changing AVCodecContext codec -> *codec in AVStream so additions to AVCodecContext...
[libav.git] / libavformat / sierravmd.c
1 /*
2 * Sierra VMD Format Demuxer
3 * Copyright (c) 2004 The ffmpeg Project
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19
20 /**
21 * @file sierravmd.c
22 * Sierra VMD file demuxer
23 * by Vladimir "VAG" Gneushev (vagsoft at mail.ru)
24 * for more information on the Sierra VMD file format, visit:
25 * http://www.pcisys.net/~melanson/codecs/
26 */
27
28 #include "avformat.h"
29
30 #define VMD_HEADER_SIZE 0x0330
31 #define BYTES_PER_FRAME_RECORD 16
32
33 typedef struct {
34 int stream_index;
35 offset_t frame_offset;
36 unsigned int frame_size;
37 int64_t pts;
38 int keyframe;
39 unsigned char frame_record[BYTES_PER_FRAME_RECORD];
40 } vmd_frame_t;
41
42 typedef struct VmdDemuxContext {
43 int video_stream_index;
44 int audio_stream_index;
45
46 unsigned int audio_type;
47 unsigned int audio_samplerate;
48 unsigned int audio_bits;
49 unsigned int audio_channels;
50
51 unsigned int frame_count;
52 vmd_frame_t *frame_table;
53 unsigned int current_frame;
54
55 int sample_rate;
56 int64_t audio_sample_counter;
57 int audio_frame_divisor;
58 int audio_block_align;
59
60 unsigned char vmd_header[VMD_HEADER_SIZE];
61 } VmdDemuxContext;
62
63 static int vmd_probe(AVProbeData *p)
64 {
65 if (p->buf_size < 2)
66 return 0;
67
68 /* check if the first 2 bytes of the file contain the appropriate size
69 * of a VMD header chunk */
70 if (LE_16(&p->buf[0]) != VMD_HEADER_SIZE - 2)
71 return 0;
72
73 /* only return half certainty since this check is a bit sketchy */
74 return AVPROBE_SCORE_MAX / 2;
75 }
76
77 /* This is a support function to determine the duration, in sample
78 * frames, of a particular audio chunk, taking into account silent
79 * encodings. */
80 static int vmd_calculate_audio_duration(unsigned char *audio_chunk,
81 int audio_chunk_size, int block_align)
82 {
83 unsigned char *p = audio_chunk + 16;
84 unsigned char *p_end = audio_chunk + audio_chunk_size;
85 int total_samples = 0;
86 unsigned int sound_flags;
87
88 if (audio_chunk_size < 16)
89 return 0;
90
91 sound_flags = LE_32(p);
92 p += 4;
93 while (p < p_end) {
94 total_samples += block_align;
95 if ((sound_flags & 0x01) == 0)
96 p += block_align;
97 sound_flags >>= 1;
98 }
99
100 return total_samples;
101 }
102
103 static int vmd_read_header(AVFormatContext *s,
104 AVFormatParameters *ap)
105 {
106 VmdDemuxContext *vmd = (VmdDemuxContext *)s->priv_data;
107 ByteIOContext *pb = &s->pb;
108 AVStream *st;
109 unsigned int toc_offset;
110 unsigned char *raw_frame_table;
111 int raw_frame_table_size;
112 unsigned char *current_frame_record;
113 offset_t current_offset;
114 int i;
115 unsigned int total_frames;
116 int64_t video_pts_inc;
117 int64_t current_video_pts = 0;
118
119 /* fetch the main header, including the 2 header length bytes */
120 url_fseek(pb, 0, SEEK_SET);
121 if (get_buffer(pb, vmd->vmd_header, VMD_HEADER_SIZE) != VMD_HEADER_SIZE)
122 return AVERROR_IO;
123
124 vmd->audio_sample_counter = 0;
125 vmd->audio_frame_divisor = 1;
126 vmd->audio_block_align = 1;
127
128 /* start up the decoders */
129 st = av_new_stream(s, 0);
130 if (!st)
131 return AVERROR_NOMEM;
