FFmpeg/libavcodec/wavpack.h

/*
 * WavPack decoder/encoder common code
 * Copyright (c) 2006,2011 Konstantin Shishkov
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg 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,
 * 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
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifndef AVCODEC_WAVPACK_H
#define AVCODEC_WAVPACK_H

#include "libavutil/common.h"

#define MAX_TERMS      16
#define MAX_TERM        8

#define WV_HEADER_SIZE    32

#define WV_MONO           0x00000004
#define WV_JOINT_STEREO   0x00000010
#define WV_CROSS_DECORR   0x00000020
#define WV_FLOAT_DATA     0x00000080
#define WV_INT32_DATA     0x00000100
#define WV_FALSE_STEREO   0x40000000

#define WV_HYBRID_MODE    0x00000008
#define WV_HYBRID_SHAPE   0x00000008
#define WV_HYBRID_BITRATE 0x00000200
#define WV_HYBRID_BALANCE 0x00000400
#define WV_INITIAL_BLOCK  0x00000800
#define WV_FINAL_BLOCK    0x00001000

#define WV_MONO_DATA    (WV_MONO | WV_FALSE_STEREO)

#define WV_SINGLE_BLOCK (WV_INITIAL_BLOCK | WV_FINAL_BLOCK)

#define WV_FLT_SHIFT_ONES 0x01
#define WV_FLT_SHIFT_SAME 0x02
#define WV_FLT_SHIFT_SENT 0x04
#define WV_FLT_ZERO_SENT  0x08
#define WV_FLT_ZERO_SIGN  0x10

#define WV_MAX_SAMPLES    150000

enum WP_ID_Flags {
    WP_IDF_MASK   = 0x3F,
    WP_IDF_IGNORE = 0x20,
    WP_IDF_ODD    = 0x40,
    WP_IDF_LONG   = 0x80
};

enum WP_ID {
    WP_ID_DUMMY = 0,
    WP_ID_ENCINFO,
    WP_ID_DECTERMS,
    WP_ID_DECWEIGHTS,
    WP_ID_DECSAMPLES,
    WP_ID_ENTROPY,
    WP_ID_HYBRID,
    WP_ID_SHAPING,
    WP_ID_FLOATINFO,
    WP_ID_INT32INFO,
    WP_ID_DATA,
    WP_ID_CORR,
    WP_ID_EXTRABITS,
    WP_ID_CHANINFO,
    WP_ID_SAMPLE_RATE = 0x27,
};

typedef struct Decorr {
    int delta;
    int value;
    int weightA;
    int weightB;
    int samplesA[MAX_TERM];
    int samplesB[MAX_TERM];
    int sumA;
    int sumB;
} Decorr;

typedef struct WvChannel {
    int median[3];
    int slow_level, error_limit;
    unsigned bitrate_acc, bitrate_delta;
} WvChannel;

// macros for manipulating median values
#define GET_MED(n) ((c->median[n] >> 4) + 1)
#define DEC_MED(n) c->median[n] -= ((int)(c->median[n] + (128U >> (n)) - 2) / (128 >> (n))) * 2U
#define INC_MED(n) c->median[n] += ((int)(c->median[n] + (128U >> (n))    ) / (128 >> (n))) * 5U

// macros for applying weight
#define UPDATE_WEIGHT_CLIP(weight, delta, samples, in) \
    if ((samples) && (in)) { \
        if (((samples) ^ (in)) < 0) { \
            (weight) -= (delta); \
            if ((weight) < -1024) \
                (weight) = -1024; \
        } else { \
            (weight) += (delta); \
            if ((weight) > 1024) \
                (weight) = 1024; \
        } \
    }

static const int wv_rates[16] = {
     6000,  8000,  9600, 11025, 12000, 16000,  22050, 24000,
    32000, 44100, 48000, 64000, 88200, 96000, 192000,     0
};

