Remove duplicate #includes, avcodec.h #includes common.h.

[ffmpeg] / libavcodec / ac3.h

diff --git a/libavcodec/ac3.h b/libavcodec/ac3.h
index 81a322c0e6803e7446d6d4cb3ad72746a67b43d7..bfaf7d0db2215b9543bd885a72a284c2c99122dc 100644 (file)
--- a/libavcodec/ac3.h
+++ b/libavcodec/ac3.h
@@ -24,6 +24,11 @@
  * Common code between AC3 encoder and decoder.
  */
 
+#ifndef AC3_H
+#define AC3_H
+
+#include "ac3tab.h"
+
 #define AC3_MAX_CODED_FRAME_SIZE 3840 /* in bytes */
 #define AC3_MAX_CHANNELS 6 /* including LFE channel */
 
@@ -45,15 +50,106 @@ typedef struct AC3BitAllocParameters {
     int cplfleak, cplsleak;
 } AC3BitAllocParameters;
 
-#if 0
-extern const uint16_t ac3_freqs[3];
-extern const uint16_t ac3_bitratetab[19];
-extern const int16_t ac3_window[256];
-extern const uint8_t sdecaytab[4];
-extern const uint8_t fdecaytab[4];
-extern const uint16_t sgaintab[4];
-extern const uint16_t dbkneetab[4];
-extern const uint16_t floortab[8];
-extern const uint16_t fgaintab[8];
-#endif
+/**
+ * @struct AC3HeaderInfo
+ * Coded AC-3 header values up to the lfeon element, plus derived values.
+ */
+typedef struct {
+    /** @defgroup coded Coded elements
+     * @{
+     */
+    uint16_t sync_word;
+    uint16_t crc1;
+    uint8_t fscod;
+    uint8_t frmsizecod;
+    uint8_t bsid;
+    uint8_t bsmod;
+    uint8_t acmod;
+    uint8_t cmixlev;
+    uint8_t surmixlev;
+    uint8_t dsurmod;
+    uint8_t lfeon;
+    /** @} */
+
+    /** @defgroup derived Derived values
+     * @{
+     */
+    uint8_t halfratecod;
+    uint16_t sample_rate;
+    uint32_t bit_rate;
+    uint8_t channels;
+    uint16_t frame_size;
+    /** @} */
+} AC3HeaderInfo;
+
+
+void ac3_common_init(void);
+
+/**
+ * Calculates the log power-spectral density of the input signal.
+ * This gives a rough estimate of signal power in the frequency domain by using
+ * the spectral envelope (exponents).  The psd is also separately grouped
+ * into critical bands for use in the calculating the masking curve.
+ * 128 units in psd = -6 dB.  The dbknee parameter in AC3BitAllocParameters
+ * determines the reference level.
+ *
+ * @param[in]  exp        frequency coefficient exponents
+ * @param[in]  start      starting bin location
+ * @param[in]  end        ending bin location
+ * @param[out] psd        signal power for each frequency bin
+ * @param[out] bndpsd     signal power for each critical band
+ */
+void ff_ac3_bit_alloc_calc_psd(int8_t *exp, int start, int end, int16_t *psd,
+                               int16_t *bndpsd);
+
+/**
+ * Calculates the masking curve.
+ * First, the excitation is calculated using parameters in \p s and the signal
+ * power in each critical band.  The excitation is compared with a predefined
+ * hearing threshold table to produce the masking curve.  If delta bit
+ * allocation information is provided, it is used for adjusting the masking
+ * curve, usually to give a closer match to a better psychoacoustic model.
+ *
+ * @param[in]  s          adjustable bit allocation parameters
+ * @param[in]  bndpsd     signal power for each critical band
+ * @param[in]  start      starting bin location
+ * @param[in]  end        ending bin location
+ * @param[in]  fgain      fast gain (estimated signal-to-mask ratio)
+ * @param[in]  is_lfe     whether or not the channel being processed is the LFE
+ * @param[in]  deltbae    delta bit allocation exists (none, reuse, or new)
+ * @param[in]  deltnseg   number of delta segments
+ * @param[in]  deltoffst  location offsets for each segment
+ * @param[in]  deltlen    length of each segment
+ * @param[in]  deltba     delta bit allocation for each segment
+ * @param[out] mask       calculated masking curve
+ */
+void ff_ac3_bit_alloc_calc_mask(AC3BitAllocParameters *s, int16_t *bndpsd,
+                                int start, int end, int fgain, int is_lfe,
+                                int deltbae, int deltnseg, uint8_t *deltoffst,
+                                uint8_t *deltlen, uint8_t *deltba,
+                                int16_t *mask);
+
+/**
+ * Calculates 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 \p 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]  snroffset  SNR adjustment
+ * @param[in]  floor      noise floor
+ * @param[out] bap        bit allocation pointers
+ */
+void ff_ac3_bit_alloc_calc_bap(int16_t *mask, int16_t *psd, int start, int end,
+                               int snroffset, int floor, uint8_t *bap);
+
+void ac3_parametric_bit_allocation(AC3BitAllocParameters *s, uint8_t *bap,
+                                   int8_t *exp, int start, int end,
+                                   int snroffset, int fgain, int is_lfe,
+                                   int deltbae,int deltnseg,
+                                   uint8_t *deltoffst, uint8_t *deltlen, uint8_t *deltba);
 
+#endif /* AC3_H */