FFmpeg
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ffv1.c
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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 /**
24  * @file
25  * FF Video Codec 1 (a lossless codec)
26  */
27 
28 #include "libavutil/avassert.h"
29 #include "libavutil/crc.h"
30 #include "libavutil/opt.h"
31 #include "libavutil/imgutils.h"
32 #include "libavutil/pixdesc.h"
33 #include "libavutil/timer.h"
34 #include "avcodec.h"
35 #include "internal.h"
36 #include "rangecoder.h"
37 #include "golomb.h"
38 #include "mathops.h"
39 #include "ffv1.h"
40 
42 {
43  FFV1Context *s = avctx->priv_data;
44 
45  if (!avctx->width || !avctx->height)
46  return AVERROR_INVALIDDATA;
47 
48  s->avctx = avctx;
49  s->flags = avctx->flags;
50 
52 
53  ff_dsputil_init(&s->dsp, avctx);
54 
55  s->width = avctx->width;
56  s->height = avctx->height;
57 
58  // defaults
59  s->num_h_slices = 1;
60  s->num_v_slices = 1;
61 
62  return 0;
63 }
64 
66 {
67  int j;
68 
69  fs->plane_count = f->plane_count;
70  fs->transparency = f->transparency;
71  for (j = 0; j < f->plane_count; j++) {
72  PlaneContext *const p = &fs->plane[j];
73 
74  if (fs->ac) {
75  if (!p->state)
77  sizeof(uint8_t));
78  if (!p->state)
79  return AVERROR(ENOMEM);
80  } else {
81  if (!p->vlc_state)
82  p->vlc_state = av_malloc(p->context_count * sizeof(VlcState));
83  if (!p->vlc_state)
84  return AVERROR(ENOMEM);
85  }
86  }
87 
88  if (fs->ac > 1) {
89  //FIXME only redo if state_transition changed
90  for (j = 1; j < 256; j++) {
91  fs->c. one_state[ j] = f->state_transition[j];
92  fs->c.zero_state[256 - j] = 256 - fs->c.one_state[j];
93  }
94  }
95 
96  return 0;
97 }
98 
100 {
101  int i, ret;
102  for (i = 0; i < f->slice_count; i++) {
103  FFV1Context *fs = f->slice_context[i];
104  if ((ret = ffv1_init_slice_state(f, fs)) < 0)
105  return AVERROR(ENOMEM);
106  }
107  return 0;
108 }
109 
111 {
112  int i;
113 
115  av_assert0(f->slice_count > 0);
116 
117  for (i = 0; i < f->slice_count; i++) {
118  FFV1Context *fs = av_mallocz(sizeof(*fs));
119  int sx = i % f->num_h_slices;
120  int sy = i / f->num_h_slices;
121  int sxs = f->avctx->width * sx / f->num_h_slices;
122  int sxe = f->avctx->width * (sx + 1) / f->num_h_slices;
123  int sys = f->avctx->height * sy / f->num_v_slices;
124  int sye = f->avctx->height * (sy + 1) / f->num_v_slices;
125 
126  if (!fs)
127  return AVERROR(ENOMEM);
128 
129  f->slice_context[i] = fs;
130  memcpy(fs, f, sizeof(*fs));
131  memset(fs->rc_stat2, 0, sizeof(fs->rc_stat2));
132 
133  fs->slice_width = sxe - sxs;
134  fs->slice_height = sye - sys;
135  fs->slice_x = sxs;
136  fs->slice_y = sys;
137 
138  fs->sample_buffer = av_malloc(3 * MAX_PLANES * (fs->width + 6) *
139  sizeof(*fs->sample_buffer));
140  if (!fs->sample_buffer)
141  return AVERROR(ENOMEM);
142  }
143  return 0;
144 }
145 
147 {
148  int i;
149 
150  for (i = 0; i < f->quant_table_count; i++) {
151  f->initial_states[i] = av_malloc(f->context_count[i] *
152  sizeof(*f->initial_states[i]));
153  if (!f->initial_states[i])
154  return AVERROR(ENOMEM);
155  memset(f->initial_states[i], 128,
156  f->context_count[i] * sizeof(*f->initial_states[i]));
157  }
158  return 0;
159 }
160 
162 {
163  int i, j;
164 
165  for (i = 0; i < f->plane_count; i++) {
166  PlaneContext *p = &fs->plane[i];
167 
168  p->interlace_bit_state[0] = 128;
169  p->interlace_bit_state[1] = 128;
170 
171  if (fs->ac) {
172  if (f->initial_states[p->quant_table_index]) {
173  memcpy(p->state, f->initial_states[p->quant_table_index],
175  } else
176  memset(p->state, 128, CONTEXT_SIZE * p->context_count);
177  } else {
178  for (j = 0; j < p->context_count; j++) {
179  p->vlc_state[j].drift = 0;
180  p->vlc_state[j].error_sum = 4; //FFMAX((RANGE + 32)/64, 2);
181  p->vlc_state[j].bias = 0;
182  p->vlc_state[j].count = 1;
183  }
184  }
185  }
186 }
187 
188 
190 {
191  FFV1Context *s = avctx->priv_data;
192  int i, j;
193 
194  if (avctx->codec->decode && s->picture.data[0])
195  avctx->release_buffer(avctx, &s->picture);
196  if (avctx->codec->decode && s->last_picture.data[0])
197  avctx->release_buffer(avctx, &s->last_picture);
198 
199  for (j = 0; j < s->slice_count; j++) {
200  FFV1Context *fs = s->slice_context[j];
201  for (i = 0; i < s->plane_count; i++) {
202  PlaneContext *p = &fs->plane[i];
203 
204  av_freep(&p->state);
205  av_freep(&p->vlc_state);
206  }
207  av_freep(&fs->sample_buffer);
208  }
209 
210  av_freep(&avctx->stats_out);
211  for (j = 0; j < s->quant_table_count; j++) {
212  av_freep(&s->initial_states[j]);
213  for (i = 0; i < s->slice_count; i++) {
214  FFV1Context *sf = s->slice_context[i];
215  av_freep(&sf->rc_stat2[j]);
216  }
217  av_freep(&s->rc_stat2[j]);
218  }
219 
220  for (i = 0; i < s->slice_count; i++)
221  av_freep(&s->slice_context[i]);
222 
223  return 0;
224 }