twinvq: Split VQF-specific part from common TwinVQ decoder core

Signed-off-by: Diego Biurrun <diego@biurrun.de>

1 files changed, 198 insertions, 0 deletions

diff --git a/libavcodec/twinvq.h b/libavcodec/twinvq.h
new file mode 100644
index 0000000000..d3a548a9f9
--- /dev/null
+++ b/libavcodec/twinvq.h
@@ -0,0 +1,198 @@
+/*
+ * TwinVQ decoder
+ * Copyright (c) 2009 Vitor Sessak
+ *
+ * This file is part of Libav.
+ *
+ * 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.
+ *
+ * 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVCODEC_TWINVQ_H
+#define AVCODEC_TWINVQ_H
+
+#include <math.h>
+#include <stdint.h>
+
+#include "libavutil/common.h"
+#include "libavutil/float_dsp.h"
+#include "avcodec.h"
+#include "fft.h"
+#include "internal.h"
+
+enum TwinVQCodec {
+    TWINVQ_CODEC_VQF,
+    TWINVQ_CODEC_METASOUND,
+};
+
+enum TwinVQFrameType {
+    TWINVQ_FT_SHORT = 0,  ///< Short frame  (divided in n   sub-blocks)
+    TWINVQ_FT_MEDIUM,     ///< Medium frame (divided in m<n sub-blocks)
+    TWINVQ_FT_LONG,       ///< Long frame   (single sub-block + PPC)
+    TWINVQ_FT_PPC,        ///< Periodic Peak Component (part of the long frame)
+};
+
+#define TWINVQ_PPC_SHAPE_CB_SIZE 64
+#define TWINVQ_PPC_SHAPE_LEN_MAX 60
+#define TWINVQ_SUB_AMP_MAX       4500.0
+#define TWINVQ_MULAW_MU          100.0
+#define TWINVQ_GAIN_BITS         8
+#define TWINVQ_AMP_MAX           13000.0
+#define TWINVQ_SUB_GAIN_BITS     5
+#define TWINVQ_WINDOW_TYPE_BITS  4
+#define TWINVQ_PGAIN_MU          200
+#define TWINVQ_LSP_COEFS_MAX     20
+#define TWINVQ_LSP_SPLIT_MAX     4
+#define TWINVQ_CHANNELS_MAX      2
+#define TWINVQ_SUBBLOCKS_MAX     16
+#define TWINVQ_BARK_N_COEF_MAX   4
+
+/**
+ * Parameters and tables that are different for each frame type
+ */
+struct TwinVQFrameMode {
+    uint8_t         sub;      ///< Number subblocks in each frame
+    const uint16_t *bark_tab;
+
+    /** number of distinct bark scale envelope values */
+    uint8_t         bark_env_size;
+
+    const int16_t  *bark_cb;    ///< codebook for the bark scale envelope (BSE)
+    uint8_t         bark_n_coef;///< number of BSE CB coefficients to read
+    uint8_t         bark_n_bit; ///< number of bits of the BSE coefs
+
+    //@{
+    /** main codebooks for spectrum data */
+    const int16_t    *cb0;
+    const int16_t    *cb1;
+    //@}
+
+    uint8_t         cb_len_read; ///< number of spectrum coefficients to read
+};
+
+typedef struct TwinVQFrameData {
+    int     window_type;
+    enum TwinVQFrameType ftype;
+
+    uint8_t main_coeffs[1024];
+    uint8_t ppc_coeffs[TWINVQ_PPC_SHAPE_LEN_MAX];
+
+    uint8_t gain_bits[TWINVQ_CHANNELS_MAX];
+    uint8_t sub_gain_bits[TWINVQ_CHANNELS_MAX * TWINVQ_SUBBLOCKS_MAX];
+
+    uint8_t bark1[TWINVQ_CHANNELS_MAX][TWINVQ_SUBBLOCKS_MAX][TWINVQ_BARK_N_COEF_MAX];
+    uint8_t bark_use_hist[TWINVQ_CHANNELS_MAX][TWINVQ_SUBBLOCKS_MAX];
+
+    uint8_t lpc_idx1[TWINVQ_CHANNELS_MAX];
+    uint8_t lpc_idx2[TWINVQ_CHANNELS_MAX][TWINVQ_LSP_SPLIT_MAX];
+    uint8_t lpc_hist_idx[TWINVQ_CHANNELS_MAX];
+
+    int     p_coef[TWINVQ_CHANNELS_MAX];
+    int     g_coef[TWINVQ_CHANNELS_MAX];
+} TwinVQFrameData;
+
+/**
+ * Parameters and tables that are different for every combination of
