/*
- * part of QCELP decoder
+ * QCELP decoder
* Copyright (c) 2007 Reynaldo H. Verdejo Pinochet
*
* This file is part of FFmpeg.
#ifndef AVCODEC_QCELPDATA_H
#define AVCODEC_QCELPDATA_H
+/**
+ * @file libavcodec/qcelpdata.h
+ * Data tables for the QCELP decoder
+ * @author Reynaldo H. Verdejo Pinochet
+ * @remark FFmpeg merging spearheaded by Kenan Gillet
+ * @remark Development mentored by Benjamin Larson
+ */
+
+#include <stddef.h>
#include <stdint.h>
+#include "libavutil/common.h"
+
+/**
+ * QCELP unpacked data frame
+ */
+typedef struct {
+/// @defgroup qcelp_codebook_parameters QCELP excitation codebook parameters
+/// @{
+ uint8_t cbsign[16]; ///!< sign of the codebook gain for each codebook subframe
+ uint8_t cbgain[16]; ///!< unsigned codebook gain for each codebook subframe
+ uint8_t cindex[16]; ///!< codebook index for each codebook subframe
+/// @}
+
+/// @defgroup qcelp_pitch_parameters QCELP pitch prediction parameters
+/// @{
+ uint8_t plag[4]; ///!< pitch lag for each pitch subframe
+ uint8_t pfrac[4]; ///!< fractional pitch lag for each pitch subframe
+ uint8_t pgain[4]; ///!< pitch gain for each pitch subframe
+/// @}
+
+ /**
+ * line spectral pair frequencies (LSP) for RATE_OCTAVE,
+ * line spectral pair frequencies grouped into five vectors
+ * of dimension two (LSPV) for other rates
+ */
+ uint8_t lspv[10];
+
+ /**
+ * reserved bits only present in bitrate 1, 1/4 and 1/8 packets
+ */
+ uint8_t reserved;
+} QCELPFrame;
/**
* pre-calculated table for hammsinc function
uint8_t bitlen; /*!< number of bits to read */
} QCELPBitmap;
-#define QCELP_OF(variable, bit, len) {offsetof(QCELPContext, variable), bit, len}
+#define QCELP_OF(variable, bit, len) {offsetof(QCELPFrame, variable), bit, len}
/**
* bitmap unpacking tables for RATE_FULL
qcelp_rate_full_bitmap,
};
-static const uint16_t qcelp_bits_per_rate[5] = {
+static const uint16_t qcelp_unpacking_bitmaps_lengths[5] = {
0, ///!< for SILENCE rate
FF_ARRAY_ELEMS(qcelp_rate_octave_bitmap),
FF_ARRAY_ELEMS(qcelp_rate_quarter_bitmap),
qcelp_lspvq5
};
+/**
+ * the final gain scalefactor before clipping into a usable output float
+ */
+#define QCELP_SCALE 8192.
+
+/**
+ * the upper boundary of the clipping, depends on QCELP_SCALE
+ */
+#define QCELP_CLIP_UPPER_BOUND (8191.75/8192.)
+
+/**
+ * the lower boundary of the clipping, depends on QCELP_SCALE
+ */
+#define QCELP_CLIP_LOWER_BOUND -1.
