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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 <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 {
41  uint16_t width;
42  uint16_t height;
43  uint32_t filesize;
44  uint32_t frames;
45  uint32_t taboffset;
46  uint16_t bits;
47  uint16_t channels;
48  uint32_t framesize;
49  uint32_t currentframe;
50  int64_t pts;
54 
55 static int hnm_probe(AVProbeData *p)
56 {
57  if (p->buf_size < 4)
58  return 0;
59 
60  // check for HNM4 header.
61  // currently only HNM v4/v4A is supported
62  if (AV_RL32(&p->buf[0]) == HNM4_TAG)
63  return AVPROBE_SCORE_MAX;
64 
65  return 0;
66 }
67 
69 {
70  Hnm4DemuxContext *hnm = s->priv_data;
71  AVIOContext *pb = s->pb;
72  AVStream *vst;
73 
74  /* default context members */
75  hnm->pts = 0;
76  av_init_packet(&hnm->vpkt);
77  hnm->vpkt.data = NULL;
78  hnm->vpkt.size = 0;
79 
80  hnm->superchunk_remaining = 0;
81 
82  avio_skip(pb, 8);
83  hnm->width = avio_rl16(pb);
84  hnm->height = avio_rl16(pb);
85  hnm->filesize = avio_rl32(pb);
86  hnm->frames = avio_rl32(pb);
87  hnm->taboffset = avio_rl32(pb);
88  hnm->bits = avio_rl16(pb);
89  hnm->channels = avio_rl16(pb);
90  hnm->framesize = avio_rl32(pb);
91  avio_skip(pb, 32);
92 
93  hnm->currentframe = 0;
94 
95  if (hnm->width < 256 || hnm->width > 640 ||
96  hnm->height < 150 || hnm->height > 480) {
98  "invalid resolution: %ux%u\n", hnm->width, hnm->height);
99  return AVERROR_INVALIDDATA;
100  }
101 
102  // TODO: find a better way to detect HNM4A
103  if (hnm->width == 640)
104  hnm->version = 0x4a;
105  else
106  hnm->version = 0x40;
107 
108  if (!(vst = avformat_new_stream(s, NULL)))
109  return AVERROR(ENOMEM);
110 
113  vst->codec->codec_tag = 0;
114  vst->codec->width = hnm->width;
115  vst->codec->height = hnm->height;
116  vst->codec->extradata = av_mallocz(1);
117 
118  vst->codec->extradata_size = 1;
119  memcpy(vst->codec->extradata, &hnm->version, 1);
120 
121  vst->start_time = 0;
122 
123  avpriv_set_pts_info(vst, 33, 1, HNM4_FRAME_FPS);
124 
125  return 0;
126 }
127 
129 {
130  Hnm4DemuxContext *hnm = s->priv_data;
131  AVIOContext *pb = s->pb;
132  int ret = 0;
133 
134  uint32_t superchunk_size, chunk_size;
135  uint16_t chunk_id;
136 
137  if (hnm->currentframe == hnm->frames || pb->eof_reached)
138  return AVERROR_EOF;
139 
140  if (hnm->superchunk_remaining == 0) {
141  /* parse next superchunk */
142  superchunk_size = avio_rl24(pb);
143  avio_skip(pb, 1);
144 
145  hnm->superchunk_remaining = superchunk_size - 4;
146  }
147 
148  chunk_size = avio_rl24(pb);
149  avio_skip(pb, 1);
150  chunk_id = avio_rl16(pb);
151  avio_skip(pb, 2);
152 
153  if (chunk_size > hnm->superchunk_remaining || !chunk_size) {
154  av_log(s, AV_LOG_ERROR,
155  "invalid chunk size: %"PRIu32", offset: %"PRId64"\n",
156  chunk_size, avio_tell(pb));
157  avio_skip(pb, hnm->superchunk_remaining - 8);
158  hnm->superchunk_remaining = 0;
159  }
160 
161  switch (chunk_id) {
162  case HNM4_CHUNK_ID_PL:
163  case HNM4_CHUNK_ID_IZ:
164  case HNM4_CHUNK_ID_IU:
165  avio_seek(pb, -8, SEEK_CUR);
166  ret += av_get_packet(pb, pkt, chunk_size);
167  hnm->superchunk_remaining -= chunk_size;
168  if (chunk_id == HNM4_CHUNK_ID_IZ || chunk_id == HNM4_CHUNK_ID_IU)
169  hnm->currentframe++;
170  break;
171 
172  case HNM4_CHUNK_ID_SD:
173  avio_skip(pb, chunk_size - 8);
174  hnm->superchunk_remaining -= chunk_size;
175  break;
176 
177  default:
178  av_log(s, AV_LOG_WARNING, "unknown chunk found: %"PRIu16", offset: %"PRId64"\n",
179  chunk_id, avio_tell(pb));
180  avio_skip(pb, chunk_size - 8);
181  hnm->superchunk_remaining -= chunk_size;
182  break;
183  }
184 
185  return ret;
186 }
187 
189 {
190  Hnm4DemuxContext *hnm = s->priv_data;
191 
192  if (hnm->vpkt.size > 0)
193  av_free_packet(&hnm->vpkt);
194 
195  return 0;
196 }
197 
199  .name = "hnm",
200  .long_name = NULL_IF_CONFIG_SMALL("Cryo HNM v4"),
201  .priv_data_size = sizeof(Hnm4DemuxContext),
207 };