FFmpeg/libavcodec/wma.h
Ian Braithwaite 5bd526d9ad WMA decoder improvement, output closer to the dmo binary.
Patch by Ian Braithwaite ian braithwaite dot dk

[Ffmpeg-devel] WMA decoder improvement, 2007-03-28 15:50

Originally committed as revision 8627 to svn://svn.ffmpeg.org/ffmpeg/trunk
2007-04-04 13:49:55 +00:00

151 lines
5.6 KiB
C

/*
* WMA compatible codec
* Copyright (c) 2002-2007 The FFmpeg Project.
*
* 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 WMA_H
#define WMA_H
#include "bitstream.h"
#include "dsputil.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 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 sample_rate;
int nb_channels;
int bit_rate;
int version; ///< 1 = 0x160 (WMAV1), 2 = 0x161 (WMAV2)
int block_align;
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];
uint16_t *level_table[2];
uint16_t *int_table[2];
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_16(float, exponents[MAX_CHANNELS][BLOCK_MAX_SIZE]);
float max_exponent[MAX_CHANNELS];
int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
DECLARE_ALIGNED_16(float, coefs[MAX_CHANNELS][BLOCK_MAX_SIZE]);
DECLARE_ALIGNED_16(FFTSample, output[BLOCK_MAX_SIZE * 2]);
MDCTContext mdct_ctx[BLOCK_NB_SIZES];
float *windows[BLOCK_NB_SIZES];
DECLARE_ALIGNED_16(FFTSample, mdct_tmp[BLOCK_MAX_SIZE]); ///< temporary storage for imdct
/* output buffer for one frame and the last for IMDCT windowing */
DECLARE_ALIGNED_16(float, frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2]);
/* last frame info */
uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* 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)];
DSPContext dsp;
#ifdef TRACE
int frame_count;
#endif
} WMACodecContext;
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_wma_scale_huffcodes[121];
extern const uint8_t ff_wma_scale_huffbits[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);
#endif