mirror of
https://github.com/FFmpeg/FFmpeg.git
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852 lines
23 KiB
C
852 lines
23 KiB
C
/*
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* Microsoft Screen 1 (aka Windows Media Video V7 Screen) decoder
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* Copyright (c) 2012 Konstantin Shishkov
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*
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* This file is part of Libav.
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*
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* Libav is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* Libav is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with Libav; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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/**
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* @file
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* Microsoft Screen 1 (aka Windows Media Video V7 Screen) decoder
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*/
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#include "libavutil/intfloat.h"
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#include "libavutil/intreadwrite.h"
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#include "avcodec.h"
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#include "get_bits.h"
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enum SplitMode {
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SPLIT_VERT = 0,
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SPLIT_HOR,
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SPLIT_NONE
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};
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typedef struct ArithCoder {
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int low, high, value;
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GetBitContext *gb;
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} ArithCoder;
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#define MODEL_MIN_SYMS 2
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#define MODEL_MAX_SYMS 256
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#define THRESH_ADAPTIVE -1
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#define THRESH_LOW 15
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#define THRESH_HIGH 50
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typedef struct Model {
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int cum_prob[MODEL_MAX_SYMS + 1];
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int weights[MODEL_MAX_SYMS + 1];
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int idx2sym[MODEL_MAX_SYMS + 1];
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int sym2idx[MODEL_MAX_SYMS + 1];
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int num_syms;
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int thr_weight, threshold;
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} Model;
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static const int sec_order_sizes[4] = { 1, 7, 6, 1 };
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enum ContextDirection {
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TOP_LEFT = 0,
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TOP,
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TOP_RIGHT,
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LEFT
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};
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typedef struct PixContext {
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int cache_size, num_syms;
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uint8_t cache[12];
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Model cache_model, full_model;
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Model sec_models[4][8][4];
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} PixContext;
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typedef struct MSS1Context {
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AVCodecContext *avctx;
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AVFrame pic;
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uint8_t *pic_start;
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int pic_stride;
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uint8_t *mask;
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int mask_linesize;
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uint32_t pal[256];
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int free_colours;
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Model intra_region, inter_region;
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Model pivot, edge_mode, split_mode;
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PixContext intra_pix_ctx, inter_pix_ctx;
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int corrupted;
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} MSS1Context;
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static void arith_init(ArithCoder *c, GetBitContext *gb)
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{
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c->low = 0;
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c->high = 0xFFFF;
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c->value = get_bits(gb, 16);
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c->gb = gb;
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}
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static void arith_normalise(ArithCoder *c)
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{
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for (;;) {
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if (c->high >= 0x8000) {
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if (c->low < 0x8000) {
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if (c->low >= 0x4000 && c->high < 0xC000) {
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c->value -= 0x4000;