132 av_set_pts_info(st, 33, 1, 90000);
133 vmd->video_stream_index = st->index;
134 st->codec->codec_type = CODEC_TYPE_VIDEO;
135 st->codec->codec_id = CODEC_ID_VMDVIDEO;
136 st->codec->codec_tag = 0; /* no fourcc */
137 st->codec->width = LE_16(&vmd->vmd_header[12]);
138 st->codec->height = LE_16(&vmd->vmd_header[14]);
139 st->codec->extradata_size = VMD_HEADER_SIZE;
140 st->codec->extradata = av_malloc(VMD_HEADER_SIZE);
141 memcpy(st->codec->extradata, vmd->vmd_header, VMD_HEADER_SIZE);
142
143 /* if sample rate is 0, assume no audio */
144 vmd->sample_rate = LE_16(&vmd->vmd_header[804]);
145 if (vmd->sample_rate) {
146 st = av_new_stream(s, 0);
147 if (!st)
148 return AVERROR_NOMEM;
149 av_set_pts_info(st, 33, 1, 90000);
150 vmd->audio_stream_index = st->index;
151 st->codec->codec_type = CODEC_TYPE_AUDIO;
152 st->codec->codec_id = CODEC_ID_VMDAUDIO;
153 st->codec->codec_tag = 0; /* no codec tag */
154 st->codec->channels = (vmd->vmd_header[811] & 0x80) ? 2 : 1;
155 st->codec->sample_rate = vmd->sample_rate;
156 st->codec->block_align = vmd->audio_block_align =
157 LE_16(&vmd->vmd_header[806]);
158 if (st->codec->block_align & 0x8000) {
159 st->codec->bits_per_sample = 16;
160 st->codec->block_align = -(st->codec->block_align - 0x10000);
161 } else
162 st->codec->bits_per_sample = 16;
163 // st->codec->bits_per_sample = 8;
164 st->codec->bit_rate = st->codec->sample_rate *
165 st->codec->bits_per_sample * st->codec->channels;
166
167 /* for calculating pts */
168 vmd->audio_frame_divisor = st->codec->bits_per_sample / 8 /
169 st->codec->channels;
170
171 video_pts_inc = 90000;
172 video_pts_inc *= st->codec->block_align;
173 video_pts_inc /= st->codec->sample_rate;
174 } else {
175 /* if no audio, assume 10 frames/second */
176 video_pts_inc = 90000 / 10;
177 }
178
179 /* skip over the offset table and load the table of contents; don't
180 * care about the offset table since demuxer will calculate those
181 * independently */
182 toc_offset = LE_32(&vmd->vmd_header[812]);
183 vmd->frame_count = LE_16(&vmd->vmd_header[6]);
184 url_fseek(pb, toc_offset + vmd->frame_count * 6, SEEK_SET);
185
186 /* each on-disk VMD frame has an audio part and a video part; demuxer
187 * accounts them separately */
188 if(vmd->sample_rate)
189 vmd->frame_count *= 2;
190 raw_frame_table = NULL;
191 vmd->frame_table = NULL;
192 raw_frame_table_size = vmd->frame_count * BYTES_PER_FRAME_RECORD;
193 raw_frame_table = av_malloc(raw_frame_table_size);
194 vmd->frame_table = av_malloc(vmd->frame_count * sizeof(vmd_frame_t));
195 if (!raw_frame_table || !vmd->frame_table) {
196 av_free(raw_frame_table);
197 av_free(vmd->frame_table);
198 return AVERROR_NOMEM;
199 }
200 if (get_buffer(pb, raw_frame_table, raw_frame_table_size) !=
201 raw_frame_table_size) {
202 av_free(raw_frame_table);
203 av_free(vmd->frame_table);
204 return AVERROR_IO;
205 }
206
207 current_offset = LE_32(&vmd->vmd_header[20]);
208 current_frame_record = raw_frame_table;
209 total_frames = vmd->frame_count;
210 i = 0;
211 while (total_frames--) {
212
213 /* if the frame size is 0, do not count the frame and bring the
214 * total frame count down */
215 // note, we limit the size to 1Gb to ensure that we dont end up overflowing the size integer used to allocate the memory
