nuv.c
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1 /*
2  * NuppelVideo demuxer.
3  * Copyright (c) 2006 Reimar Doeffinger
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavutil/intreadwrite.h"
23 #include "libavutil/intfloat.h"
24 #include "avformat.h"
25 #include "internal.h"
26 #include "riff.h"
27 
28 typedef struct {
29  int v_id;
30  int a_id;
32 } NUVContext;
33 
34 typedef enum {
35  NUV_VIDEO = 'V',
37  NUV_AUDIO = 'A',
38  NUV_SEEKP = 'R',
41 
42 static int nuv_probe(AVProbeData *p) {
43  if (!memcmp(p->buf, "NuppelVideo", 12))
44  return AVPROBE_SCORE_MAX;
45  if (!memcmp(p->buf, "MythTVVideo", 12))
46  return AVPROBE_SCORE_MAX;
47  return 0;
48 }
49 
51 #define PKTSIZE(s) (s & 0xffffff)
52 
60 static int get_codec_data(AVIOContext *pb, AVStream *vst,
61  AVStream *ast, int myth) {
62  nuv_frametype frametype;
63  if (!vst && !myth)
64  return 1; // no codec data needed
65  while (!pb->eof_reached) {
66  int size, subtype;
67  frametype = avio_r8(pb);
68  switch (frametype) {
69  case NUV_EXTRADATA:
70  subtype = avio_r8(pb);
71  avio_skip(pb, 6);
72  size = PKTSIZE(avio_rl32(pb));
73  if (vst && subtype == 'R') {
74  vst->codec->extradata_size = size;
75  vst->codec->extradata = av_malloc(size);
76  avio_read(pb, vst->codec->extradata, size);
77  size = 0;
78  if (!myth)
79  return 1;
80  }
81  break;
82  case NUV_MYTHEXT:
83  avio_skip(pb, 7);
84  size = PKTSIZE(avio_rl32(pb));
85  if (size != 128 * 4)
86  break;
87  avio_rl32(pb); // version
88  if (vst) {
89  vst->codec->codec_tag = avio_rl32(pb);
90  vst->codec->codec_id =
92  if (vst->codec->codec_tag == MKTAG('R', 'J', 'P', 'G'))
93  vst->codec->codec_id = CODEC_ID_NUV;
94  } else
95  avio_skip(pb, 4);
96 
97  if (ast) {
98  ast->codec->codec_tag = avio_rl32(pb);
99  ast->codec->sample_rate = avio_rl32(pb);
101  ast->codec->channels = avio_rl32(pb);
102  ast->codec->codec_id =
106  } else
107  avio_skip(pb, 4 * 4);
108 
109  size -= 6 * 4;
110  avio_skip(pb, size);
111  return 1;
112  case NUV_SEEKP:
113  size = 11;
114  break;
115  default:
116  avio_skip(pb, 7);
117  size = PKTSIZE(avio_rl32(pb));
118  break;
119  }
120  avio_skip(pb, size);
121  }
122  return 0;
123 }
124 
126  NUVContext *ctx = s->priv_data;
127  AVIOContext *pb = s->pb;
128  char id_string[12];
129  double aspect, fps;
130  int is_mythtv, width, height, v_packs, a_packs;
131  int stream_nr = 0;
132  AVStream *vst = NULL, *ast = NULL;
133  avio_read(pb, id_string, 12);
134  is_mythtv = !memcmp(id_string, "MythTVVideo", 12);
135  avio_skip(pb, 5); // version string
136  avio_skip(pb, 3); // padding
137  width = avio_rl32(pb);
138  height = avio_rl32(pb);
139  avio_rl32(pb); // unused, "desiredwidth"
140  avio_rl32(pb); // unused, "desiredheight"
141  avio_r8(pb); // 'P' == progressive, 'I' == interlaced
142  avio_skip(pb, 3); // padding
143  aspect = av_int2double(avio_rl64(pb));
144  if (aspect > 0.9999 && aspect < 1.0001)
145  aspect = 4.0 / 3.0;
146  fps = av_int2double(avio_rl64(pb));
147 
148  // number of packets per stream type, -1 means unknown, e.g. streaming
149  v_packs = avio_rl32(pb);
150  a_packs = avio_rl32(pb);
151  avio_rl32(pb); // text
152 
153  avio_rl32(pb); // keyframe distance (?)
