#define AC3_OUTPUT_LFEON 8
+#define AC3_MAX_COEFS 256
+#define AC3_BLOCK_SIZE 256
+#define MAX_BLOCKS 6
+
typedef struct {
- int num_blocks; ///< number of audio blocks
- int channel_mode; ///< channel mode (acmod)
- int block_switch[AC3_MAX_CHANNELS]; ///< block switch flags
- int dither_flag[AC3_MAX_CHANNELS]; ///< dither flags
- int dither_all; ///< true if all channels are dithered
- 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 cpl_band_struct[18]; ///< coupling band structure
- int num_rematrixing_bands; ///< number of rematrixing bands
- int rematrixing_flags[4]; ///< rematrixing flags
- int exp_strategy[AC3_MAX_CHANNELS]; ///< exponent strategies
- 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 dba_mode[AC3_MAX_CHANNELS]; ///< delta bit allocation mode
- int dba_nsegs[AC3_MAX_CHANNELS]; ///< number of delta segments
- uint8_t dba_offsets[AC3_MAX_CHANNELS][8]; ///< delta segment offsets
- uint8_t dba_lengths[AC3_MAX_CHANNELS][8]; ///< delta segment lengths
- uint8_t dba_values[AC3_MAX_CHANNELS][8]; ///< delta values for each segment
+ AVCodecContext *avctx; ///< parent context
+ GetBitContext gbc; ///< bitstream reader
+ uint8_t *input_buffer; ///< temp buffer to prevent overread
- int sample_rate; ///< sample frequency, in Hz
- int bit_rate; ///< stream bit rate, in bits-per-second
- int frame_type; ///< frame type (strmtyp)
+///@defgroup bsi bit stream information
+///@{
+ int frame_type; ///< frame type (strmtyp)
int substreamid; ///< substream identification
int frame_size; ///< current frame size, in bytes
-
- int channels; ///< number of total channels
- int fbw_channels; ///< number of full-bandwidth channels
+ 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 lfe_on; ///< lfe channel in use
- int lfe_ch; ///< index of LFE channel
- int output_mode; ///< output channel configuration
- int out_channels; ///< number of output channels
-
+ 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[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)
+ int 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[6][AC3_MAX_CHANNELS][AC3_MAX_COEFS]; ///< pre-IDCT mantissas
+///@}
+
+///@defgroup channel channel
+ int fbw_channels; ///< number of full-bandwidth channels
+ 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
- float dynamic_range[2]; ///< dynamic range
- int cpl_coords[AC3_MAX_CHANNELS][18]; ///< coupling coordinates
- int num_cpl_bands; ///< number of coupling bands
- int num_cpl_subbands; ///< number of coupling sub bands
- int start_freq[AC3_MAX_CHANNELS]; ///< start frequency bin
- int end_freq[AC3_MAX_CHANNELS]; ///< end frequency bin
- AC3BitAllocParameters bit_alloc_params; ///< bit allocation parameters
-
- int num_exp_groups[AC3_MAX_CHANNELS]; ///< Number of exponent groups
- int8_t dexps[AC3_MAX_CHANNELS][256]; ///< decoded exponents
- uint8_t bap[AC3_MAX_CHANNELS][256]; ///< bit allocation pointers
- int16_t psd[AC3_MAX_CHANNELS][256]; ///< scaled exponents
- int16_t band_psd[AC3_MAX_CHANNELS][50]; ///< interpolated exponents
- int16_t mask[AC3_MAX_CHANNELS][50]; ///< masking curve values
-
- int fixed_coeffs[AC3_MAX_CHANNELS][256]; ///> fixed-point transform coefficients
- DECLARE_ALIGNED_16(float, transform_coeffs[AC3_MAX_CHANNELS][256]); ///< transform 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 dynrng dynamic range
+ float dynamic_range[2]; ///< dynamic range
+///@}
+
+///@defgroup bandwidth bandwidth
+ 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 (nrematbnd)
+ int rematrixing_flags[4]; ///< rematrixing flags (rematflg)
+///@}
- /* For IMDCT. */
+///@defgroup exponents exponents
+ 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[MAX_BLOCKS][AC3_MAX_CHANNELS]; ///< exponent strategies (expstr)
+///@}
+
+///@defgroup bitalloc bit allocation
+ AC3BitAllocParameters bit_alloc_params; ///< bit allocation parameters
+ 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
+ int16_t mask[AC3_MAX_CHANNELS][50]; ///< masking curve values
+ int dba_mode[AC3_MAX_CHANNELS]; ///< delta bit allocation mode
+ int dba_nsegs[AC3_MAX_CHANNELS]; ///< number of delta segments
+ uint8_t dba_offsets[AC3_MAX_CHANNELS][8]; ///< delta segment offsets
+ uint8_t dba_lengths[AC3_MAX_CHANNELS][8]; ///< delta segment lengths
+ uint8_t dba_values[AC3_MAX_CHANNELS][8]; ///< delta values for each segment
+///@}
+
+///@defgroup dithering zero-mantissa dithering
+ int dither_all; ///< true if all channels are dithered
+ int dither_flag[AC3_MAX_CHANNELS]; ///< dither flags (dithflg)
+ AVRandomState dith_state; ///< for dither generation
+///@}
+
+///@defgroup imdct IMDCT
+ int block_switch[AC3_MAX_CHANNELS]; ///< block switch flags (blksw)
MDCTContext imdct_512; ///< for 512 sample IMDCT
MDCTContext imdct_256; ///< for 256 sample IMDCT
- DSPContext dsp; ///< for optimization
- float add_bias; ///< offset for float_to_int16 conversion
- float mul_bias; ///< scaling for float_to_int16 conversion
-
- DECLARE_ALIGNED_16(float, output[AC3_MAX_CHANNELS][256]); ///< output after imdct transform and windowing
- DECLARE_ALIGNED_16(short, int_output[AC3_MAX_CHANNELS-1][256]); ///< final 16-bit integer output
- DECLARE_ALIGNED_16(float, delay[AC3_MAX_CHANNELS][256]); ///< delay - added to the next block
- DECLARE_ALIGNED_16(float, tmp_imdct[256]); ///< temporary storage for imdct transform
- DECLARE_ALIGNED_16(float, tmp_output[512]); ///< temporary storage for output before windowing
- DECLARE_ALIGNED_16(float, window[256]); ///< window coefficients
-
- /* Miscellaneous. */
- GetBitContext gbc; ///< bitstream reader
- AVRandomState dith_state; ///< for dither generation
- AVCodecContext *avctx; ///< parent context
- uint8_t *input_buffer; ///< temp buffer to prevent overread
+///@}
+
+///@defgroup opt optimization
+ DSPContext dsp; ///< for optimization
+ float add_bias; ///< offset for float_to_int16 conversion
+ float mul_bias; ///< scaling for float_to_int16 conversion
+///@}
+
+ 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, 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;
#endif /* FFMPEG_AC3DEC_H */