ffmpeg/libavcodec/wavpack.h
Andreas Rheinhardt 483c85e85e avcodec/wavpack: Optimize always-false comparison away
Also use the correct type limit SIZE_MAX; INT_MAX comes
from a time when this used av_buffer_allocz() which used
an int at the time.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2024-04-19 13:18:04 +02:00

168 lines
4.3 KiB
C

/*
* 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 <limits.h>
#include <stdint.h>
#include "libavutil/attributes.h"
#include "libavutil/intmath.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_DSD_DATA 0x80000000
#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_CHANNELS (1 << 12)
#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_DSD_DATA,
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
extern const uint8_t ff_wp_exp2_table[256];
extern const uint8_t ff_wp_log2_table[256];
static av_always_inline int wp_exp2(int16_t val)
{
int res, neg = 0;
if (val < 0) {
val = -val;
neg = 1;
}
res = ff_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) + ff_wp_log2_table[(val << (9 - bits)) & 0xFF];
else
return (bits << 8) + ff_wp_log2_table[(val >> (bits - 9)) & 0xFF];
}
#endif /* AVCODEC_WAVPACK_H */