216 vmd->frame_table[i].frame_size = LE_32(&current_frame_record[2]) & 0x3FFFFFFF;
217
218 /* this logic is present so that 0-length audio chunks are not
219 * accounted */
220 if (!vmd->frame_table[i].frame_size) {
221 vmd->frame_count--; /* one less frame to count */
222 current_frame_record += BYTES_PER_FRAME_RECORD;
223 continue;
224 }
225
226 if (current_frame_record[0] == 0x02)
227 vmd->frame_table[i].stream_index = vmd->video_stream_index;
228 else
229 vmd->frame_table[i].stream_index = vmd->audio_stream_index;
230 vmd->frame_table[i].frame_offset = current_offset;
231 current_offset += vmd->frame_table[i].frame_size;
232 memcpy(vmd->frame_table[i].frame_record, current_frame_record,
233 BYTES_PER_FRAME_RECORD);
234
235 /* figure out the pts for this frame */
236 if (current_frame_record[0] == 0x02) {
237 vmd->frame_table[i].pts = current_video_pts;
238 current_video_pts += video_pts_inc;
239 } else if (current_frame_record[0] == 0x01) {
240 /* figure out the pts during the dispatch phase */
241 vmd->frame_table[i].pts = 0;
242 }
243
244 current_frame_record += BYTES_PER_FRAME_RECORD;
245 i++;
246 }
247
248 av_free(raw_frame_table);
249
250 vmd->current_frame = 0;
251
252 return 0;
253 }
254
255 static int vmd_read_packet(AVFormatContext *s,
256 AVPacket *pkt)
257 {
258 VmdDemuxContext *vmd = (VmdDemuxContext *)s->priv_data;
259 ByteIOContext *pb = &s->pb;
260 int ret = 0;
261 vmd_frame_t *frame;
262
263 if (vmd->current_frame >= vmd->frame_count)
264 return AVERROR_IO;
265
266 frame = &vmd->frame_table[vmd->current_frame];
267 /* position the stream (will probably be there already) */
268 url_fseek(pb, frame->frame_offset, SEEK_SET);
269
270 if (av_new_packet(pkt, frame->frame_size + BYTES_PER_FRAME_RECORD))
271 return AVERROR_NOMEM;
272 pkt->pos= url_ftell(pb);
273 memcpy(pkt->data, frame->frame_record, BYTES_PER_FRAME_RECORD);
274 ret = get_buffer(pb, pkt->data + BYTES_PER_FRAME_RECORD,
275 frame->frame_size);
276
277 if (ret != frame->frame_size) {
278 av_free_packet(pkt);
279 ret = AVERROR_IO;
280 }
281 pkt->stream_index = frame->stream_index;
282 if (frame->frame_record[0] == 0x02)
283 pkt->pts = frame->pts;
284 else {
285 pkt->pts = vmd->audio_sample_counter;
286 pkt->pts *= 90000;
287 pkt->pts /= vmd->sample_rate;
288 // pkt->pts /= vmd->audio_frame_divisor;
289 vmd->audio_sample_counter += vmd_calculate_audio_duration(
290 pkt->data, pkt->size, vmd->audio_block_align);
291
292 }
293 av_log(NULL, AV_LOG_INFO, " dispatching %s frame with %d bytes and pts %lld (%0.1f sec)\n",
294 (frame->frame_record[0] == 0x02) ? "video" : "audio",
295 frame->frame_size + BYTES_PER_FRAME_RECORD,
296 pkt->pts, (float)(pkt->pts / 90000.0));
297
298 vmd->current_frame++;
299
300 return ret;
301 }
302
303 static int vmd_read_close(AVFormatContext *s)
304 {
305 VmdDemuxContext *vmd = (VmdDemuxContext *)s->priv_data;
306
307 av_free(vmd->frame_table);
308
309 return 0;
310 }
311
312 static AVInputFormat vmd_iformat = {
313 "vmd",
314 "Sierra VMD format",
315 sizeof(VmdDemuxContext),
316 vmd_probe,
317 vmd_read_header,
318 vmd_read_packet,
319 vmd_read_close,
320 };
321
322 int vmd_init(void)
323 {
324 av_register_input_format(&vmd_iformat);
325 return 0;
326 }