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c->low -= 0x4000;
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c->high -= 0x4000;
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} else {
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return;
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}
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} else {
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c->value -= 0x8000;
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c->low -= 0x8000;
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c->high -= 0x8000;
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}
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}
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c->value <<= 1;
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c->low <<= 1;
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c->high <<= 1;
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c->high |= 1;
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c->value |= get_bits1(c->gb);
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}
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}
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static int arith_get_bit(ArithCoder *c)
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{
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int range = c->high - c->low + 1;
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int bit = (((c->value - c->low) << 1) + 1) / range;
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if (bit)
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c->low += range >> 1;
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else
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c->high = c->low + (range >> 1) - 1;
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arith_normalise(c);
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return bit;
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}
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static int arith_get_bits(ArithCoder *c, int bits)
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{
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int range = c->high - c->low + 1;
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int val = (((c->value - c->low + 1) << bits) - 1) / range;
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int prob = range * val;
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c->high = ((prob + range) >> bits) + c->low - 1;
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c->low += prob >> bits;
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arith_normalise(c);
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return val;
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}
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static int arith_get_number(ArithCoder *c, int mod_val)
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{
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int range = c->high - c->low + 1;
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int val = ((c->value - c->low + 1) * mod_val - 1) / range;
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int prob = range * val;
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c->high = (prob + range) / mod_val + c->low - 1;
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c->low += prob / mod_val;
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arith_normalise(c);
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return val;
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}
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static int arith_get_prob(ArithCoder *c, int *probs)
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{
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int range = c->high - c->low + 1;
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int val = ((c->value - c->low + 1) * probs[0] - 1) / range;
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int sym = 1;
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while (probs[sym] > val)
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sym++;
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c->high = range * probs[sym - 1] / probs[0] + c->low - 1;
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c->low += range * probs[sym] / probs[0];
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return sym;
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}
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static int model_calc_threshold(Model *m)
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{
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int thr;
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if (m->thr_weight == -1) {
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thr = 2 * m->weights[m->num_syms] - 1;
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thr = ((thr >> 1) + 4 * m->cum_prob[0]) / thr;
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} else {
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thr = m->num_syms * m->thr_weight;
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}
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return FFMIN(thr, 0x3FFF);
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}
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static void model_reset(Model *m)
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{
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int i;
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for (i = 0; i <= m->num_syms; i++) {
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m->weights[i] = 1;
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m->cum_prob[i] = m->num_syms - i;
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}
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m->weights[0] = -1;
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m->idx2sym[0] = -1;
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m->sym2idx[m->num_syms] = -1;
