* QCELP decoder
* Copyright (c) 2007 Reynaldo H. Verdejo Pinochet
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
- * FFmpeg is distributed in the hope that it will be useful,
+ * Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#define AVCODEC_QCELPDATA_H
/**
- * @file qcelpdata.h
+ * @file
* Data tables for the QCELP decoder
* @author Reynaldo H. Verdejo Pinochet
+ * @remark Libav 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 QCELPFrame {
+/// @name 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
+/// @}
+
+/// @name 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
*/
static const float qcelp_hammsinc_table[4] = { -0.006822, 0.041249, -0.143459, 0.588863};
-typedef struct {
- uint8_t index; /*!< index into the QCELPContext structure */
- uint8_t bitpos; /*!< position of the lowest bit in the value's byte */
- uint8_t bitlen; /*!< number of bits to read */
+typedef struct QCELPBitmap {
+ uint8_t index; /**< index into the QCELPContext structure */
+ uint8_t bitpos; /**< position of the lowest bit in the value's byte */
+ 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
* the QCELPContext
*/
static const QCELPBitmap * const qcelp_unpacking_bitmaps_per_rate[5] = {
- NULL, ///!< for SILENCE rate
+ NULL, ///< for SILENCE rate
qcelp_rate_octave_bitmap,
qcelp_rate_quarter_bitmap,
qcelp_rate_half_bitmap,
qcelp_rate_full_bitmap,
};
-static const uint16_t qcelp_bits_per_rate[5] = {
- 0, ///!< for SILENCE rate
+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),
FF_ARRAY_ELEMS(qcelp_rate_half_bitmap),
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, 563.375/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};
/**
* sqrt(1.887) is the maximum of the pseudorandom
* white sequence used to generate the scaled codebook
- * vector for framerate 1/4.
+ * vector for bitrate 1/4.
*
* TIA/EIA/IS-733 2.4.8.1.2
*/
/**
* table for impulse response of BPF used to filter
- * the white excitation for framerate 1/4 synthesis
+ * the white excitation for bitrate 1/4 synthesis
*
- * Only half the tables are needed because of symetry.
+ * Only half the tables are needed because of symmetry.
*
* TIA/EIA/IS-733 2.4.8.1.2-1.1
*/
-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 / ffmpeg / blobdiff