yading@10: /* yading@10: * Copyright (c) 2012 Konstantin Shishkov yading@10: * yading@10: * This file is part of FFmpeg. yading@10: * yading@10: * FFmpeg is free software; you can redistribute it and/or yading@10: * modify it under the terms of the GNU Lesser General Public yading@10: * License as published by the Free Software Foundation; either yading@10: * version 2.1 of the License, or (at your option) any later version. yading@10: * yading@10: * FFmpeg is distributed in the hope that it will be useful, yading@10: * but WITHOUT ANY WARRANTY; without even the implied warranty of yading@10: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU yading@10: * Lesser General Public License for more details. yading@10: * yading@10: * You should have received a copy of the GNU Lesser General Public yading@10: * License along with FFmpeg; if not, write to the Free Software yading@10: * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA yading@10: */ yading@10: yading@10: /** yading@10: * @file yading@10: * Common header for Microsoft Screen 1 and 2 yading@10: */ yading@10: yading@10: #ifndef AVCODEC_MSS12_H yading@10: #define AVCODEC_MSS12_H yading@10: yading@10: #include "libavutil/intreadwrite.h" yading@10: #include "avcodec.h" yading@10: #include "get_bits.h" yading@10: #include "bytestream.h" yading@10: yading@10: #define MODEL_MIN_SYMS 2 yading@10: #define MODEL_MAX_SYMS 256 yading@10: #define THRESH_ADAPTIVE -1 yading@10: #define THRESH_LOW 15 yading@10: #define THRESH_HIGH 50 yading@10: yading@10: typedef struct Model { yading@10: int16_t cum_prob[MODEL_MAX_SYMS + 1]; yading@10: int16_t weights[MODEL_MAX_SYMS + 1]; yading@10: uint8_t idx2sym[MODEL_MAX_SYMS + 1]; yading@10: int num_syms; yading@10: int thr_weight, threshold; yading@10: } Model; yading@10: yading@10: typedef struct ArithCoder { yading@10: int low, high, value; yading@10: union { yading@10: GetBitContext *gb; yading@10: GetByteContext *gB; yading@10: } gbc; yading@10: int (*get_model_sym)(struct ArithCoder *c, Model *m); yading@10: int (*get_number) (struct ArithCoder *c, int n); yading@10: } ArithCoder; yading@10: yading@10: typedef struct PixContext { yading@10: int cache_size, num_syms; yading@10: uint8_t cache[12]; yading@10: Model cache_model, full_model; yading@10: Model sec_models[15][4]; yading@10: int special_initial_cache; yading@10: } PixContext; yading@10: yading@10: struct MSS12Context; yading@10: yading@10: typedef struct SliceContext { yading@10: struct MSS12Context *c; yading@10: Model intra_region, inter_region; yading@10: Model pivot, edge_mode, split_mode; yading@10: PixContext intra_pix_ctx, inter_pix_ctx; yading@10: } SliceContext; yading@10: yading@10: typedef struct MSS12Context { yading@10: AVCodecContext *avctx; yading@10: uint32_t pal[256]; yading@10: uint8_t *pal_pic; yading@10: uint8_t *last_pal_pic; yading@10: int pal_stride; yading@10: uint8_t *mask; yading@10: int mask_stride; yading@10: uint8_t *rgb_pic; yading@10: uint8_t *last_rgb_pic; yading@10: int rgb_stride; yading@10: int free_colours; yading@10: int keyframe; yading@10: int mvX, mvY; yading@10: int corrupted; yading@10: int slice_split; yading@10: int full_model_syms; yading@10: } MSS12Context; yading@10: yading@10: int ff_mss12_decode_rect(SliceContext *ctx, ArithCoder *acoder, yading@10: int x, int y, int width, int height); yading@10: void ff_mss12_model_update(Model *m, int val); yading@10: void ff_mss12_slicecontext_reset(SliceContext *sc); yading@10: int ff_mss12_decode_init(MSS12Context *c, int version, yading@10: SliceContext *sc1, SliceContext *sc2); yading@10: int ff_mss12_decode_end(MSS12Context *ctx); yading@10: yading@10: #define ARITH_GET_BIT(VERSION) \ yading@10: static int arith ## VERSION ## _get_bit(ArithCoder *c) \ yading@10: { \ yading@10: int range = c->high - c->low + 1; \ yading@10: int bit = 2 * c->value - c->low >= c->high; \ yading@10: \ yading@10: if (bit) \ yading@10: c->low += range >> 1; \ yading@10: else \ yading@10: c->high = c->low + (range >> 1) - 1; \ yading@10: \ yading@10: arith ## VERSION ## _normalise(c); \ yading@10: \ yading@10: return bit; \ yading@10: } yading@10: yading@10: #define ARITH_GET_MODEL_SYM(VERSION) \ yading@10: static int arith ## VERSION ## _get_model_sym(ArithCoder *c, Model *m) \ yading@10: { \ yading@10: int idx, val; \ yading@10: \ yading@10: idx = arith ## VERSION ## _get_prob(c, m->cum_prob); \ yading@10: \ yading@10: val = m->idx2sym[idx]; \ yading@10: ff_mss12_model_update(m, idx); \ yading@10: \ yading@10: arith ## VERSION ## _normalise(c); \ yading@10: \ yading@10: return val; \ yading@10: } yading@10: yading@10: #endif /* AVCODEC_MSS12_H */