#include <stdint.h>
+/**
+ * Number of mantissa bits written for each bap value.
+ * bap values with fractional bits are set to 0 and are calculated separately.
+ */
+extern const uint16_t ff_ac3_bap_bits[16];
+
typedef struct AC3DSPContext {
/**
* Set each encoded exponent in a block to the minimum of itself and the
* 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);
+
+ /**
+ * Update bap counts using the supplied array of bap.
+ *
+ * @param[out] mant_cnt bap counts for 1 block
+ * @param[in] bap array of bap, pointing to start coef bin
+ * @param[in] len number of elements to process
+ */
+ void (*update_bap_counts)(uint16_t mant_cnt[16], uint8_t *bap, int len);
+
+ /**
+ * Calculate the number of bits needed to encode a set of mantissas.
+ *
+ * @param[in] mant_cnt bap counts for all blocks
+ * @return mantissa bit count
+ */
+ int (*compute_mantissa_size)(uint16_t mant_cnt[6][16]);
+
+ void (*extract_exponents)(uint8_t *exp, int32_t *coef, int nb_coefs);
+
+ void (*downmix)(float **samples, float (*matrix)[2], int out_ch,
+ int in_ch, int len);
+
+ /**
+ * Apply symmetric window in 16-bit fixed-point.
+ * @param output destination array
+ * constraints: 16-byte aligned
+ * @param input source array
+ * constraints: 16-byte aligned
+ * @param window window array
+ * constraints: 16-byte aligned, at least len/2 elements
+ * @param len full window length
+ * constraints: multiple of ? greater than zero
+ */
+ void (*apply_window_int16)(int16_t *output, const int16_t *input,
+ const int16_t *window, unsigned int len);
} AC3DSPContext;
void ff_ac3dsp_init (AC3DSPContext *c, int bit_exact);
+void ff_ac3dsp_init_arm(AC3DSPContext *c, int bit_exact);
void ff_ac3dsp_init_x86(AC3DSPContext *c, int bit_exact);
#endif /* AVCODEC_AC3DSP_H */