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for (i = 0; i < m->num_syms; i++) {
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m->sym2idx[i] = i + 1;
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m->idx2sym[i + 1] = i;
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}
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}
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static av_cold void model_init(Model *m, int num_syms, int thr_weight)
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{
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m->num_syms = num_syms;
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m->thr_weight = thr_weight;
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m->threshold = model_calc_threshold(m);
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model_reset(m);
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}
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static void model_rescale_weights(Model *m)
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{
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int i;
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int cum_prob;
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if (m->thr_weight == -1)
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m->threshold = model_calc_threshold(m);
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while (m->cum_prob[0] > m->threshold) {
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cum_prob = 0;
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for (i = m->num_syms; i >= 0; i--) {
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m->cum_prob[i] = cum_prob;
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m->weights[i] = (m->weights[i] + 1) >> 1;
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cum_prob += m->weights[i];
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}
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}
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}
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static void model_update(Model *m, int val)
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{
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int i;
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if (m->weights[val] == m->weights[val - 1]) {
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for (i = val; m->weights[i - 1] == m->weights[val]; i--);
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if (i != val) {
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int sym1, sym2;
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sym1 = m->idx2sym[val];
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sym2 = m->idx2sym[i];
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m->idx2sym[val] = sym2;
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m->idx2sym[i] = sym1;
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m->sym2idx[sym1] = i;
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m->sym2idx[sym2] = val;
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val = i;
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}
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}
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m->weights[val]++;
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for (i = val - 1; i >= 0; i--)
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m->cum_prob[i]++;
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model_rescale_weights(m);
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}
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static int arith_get_model_sym(ArithCoder *c, Model *m)
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{
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int idx, val;
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idx = arith_get_prob(c, m->cum_prob);
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val = m->idx2sym[idx];
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model_update(m, idx);
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arith_normalise(c);
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return val;
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}
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static void pixctx_reset(PixContext *ctx)
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{
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int i, j, k;
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for (i = 0; i < ctx->cache_size; i++)
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ctx->cache[i] = i;
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model_reset(&ctx->cache_model);
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model_reset(&ctx->full_model);
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for (i = 0; i < 4; i++)
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for (j = 0; j < sec_order_sizes[i]; j++)
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for (k = 0; k < 4; k++)
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model_reset(&ctx->sec_models[i][j][k]);
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}
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static av_cold void pixctx_init(PixContext *ctx, int cache_size)
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{
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int i, j, k;
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ctx->cache_size = cache_size + 4;
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ctx->num_syms = cache_size;
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for (i = 0; i < ctx->cache_size; i++)
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ctx->cache[i] = i;
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model_init(&ctx->cache_model, ctx->num_syms + 1, THRESH_LOW);
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model_init(&ctx->full_model, 256, THRESH_HIGH);
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for (i = 0; i < 4; i++) {
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for (j = 0; j < sec_order_sizes[i]; j++) {
