dnxhd_parser.c
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1 /*
2  * DNxHD/VC-3 parser
3  * Copyright (c) 2008 Baptiste Coudurier <baptiste.coudurier@free.fr>
4  *
5  * This file is part of Libav.
6  *
7  * Libav is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * Libav is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
27 #include "parser.h"
28 
29 #define DNXHD_HEADER_PREFIX 0x0000028001
30 
32  const uint8_t *buf, int buf_size)
33 {
34  uint64_t state = pc->state64;
35  int pic_found = pc->frame_start_found;
36  int i = 0;
37 
38  if (!pic_found) {
39  for (i = 0; i < buf_size; i++) {
40  state = (state<<8) | buf[i];
41  if ((state & 0xffffffffffLL) == DNXHD_HEADER_PREFIX) {
42  i++;
43  pic_found = 1;
44  break;
45  }
46  }
47  }
48 
49  if (pic_found) {
50  if (!buf_size) /* EOF considered as end of frame */
51  return 0;
52  for (; i < buf_size; i++) {
53  state = (state<<8) | buf[i];
54  if ((state & 0xffffffffffLL) == DNXHD_HEADER_PREFIX) {
55  pc->frame_start_found = 0;
56  pc->state64 = -1;
57  return i-4;
58  }
59  }
60  }
61  pc->frame_start_found = pic_found;
62  pc->state64 = state;
63  return END_NOT_FOUND;
64 }
65 
67  AVCodecContext *avctx,
68  const uint8_t **poutbuf, int *poutbuf_size,
69  const uint8_t *buf, int buf_size)
70 {
71  ParseContext *pc = s->priv_data;
72  int next;
73 
75  next = buf_size;
76  } else {
77  next = dnxhd_find_frame_end(pc, buf, buf_size);
78  if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
79  *poutbuf = NULL;
80  *poutbuf_size = 0;
81  return buf_size;
82  }
83  }
84  *poutbuf = buf;
85  *poutbuf_size = buf_size;
86  return next;
87 }
88 
91  .priv_data_size = sizeof(ParseContext),
92  .parser_parse = dnxhd_parse,
93  .parser_close = ff_parse_close,
94 };