1 /*
2 * FFV1 codec for libavcodec
3 *
4 * Copyright (c) 2003-2012 Michael Niedermayer <michaelni@gmx.at>
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23 #ifndef AVCODEC_FFV1_H
24 #define AVCODEC_FFV1_H
25
26 /**
27 * @file
28 * FF Video Codec 1 (a lossless codec)
29 */
30
31 #include "libavutil/avassert.h"
32 #include "libavutil/crc.h"
33 #include "libavutil/opt.h"
34 #include "libavutil/imgutils.h"
35 #include "libavutil/pixdesc.h"
36 #include "libavutil/timer.h"
37 #include "avcodec.h"
38 #include "get_bits.h"
39 #include "internal.h"
40 #include "mathops.h"
41 #include "put_bits.h"
42 #include "rangecoder.h"
43 #include "thread.h"
44
45 #ifdef __INTEL_COMPILER
46 #undef av_flatten
47 #define av_flatten
48 #endif
49
50 #define MAX_PLANES 4
51 #define CONTEXT_SIZE 32
52
53 #define MAX_QUANT_TABLES 8
54 #define MAX_CONTEXT_INPUTS 5
55
56 typedef struct VlcState {
57 int16_t drift;
58 uint16_t error_sum;
59 int8_t bias;
60 uint8_t count;
61 } VlcState;
62
63 typedef struct PlaneContext {
64 int16_t quant_table[MAX_CONTEXT_INPUTS][256];
65 int quant_table_index;
66 int context_count;
67 uint8_t (*state)[CONTEXT_SIZE];
68 VlcState *vlc_state;
69 uint8_t interlace_bit_state[2];
70 } PlaneContext;
71
72 #define MAX_SLICES 256
73
74 typedef struct FFV1Context {
75 AVClass *class;
76 AVCodecContext *avctx;
77 RangeCoder c;
78 GetBitContext gb;
79 PutBitContext pb;
80 uint64_t rc_stat[256][2];
81 uint64_t (*rc_stat2[MAX_QUANT_TABLES])[32][2];
82 int version;
83 int micro_version;
84 int width, height;
85 int chroma_planes;
86 int chroma_h_shift, chroma_v_shift;
87 int transparency;
88 int flags;
89 int picture_number;
90 ThreadFrame picture, last_picture;
91 struct FFV1Context *fsrc;
92
93 AVFrame *cur;
94 int plane_count;
95 int ac; ///< 1=range coder <-> 0=golomb rice
96 int ac_byte_count; ///< number of bytes used for AC coding
97 PlaneContext plane[MAX_PLANES];
98 int16_t quant_table[MAX_CONTEXT_INPUTS][256];
99 int16_t quant_tables[MAX_QUANT_TABLES][MAX_CONTEXT_INPUTS][256];
100 int context_count[MAX_QUANT_TABLES];
101 uint8_t state_transition[256];
102 uint8_t (*initial_states[MAX_QUANT_TABLES])[32];
103 int run_index;
104 int colorspace;
105 int16_t *sample_buffer;
106
107 int ec;
108 int intra;
109 int slice_damaged;
110 int key_frame_ok;
111
112 int bits_per_raw_sample;
113 int packed_at_lsb;
114
115 int gob_count;
116 int quant_table_count;
117
118 struct FFV1Context *slice_context[MAX_SLICES];
119 int slice_count;
120 int num_v_slices;
121 int num_h_slices;
122 int slice_width;
123 int slice_height;
124 int slice_x;
125 int slice_y;
126 int slice_reset_contexts;
127 int slice_coding_mode;
128 int slice_rct_by_coef;
129 int slice_rct_ry_coef;
130 } FFV1Context;
131
132 int ffv1_common_init(AVCodecContext *avctx);
133 int ffv1_init_slice_state(FFV1Context *f, FFV1Context *fs);
134 int ffv1_init_slices_state(FFV1Context *f);
135 int ffv1_init_slice_contexts(FFV1Context *f);
136 int ffv1_allocate_initial_states(FFV1Context *f);
137 void ffv1_clear_slice_state(FFV1Context *f, FFV1Context *fs);
138 int ffv1_close(AVCodecContext *avctx);
139
fold(int diff,int bits)140 static av_always_inline int fold(int diff, int bits)
141 {
142 if (bits == 8)
143 diff = (int8_t)diff;
144 else {
145 diff += 1 << (bits - 1);
146 diff &= (1 << bits) - 1;
147 diff -= 1 << (bits - 1);
148 }
149
150 return diff;
151 }
152
predict(int16_t * src,int16_t * last)153 static inline int predict(int16_t *src, int16_t *last)
154 {
155 const int LT = last[-1];
156 const int T = last[0];
157 const int L = src[-1];
158
159 return mid_pred(L, L + T - LT, T);
160 }
161
get_context(PlaneContext * p,int16_t * src,int16_t * last,int16_t * last2)162 static inline int get_context(PlaneContext *p, int16_t *src,
163 int16_t *last, int16_t *last2)
164 {
165 const int LT = last[-1];
166 const int T = last[0];
167 const int RT = last[1];
168 const int L = src[-1];
169
170 if (p->quant_table[3][127]) {
171 const int TT = last2[0];
172 const int LL = src[-2];
173 return p->quant_table[0][(L - LT) & 0xFF] +
174 p->quant_table[1][(LT - T) & 0xFF] +
175 p->quant_table[2][(T - RT) & 0xFF] +
176 p->quant_table[3][(LL - L) & 0xFF] +
177 p->quant_table[4][(TT - T) & 0xFF];
178 } else
179 return p->quant_table[0][(L - LT) & 0xFF] +
180 p->quant_table[1][(LT - T) & 0xFF] +
181 p->quant_table[2][(T - RT) & 0xFF];
182 }
183
update_vlc_state(VlcState * const state,const int v)184 static inline void update_vlc_state(VlcState *const state, const int v)
185 {
186 int drift = state->drift;
187 int count = state->count;
188 state->error_sum += FFABS(v);
189 drift += v;
190
191 if (count == 128) { // FIXME: variable
192 count >>= 1;
193 drift >>= 1;
194 state->error_sum >>= 1;
195 }
196 count++;
197
198 if (drift <= -count) {
199 if (state->bias > -128)
200 state->bias--;
201
202 drift += count;
203 if (drift <= -count)
204 drift = -count + 1;
205 } else if (drift > 0) {
206 if (state->bias < 127)
207 state->bias++;
208
209 drift -= count;
210 if (drift > 0)
211 drift = 0;
212 }
213
214 state->drift = drift;
215 state->count = count;
216 }
217
218 #endif /* AVCODEC_FFV1_H */
219