2 * Flash Compatible Streaming Format
3 * Copyright (c) 2000 Fabrice Bellard.
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.
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.
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
21 /* should have a generic way to indicate probable size */
22 #define DUMMY_FILE_SIZE (100 * 1024 * 1024)
23 #define DUMMY_DURATION 600 /* in seconds */
26 #define TAG_SHOWFRAME 1
27 #define TAG_DEFINESHAPE 2
28 #define TAG_FREECHARACTER 3
29 #define TAG_PLACEOBJECT 4
30 #define TAG_REMOVEOBJECT 5
31 #define TAG_STREAMHEAD 18
32 #define TAG_STREAMBLOCK 19
35 #define TAG_LONG 0x100
37 /* flags for shape definition */
38 #define FLAG_MOVETO 0x01
39 #define FLAG_SETFILL0 0x02
40 #define FLAG_SETFILL1 0x04
42 /* character id used */
47 offset_t duration_pos;
52 #ifdef CONFIG_ENCODERS
53 static void put_swf_tag(AVFormatContext *s, int tag)
55 SWFContext *swf = s->priv_data;
56 ByteIOContext *pb = &s->pb;
58 swf->tag_pos = url_ftell(pb);
60 /* reserve some room for the tag */
69 static void put_swf_end_tag(AVFormatContext *s)
71 SWFContext *swf = s->priv_data;
72 ByteIOContext *pb = &s->pb;
77 tag_len = pos - swf->tag_pos - 2;
79 url_fseek(pb, swf->tag_pos, SEEK_SET);
82 put_le16(pb, (tag << 6) | 0x3f);
83 put_le32(pb, tag_len - 4);
85 assert(tag_len < 0x3f);
86 put_le16(pb, (tag << 6) | tag_len);
88 url_fseek(pb, pos, SEEK_SET);
91 static inline void max_nbits(int *nbits_ptr, int val)
107 static void put_swf_rect(ByteIOContext *pb,
108 int xmin, int xmax, int ymin, int ymax)
114 init_put_bits(&p, buf, sizeof(buf));
117 max_nbits(&nbits, xmin);
118 max_nbits(&nbits, xmax);
119 max_nbits(&nbits, ymin);
120 max_nbits(&nbits, ymax);
121 mask = (1 << nbits) - 1;
124 put_bits(&p, 5, nbits);
125 put_bits(&p, nbits, xmin & mask);
126 put_bits(&p, nbits, xmax & mask);
127 put_bits(&p, nbits, ymin & mask);
128 put_bits(&p, nbits, ymax & mask);
131 put_buffer(pb, buf, pbBufPtr(&p) - p.buf);
134 static void put_swf_line_edge(PutBitContext *pb, int dx, int dy)
138 put_bits(pb, 1, 1); /* edge */
139 put_bits(pb, 1, 1); /* line select */
141 max_nbits(&nbits, dx);
142 max_nbits(&nbits, dy);
144 mask = (1 << nbits) - 1;
145 put_bits(pb, 4, nbits - 2); /* 16 bits precision */
149 put_bits(pb, nbits, dy & mask);
150 } else if (dy == 0) {
153 put_bits(pb, nbits, dx & mask);
156 put_bits(pb, nbits, dx & mask);
157 put_bits(pb, nbits, dy & mask);
163 /* put matrix (not size optimized */
164 static void put_swf_matrix(ByteIOContext *pb,
165 int a, int b, int c, int d, int tx, int ty)
170 init_put_bits(&p, buf, sizeof(buf));
172 put_bits(&p, 1, 1); /* a, d present */
173 put_bits(&p, 5, 20); /* nb bits */
177 put_bits(&p, 1, 1); /* b, c present */
178 put_bits(&p, 5, 20); /* nb bits */
182 put_bits(&p, 5, 20); /* nb bits */
183 put_bits(&p, 20, tx);
184 put_bits(&p, 20, ty);
187 put_buffer(pb, buf, pbBufPtr(&p) - p.buf);
190 /* XXX: handle audio only */
191 static int swf_write_header(AVFormatContext *s)
194 ByteIOContext *pb = &s->pb;
195 AVCodecContext *enc, *audio_enc, *video_enc;
