FFmpeg
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
tiertexseq.c
Go to the documentation of this file.
1 /*
2  * Tiertex Limited SEQ File Demuxer
3  * Copyright (c) 2006 Gregory Montoir (cyx@users.sourceforge.net)
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 
22 /**
23  * @file
24  * Tiertex Limited SEQ file demuxer
25  */
26 
28 #include "avformat.h"
29 #include "internal.h"
30 
31 #define SEQ_FRAME_SIZE 6144
32 #define SEQ_FRAME_W 256
33 #define SEQ_FRAME_H 128
34 #define SEQ_NUM_FRAME_BUFFERS 30
35 #define SEQ_AUDIO_BUFFER_SIZE 882
36 #define SEQ_SAMPLE_RATE 22050
37 #define SEQ_FRAME_RATE 25
38 
39 
40 typedef struct TiertexSeqFrameBuffer {
41  int fill_size;
42  int data_size;
43  unsigned char *data;
45 
46 typedef struct SeqDemuxContext {
55  unsigned int current_pal_data_size;
56  unsigned int current_pal_data_offs;
58  unsigned char *current_video_data_ptr;
61 
62 
63 static int seq_probe(AVProbeData *p)
64 {
65  int i;
66 
67  if (p->buf_size < 258)
68  return 0;
69 
70  /* there's no real header in a .seq file, the only thing they have in common */
71  /* is the first 256 bytes of the file which are always filled with 0 */
72  for (i = 0; i < 256; i++)
73  if (p->buf[i])
74  return 0;
75 
76  if(p->buf[256]==0 && p->buf[257]==0)
77  return 0;
78 
79  /* only one fourth of the score since the previous check is too naive */
80  return AVPROBE_SCORE_MAX / 4;
81 }
82 
84 {
85  int i, sz;
86  TiertexSeqFrameBuffer *seq_buffer;
87 
88  avio_seek(pb, 256, SEEK_SET);
89 
90  for (i = 0; i < SEQ_NUM_FRAME_BUFFERS; i++) {
91  sz = avio_rl16(pb);
92  if (sz == 0)
93  break;
94  else {
95  seq_buffer = &seq->frame_buffers[i];
96  seq_buffer->fill_size = 0;
97  seq_buffer->data_size = sz;
98  seq_buffer->data = av_malloc(sz);
99  if (!seq_buffer->data)
100  return AVERROR(ENOMEM);
101  }
102  }
103  seq->frame_buffers_count = i;
104  return 0;
105 }
106 
107 static int seq_fill_buffer(SeqDemuxContext *seq, AVIOContext *pb, int buffer_num, unsigned int data_offs, int data_size)
108 {
109  TiertexSeqFrameBuffer *seq_buffer;
110 
111  if (buffer_num >= SEQ_NUM_FRAME_BUFFERS)
112  return AVERROR_INVALIDDATA;
113 
114  seq_buffer = &seq->frame_buffers[buffer_num];
115  if (seq_buffer->fill_size + data_size > seq_buffer->data_size || data_size <= 0)
116  return AVERROR_INVALIDDATA;
117 
118  avio_seek(pb, seq->current_frame_offs + data_offs, SEEK_SET);
119  if (avio_read(pb, seq_buffer->data + seq_buffer->fill_size, data_size) != data_size)
120  return AVERROR(EIO);
121 
122  seq_buffer->fill_size += data_size;
123  return 0;
124 }
125 
127 {
128  unsigned int offset_table[4], buffer_num[4];
129  TiertexSeqFrameBuffer *seq_buffer;
130  int i, e, err;
131 
133  avio_seek(pb, seq->current_frame_offs, SEEK_SET);
134 
135  /* sound data */
137  if (seq->current_audio_data_offs) {
139  } else {
140  seq->current_audio_data_size = 0;
141  }
142 
143  /* palette data */
144  seq->current_pal_data_offs = avio_rl16(pb);
145  if (seq->current_pal_data_offs) {
146  seq->current_pal_data_size = 768;
147  } else {
148  seq->current_pal_data_size = 0;
149  }
150 
151  /* video data */
152  for (i = 0; i < 4; i++)
153  buffer_num[i] = avio_r8(pb);
154 
155  for (i = 0; i < 4; i++)
156  offset_table[i] = avio_rl16(pb);
157 
158  for (i = 0; i < 3; i++) {
159  if (offset_table[i]) {
160  for (e = i + 1; e < 3 && offset_table[e] == 0; e++);
161  err = seq_fill_buffer(seq, pb, buffer_num[1 + i],
162  offset_table[i],
163  offset_table[e] - offset_table[i]);