// exponent table copied from WavPack source
static const uint8_t wp_exp2_table[256] = {
    0x00, 0x01, 0x01, 0x02, 0x03, 0x03, 0x04, 0x05, 0x06, 0x06, 0x07, 0x08, 0x08, 0x09, 0x0a, 0x0b,
    0x0b, 0x0c, 0x0d, 0x0e, 0x0e, 0x0f, 0x10, 0x10, 0x11, 0x12, 0x13, 0x13, 0x14, 0x15, 0x16, 0x16,
    0x17, 0x18, 0x19, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1d, 0x1e, 0x1f, 0x20, 0x20, 0x21, 0x22, 0x23,
    0x24, 0x24, 0x25, 0x26, 0x27, 0x28, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2c, 0x2d, 0x2e, 0x2f, 0x30,
    0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3a, 0x3b, 0x3c, 0x3d,
    0x3e, 0x3f, 0x40, 0x41, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x48, 0x49, 0x4a, 0x4b,
    0x4c, 0x4d, 0x4e, 0x4f, 0x50, 0x51, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a,
    0x5b, 0x5c, 0x5d, 0x5e, 0x5e, 0x5f, 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,
    0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79,
    0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x87, 0x88, 0x89, 0x8a,
    0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0x90, 0x91, 0x92, 0x93, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0x9b,
    0x9c, 0x9d, 0x9f, 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad,
    0xaf, 0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xbc, 0xbd, 0xbe, 0xbf, 0xc0,
    0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc8, 0xc9, 0xca, 0xcb, 0xcd, 0xce, 0xcf, 0xd0, 0xd2, 0xd3, 0xd4,
    0xd6, 0xd7, 0xd8, 0xd9, 0xdb, 0xdc, 0xdd, 0xde, 0xe0, 0xe1, 0xe2, 0xe4, 0xe5, 0xe6, 0xe8, 0xe9,
    0xea, 0xec, 0xed, 0xee, 0xf0, 0xf1, 0xf2, 0xf4, 0xf5, 0xf6, 0xf8, 0xf9, 0xfa, 0xfc, 0xfd, 0xff
};

static const uint8_t wp_log2_table [] = {
    0x00, 0x01, 0x03, 0x04, 0x06, 0x07, 0x09, 0x0a, 0x0b, 0x0d, 0x0e, 0x10, 0x11, 0x12, 0x14, 0x15,
    0x16, 0x18, 0x19, 0x1a, 0x1c, 0x1d, 0x1e, 0x20, 0x21, 0x22, 0x24, 0x25, 0x26, 0x28, 0x29, 0x2a,
    0x2c, 0x2d, 0x2e, 0x2f, 0x31, 0x32, 0x33, 0x34, 0x36, 0x37, 0x38, 0x39, 0x3b, 0x3c, 0x3d, 0x3e,
    0x3f, 0x41, 0x42, 0x43, 0x44, 0x45, 0x47, 0x48, 0x49, 0x4a, 0x4b, 0x4d, 0x4e, 0x4f, 0x50, 0x51,
    0x52, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 0x5c, 0x5d, 0x5e, 0x5f, 0x60, 0x61, 0x62, 0x63,
    0x64, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72, 0x74, 0x75,
    0x76, 0x77, 0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85,
    0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0x90, 0x91, 0x92, 0x93, 0x94, 0x95,
    0x96, 0x97, 0x98, 0x99, 0x9a, 0x9b, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, 0xa0, 0xa1, 0xa2, 0xa3, 0xa4,
    0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, 0xb0, 0xb1, 0xb2, 0xb2,
    0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, 0xc0, 0xc0,
    0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xcb, 0xcb, 0xcc, 0xcd, 0xce,
    0xcf, 0xd0, 0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd8, 0xd9, 0xda, 0xdb,
    0xdc, 0xdc, 0xdd, 0xde, 0xdf, 0xe0, 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe4, 0xe5, 0xe6, 0xe7, 0xe7,
    0xe8, 0xe9, 0xea, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xee, 0xef, 0xf0, 0xf1, 0xf1, 0xf2, 0xf3, 0xf4,
    0xf4, 0xf5, 0xf6, 0xf7, 0xf7, 0xf8, 0xf9, 0xf9, 0xfa, 0xfb, 0xfc, 0xfc, 0xfd, 0xfe, 0xff, 0xff
};

static av_always_inline int wp_exp2(int16_t val)
{
    int res, neg = 0;

    if (val < 0) {
        val = -val;
        neg = 1;
    }

    res   = wp_exp2_table[val & 0xFF] | 0x100;
    val >>= 8;
    if (val > 31U)
        return INT_MIN;
    res   = (val > 9) ? (res << (val - 9)) : (res >> (9 - val));
    return neg ? -res : res;
}

static av_always_inline int wp_log2(uint32_t val)
{
    int bits;

    if (!val)
        return 0;
    if (val == 1)
        return 256;
    val += val >> 9;
    bits = av_log2(val) + 1;
    if (bits < 9)
        return (bits << 8) + wp_log2_table[(val << (9 - bits)) & 0xFF];
    else
        return (bits << 8) + wp_log2_table[(val >> (bits - 9)) & 0xFF];
}

#endif /* AVCODEC_WAVPACK_H */