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hnm.c
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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 "libavutil/intreadwrite.h"
24 #include "avformat.h"
25 #include "internal.h"
26 
27 #define HNM4_TAG MKTAG('H', 'N', 'M', '4')
28 
29 #define HNM4_SAMPLE_RATE 22050
30 #define HNM4_FRAME_FPS 24
31 
32 #define HNM4_CHUNK_ID_PL 19536
33 #define HNM4_CHUNK_ID_IZ 23113
34 #define HNM4_CHUNK_ID_IU 21833
35 #define HNM4_CHUNK_ID_SD 17491
36 
37 typedef struct Hnm4DemuxContext {
39  uint16_t width;
40  uint16_t height;
41  uint32_t filesize;
42  uint32_t frames;
43  uint32_t taboffset;
44  uint16_t bits;
45  uint16_t channels;
46  uint32_t framesize;
47  uint32_t currentframe;
48  int64_t pts;
52 
53 static int hnm_probe(AVProbeData *p)
54 {
55  if (p->buf_size < 4)
56  return 0;
57 
58  // check for HNM4 header.
59  // currently only HNM v4/v4A is supported
60  if (AV_RL32(&p->buf[0]) == HNM4_TAG)
61  return AVPROBE_SCORE_MAX;
62 
63  return 0;
64 }
65 
67 {
68  Hnm4DemuxContext *hnm = s->priv_data;
69  AVIOContext *pb = s->pb;
70  AVStream *vst;
71 
72  /* default context members */
73  hnm->pts = 0;
74  av_init_packet(&hnm->vpkt);
75  hnm->vpkt.data = NULL;
76  hnm->vpkt.size = 0;
77 
78  hnm->superchunk_remaining = 0;
79 
80  avio_skip(pb, 8);
81  hnm->width = avio_rl16(pb);
82  hnm->height = avio_rl16(pb);
83  hnm->filesize = avio_rl32(pb);
84  hnm->frames = avio_rl32(pb);
85  hnm->taboffset = avio_rl32(pb);
86  hnm->bits = avio_rl16(pb);
87  hnm->channels = avio_rl16(pb);
88  hnm->framesize = avio_rl32(pb);
89  avio_skip(pb, 32);
90 
91  hnm->currentframe = 0;
92 
93  if (hnm->width < 320 || hnm->width > 640 ||
94  hnm->height < 150 || hnm->height > 480) {
96  "invalid resolution: %ux%u\n", hnm->width, hnm->height);
97  return AVERROR_INVALIDDATA;
98  }
99 
100  // TODO: find a better way to detect HNM4A
101  if (hnm->width == 640)
102  hnm->version = 0x4a;
103  else
104  hnm->version = 0x40;
105 
106  if (!(vst = avformat_new_stream(s, NULL)))
107  return AVERROR(ENOMEM);
108 
111  vst->codec->codec_tag = 0;
112  vst->codec->width = hnm->width;
113  vst->codec->height = hnm->height;
114  vst->codec->extradata = av_mallocz(1);
115 
116  vst->codec->extradata_size = 1;
117  memcpy(vst->codec->extradata, &hnm->version, 1);
118 
119  vst->start_time = 0;
120 
121  avpriv_set_pts_info(vst, 33, 1, HNM4_FRAME_FPS);
122 
123  return 0;
124 }
125 
127 {
128  Hnm4DemuxContext *hnm = s->priv_data;
129  AVIOContext *pb = s->pb;
130  int ret = 0;
131 
132  uint32_t superchunk_size, chunk_size;
133  uint16_t chunk_id;
134 
135  if (hnm->currentframe == hnm->frames || pb->eof_reached)
136  return AVERROR_EOF;
137 
138  if (hnm->superchunk_remaining == 0) {
139  /* parse next superchunk */
140  superchunk_size = avio_rl24(pb);
141  avio_skip(pb, 1);
142 
143  hnm->superchunk_remaining = superchunk_size - 4;
144  }
145 
146  chunk_size = avio_rl24(pb);
147  avio_skip(pb, 1);
148  chunk_id = avio_rl16(pb);
149  avio_skip(pb, 2);
150 
151  if (chunk_size > hnm->superchunk_remaining || !chunk_size) {
152  av_log(s, AV_LOG_ERROR, "invalid chunk size: %u, offset: %u\n",
153  chunk_size, (int) avio_tell(pb));
154  avio_skip(pb, hnm->superchunk_remaining - 8);
155  hnm->superchunk_remaining = 0;
156  }
157 
158  switch (chunk_id) {
159  case HNM4_CHUNK_ID_PL:
160  case HNM4_CHUNK_ID_IZ:
161  case HNM4_CHUNK_ID_IU:
162  avio_seek(pb, -8, SEEK_CUR);
163  ret += av_get_packet(pb, pkt, chunk_size);
164  hnm->superchunk_remaining -= chunk_size;
165  if (chunk_id == HNM4_CHUNK_ID_IZ || chunk_id == HNM4_CHUNK_ID_IU)
166  hnm->currentframe++;
167  break;
168 
169  case HNM4_CHUNK_ID_SD:
170  avio_skip(pb, chunk_size - 8);
171  hnm->superchunk_remaining -= chunk_size;
172  break;
173 
174  default:
175  av_log(s, AV_LOG_WARNING, "unknown chunk found: %d, offset: %d\n",
176  chunk_id, (int) avio_tell(pb));
177  avio_skip(pb, chunk_size - 8);
178  hnm->superchunk_remaining -= chunk_size;
179  break;
180  }
181 
182  return ret;
183 }
184 
186 {
187  Hnm4DemuxContext *hnm = s->priv_data;
188 
189  if (hnm->vpkt.size > 0)
190  av_free_packet(&hnm->vpkt);
191 
192  return 0;
193 }
194 
196  .name = "hnm",
197  .long_name = NULL_IF_CONFIG_SMALL("Cryo HNM v4"),
198  .priv_data_size = sizeof(Hnm4DemuxContext),
204 };