198 int i, width, height, rate, rate_base;
200 swf = av_malloc(sizeof(SWFContext));
207 for(i=0;i<s->nb_streams;i++) {
208 enc = &s->streams[i]->codec;
209 if (enc->codec_type == CODEC_TYPE_AUDIO)
216 /* currenty, cannot work correctly if audio only */
222 width = video_enc->width;
223 height = video_enc->height;
224 rate = video_enc->frame_rate;
225 rate_base = video_enc->frame_rate_base;
229 put_byte(pb, 4); /* version (should use 4 for mpeg audio support) */
230 put_le32(pb, DUMMY_FILE_SIZE); /* dummy size
231 (will be patched if not streamed) */
233 put_swf_rect(pb, 0, width, 0, height);
234 put_le16(pb, (rate * 256) / rate_base); /* frame rate */
235 swf->duration_pos = url_ftell(pb);
236 put_le16(pb, (uint16_t)(DUMMY_DURATION * (int64_t)rate / rate_base)); /* frame count */
238 /* define a shape with the jpeg inside */
240 put_swf_tag(s, TAG_DEFINESHAPE);
242 put_le16(pb, SHAPE_ID); /* ID of shape */
243 /* bounding rectangle */
244 put_swf_rect(pb, 0, width, 0, height);
246 put_byte(pb, 1); /* one fill style */
247 put_byte(pb, 0x41); /* clipped bitmap fill */
248 put_le16(pb, BITMAP_ID); /* bitmap ID */
249 /* position of the bitmap */
250 put_swf_matrix(pb, (int)(1.0 * (1 << FRAC_BITS)), 0,
251 0, (int)(1.0 * (1 << FRAC_BITS)), 0, 0);
252 put_byte(pb, 0); /* no line style */
255 init_put_bits(&p, buf1, sizeof(buf1));
256 put_bits(&p, 4, 1); /* one fill bit */
257 put_bits(&p, 4, 0); /* zero line bit */
259 put_bits(&p, 1, 0); /* not an edge */
260 put_bits(&p, 5, FLAG_MOVETO | FLAG_SETFILL0);
261 put_bits(&p, 5, 1); /* nbits */
262 put_bits(&p, 1, 0); /* X */
263 put_bits(&p, 1, 0); /* Y */
264 put_bits(&p, 1, 1); /* set fill style 1 */
266 /* draw the rectangle ! */
267 put_swf_line_edge(&p, width, 0);
268 put_swf_line_edge(&p, 0, height);
269 put_swf_line_edge(&p, -width, 0);
270 put_swf_line_edge(&p, 0, -height);
273 put_bits(&p, 1, 0); /* not an edge */
277 put_buffer(pb, buf1, pbBufPtr(&p) - p.buf);
288 switch(audio_enc->sample_rate) {
303 if (audio_enc->channels == 2)
305 v |= 0x20; /* mp3 compressed */
306 v |= 0x02; /* 16 bits */
308 put_swf_tag(s, TAG_STREAMHEAD);
311 put_le16(&s->pb, (audio_enc->sample_rate * rate_base) / rate); /* avg samples per frame */
317 put_flush_packet(&s->pb);
321 static int swf_write_video(AVFormatContext *s,
322 AVCodecContext *enc, const uint8_t *buf, int size)
324 ByteIOContext *pb = &s->pb;
325 static int tag_id = 0;
327 if (enc->frame_number > 1) {
328 /* remove the shape */
329 put_swf_tag(s, TAG_REMOVEOBJECT);
330 put_le16(pb, SHAPE_ID); /* shape ID */
331 put_le16(pb, 1); /* depth */
334 /* free the bitmap */
335 put_swf_tag(s, TAG_FREECHARACTER);
336 put_le16(pb, BITMAP_ID);
340 put_swf_tag(s, TAG_JPEG2 | TAG_LONG);
342 put_le16(pb, tag_id); /* ID of the image */
344 /* a dummy jpeg header seems to be required */
349 /* write the jpeg image */
350 put_buffer(pb, buf, size);
356 put_swf_tag(s, TAG_PLACEOBJECT);
357 put_le16(pb, SHAPE_ID); /* shape ID */
358 put_le16(pb, 1); /* depth */
359 put_swf_matrix(pb, 1 << FRAC_BITS, 0, 0, 1 << FRAC_BITS, 0, 0);
362 /* output the frame */