164  if (err)
165  return err;
166  }
167  }
168 
169  if (buffer_num[0] != 255) {
170  if (buffer_num[0] >= SEQ_NUM_FRAME_BUFFERS)
171  return AVERROR_INVALIDDATA;
172 
173  seq_buffer = &seq->frame_buffers[buffer_num[0]];
174  seq->current_video_data_size = seq_buffer->fill_size;
175  seq->current_video_data_ptr = seq_buffer->data;
176  seq_buffer->fill_size = 0;
177  } else {
178  seq->current_video_data_size = 0;
179  seq->current_video_data_ptr = 0;
180  }
181 
182  return 0;
183 }
184 
186 {
187  int i, rc;
188  SeqDemuxContext *seq = s->priv_data;
189  AVIOContext *pb = s->pb;
190  AVStream *st;
191 
192  /* init internal buffers */
193  rc = seq_init_frame_buffers(seq, pb);
194  if (rc)
195  return rc;
196 
197  seq->current_frame_offs = 0;
198 
199  /* preload (no audio data, just buffer operations related data) */
200  for (i = 1; i <= 100; i++) {
201  rc = seq_parse_frame_data(seq, pb);
202  if (rc)
203  return rc;
204  }
205 
206  seq->current_frame_pts = 0;
207 
208  seq->audio_buffer_full = 0;
209 
210  /* initialize the video decoder stream */
211  st = avformat_new_stream(s, NULL);
212  if (!st)
213  return AVERROR(ENOMEM);
214 
216  seq->video_stream_index = st->index;
219  st->codec->codec_tag = 0; /* no fourcc */
220  st->codec->width = SEQ_FRAME_W;
221  st->codec->height = SEQ_FRAME_H;
222 
223  /* initialize the audio decoder stream */
224  st = avformat_new_stream(s, NULL);
225  if (!st)
226  return AVERROR(ENOMEM);
227 
228  st->start_time = 0;
230  seq->audio_stream_index = st->index;
233  st->codec->codec_tag = 0; /* no tag */
234  st->codec->channels = 1;
237  st->codec->bits_per_coded_sample = 16;
240 
241  return 0;
242 }
243 
245 {
246  int rc;
247  SeqDemuxContext *seq = s->priv_data;
248  AVIOContext *pb = s->pb;
249 
250  if (!seq->audio_buffer_full) {
251  rc = seq_parse_frame_data(seq, pb);
252  if (rc)
253  return rc;
254 
255  /* video packet */
256  if (seq->current_pal_data_size + seq->current_video_data_size != 0) {
258  return AVERROR(ENOMEM);
259 
260  pkt->data[0] = 0;
261  if (seq->current_pal_data_size) {
262  pkt->data[0] |= 1;
263  avio_seek(pb, seq->current_frame_offs + seq->current_pal_data_offs, SEEK_SET);
264  if (avio_read(pb, &pkt->data[1], seq->current_pal_data_size) != seq->current_pal_data_size)
265  return AVERROR(EIO);
266  }
267  if (seq->current_video_data_size) {
268  pkt->data[0] |= 2;
269  memcpy(&pkt->data[1 + seq->current_pal_data_size],
272  }
273  pkt->stream_index = seq->video_stream_index;
274  pkt->pts = seq->current_frame_pts;
275 
276  /* sound buffer will be processed on next read_packet() call */
277  seq->audio_buffer_full = 1;
278  return 0;
279  }
280  }
281 
282  /* audio packet */
283  if (seq->current_audio_data_offs == 0) /* end of data reached */
284  return AVERROR(EIO);
285 
286  avio_seek(pb, seq->current_frame_offs + seq->current_audio_data_offs, SEEK_SET);
287  rc = av_get_packet(pb, pkt, seq->current_audio_data_size);
288  if (rc < 0)
289  return rc;
290 
291  pkt->stream_index = seq->audio_stream_index;
292  seq->current_frame_pts++;
293 
294  seq->audio_buffer_full = 0;
295  return 0;
296 }
297 
299 {
300  int i;
301  SeqDemuxContext *seq = s->priv_data;
302 
303  for (i = 0; i < SEQ_NUM_FRAME_BUFFERS; i++)
304  av_freep(&seq->frame_buffers[i].data);
305 
306  return 0;
307 }
308 
310  .name = "tiertexseq",
311  .long_name = NULL_IF_CONFIG_SMALL("Tiertex Limited SEQ"),
312  .priv_data_size = sizeof(SeqDemuxContext),
317 };