1 /*
2 * Cryo Interactive Entertainment HNM4 demuxer
3 *
4 * Copyright (c) 2012 David Kment
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 #include <inttypes.h>
24
25 #include "libavutil/intreadwrite.h"
26 #include "avformat.h"
27 #include "internal.h"
28
29 #define HNM4_TAG MKTAG('H', 'N', 'M', '4')
30
31 #define HNM4_SAMPLE_RATE 22050
32 #define HNM4_FRAME_FPS 24
33
34 #define HNM4_CHUNK_ID_PL 19536
35 #define HNM4_CHUNK_ID_IZ 23113
36 #define HNM4_CHUNK_ID_IU 21833
37 #define HNM4_CHUNK_ID_SD 17491
38
39 typedef struct Hnm4DemuxContext {
40 uint32_t frames;
41 uint32_t currentframe;
42 uint32_t superchunk_remaining;
43 } Hnm4DemuxContext;
44
hnm_probe(const AVProbeData * p)45 static int hnm_probe(const AVProbeData *p)
46 {
47 if (p->buf_size < 4)
48 return 0;
49
50 // check for HNM4 header.
51 // currently only HNM v4/v4A is supported
52 if (AV_RL32(&p->buf[0]) == HNM4_TAG)
53 return AVPROBE_SCORE_MAX;
54
55 return 0;
56 }
57
hnm_read_header(AVFormatContext * s)58 static int hnm_read_header(AVFormatContext *s)
59 {
60 Hnm4DemuxContext *hnm = s->priv_data;
61 AVIOContext *pb = s->pb;
62 unsigned width, height;
63 AVStream *vst;
64 int ret;
65
66 avio_skip(pb, 8);
67 width = avio_rl16(pb);
68 height = avio_rl16(pb);
69 avio_rl32(pb); // filesize
70 hnm->frames = avio_rl32(pb);
71 avio_skip(pb, 44);
72
73 if (width < 256 || width > 640 ||
74 height < 150 || height > 480) {
75 av_log(s, AV_LOG_ERROR,
76 "invalid resolution: %ux%u\n", width, height);
77 return AVERROR_INVALIDDATA;
78 }
79
80 if (!(vst = avformat_new_stream(s, NULL)))
81 return AVERROR(ENOMEM);
82
83 vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
84 vst->codecpar->codec_id = AV_CODEC_ID_HNM4_VIDEO;
85 vst->codecpar->codec_tag = 0;
86 vst->codecpar->width = width;
87 vst->codecpar->height = height;
88 if ((ret = ff_alloc_extradata(vst->codecpar, 1)) < 0)
89 return ret;
90
91 // TODO: find a better way to detect HNM4A
92 vst->codecpar->extradata[0] = width == 640 ? 0x4a : 0x40;
93
94 vst->start_time = 0;
95
96 avpriv_set_pts_info(vst, 33, 1, HNM4_FRAME_FPS);
97
98 return 0;
99 }
100
hnm_read_packet(AVFormatContext * s,AVPacket * pkt)101 static int hnm_read_packet(AVFormatContext *s, AVPacket *pkt)
102 {
103 Hnm4DemuxContext *hnm = s->priv_data;
104 AVIOContext *pb = s->pb;
105 int ret = 0;
106
107 uint32_t superchunk_size, chunk_size;
108 uint16_t chunk_id;
109
110 if (hnm->currentframe == hnm->frames || pb->eof_reached)
111 return AVERROR_EOF;
112
113 if (hnm->superchunk_remaining == 0) {
114 /* parse next superchunk */
115 superchunk_size = avio_rl24(pb);
116 avio_skip(pb, 1);
117
118 hnm->superchunk_remaining = superchunk_size - 4;
119 }
120
121 chunk_size = avio_rl24(pb);
122 avio_skip(pb, 1);
123 chunk_id = avio_rl16(pb);
124 avio_skip(pb, 2);
125
126 if (chunk_size > hnm->superchunk_remaining || !chunk_size) {
127 av_log(s, AV_LOG_ERROR,
128 "invalid chunk size: %"PRIu32", offset: %"PRId64"\n",
129 chunk_size, avio_tell(pb));
130 avio_skip(pb, hnm->superchunk_remaining - 8);
131 hnm->superchunk_remaining = 0;
132 }
133
134 switch (chunk_id) {
135 case HNM4_CHUNK_ID_PL:
136 case HNM4_CHUNK_ID_IZ:
137 case HNM4_CHUNK_ID_IU:
138 avio_seek(pb, -8, SEEK_CUR);
139 ret += av_get_packet(pb, pkt, chunk_size);
140 hnm->superchunk_remaining -= chunk_size;
141 if (chunk_id == HNM4_CHUNK_ID_IZ || chunk_id == HNM4_CHUNK_ID_IU)
142 hnm->currentframe++;
143 break;
144
145 case HNM4_CHUNK_ID_SD:
146 avio_skip(pb, chunk_size - 8);
147 hnm->superchunk_remaining -= chunk_size;
148 break;
149
150 default:
151 av_log(s, AV_LOG_WARNING, "unknown chunk found: %"PRIu16", offset: %"PRId64"\n",
152 chunk_id, avio_tell(pb));
153 avio_skip(pb, chunk_size - 8);
154 hnm->superchunk_remaining -= chunk_size;
155 break;
156 }
157
158 return ret;
159 }
160
161 AVInputFormat ff_hnm_demuxer = {
162 .name = "hnm",
163 .long_name = NULL_IF_CONFIG_SMALL("Cryo HNM v4"),
164 .priv_data_size = sizeof(Hnm4DemuxContext),
165 .read_probe = hnm_probe,
166 .read_header = hnm_read_header,
167 .read_packet = hnm_read_packet,
168 .flags = AVFMT_NO_BYTE_SEEK | AVFMT_NOGENSEARCH | AVFMT_NOBINSEARCH
169 };
170