FFmpeg  4.0
mss12.h
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1 /*
2  * Copyright (c) 2012 Konstantin Shishkov
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 /**
22  * @file
23  * Common header for Microsoft Screen 1 and 2
24  */
25 
26 #ifndef AVCODEC_MSS12_H
27 #define AVCODEC_MSS12_H
28 
29 #include "libavutil/intreadwrite.h"
30 #include "avcodec.h"
31 #include "get_bits.h"
32 #include "bytestream.h"
33 
34 #define MODEL_MIN_SYMS 2
35 #define MODEL_MAX_SYMS 256
36 #define THRESH_ADAPTIVE -1
37 #define THRESH_LOW 15
38 #define THRESH_HIGH 50
39 
40 typedef struct Model {
41  int16_t cum_prob[MODEL_MAX_SYMS + 1];
42  int16_t weights[MODEL_MAX_SYMS + 1];
44  int num_syms;
46 } Model;
47 
48 typedef struct ArithCoder {
49  int low, high, value;
50  union {
53  } gbc;
54  int (*get_model_sym)(struct ArithCoder *c, Model *m);
55  int (*get_number) (struct ArithCoder *c, int n);
56 } ArithCoder;
57 
58 typedef struct PixContext {
59  int cache_size, num_syms;
60  uint8_t cache[12];
61  Model cache_model, full_model;
62  Model sec_models[15][4];
64 } PixContext;
65 
66 struct MSS12Context;
67 
68 typedef struct SliceContext {
69  struct MSS12Context *c;
70  Model intra_region, inter_region;
71  Model pivot, edge_mode, split_mode;
72  PixContext intra_pix_ctx, inter_pix_ctx;
73 } SliceContext;
74 
75 typedef struct MSS12Context {
77  uint32_t pal[256];
80  ptrdiff_t pal_stride;
82  ptrdiff_t mask_stride;
85  ptrdiff_t rgb_stride;
87  int keyframe;
88  int mvX, mvY;
89  int corrupted;
92 } MSS12Context;
93 
95  int x, int y, int width, int height);
96 void ff_mss12_model_update(Model *m, int val);
99  SliceContext *sc1, SliceContext *sc2);
101 
102 #define ARITH_GET_BIT(prefix) \
103 static int prefix ## _get_bit(ArithCoder *c) \
104 { \
105  int range = c->high - c->low + 1; \
106  int bit = 2 * c->value - c->low >= c->high; \
107  \
108  if (bit) \
109  c->low += range >> 1; \
110  else \
111  c->high = c->low + (range >> 1) - 1; \
112  \
113  prefix ## _normalise(c); \
114  \
115  return bit; \
116 }
117 
118 #define ARITH_GET_MODEL_SYM(prefix) \
119 static int prefix ## _get_model_sym(ArithCoder *c, Model *m) \
120 { \
121  int idx, val; \
122  \
123  idx = prefix ## _get_prob(c, m->cum_prob); \
124  \
125  val = m->idx2sym[idx]; \
126  ff_mss12_model_update(m, idx); \
127  \
128  prefix ## _normalise(c); \
129  \
130  return val; \
131 }
132 
133 #endif /* AVCODEC_MSS12_H */
const char const char void * val
Definition: avisynth_c.h:771
Definition: mss12.h:40
int value
Definition: mss12.h:49
int corrupted
Definition: mss12.h:89
int16_t weights[MODEL_MAX_SYMS+1]
Definition: mss12.h:42
int version
Definition: avisynth_c.h:766
uint8_t * rgb_pic
Definition: mss12.h:83
int thr_weight
Definition: mss12.h:45
int slice_split
Definition: mss12.h:90
uint8_t
uint8_t * last_pal_pic
Definition: mss12.h:79
int keyframe
Definition: mss12.h:87
ptrdiff_t rgb_stride
Definition: mss12.h:85
#define height
GetByteContext * gB
Definition: mss12.h:52
bitstream reader API header.
Model full_model
Definition: mss12.h:61
static int get_number(void *obj, const char *name, const AVOption **o_out, double *num, int *den, int64_t *intnum, int search_flags)
Definition: opt.c:855
int full_model_syms
Definition: mss12.h:91
int mvY
Definition: mss12.h:88
uint16_t width
Definition: gdv.c:47
AVCodecContext * avctx
Definition: mss12.h:76
PixContext intra_pix_ctx
Definition: mss12.h:72
#define MODEL_MAX_SYMS
Definition: mss12.h:35
AVFormatContext * ctx
Definition: movenc.c:48
ptrdiff_t pal_stride
Definition: mss12.h:80
int n
Definition: avisynth_c.h:684
struct MSS12Context * c
Definition: mss12.h:69
int ff_mss12_decode_end(MSS12Context *ctx)
Definition: mss12.c:677
Libavcodec external API header.
int ff_mss12_decode_rect(SliceContext *ctx, ArithCoder *acoder, int x, int y, int width, int height)
Definition: mss12.c:529
uint8_t * mask
Definition: mss12.h:81
main external API structure.
Definition: avcodec.h:1518
int num_syms
Definition: mss12.h:44
int ff_mss12_decode_init(MSS12Context *c, int version, SliceContext *sc1, SliceContext *sc2)
Definition: mss12.c:565
uint8_t idx2sym[MODEL_MAX_SYMS+1]
Definition: mss12.h:43
int special_initial_cache
Definition: mss12.h:63
Model split_mode
Definition: mss12.h:71
void ff_mss12_slicecontext_reset(SliceContext *sc)
Definition: mss12.c:429
int
static double c[64]
int threshold
Definition: mss12.h:45
int free_colours
Definition: mss12.h:86
ptrdiff_t mask_stride
Definition: mss12.h:82
uint8_t * last_rgb_pic
Definition: mss12.h:84
Model intra_region
Definition: mss12.h:70
GetBitContext * gb
Definition: mss12.h:51
int num_syms
Definition: mss12.h:59
uint8_t * pal_pic
Definition: mss12.h:78
void ff_mss12_model_update(Model *m, int val)
Definition: mss12.c:95
int16_t cum_prob[MODEL_MAX_SYMS+1]
Definition: mss12.h:41