1 /*
2 * DVD navigation block parser for FFmpeg
3 * Copyright (c) 2013 The FFmpeg Project
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 #include "avcodec.h"
22 #include "get_bits.h"
23 #include "parser.h"
24
25 #define PCI_SIZE 980
26 #define DSI_SIZE 1018
27
28 /* parser definition */
29 typedef struct DVDNavParseContext {
30 uint32_t lba;
31 uint8_t buffer[PCI_SIZE+DSI_SIZE];
32 int copied;
33 } DVDNavParseContext;
34
dvd_nav_parse_init(AVCodecParserContext * s)35 static av_cold int dvd_nav_parse_init(AVCodecParserContext *s)
36 {
37 DVDNavParseContext *pc = s->priv_data;
38
39 pc->lba = 0xFFFFFFFF;
40 pc->copied = 0;
41 return 0;
42 }
43
dvd_nav_parse(AVCodecParserContext * s,AVCodecContext * avctx,const uint8_t ** poutbuf,int * poutbuf_size,const uint8_t * buf,int buf_size)44 static int dvd_nav_parse(AVCodecParserContext *s,
45 AVCodecContext *avctx,
46 const uint8_t **poutbuf, int *poutbuf_size,
47 const uint8_t *buf, int buf_size)
48 {
49 DVDNavParseContext *pc1 = s->priv_data;
50 int lastPacket = 0;
51 int valid = 0;
52
53 s->pict_type = AV_PICTURE_TYPE_NONE;
54
55 avctx->time_base.num = 1;
56 avctx->time_base.den = 90000;
57
58 if (buf && buf_size) {
59 switch(buf[0]) {
60 case 0x00:
61 if (buf_size == PCI_SIZE) {
62 /* PCI */
63 uint32_t lba = AV_RB32(&buf[0x01]);
64 uint32_t startpts = AV_RB32(&buf[0x0D]);
65 uint32_t endpts = AV_RB32(&buf[0x11]);
66
67 if (endpts > startpts) {
68 pc1->lba = lba;
69 s->pts = (int64_t)startpts;
70 s->duration = endpts - startpts;
71
72 memcpy(pc1->buffer, buf, PCI_SIZE);
73 pc1->copied = PCI_SIZE;
74 valid = 1;
75 }
76 }
77 break;
78
79 case 0x01:
80 if ((buf_size == DSI_SIZE) && (pc1->copied == PCI_SIZE)) {
81 /* DSI */
82 uint32_t lba = AV_RB32(&buf[0x05]);
83
84 if (lba == pc1->lba) {
85 memcpy(pc1->buffer + pc1->copied, buf, DSI_SIZE);
86 lastPacket = 1;
87 valid = 1;
88 }
89 }
90 break;
91 }
92 }
93
94 if (!valid || lastPacket) {
95 pc1->copied = 0;
96 pc1->lba = 0xFFFFFFFF;
97 }
98
99 if (lastPacket) {
100 *poutbuf = pc1->buffer;
101 *poutbuf_size = sizeof(pc1->buffer);
102 } else {
103 *poutbuf = NULL;
104 *poutbuf_size = 0;
105 }
106
107 return buf_size;
108 }
109
110 AVCodecParser ff_dvd_nav_parser = {
111 .codec_ids = { AV_CODEC_ID_DVD_NAV },
112 .priv_data_size = sizeof(DVDNavParseContext),
113 .parser_init = dvd_nav_parse_init,
114 .parser_parse = dvd_nav_parse,
115 };
116