/*
- * Common code between AC3 and E-AC3 decoder
+ * Common code between the AC-3 and E-AC-3 decoders
* Copyright (c) 2007 Bartlomiej Wolowiec <bartek.wolowiec@gmail.com>
*
* This file is part of FFmpeg.
/**
* @file ac3.h
- * Common code between AC3 and E-AC3 decoder.
+ * Common code between the AC-3 and E-AC-3 decoders.
*/
#ifndef FFMPEG_AC3DEC_H
#define FFMPEG_AC3DEC_H
-#include "libavutil/random.h"
-#include "ac3tab.h"
+#include "libavutil/lfg.h"
#include "ac3.h"
#include "bitstream.h"
#include "dsputil.h"
#define AC3_MAX_COEFS 256
#define AC3_BLOCK_SIZE 256
+#define MAX_BLOCKS 6
typedef struct {
AVCodecContext *avctx; ///< parent context
///@defgroup bsi bit stream information
///@{
- int frame_type; ///< frame type (strmtyp)
+ int frame_type; ///< frame type (strmtyp)
int substreamid; ///< substream identification
int frame_size; ///< current frame size, in bytes
int bit_rate; ///< stream bit rate, in bits-per-second
int sample_rate; ///< sample frequency, in Hz
int num_blocks; ///< number of audio blocks
- int channel_mode; ///< channel mode (acmod)
+ int channel_mode; ///< channel mode (acmod)
int lfe_on; ///< lfe channel in use
+ int channel_map; ///< custom channel map
int center_mix_level; ///< Center mix level index
int surround_mix_level; ///< Surround mix level index
+ int eac3; ///< indicates if current frame is E-AC-3
///@}
+///@defgroup audfrm frame syntax parameters
+ int snr_offset_strategy; ///< SNR offset strategy (snroffststr)
+ int block_switch_syntax; ///< block switch syntax enabled (blkswe)
+ int dither_flag_syntax; ///< dither flag syntax enabled (dithflage)
+ int bit_allocation_syntax; ///< bit allocation model syntax enabled (bamode)
+ int fast_gain_syntax; ///< fast gain codes enabled (frmfgaincode)
+ int dba_syntax; ///< delta bit allocation syntax enabled (dbaflde)
+ int skip_syntax; ///< skip field syntax enabled (skipflde)
+ ///@}
+
///@defgroup cpl standard coupling
- int cpl_in_use; ///< coupling in use
- int channel_in_cpl[AC3_MAX_CHANNELS]; ///< channel in coupling
- int phase_flags_in_use; ///< phase flags in use
- int phase_flags[18]; ///< phase flags
- int num_cpl_subbands; ///< number of coupling sub bands
- int num_cpl_bands; ///< number of coupling bands
- int cpl_band_struct[18]; ///< coupling band structure
- int cpl_coords[AC3_MAX_CHANNELS][18]; ///< coupling coordinates
+ int cpl_in_use[MAX_BLOCKS]; ///< coupling in use (cplinu)
+ int cpl_strategy_exists[MAX_BLOCKS]; ///< coupling strategy exists (cplstre)
+ int channel_in_cpl[AC3_MAX_CHANNELS]; ///< channel in coupling (chincpl)
+ int phase_flags_in_use; ///< phase flags in use (phsflginu)
+ int phase_flags[18]; ///< phase flags (phsflg)
+ int num_cpl_subbands; ///< number of coupling sub bands (ncplsubnd)
+ int num_cpl_bands; ///< number of coupling bands (ncplbnd)
+ uint8_t cpl_band_struct[18]; ///< coupling band structure (cplbndstrc)
+ int firstchincpl; ///< first channel in coupling
+ int first_cpl_coords[AC3_MAX_CHANNELS]; ///< first coupling coordinates states (firstcplcos)
+ int cpl_coords[AC3_MAX_CHANNELS][18]; ///< coupling coordinates (cplco)
+///@}
+
+///@defgroup aht adaptive hybrid transform
+ int channel_uses_aht[AC3_MAX_CHANNELS]; ///< channel AHT in use (chahtinu)
+ int pre_mantissa[AC3_MAX_CHANNELS][AC3_MAX_COEFS][MAX_BLOCKS]; ///< pre-IDCT mantissas
///@}
///@defgroup channel channel
int channels; ///< number of total channels
int lfe_ch; ///< index of LFE channel
float downmix_coeffs[AC3_MAX_CHANNELS][2]; ///< stereo downmix coefficients
- float downmix_coeff_adjust[2]; ///< adjustment needed for each output channel when downmixing
int downmixed; ///< indicates if coeffs are currently downmixed
int output_mode; ///< output channel configuration
int out_channels; ///< number of output channels
///@}
///@defgroup bandwidth bandwidth
