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/*
* Copyright (c) 2012 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
*/
/**
* @file
* Common header for Microsoft Screen 1 and 2
*/
#ifndef AVCODEC_MSS12_H
#define AVCODEC_MSS12_H
#include "avcodec.h"
#include "get_bits.h"
#define MODEL_MIN_SYMS 2
#define MODEL_MAX_SYMS 256
#define THRESH_ADAPTIVE -1
#define THRESH_LOW 15
#define THRESH_HIGH 50
typedef struct Model {
int cum_prob[MODEL_MAX_SYMS + 1];
int weights[MODEL_MAX_SYMS + 1];
int idx2sym[MODEL_MAX_SYMS + 1];
int sym2idx[MODEL_MAX_SYMS + 1];
int num_syms;
int thr_weight, threshold;
} Model;
typedef struct ArithCoder {
int low, high, value;
GetBitContext *gb;
int (*get_model_sym)(struct ArithCoder *c, Model *m);
int (*get_number) (struct ArithCoder *c, int n);
} ArithCoder;
typedef struct PixContext {
int cache_size, num_syms;
uint8_t cache[12];
Model cache_model, full_model;
Model sec_models[4][8][4];
} PixContext;
typedef struct MSS12Context {
AVCodecContext *avctx;
uint8_t *pic_start;
int pic_stride;
uint8_t *mask;
int mask_linesize;
uint32_t pal[256];
int free_colours;
int keyframe;
Model intra_region, inter_region;
Model pivot, edge_mode, split_mode;
PixContext intra_pix_ctx, inter_pix_ctx;
int corrupted;
} MSS12Context;
int ff_mss12_decode_rect(MSS12Context *ctx, ArithCoder *acoder,
int x, int y, int width, int height);
void ff_mss12_model_update(Model *m, int val);
void ff_mss12_codec_reset(MSS12Context *ctx);
av_cold int ff_mss12_decode_init(AVCodecContext *avctx, int version);
av_cold int ff_mss12_decode_end(AVCodecContext *avctx);
#endif /* AVCODEC_MSS12_H */
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