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for (k = 0; k < 4; k++) {
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model_init(&ctx->sec_models[i][j][k], 2 + i,
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i ? THRESH_LOW : THRESH_ADAPTIVE);
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}
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}
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}
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}
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static int decode_top_left_pixel(ArithCoder *acoder, PixContext *pctx)
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{
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int i, val, pix;
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val = arith_get_model_sym(acoder, &pctx->cache_model);
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if (val < pctx->num_syms) {
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pix = pctx->cache[val];
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} else {
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pix = arith_get_model_sym(acoder, &pctx->full_model);
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for (i = 0; i < pctx->cache_size - 1; i++)
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if (pctx->cache[i] == pix)
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break;
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val = i;
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}
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if (val) {
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for (i = val; i > 0; i--)
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pctx->cache[i] = pctx->cache[i - 1];
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pctx->cache[0] = pix;
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}
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return pix;
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}
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static int decode_pixel(ArithCoder *acoder, PixContext *pctx,
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uint8_t *ngb, int num_ngb)
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{
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int i, val, pix;
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val = arith_get_model_sym(acoder, &pctx->cache_model);
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if (val < pctx->num_syms) {
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int idx, j;
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idx = 0;
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for (i = 0; i < pctx->cache_size; i++) {
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for (j = 0; j < num_ngb; j++)
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if (pctx->cache[i] == ngb[j])
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break;
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if (j == num_ngb) {
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if (idx == val)
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break;
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idx++;
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}
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}
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val = FFMIN(i, pctx->cache_size - 1);
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pix = pctx->cache[val];
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} else {
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pix = arith_get_model_sym(acoder, &pctx->full_model);
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for (i = 0; i < pctx->cache_size - 1; i++)
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if (pctx->cache[i] == pix)
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break;
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val = i;
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}
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if (val) {
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for (i = val; i > 0; i--)
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pctx->cache[i] = pctx->cache[i - 1];
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pctx->cache[0] = pix;
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}
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return pix;
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}
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static int decode_pixel_in_context(ArithCoder *acoder, PixContext *pctx,
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uint8_t *src, int stride, int x, int y,
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int has_right)
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{
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uint8_t neighbours[4];
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uint8_t ref_pix[4];
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int nlen;
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int layer = 0, sub;
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int pix;
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int i, j;
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if (!y) {
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memset(neighbours, src[-1], 4);
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} else {
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neighbours[TOP] = src[-stride];
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if (!x) {
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neighbours[TOP_LEFT] = neighbours[LEFT] = neighbours[TOP];
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} else {
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neighbours[TOP_LEFT] = src[-stride - 1];
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neighbours[ LEFT] = src[-1];
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}