- int start_freq[AC3_MAX_CHANNELS]; ///< start frequency bin
- int end_freq[AC3_MAX_CHANNELS]; ///< end frequency bin
+ int start_freq[AC3_MAX_CHANNELS]; ///< start frequency bin (strtmant)
+ int end_freq[AC3_MAX_CHANNELS]; ///< end frequency bin (endmant)
///@}
///@defgroup rematrixing rematrixing
- int num_rematrixing_bands; ///< number of rematrixing bands
- int rematrixing_flags[4]; ///< rematrixing flags
+ int num_rematrixing_bands; ///< number of rematrixing bands (nrematbnd)
+ int rematrixing_flags[4]; ///< rematrixing flags (rematflg)
///@}
///@defgroup exponents exponents
- int num_exp_groups[AC3_MAX_CHANNELS]; ///< Number of exponent groups
+ int num_exp_groups[AC3_MAX_CHANNELS]; ///< Number of exponent groups (nexpgrp)
int8_t dexps[AC3_MAX_CHANNELS][AC3_MAX_COEFS]; ///< decoded exponents
- int exp_strategy[AC3_MAX_CHANNELS]; ///< exponent strategies
+ int exp_strategy[MAX_BLOCKS][AC3_MAX_CHANNELS]; ///< exponent strategies (expstr)
///@}
///@defgroup bitalloc bit allocation
AC3BitAllocParameters bit_alloc_params; ///< bit allocation parameters
- int snr_offset[AC3_MAX_CHANNELS]; ///< signal-to-noise ratio offsets
- int fast_gain[AC3_MAX_CHANNELS]; ///< fast gain values (signal-to-mask ratio)
+ int first_cpl_leak; ///< first coupling leak state (firstcplleak)
+ int snr_offset[AC3_MAX_CHANNELS]; ///< signal-to-noise ratio offsets (snroffst)
+ int fast_gain[AC3_MAX_CHANNELS]; ///< fast gain values/SMR's (fgain)
uint8_t bap[AC3_MAX_CHANNELS][AC3_MAX_COEFS]; ///< bit allocation pointers
int16_t psd[AC3_MAX_CHANNELS][AC3_MAX_COEFS]; ///< scaled exponents
int16_t band_psd[AC3_MAX_CHANNELS][50]; ///< interpolated exponents
///@}
///@defgroup dithering zero-mantissa dithering
- int dither_all; ///< true if all channels are dithered
- int dither_flag[AC3_MAX_CHANNELS]; ///< dither flags
- AVRandomState dith_state; ///< for dither generation
+ int dither_flag[AC3_MAX_CHANNELS]; ///< dither flags (dithflg)
+ AVLFG dith_state; ///< for dither generation
///@}
///@defgroup imdct IMDCT
- int block_switch[AC3_MAX_CHANNELS]; ///< block switch flags
+ int block_switch[AC3_MAX_CHANNELS]; ///< block switch flags (blksw)
MDCTContext imdct_512; ///< for 512 sample IMDCT
MDCTContext imdct_256; ///< for 256 sample IMDCT
///@}
float mul_bias; ///< scaling for float_to_int16 conversion
///@}
- int fixed_coeffs[AC3_MAX_CHANNELS][AC3_MAX_COEFS]; ///> fixed-point transform coefficients
+ DECLARE_ALIGNED_16(int, fixed_coeffs[AC3_MAX_CHANNELS][AC3_MAX_COEFS]); ///> fixed-point transform coefficients
///@defgroup arrays aligned arrays
DECLARE_ALIGNED_16(float, transform_coeffs[AC3_MAX_CHANNELS][AC3_MAX_COEFS]); ///< transform coefficients
DECLARE_ALIGNED_16(float, delay[AC3_MAX_CHANNELS][AC3_BLOCK_SIZE]); ///< delay - added to the next block
DECLARE_ALIGNED_16(float, window[AC3_BLOCK_SIZE]); ///< window coefficients
- DECLARE_ALIGNED_16(float, tmp_output[AC3_BLOCK_SIZE*2]); ///< temporary storage for output before windowing
- DECLARE_ALIGNED_16(float, tmp_imdct[AC3_BLOCK_SIZE]); ///< temporary storage for imdct transform
+ DECLARE_ALIGNED_16(float, tmp_output[AC3_BLOCK_SIZE]); ///< temporary storage for output before windowing
DECLARE_ALIGNED_16(float, output[AC3_MAX_CHANNELS][AC3_BLOCK_SIZE]); ///< output after imdct transform and windowing
- DECLARE_ALIGNED_16(short, int_output[AC3_MAX_CHANNELS-1][AC3_BLOCK_SIZE]); ///< final 16-bit integer output
///@}
} AC3DecodeContext;
+/**
+ * Parse the E-AC-3 frame header.
+ * This parses both the bit stream info and audio frame header.
+ */
+int ff_eac3_parse_header(AC3DecodeContext *s);
+
+/**
+ * Decode mantissas in a single channel for the entire frame.
+ * This is used when AHT mode is enabled.
+ */
+void ff_eac3_decode_transform_coeffs_aht_ch(AC3DecodeContext *s, int ch);
+
#endif /* FFMPEG_AC3DEC_H */
projects / ffmpeg / blobdiff