363 put_swf_tag(s, TAG_SHOWFRAME);
366 put_flush_packet(&s->pb);
370 static int swf_write_audio(AVFormatContext *s, const uint8_t *buf, int size)
372 ByteIOContext *pb = &s->pb;
374 put_swf_tag(s, TAG_STREAMBLOCK | TAG_LONG);
376 put_buffer(pb, buf, size);
379 put_flush_packet(&s->pb);
383 static int swf_write_packet(AVFormatContext *s, int stream_index,
384 const uint8_t *buf, int size, int64_t pts)
386 AVCodecContext *codec = &s->streams[stream_index]->codec;
387 if (codec->codec_type == CODEC_TYPE_AUDIO)
388 return swf_write_audio(s, buf, size);
390 return swf_write_video(s, codec, buf, size);
393 static int swf_write_trailer(AVFormatContext *s)
395 SWFContext *swf = s->priv_data;
396 ByteIOContext *pb = &s->pb;
397 AVCodecContext *enc, *video_enc;
401 for(i=0;i<s->nb_streams;i++) {
402 enc = &s->streams[i]->codec;
403 if (enc->codec_type == CODEC_TYPE_VIDEO)
407 put_swf_tag(s, TAG_END);
410 put_flush_packet(&s->pb);
412 /* patch file size and number of frames if not streamed */
413 if (!url_is_streamed(&s->pb) && video_enc) {
414 file_size = url_ftell(pb);
415 url_fseek(pb, 4, SEEK_SET);
416 put_le32(pb, file_size);
417 url_fseek(pb, swf->duration_pos, SEEK_SET);
418 put_le16(pb, video_enc->frame_number);
422 #endif //CONFIG_ENCODERS
424 /***********************************/
425 /* just to extract MP3 from swf */
427 static int get_swf_tag(ByteIOContext *pb, int *len_ptr)
445 static int swf_probe(AVProbeData *p)
447 /* check file header */
448 if (p->buf_size <= 16)
450 if (p->buf[0] == 'F' && p->buf[1] == 'W' &&
452 return AVPROBE_SCORE_MAX;
457 static int swf_read_header(AVFormatContext *s, AVFormatParameters *ap)
459 ByteIOContext *pb = &s->pb;
460 int nbits, len, frame_rate, tag, v;
463 if ((get_be32(pb) & 0xffffff00) != MKBETAG('F', 'W', 'S', 0))
466 /* skip rectangle size */
467 nbits = get_byte(pb) >> 3;
468 len = (4 * nbits - 3 + 7) / 8;
470 frame_rate = get_le16(pb);
471 get_le16(pb); /* frame count */
474 tag = get_swf_tag(pb, &len);
476 fprintf(stderr, "No streaming found in SWF\n");
479 if (tag == TAG_STREAMHEAD) {
480 /* streaming found */
484 /* if mp3 streaming found, OK */
485 if ((v & 0x20) != 0) {
486 st = av_new_stream(s, 0);
491 st->codec.channels = 2;
493 st->codec.channels = 1;
495 switch((v>> 2) & 0x03) {
497 st->codec.sample_rate = 11025;
500 st->codec.sample_rate = 22050;
503 st->codec.sample_rate = 44100;
509 st->codec.codec_type = CODEC_TYPE_AUDIO;
510 st->codec.codec_id = CODEC_ID_MP2;
521 static int swf_read_packet(AVFormatContext *s, AVPacket *pkt)
523 ByteIOContext *pb = &s->pb;
527 tag = get_swf_tag(pb, &len);
530 if (tag == TAG_STREAMBLOCK) {
531 av_new_packet(pkt, len);
532 get_buffer(pb, pkt->data, pkt->size);
541 static int swf_read_close(AVFormatContext *s)
546 static AVInputFormat swf_iformat = {
556 #ifdef CONFIG_ENCODERS
557 static AVOutputFormat swf_oformat = {
560 "application/x-shockwave-flash",
569 #endif //CONFIG_ENCODERS
573 av_register_input_format(&swf_iformat);
574 #ifdef CONFIG_ENCODERS
575 av_register_output_format(&swf_oformat);
576 #endif //CONFIG_ENCODERS