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if (has_right)
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neighbours[TOP_RIGHT] = src[-stride + 1];
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else
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neighbours[TOP_RIGHT] = neighbours[TOP];
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}
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sub = 0;
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if (x >= 2 && src[-2] == neighbours[LEFT])
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sub = 1;
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if (y >= 2 && src[-2 * stride] == neighbours[TOP])
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sub |= 2;
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nlen = 1;
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ref_pix[0] = neighbours[0];
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for (i = 1; i < 4; i++) {
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for (j = 0; j < nlen; j++)
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if (ref_pix[j] == neighbours[i])
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break;
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if (j == nlen)
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ref_pix[nlen++] = neighbours[i];
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}
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switch (nlen) {
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case 1:
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case 4:
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layer = 0;
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break;
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case 2:
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if (neighbours[TOP] == neighbours[TOP_LEFT]) {
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if (neighbours[TOP_RIGHT] == neighbours[TOP_LEFT])
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layer = 3;
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else if (neighbours[LEFT] == neighbours[TOP_LEFT])
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layer = 2;
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else
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layer = 4;
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} else if (neighbours[TOP_RIGHT] == neighbours[TOP_LEFT]) {
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if (neighbours[LEFT] == neighbours[TOP_LEFT])
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layer = 1;
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else
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layer = 5;
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} else if (neighbours[LEFT] == neighbours[TOP_LEFT]) {
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layer = 6;
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} else {
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layer = 0;
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}
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break;
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case 3:
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if (neighbours[TOP] == neighbours[TOP_LEFT])
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layer = 0;
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else if (neighbours[TOP_RIGHT] == neighbours[TOP_LEFT])
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layer = 1;
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else if (neighbours[LEFT] == neighbours[TOP_LEFT])
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layer = 2;
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else if (neighbours[TOP_RIGHT] == neighbours[TOP])
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layer = 3;
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else if (neighbours[TOP] == neighbours[LEFT])
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layer = 4;
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else
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layer = 5;
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break;
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}
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pix = arith_get_model_sym(acoder, &pctx->sec_models[nlen - 1][layer][sub]);
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if (pix < nlen)
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return ref_pix[pix];
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else
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return decode_pixel(acoder, pctx, ref_pix, nlen);
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}
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static int decode_region(MSS1Context *ctx, ArithCoder *acoder, uint8_t *dst,
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int x, int y, int width, int height, int stride,
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PixContext *pctx)
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{
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int i, j;
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dst += x + y * stride;
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dst[0] = decode_top_left_pixel(acoder, pctx);
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for (j = 0; j < height; j++) {
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for (i = 0; i < width; i++) {
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if (!i && !j)
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continue;
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dst[i] = decode_pixel_in_context(acoder, pctx, dst + i, stride,
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i, j, width - i - 1);
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}
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dst += stride;
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}
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return 0;