154 
155  if (v_packs) {
156  ctx->v_id = stream_nr++;
157  vst = avformat_new_stream(s, NULL);
158  if (!vst)
159  return AVERROR(ENOMEM);
161  vst->codec->codec_id = CODEC_ID_NUV;
162  vst->codec->width = width;
163  vst->codec->height = height;
164  vst->codec->bits_per_coded_sample = 10;
165  vst->sample_aspect_ratio = av_d2q(aspect * height / width, 10000);
166  vst->r_frame_rate = av_d2q(fps, 60000);
167  avpriv_set_pts_info(vst, 32, 1, 1000);
168  } else
169  ctx->v_id = -1;
170 
171  if (a_packs) {
172  ctx->a_id = stream_nr++;
173  ast = avformat_new_stream(s, NULL);
174  if (!ast)
175  return AVERROR(ENOMEM);
176  ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;
177  ast->codec->codec_id = CODEC_ID_PCM_S16LE;
178  ast->codec->channels = 2;
179  ast->codec->sample_rate = 44100;
180  ast->codec->bit_rate = 2 * 2 * 44100 * 8;
181  ast->codec->block_align = 2 * 2;
182  ast->codec->bits_per_coded_sample = 16;
183  avpriv_set_pts_info(ast, 32, 1, 1000);
184  } else
185  ctx->a_id = -1;
186 
187  get_codec_data(pb, vst, ast, is_mythtv);
188  ctx->rtjpg_video = vst && vst->codec->codec_id == CODEC_ID_NUV;
189  return 0;
190 }
191 
192 #define HDRSIZE 12
193 
194 static int nuv_packet(AVFormatContext *s, AVPacket *pkt) {
195  NUVContext *ctx = s->priv_data;
196  AVIOContext *pb = s->pb;
197  uint8_t hdr[HDRSIZE];
198  nuv_frametype frametype;
199  int ret, size;
200  while (!pb->eof_reached) {
201  int copyhdrsize = ctx->rtjpg_video ? HDRSIZE : 0;
202  uint64_t pos = avio_tell(pb);
203  ret = avio_read(pb, hdr, HDRSIZE);
204  if (ret < HDRSIZE)
205  return ret < 0 ? ret : AVERROR(EIO);
206  frametype = hdr[0];
207  size = PKTSIZE(AV_RL32(&hdr[8]));
208  switch (frametype) {
209  case NUV_EXTRADATA:
210  if (!ctx->rtjpg_video) {
211  avio_skip(pb, size);
212  break;
213  }
214  case NUV_VIDEO:
215  if (ctx->v_id < 0) {
216  av_log(s, AV_LOG_ERROR, "Video packet in file without video stream!\n");
217  avio_skip(pb, size);
218  break;
219  }
220  ret = av_new_packet(pkt, copyhdrsize + size);
221  if (ret < 0)
222  return ret;
223  // HACK: we have no idea if it is a keyframe,
224  // but if we mark none seeking will not work at all.
225  pkt->flags |= AV_PKT_FLAG_KEY;
226  pkt->pos = pos;
227  pkt->pts = AV_RL32(&hdr[4]);
228  pkt->stream_index = ctx->v_id;
229  memcpy(pkt->data, hdr, copyhdrsize);
230  ret = avio_read(pb, pkt->data + copyhdrsize, size);
231  if (ret < 0) {
232  av_free_packet(pkt);
233  return ret;
234  }
235  if (ret < size)
236  av_shrink_packet(pkt, copyhdrsize + ret);
237  return 0;
238  case NUV_AUDIO:
239  if (ctx->a_id < 0) {
240  av_log(s, AV_LOG_ERROR, "Audio packet in file without audio stream!\n");
241  avio_skip(pb, size);
242  break;
243  }
244  ret = av_get_packet(pb, pkt, size);
245  pkt->flags |= AV_PKT_FLAG_KEY;
246  pkt->pos = pos;
247  pkt->pts = AV_RL32(&hdr[4]);
248  pkt->stream_index = ctx->a_id;
249  if (ret < 0) return ret;
250  return 0;
251  case NUV_SEEKP:
252  // contains no data, size value is invalid
253  break;
254  default:
255  avio_skip(pb, size);
256  break;
257  }
258  }
259  return AVERROR(EIO);
260 }
261 
263  .name = "nuv",
264  .long_name = NULL_IF_CONFIG_SMALL("NuppelVideo format"),
265  .priv_data_size = sizeof(NUVContext),
270 };