+ * bitrate/sample rate
+ */
+typedef struct TwinVQModeTab {
+    struct TwinVQFrameMode fmode[3]; ///< frame type-dependant parameters
+
+    uint16_t     size;        ///< frame size in samples
+    uint8_t      n_lsp;       ///< number of lsp coefficients
+    const float *lspcodebook;
+
+    /* number of bits of the different LSP CB coefficients */
+    uint8_t      lsp_bit0;
+    uint8_t      lsp_bit1;
+    uint8_t      lsp_bit2;
+
+    uint8_t      lsp_split;      ///< number of CB entries for the LSP decoding
+    const int16_t *ppc_shape_cb; ///< PPC shape CB
+
+    /** number of the bits for the PPC period value */
+    uint8_t      ppc_period_bit;
+
+    uint8_t      ppc_shape_bit;  ///< number of bits of the PPC shape CB coeffs
+    uint8_t      ppc_shape_len;  ///< size of PPC shape CB
+    uint8_t      pgain_bit;      ///< bits for PPC gain
+
+    /** constant for peak period to peak width conversion */
+    uint16_t     peak_per2wid;
+} TwinVQModeTab;
+
+typedef struct TwinVQContext {
+    AVCodecContext *avctx;
+    AVFloatDSPContext fdsp;
+    FFTContext mdct_ctx[3];
+
+    const TwinVQModeTab *mtab;
+
+    // history
+    float lsp_hist[2][20];           ///< LSP coefficients of the last frame
+    float bark_hist[3][2][40];       ///< BSE coefficients of last frame
+
+    // bitstream parameters
+    int16_t permut[4][4096];
+    uint8_t length[4][2];            ///< main codebook stride
+    uint8_t length_change[4];
+    uint8_t bits_main_spec[2][4][2]; ///< bits for the main codebook
+    int bits_main_spec_change[4];
+    int n_div[4];
+
+    float *spectrum;
+    float *curr_frame;               ///< non-interleaved output
+    float *prev_frame;               ///< non-interleaved previous frame
+    int last_block_pos[2];
+    int discarded_packets;
+
+    float *cos_tabs[3];
+
+    // scratch buffers
+    float *tmp_buf;
+
+    TwinVQFrameData bits;
+
+    enum TwinVQCodec codec;
+
+    int (*read_bitstream)(AVCodecContext *avctx, struct TwinVQContext *tctx,
+                          const uint8_t *buf, int buf_size);
+    void (*dec_bark_env)(struct TwinVQContext *tctx, const uint8_t *in,
+                         int use_hist, int ch, float *out, float gain,
+                         enum TwinVQFrameType ftype);
+    void (*decode_ppc)(struct TwinVQContext *tctx, int period_coef, int g_coef,
+                       const float *shape, float *speech);
+} TwinVQContext;
+
+extern const enum TwinVQFrameType ff_twinvq_wtype_to_ftype_table[];
+
+/** @note not speed critical, hence not optimized */
+static inline void twinvq_memset_float(float *buf, float val, int size)
+{
+    while (size--)
+        *buf++ = val;
+}
+
+static inline float twinvq_mulawinv(float y, float clip, float mu)
+{
+    y = av_clipf(y / clip, -1, 1);
+    return clip * FFSIGN(y) * (exp(log(1 + mu) * fabs(y)) - 1) / mu;
+}
+
+int ff_twinvq_decode_frame(AVCodecContext *avctx, void *data,
+                           int *got_frame_ptr, AVPacket *avpkt);
+av_cold int ff_twinvq_decode_close(AVCodecContext *avctx);
+av_cold int ff_twinvq_decode_init(AVCodecContext *avctx);
+
+#endif /* AVCODEC_TWINVQ_DATA_H */