mirror of https://github.com/FFmpeg/FFmpeg.git
Kostya Shishkov
13 years ago
parent
43886eaebc
commit
005c80b645
8 changed files with 853 additions and 1 deletions
@ -0,0 +1,845 @@ |
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/*
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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); |
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model_reset(&ctx->edge_mode); |
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model_reset(&ctx->pivot); |
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pixctx_reset(&ctx->intra_pix_ctx); |
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pixctx_reset(&ctx->inter_pix_ctx); |
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ctx->corrupted = 0; |
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} |
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static int decode_pal(MSS1Context *ctx, ArithCoder *acoder) |
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{ |
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int i, ncol, r, g, b; |
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uint32_t *pal = ctx->pal + 256 - ctx->free_colours; |
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if (!ctx->free_colours) |
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return 0; |
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ncol = arith_get_number(acoder, ctx->free_colours + 1); |
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for (i = 0; i < ncol; i++) { |
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r = arith_get_bits(acoder, 8); |
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g = arith_get_bits(acoder, 8); |
||||
b = arith_get_bits(acoder, 8); |
||||
*pal++ = (r << 16) | (g << 8) | b; |
||||
} |
||||
|
||||
return 0; |
||||
} |
||||
|
||||
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); |
||||
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"), |
||||
}; |
||||
Loading…
Reference in new issue