You've already forked FFmpeg
mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2025-11-23 21:54:53 +02:00
81 lines
2.3 KiB
C
81 lines
2.3 KiB
C
|
/*
|
||
|
|
* 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_APV_DECODE_H
|
||
|
|
#define AVCODEC_APV_DECODE_H
|
||
|
|
|
||
|
|
#include <stdint.h>
|
||
|
|
|
||
|
|
#include "apv.h"
|
||
|
|
#include "avcodec.h"
|
||
|
|
#include "get_bits.h"
|
||
|
|
|
||
|
|
|
||
|
|
// Number of bits in the entropy look-up tables.
|
||
|
|
// It may be desirable to tune this per-architecture, as a larger LUT
|
||
|
|
// trades greater memory use for fewer instructions.
|
||
|
|
// (N bits -> 24*2^N bytes of tables; 9 -> 12KB of tables.)
|
||
|
|
#define APV_VLC_LUT_BITS 9
|
||
|
|
#define APV_VLC_LUT_SIZE (1 << APV_VLC_LUT_BITS)
|
||
|
|
|
||
|
|
typedef struct APVVLCLUTEntry {
|
||
|
|
uint16_t result; // Return value if not reading more.
|
||
|
|
uint8_t consume; // Number of bits to consume.
|
||
|
|
uint8_t more; // Whether to read additional bits.
|
||
|
|
} APVVLCLUTEntry;
|
||
|
|
|
||
|
|
typedef struct APVVLCLUT {
|
||
|
|
APVVLCLUTEntry lut[6][APV_VLC_LUT_SIZE];
|
||
|
|
} APVVLCLUT;
|
||
|
|
|
||
|
|
typedef struct APVEntropyState {
|
||
|
|
void *log_ctx;
|
||
|
|
|
||
|
|
const APVVLCLUT *decode_lut;
|
||
|
|
|
||
|
|
int16_t prev_dc;
|
||
|
|
int16_t prev_dc_diff;
|
||
|
|
int16_t prev_1st_ac_level;
|
||
|
|
} APVEntropyState;
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Build the decoder VLC look-up table.
|
||
|
|
*/
|
||
|
|
void ff_apv_entropy_build_decode_lut(APVVLCLUT *decode_lut);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Entropy decode a single 8x8 block to coefficients.
|
||
|
|
*
|
||
|
|
* Outputs in block order (dezigzag already applied).
|
||
|
|
*/
|
||
|
|
int ff_apv_entropy_decode_block(int16_t *coeff,
|
||
|
|
GetBitContext *gbc,
|
||
|
|
APVEntropyState *state);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Read a single APV VLC code.
|
||
|
|
*
|
||
|
|
* This entrypoint is exposed for testing.
|
||
|
|
*/
|
||
|
|
unsigned int ff_apv_read_vlc(GetBitContext *gbc, int k_param,
|
||
|
|
const APVVLCLUT *lut);
|
||
|
|
|
||
|
|
|
||
|
|
#endif /* AVCODEC_APV_DECODE_H */
|