1 /* 2 * WMA compatible decoder 3 * Copyright (c) 2002 The FFmpeg Project. 4 * 5 * This library is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU Lesser General Public 7 * License as published by the Free Software Foundation; either 8 * version 2 of the License, or (at your option) any later version. 9 * 10 * This library is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 * Lesser General Public License for more details. 14 * 15 * You should have received a copy of the GNU Lesser General Public 16 * License along with this library; if not, write to the Free Software 17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 18 */ 19 20 #ifndef _WMADEC_H 21 #define _WMADEC_H 22 23 #include <inttypes.h> 24 #include <math.h> 25 26 #include "asf.h" 27 #include "bitstream.h" /* For GetBitContext */ 28 #include "mdct.h" 29 30 #undef TRACE 31 32 /* size of blocks */ 33 #define BLOCK_MIN_BITS 7 34 #define BLOCK_MAX_BITS 11 35 #define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS) 36 37 #define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1) 38 39 /* XXX: find exact max size */ 40 #define HIGH_BAND_MAX_SIZE 16 41 42 #define NB_LSP_COEFS 10 43 44 /* XXX: is it a suitable value ? */ 45 #define MAX_CODED_SUPERFRAME_SIZE 16384 46 47 #define M_PI_F 0x3243f // in fixed 32 format 48 #define TWO_M_PI_F 0x6487f //in fixed 32 49 50 #define MAX_CHANNELS 2 51 52 #define NOISE_TAB_SIZE 8192 53 54 #define LSP_POW_BITS 7 55 56 typedef struct WMADecodeContext 57 { 58 GetBitContext gb; 59 60 int nb_block_sizes; /* number of block sizes */ 61 62 int sample_rate; 63 int nb_channels; 64 int bit_rate; 65 int version; /* 1 = 0x160 (WMAV1), 2 = 0x161 (WMAV2) */ 66 int block_align; 67 int use_bit_reservoir; 68 int use_variable_block_len; 69 int use_exp_vlc; /* exponent coding: 0 = lsp, 1 = vlc + delta */ 70 int use_noise_coding; /* true if perceptual noise is added */ 71 int byte_offset_bits; 72 VLC exp_vlc; 73 int exponent_sizes[BLOCK_NB_SIZES]; 74 uint16_t exponent_bands[BLOCK_NB_SIZES][25]; 75 int high_band_start[BLOCK_NB_SIZES]; /* index of first coef in high band */ 76 int coefs_start; /* first coded coef */ 77 int coefs_end[BLOCK_NB_SIZES]; /* max number of coded coefficients */ 78 int exponent_high_sizes[BLOCK_NB_SIZES]; 79 int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE]; 80 VLC hgain_vlc; 81 82 /* coded values in high bands */ 83 int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE]; 84 int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE]; 85 86 /* there are two possible tables for spectral coefficients */ 87 VLC coef_vlc[2]; 88 uint16_t *run_table[2]; 89 uint16_t *level_table[2]; 90 /* frame info */ 91 int frame_len; /* frame length in samples */ 92 int frame_len_bits; /* frame_len = 1 << frame_len_bits */ 93 94 /* block info */ 95 int reset_block_lengths; 96 int block_len_bits; /* log2 of current block length */ 97 int next_block_len_bits; /* log2 of next block length */ 98 int prev_block_len_bits; /* log2 of prev block length */ 99 int block_len; /* block length in samples */ 100 int block_num; /* block number in current frame */ 101 int block_pos; /* current position in frame */ 102 uint8_t ms_stereo; /* true if mid/side stereo mode */ 103 uint8_t channel_coded[MAX_CHANNELS]; /* true if channel is coded */ 104 int exponents_bsize[MAX_CHANNELS]; // log2 ratio frame/exp. length 105 int32_t exponents[MAX_CHANNELS][BLOCK_MAX_SIZE]; 106 int32_t max_exponent[MAX_CHANNELS]; 107 int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE]; 108 int32_t (*coefs)[MAX_CHANNELS][BLOCK_MAX_SIZE]; 109 MDCTContext mdct_ctx[BLOCK_NB_SIZES]; 110 int32_t *windows[BLOCK_NB_SIZES]; 111 /* output buffer for one frame and the last for IMDCT windowing */ 112 int32_t frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2]; 113 /* last frame info */ 114 uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */ 115 int last_bitoffset; 116 int last_superframe_len; 117 int32_t *noise_table; 118 int noise_index; 119 int32_t noise_mult; /* XXX: suppress that and integrate it in the noise array */ 120 /* lsp_to_curve tables */ 121 int32_t lsp_cos_table[BLOCK_MAX_SIZE]; 122 int64_t lsp_pow_e_table[256]; 123 int32_t lsp_pow_m_table1[(1 << LSP_POW_BITS)]; 124 int32_t lsp_pow_m_table2[(1 << LSP_POW_BITS)]; 125 126 /* State of current superframe decoding */ 127 int bit_offset; 128 int nb_frames; 129 int current_frame; 130 131 #ifdef TRACE 132 133 int frame_count; 134 #endif 135 } 136 WMADecodeContext; 137 138 int wma_decode_init(WMADecodeContext* s, asf_waveformatex_t *wfx); 139 int wma_decode_superframe_init(WMADecodeContext* s, 140 uint8_t *buf, int buf_size); 141 int wma_decode_superframe_frame(WMADecodeContext* s, 142 int32_t *samples, 143 uint8_t *buf, int buf_size); 144 #endif 145