diff options
Diffstat (limited to 'libavcodec/ac3dsp.h')
| -rw-r--r-- | libavcodec/ac3dsp.h | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/libavcodec/ac3dsp.h b/libavcodec/ac3dsp.h index 66dc32bd03..08680f382d 100644 --- a/libavcodec/ac3dsp.h +++ b/libavcodec/ac3dsp.h @@ -81,6 +81,30 @@ typedef struct AC3DSPContext { * constraints: multiple of 32 greater than zero */ void (*float_to_fixed24)(int32_t *dst, const float *src, unsigned int len); + + /** + * Calculate bit allocation pointers. + * The SNR is the difference between the masking curve and the signal. AC-3 + * uses this value for each frequency bin to allocate bits. The snroffset + * parameter is a global adjustment to the SNR for all bins. + * + * @param[in] mask masking curve + * @param[in] psd signal power for each frequency bin + * @param[in] start starting bin location + * @param[in] end ending bin location + * @param[in] snr_offset SNR adjustment + * @param[in] floor noise floor + * @param[in] bap_tab look-up table for bit allocation pointers + * @param[out] bap bit allocation pointers + */ + void (*bit_alloc_calc_bap)(int16_t *mask, int16_t *psd, int start, int end, + int snr_offset, int floor, + const uint8_t *bap_tab, uint8_t *bap); + + /** + * Calculate the number of bits needed to encode a set of mantissas. + */ + int (*compute_mantissa_size)(int mant_cnt[5], uint8_t *bap, int nb_coefs); } AC3DSPContext; void ff_ac3dsp_init (AC3DSPContext *c, int bit_exact); |