+
+/**
+ * table for computing Ga (decoded linear codebook gain magnitude)
+ *
+ * @note The table could fit in int16_t in x*8 form, but it seems
+ * to be slower on x86
+ *
+ * TIA/EIA/IS-733 2.4.6.2.1-3
+ */
+
+static const float qcelp_g12ga[61] = {
+ 1.000/QCELP_SCALE, 1.125/QCELP_SCALE, 1.250/QCELP_SCALE, 1.375/QCELP_SCALE,
+ 1.625/QCELP_SCALE, 1.750/QCELP_SCALE, 2.000/QCELP_SCALE, 2.250/QCELP_SCALE,
+ 2.500/QCELP_SCALE, 2.875/QCELP_SCALE, 3.125/QCELP_SCALE, 3.500/QCELP_SCALE,
+ 4.000/QCELP_SCALE, 4.500/QCELP_SCALE, 5.000/QCELP_SCALE, 5.625/QCELP_SCALE,
+ 6.250/QCELP_SCALE, 7.125/QCELP_SCALE, 8.000/QCELP_SCALE, 8.875/QCELP_SCALE,
+ 10.000/QCELP_SCALE, 11.250/QCELP_SCALE, 12.625/QCELP_SCALE, 14.125/QCELP_SCALE,
+ 15.875/QCELP_SCALE, 17.750/QCELP_SCALE, 20.000/QCELP_SCALE, 22.375/QCELP_SCALE,
+ 25.125/QCELP_SCALE, 28.125/QCELP_SCALE, 31.625/QCELP_SCALE, 35.500/QCELP_SCALE,
+ 39.750/QCELP_SCALE, 44.625/QCELP_SCALE, 50.125/QCELP_SCALE, 56.250/QCELP_SCALE,
+ 63.125/QCELP_SCALE, 70.750/QCELP_SCALE, 79.375/QCELP_SCALE, 89.125/QCELP_SCALE,
+ 100.000/QCELP_SCALE, 112.250/QCELP_SCALE, 125.875/QCELP_SCALE, 141.250/QCELP_SCALE,
+ 158.500/QCELP_SCALE, 177.875/QCELP_SCALE, 199.500/QCELP_SCALE, 223.875/QCELP_SCALE,
+ 251.250/QCELP_SCALE, 281.875/QCELP_SCALE, 316.250/QCELP_SCALE, 354.875/QCELP_SCALE,
+ 398.125/QCELP_SCALE, 446.625/QCELP_SCALE, 501.125/QCELP_SCALE, 562.375/QCELP_SCALE,
+ 631.000/QCELP_SCALE, 708.000/QCELP_SCALE, 794.375/QCELP_SCALE, 891.250/QCELP_SCALE,
+ 1000.000/QCELP_SCALE};
+
/**
* circular codebook for rate 1 frames in x*100 form
*
};
#define QCELP_RATE_HALF_CODEBOOK_RATIO 0.5
+/**
+ * sqrt(1.887) is the maximum of the pseudorandom
+ * white sequence used to generate the scaled codebook
+ * vector for bitrate 1/4.
+ *
+ * TIA/EIA/IS-733 2.4.8.1.2
+ */
+#define QCELP_SQRT1887 1.373681186
+
+/**
+ * table for impulse response of BPF used to filter
+ * the white excitation for bitrate 1/4 synthesis
+ *
+ * Only half the tables are needed because of symmetry.
+ *
+ * TIA/EIA/IS-733 2.4.8.1.2-1.1
+ */
+static const double qcelp_rnd_fir_coefs[11] = {
+ -1.344519e-1, 1.735384e-2, -6.905826e-2, 2.434368e-2,
+ -8.210701e-2, 3.041388e-2, -9.251384e-2, 3.501983e-2,
+ -9.918777e-2, 3.749518e-2, 8.985137e-1
+};
+
+/**
+ * This spread factor is used, for bitrate 1/8 and I_F_Q,
+ * to force the LSP frequencies to be at least 80 Hz apart.
+ *
+ * TIA/EIA/IS-733 2.4.3.3.2
+ */
+#define QCELP_LSP_SPREAD_FACTOR 0.02
+
+/**
+ * predictor coefficient for the conversion of LSP codes
+ * to LSP frequencies for 1/8 and I_F_Q
+ *
+ * TIA/EIA/IS-733 2.4.3.2.7-2
+ */
+#define QCELP_LSP_OCTAVE_PREDICTOR 29.0/32
+
+/**
+ * initial coefficient to perform bandwidth expansion on LPC
+ *
+ * @note: 0.9883 looks like an approximation of 253/256.
+ *
+ * TIA/EIA/IS-733 2.4.3.3.6 6
+ */
+#define QCELP_BANDWIDTH_EXPANSION_COEFF 0.9883
+
#endif /* AVCODEC_QCELPDATA_H */
projects / frescor / ffmpeg.git / blobdiff