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}
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static int decode_region_masked(MSS1Context *ctx, ArithCoder *acoder,
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uint8_t *dst, int stride, uint8_t *mask,
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int mask_stride, int x, int y,
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int width, int height,
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PixContext *pctx)
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{
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int i, j;
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dst += x + y * stride;
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mask += x + y * mask_stride;
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if (mask[0] == 0xFF)
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dst[0] = decode_top_left_pixel(acoder, pctx);
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for (j = 0; j < height; j++) {
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for (i = 0; i < width; i++) {
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if (!i && !j || mask[i] != 0xFF)
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continue;
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dst[i] = decode_pixel_in_context(acoder, pctx, dst + i, stride,
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i, j, width - i - 1);
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}
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dst += stride;
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mask += mask_stride;
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}
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return 0;
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}
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static av_cold void codec_init(MSS1Context *ctx)
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{
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model_init(&ctx->intra_region, 2, THRESH_ADAPTIVE);
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model_init(&ctx->inter_region, 2, THRESH_ADAPTIVE);
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model_init(&ctx->split_mode, 3, THRESH_HIGH);
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model_init(&ctx->edge_mode, 2, THRESH_HIGH);
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model_init(&ctx->pivot, 3, THRESH_LOW);
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pixctx_init(&ctx->intra_pix_ctx, 8);
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pixctx_init(&ctx->inter_pix_ctx, 2);
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ctx->corrupted = 1;
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}
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static void codec_reset(MSS1Context *ctx)
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{
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model_reset(&ctx->intra_region);
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model_reset(&ctx->inter_region);
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|
model_reset(&ctx->split_mode);
|
|
model_reset(&ctx->edge_mode);
|
|
model_reset(&ctx->pivot);
|
|
pixctx_reset(&ctx->intra_pix_ctx);
|
|
pixctx_reset(&ctx->inter_pix_ctx);
|
|
|
|
ctx->corrupted = 0;
|
|
}
|
|
|
|
static int decode_pal(MSS1Context *ctx, ArithCoder *acoder)
|
|
{
|
|
int i, ncol, r, g, b;
|
|
uint32_t *pal = ctx->pal + 256 - ctx->free_colours;
|
|
|
|
if (!ctx->free_colours)
|
|
return 0;
|
|
|
|
ncol = arith_get_number(acoder, ctx->free_colours + 1);
|
|
for (i = 0; i < ncol; i++) {
|
|
r = arith_get_bits(acoder, 8);
|
|
g = arith_get_bits(acoder, 8);
|
|
b = arith_get_bits(acoder, 8);
|
|
*pal++ = (r << 16) | (g << 8) | b;
|
|
}
|
|
|
|
return !!ncol;
|
|
}
|
|
|
|
static int decode_pivot(MSS1Context *ctx, ArithCoder *acoder, int base)
|
|
{
|
|
int val, inv;
|
|
|
|
inv = arith_get_model_sym(acoder, &ctx->edge_mode);
|
|
val = arith_get_model_sym(acoder, &ctx->pivot) + 1;
|
|
|
|
if (val > 2) {
|
|
if ((base + 1) / 2 - 2 <= 0) {
|
|
ctx->corrupted = 1;
|
|
return 0;
|
|
}
|
|
val = arith_get_number(acoder, (base + 1) / 2 - 2) + 3;
|
|
}
|
|
|
|
if (val == base) {
|
|
ctx->corrupted = 1;
|
|
return 0;
|
|
}
|
|
|
|
return inv ? base - val : val;
|
|
}
|
|
|
|
static int decode_region_intra(MSS1Context *ctx, ArithCoder *acoder,
|
|
int x, int y, int width, int height)
|
|
{
|
|
int mode;
|
|
|
|
mode = arith_get_model_sym(acoder, &ctx->intra_region);
|
|
|
|
if (!mode) {
|
|
int i, pix;
|
|
int stride = ctx->pic_stride;
|
|
uint8_t *dst = ctx->pic_start + x + y * stride;
|
|
|
|
pix = decode_top_left_pixel(acoder, &ctx->intra_pix_ctx);
|
|
for (i = 0; i < height; i++, dst += stride)
|
|
memset(dst, pix, width);
|
|
} else {
|
|
return decode_region(ctx, acoder, ctx->pic_start,
|
|
x, y, width, height, ctx->pic_stride,
|
|
&ctx->intra_pix_ctx);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int decode_intra(MSS1Context *ctx, ArithCoder *acoder,
|
|
int x, int y, int width, int height)
|
|
{
|
|
int mode, pivot;
|
|
|
|
if (ctx->corrupted)
|
|
return -1;
|
|
|
|
mode = arith_get_model_sym(acoder, &ctx->split_mode);
|
|
|
|
switch (mode) {
|
|
case SPLIT_VERT:
|
|
pivot = decode_pivot(ctx, acoder, height);
|
|
if (ctx->corrupted)
|
|
return -1;
|
|
if (decode_intra(ctx, acoder, x, y, width, pivot))
|
|
return -1;
|
|
if (decode_intra(ctx, acoder, x, y + pivot, width, height - pivot))
|
|
return -1;
|
|
break;
|
|
case SPLIT_HOR:
|
|
pivot = decode_pivot(ctx, acoder, width);
|
|
if (ctx->corrupted)
|
|
return -1;
|
|
if (decode_intra(ctx, acoder, x, y, pivot, height))
|
|
return -1;
|
|
if (decode_intra(ctx, acoder, x + pivot, y, width - pivot, height))
|
|
return -1;
|
|
break;
|
|
case SPLIT_NONE:
|
|
return decode_region_intra(ctx, acoder, x, y, width, height);
|
|
default:
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int decode_region_inter(MSS1Context *ctx, ArithCoder *acoder,
|
|
int x, int y, int width, int height)
|
