Imported Debian version 2.5.3~trusty1
[deb_ffmpeg.git] / ffmpeg / libavcodec / tak_parser.c
1 /*
2 * TAK parser
3 * Copyright (c) 2012 Michael Niedermayer
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg 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 * FFmpeg 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 FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 /**
23 * @file
24 * TAK parser
25 **/
26
27 #include "tak.h"
28 #include "parser.h"
29
30 typedef struct TAKParseContext {
31 ParseContext pc;
32 TAKStreamInfo ti;
33 int index;
34 } TAKParseContext;
35
36 static int tak_parse(AVCodecParserContext *s, AVCodecContext *avctx,
37 const uint8_t **poutbuf, int *poutbuf_size,
38 const uint8_t *buf, int buf_size)
39 {
40 TAKParseContext *t = s->priv_data;
41 ParseContext *pc = &t->pc;
42 int next = END_NOT_FOUND;
43 GetBitContext gb;
44 int consumed = 0;
45 int needed = buf_size ? TAK_MAX_FRAME_HEADER_BYTES : 8;
46
47 if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
48 TAKStreamInfo ti;
49 init_get_bits(&gb, buf, buf_size);
50 if (!ff_tak_decode_frame_header(avctx, &gb, &ti, 127))
51 s->duration = t->ti.last_frame_samples ? t->ti.last_frame_samples
52 : t->ti.frame_samples;
53 *poutbuf = buf;
54 *poutbuf_size = buf_size;
55 return buf_size;
56 }
57
58 while (buf_size || t->index + needed <= pc->index) {
59 if (buf_size && t->index + TAK_MAX_FRAME_HEADER_BYTES > pc->index) {
60 int tmp_buf_size = FFMIN(2 * TAK_MAX_FRAME_HEADER_BYTES,
61 buf_size);
62 const uint8_t *tmp_buf = buf;
63
64 if (ff_combine_frame(pc, END_NOT_FOUND, &tmp_buf, &tmp_buf_size) != -1)
65 return AVERROR(ENOMEM);
66 consumed += tmp_buf_size;
67 buf += tmp_buf_size;
68 buf_size -= tmp_buf_size;
69 }
70
71 for (; t->index + needed <= pc->index; t->index++) {
72 if (pc->buffer[ t->index ] == 0xFF &&
73 pc->buffer[ t->index + 1 ] == 0xA0) {
74 TAKStreamInfo ti;
75
76 init_get_bits(&gb, pc->buffer + t->index,
77 8 * (pc->index - t->index));
78 if (!ff_tak_decode_frame_header(avctx, &gb,
79 pc->frame_start_found ? &ti : &t->ti, 127) &&
80 !ff_tak_check_crc(pc->buffer + t->index,
81 get_bits_count(&gb) / 8)) {
82 if (!pc->frame_start_found) {
83 pc->frame_start_found = 1;
84 s->duration = t->ti.last_frame_samples ?
85 t->ti.last_frame_samples :
86 t->ti.frame_samples;
87 s->key_frame = !!(t->ti.flags & TAK_FRAME_FLAG_HAS_INFO);
88 } else {
89 pc->frame_start_found = 0;
90 next = t->index - pc->index;
91 t->index = 0;
92 goto found;
93 }
94 }
95 }
96 }
97 }
98 found:
99
100 if (consumed && !buf_size && next == END_NOT_FOUND ||
101 ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
102 *poutbuf = NULL;
103 *poutbuf_size = 0;
104 return buf_size + consumed;
105 }
106
107 if (next != END_NOT_FOUND) {
108 next += consumed;
109 pc->overread = FFMAX(0, -next);
110 }
111
112 *poutbuf = buf;
113 *poutbuf_size = buf_size;
114 return next;
115 }
116
117 AVCodecParser ff_tak_parser = {
118 .codec_ids = { AV_CODEC_ID_TAK },
119 .priv_data_size = sizeof(TAKParseContext),
120 .parser_parse = tak_parse,
121 .parser_close = ff_parse_close,
122 };