[2];
/* frame info */
int frame_len; ///< frame length in samples
int frame_len_bits; ///< frame_len = 1 << frame_len_bits
int nb_block_sizes; ///< number of block sizes
/* block info */
int reset_block_lengths;
int block_len_bits; ///< log2 of current block length
int next_block_len_bits; ///< log2 of next block length
int prev_block_len_bits; ///< log2 of prev block length
int block_len; ///< block length in samples
int block_num; ///< block number in current frame
int block_pos; ///< current position in frame
uint8_t ms_stereo; ///< true if mid/side stereo mode
uint8_t channel_coded[MAX_CHANNELS]; ///< true if channel is coded
int exponents_bsize[MAX_CHANNELS]; ///< log2 ratio frame/exp. length
DECLARE_ALIGNED(32, float, exponents)[MAX_CHANNELS][BLOCK_MAX_SIZE];
float max_exponent[MAX_CHANNELS];
WMACoef coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
DECLARE_ALIGNED(32, float, coefs)[MAX_CHANNELS][BLOCK_MAX_SIZE];
DECLARE_ALIGNED(32, FFTSample, output)[BLOCK_MAX_SIZE * 2];
FFTContext mdct_ctx[BLOCK_NB_SIZES];
float *windows[BLOCK_NB_SIZES];
/* output buffer for one frame and the last for IMDCT windowing */
DECLARE_ALIGNED(32, float, frame_out)[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
/* last frame info */
uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + FF_INPUT_BUFFER_PADDING_SIZE]; /* padding added */
int last_bitoffset;
int last_superframe_len;
float noise_table[NOISE_TAB_SIZE];
int noise_index;
float noise_mult; /* XXX: suppress that and integrate it in the noise array */
/* lsp_to_curve tables */
float lsp_cos_table[BLOCK_MAX_SIZE];
float lsp_pow_e_table[256];
float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
FmtConvertContext fmt_conv;
AVFloatDSPContext fdsp;
#ifdef TRACE
int frame_count;
#endif
} WMACodecContext;
extern const uint16_t ff_wma_critical_freqs[25];
extern const uint16_t ff_wma_hgain_huffcodes[37];
extern const uint8_t ff_wma_hgain_huffbits[37];
extern const float ff_wma_lsp_codebook[NB_LSP_COEFS][16];
extern const uint32_t ff_aac_scalefactor_code[121];
extern const uint8_t ff_aac_scalefactor_bits[121];
int ff_wma_init(AVCodecContext * avctx, int flags2);
int ff_wma_total_gain_to_bits(int total_gain);
int ff_wma_end(AVCodecContext *avctx);
unsigned int ff_wma_get_large_val(GetBitContext* gb);
int ff_wma_run_level_decode(AVCodecContext* avctx, GetBitContext* gb,
VLC *vlc,
const float *level_table, const uint16_t *run_table,
int version, WMACoef *ptr, int offset,
int num_coefs, int block_len, int frame_len_bits,
int coef_nb_bits);
#endif /* AVCODEC_WMA_H */
Reference in New Issue View Git Blame Copy Permalink