|
{
|
|
int mode;
|
|
|
|
mode = arith_get_model_sym(acoder, &ctx->inter_region);
|
|
|
|
if (!mode) {
|
|
mode = decode_top_left_pixel(acoder, &ctx->inter_pix_ctx);
|
|
if (mode != 0xFF) {
|
|
return 0;
|
|
} else {
|
|
return decode_region_intra(ctx, acoder, x, y, width, height);
|
|
}
|
|
} else {
|
|
if (decode_region(ctx, acoder, ctx->mask,
|
|
x, y, width, height, ctx->mask_linesize,
|
|
&ctx->inter_pix_ctx) < 0)
|
|
return -1;
|
|
return decode_region_masked(ctx, acoder, ctx->pic_start,
|
|
-ctx->pic.linesize[0], ctx->mask,
|
|
ctx->mask_linesize,
|
|
x, y, width, height,
|
|
&ctx->intra_pix_ctx);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int decode_inter(MSS1Context *ctx, ArithCoder *acoder,
|
|
int x, int y, int width, int height)
|
|
{
|
|
int mode, pivot;
|
|
|
|
if (ctx->corrupted)
|
|
return -1;
|
|
|
|
mode = arith_get_model_sym(acoder, &ctx->split_mode);
|
|
|
|
switch (mode) {
|
|
case SPLIT_VERT:
|
|
pivot = decode_pivot(ctx, acoder, height);
|
|
if (decode_inter(ctx, acoder, x, y, width, pivot))
|
|
return -1;
|
|
if (decode_inter(ctx, acoder, x, y + pivot, width, height - pivot))
|
|
return -1;
|
|
break;
|
|
case SPLIT_HOR:
|
|
pivot = decode_pivot(ctx, acoder, width);
|
|
if (decode_inter(ctx, acoder, x, y, pivot, height))
|
|
return -1;
|
|
if (decode_inter(ctx, acoder, x + pivot, y, width - pivot, height))
|
|
return -1;
|
|
break;
|
|
case SPLIT_NONE:
|
|
return decode_region_inter(ctx, acoder, x, y, width, height);
|
|
default:
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int mss1_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
|
|
AVPacket *avpkt)
|
|
{
|
|
const uint8_t *buf = avpkt->data;
|
|
int buf_size = avpkt->size;
|
|
MSS1Context *c = avctx->priv_data;
|
|
GetBitContext gb;
|
|
ArithCoder acoder;
|
|
int pal_changed = 0;
|
|
int ret;
|
|
|
|
init_get_bits(&gb, buf, buf_size * 8);
|
|
arith_init(&acoder, &gb);
|
|
|
|
c->pic.reference = 3;
|
|
c->pic.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE |
|
|
FF_BUFFER_HINTS_REUSABLE;
|
|
if ((ret = avctx->reget_buffer(avctx, &c->pic)) < 0) {
|
|
av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
|
|
return ret;
|
|
}
|
|
|
|
c->pic_start = c->pic.data[0] + c->pic.linesize[0] * (avctx->height - 1);
|
|
c->pic_stride = -c->pic.linesize[0];
|
|
if (!arith_get_bit(&acoder)) {
|
|
codec_reset(c);
|
|
pal_changed = decode_pal(c, &acoder);
|
|
c->corrupted = decode_intra(c, &acoder, 0, 0,
|
|
avctx->width, avctx->height);
|
|
c->pic.key_frame = 1;
|
|
c->pic.pict_type = AV_PICTURE_TYPE_I;
|
|
} else {
|
|
if (c->corrupted)
|
|
return AVERROR_INVALIDDATA;
|
|
c->corrupted = decode_inter(c, &acoder, 0, 0,
|
|
avctx->width, avctx->height);
|
|
c->pic.key_frame = 0;
|
|
c->pic.pict_type = AV_PICTURE_TYPE_P;
|
|
}
|
|
if (c->corrupted)
|
|
return AVERROR_INVALIDDATA;
|
|
memcpy(c->pic.data[1], c->pal, AVPALETTE_SIZE);
|
|
c->pic.palette_has_changed = pal_changed;
|
|
|
|
*data_size = sizeof(AVFrame);
|
|
*(AVFrame*)data = c->pic;
|
|
|
|
/* always report that the buffer was completely consumed */
|
|
return buf_size;
|
|
}
|
|
|
|
static av_cold int mss1_decode_init(AVCodecContext *avctx)
|
|
{
|
|
MSS1Context * const c = avctx->priv_data;
|
|
int i;
|
|
|
|
c->avctx = avctx;
|
|
|
|
if (avctx->extradata_size < 52 + 256 * 3) {
|
|
av_log(avctx, AV_LOG_ERROR, "Insufficient extradata size %d\n",
|
|
avctx->extradata_size);
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
if (AV_RB32(avctx->extradata) < avctx->extradata_size) {
|
|
av_log(avctx, AV_LOG_ERROR,
|
|
"Insufficient extradata size: expected %d got %d\n",
|
|
AV_RB32(avctx->extradata),
|
|
avctx->extradata_size);
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
av_log(avctx, AV_LOG_DEBUG, "Encoder version %d.%d\n",
|
|
AV_RB32(avctx->extradata + 4), AV_RB32(avctx->extradata + 8));
|
|
c->free_colours = AV_RB32(avctx->extradata + 48);
|
|
if ((unsigned)c->free_colours > 256) {
|
|
av_log(avctx, AV_LOG_ERROR,
|
|
"Incorrect number of changeable palette entries: %d\n",
|
|
c->free_colours);
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
av_log(avctx, AV_LOG_DEBUG, "%d free colour(s)\n", c->free_colours);
|
|
avctx->coded_width = AV_RB32(avctx->extradata + 20);
|
|
avctx->coded_height = AV_RB32(avctx->extradata + 24);
|
|
|
|
av_log(avctx, AV_LOG_DEBUG, "Display dimensions %dx%d\n",
|
|
AV_RB32(avctx->extradata + 12), AV_RB32(avctx->extradata + 16));
|
|
av_log(avctx, AV_LOG_DEBUG, "Coded dimensions %dx%d\n",
|
|
avctx->coded_width, avctx->coded_height);
|
|
av_log(avctx, AV_LOG_DEBUG, "%g frames per second\n",
|
|
av_int2float(AV_RB32(avctx->extradata + 28)));
|
|
av_log(avctx, AV_LOG_DEBUG, "Bitrate %d bps\n",
|
|
AV_RB32(avctx->extradata + 32));
|
|
av_log(avctx, AV_LOG_DEBUG, "Max. lead time %g ms\n",
|
|
av_int2float(AV_RB32(avctx->extradata + 36)));
|
|
av_log(avctx, AV_LOG_DEBUG, "Max. lag time %g ms\n",
|
|
av_int2float(AV_RB32(avctx->extradata + 40)));
|
|
av_log(avctx, AV_LOG_DEBUG, "Max. seek time %g ms\n",
|
|
av_int2float(AV_RB32(avctx->extradata + 44)));
|
|
|
|
for (i = 0; i < 256; i++)
|
|
c->pal[i] = AV_RB24(avctx->extradata + 52 + i * 3);
|
|
|
|
avctx->pix_fmt = PIX_FMT_PAL8;
|
|
|
|
c->mask_linesize = FFALIGN(avctx->width, 16);
|
|
c->mask = av_malloc(c->mask_linesize * avctx->height);
|
|
if (!c->mask) {
|
|
av_log(avctx, AV_LOG_ERROR, "Cannot allocate mask plane\n");
|
|
return AVERROR(ENOMEM);
|
|
}
|
|
|
|
avctx->coded_frame = &c->pic;
|
|
|
|
codec_init(c);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static av_cold int mss1_decode_end(AVCodecContext *avctx)
|
|
{
|
|
MSS1Context * const c = avctx->priv_data;
|
|
|
|
if (c->pic.data[0])
|
|
avctx->release_buffer(avctx, &c->pic);
|
|
av_freep(&c->mask);
|
|
|
|
return 0;
|
|
}
|
|
|
|
AVCodec ff_mss1_decoder = {
|
|
.name = "mss1",
|
|
.type = AVMEDIA_TYPE_VIDEO,
|
|
.id = CODEC_ID_MSS1,
|
|
.priv_data_size = sizeof(MSS1Context),
|
|
.init = mss1_decode_init,
|
|
.close = mss1_decode_end,
|
|
.decode = mss1_decode_frame,
|
|
.capabilities = CODEC_CAP_DR1,
|
|
.long_name = NULL_IF_CONFIG_SMALL("MS Screen 1"),
|
|
};
|