2 * Flash Compatible Streaming Format muxer
3 * Copyright (c) 2000 Fabrice Bellard
4 * Copyright (c) 2003 Tinic Uro
6 * This file is part of Libav.
8 * Libav 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.
13 * Libav 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.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with Libav; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 #include "libavcodec/put_bits.h"
27 static void put_swf_tag(AVFormatContext *s, int tag)
29 SWFContext *swf = s->priv_data;
30 AVIOContext *pb = s->pb;
32 swf->tag_pos = avio_tell(pb);
34 /* reserve some room for the tag */
43 static void put_swf_end_tag(AVFormatContext *s)
45 SWFContext *swf = s->priv_data;
46 AVIOContext *pb = s->pb;
51 tag_len = pos - swf->tag_pos - 2;
53 avio_seek(pb, swf->tag_pos, SEEK_SET);
56 avio_wl16(pb, (tag << 6) | 0x3f);
57 avio_wl32(pb, tag_len - 4);
59 assert(tag_len < 0x3f);
60 avio_wl16(pb, (tag << 6) | tag_len);
62 avio_seek(pb, pos, SEEK_SET);
65 static inline void max_nbits(int *nbits_ptr, int val)
81 static void put_swf_rect(AVIOContext *pb,
82 int xmin, int xmax, int ymin, int ymax)
88 init_put_bits(&p, buf, sizeof(buf));
91 max_nbits(&nbits, xmin);
92 max_nbits(&nbits, xmax);
93 max_nbits(&nbits, ymin);
94 max_nbits(&nbits, ymax);
95 mask = (1 << nbits) - 1;
98 put_bits(&p, 5, nbits);
99 put_bits(&p, nbits, xmin & mask);
100 put_bits(&p, nbits, xmax & mask);
101 put_bits(&p, nbits, ymin & mask);
102 put_bits(&p, nbits, ymax & mask);
105 avio_write(pb, buf, put_bits_ptr(&p) - p.buf);
108 static void put_swf_line_edge(PutBitContext *pb, int dx, int dy)
112 put_bits(pb, 1, 1); /* edge */
113 put_bits(pb, 1, 1); /* line select */
115 max_nbits(&nbits, dx);
116 max_nbits(&nbits, dy);
118 mask = (1 << nbits) - 1;
119 put_bits(pb, 4, nbits - 2); /* 16 bits precision */
123 put_bits(pb, nbits, dy & mask);
124 } else if (dy == 0) {
127 put_bits(pb, nbits, dx & mask);
130 put_bits(pb, nbits, dx & mask);
131 put_bits(pb, nbits, dy & mask);
137 static void put_swf_matrix(AVIOContext *pb,
138 int a, int b, int c, int d, int tx, int ty)
144 init_put_bits(&p, buf, sizeof(buf));
146 put_bits(&p, 1, 1); /* a, d present */
148 max_nbits(&nbits, a);
149 max_nbits(&nbits, d);
150 put_bits(&p, 5, nbits); /* nb bits */
151 put_bits(&p, nbits, a);
152 put_bits(&p, nbits, d);
154 put_bits(&p, 1, 1); /* b, c present */
156 max_nbits(&nbits, c);
157 max_nbits(&nbits, b);
158 put_bits(&p, 5, nbits); /* nb bits */
159 put_bits(&p, nbits, c);
160 put_bits(&p, nbits, b);
163 max_nbits(&nbits, tx);
164 max_nbits(&nbits, ty);
165 put_bits(&p, 5, nbits); /* nb bits */
166 put_bits(&p, nbits, tx);
167 put_bits(&p, nbits, ty);
170 avio_write(pb, buf, put_bits_ptr(&p) - p.buf);
173 static int swf_write_header(AVFormatContext *s)
175 SWFContext *swf = s->priv_data;
176 AVIOContext *pb = s->pb;
179 int i, width, height, rate, rate_base;
182 swf->sound_samples = 0;
183 swf->swf_frame_number = 0;
184 swf->video_frame_number = 0;
186 for(i=0;i<s->nb_streams;i++) {
187 AVCodecContext *enc = s->streams[i]->codec;
188 if (enc->codec_type == AVMEDIA_TYPE_AUDIO) {
189 if (enc->codec_id == CODEC_ID_MP3) {
190 swf->audio_enc = enc;
191 swf->audio_fifo= av_fifo_alloc(AUDIO_FIFO_SIZE);
192 if (!swf->audio_fifo)
193 return AVERROR(ENOMEM);
195 av_log(s, AV_LOG_ERROR, "SWF muxer only supports MP3\n");
199 if (enc->codec_id == CODEC_ID_VP6F ||
200 enc->codec_id == CODEC_ID_FLV1 ||
201 enc->codec_id == CODEC_ID_MJPEG) {
202 swf->video_enc = enc;
204 av_log(s, AV_LOG_ERROR, "SWF muxer only supports VP6, FLV1 and MJPEG\n");
210 if (!swf->video_enc) {
211 /* currently, cannot work correctly if audio only */
217 width = swf->video_enc->width;
218 height = swf->video_enc->height;
219 rate = swf->video_enc->time_base.den;
220 rate_base = swf->video_enc->time_base.num;
224 swf->samples_per_frame = (44100. * rate_base) / rate;
226 swf->samples_per_frame = (swf->audio_enc->sample_rate * rate_base) / rate;
228 avio_write(pb, "FWS", 3);
230 if (!strcmp("avm2", s->oformat->name))
232 else if (swf->video_enc && swf->video_enc->codec_id == CODEC_ID_VP6F)
233 version = 8; /* version 8 and above support VP6 codec */
234 else if (swf->video_enc && swf->video_enc->codec_id == CODEC_ID_FLV1)
235 version = 6; /* version 6 and above support FLV1 codec */
237 version = 4; /* version 4 for mpeg audio support */
238 avio_w8(pb, version);
240 avio_wl32(pb, DUMMY_FILE_SIZE); /* dummy size
241 (will be patched if not streamed) */
243 put_swf_rect(pb, 0, width * 20, 0, height * 20);
244 avio_wl16(pb, (rate * 256) / rate_base); /* frame rate */
245 swf->duration_pos = avio_tell(pb);
246 avio_wl16(pb, (uint16_t)(DUMMY_DURATION * (int64_t)rate / rate_base)); /* frame count */
248 /* avm2/swf v9 (also v8?) files require a file attribute tag */
250 put_swf_tag(s, TAG_FILEATTRIBUTES);
251 avio_wl32(pb, 1<<3); /* set ActionScript v3/AVM2 flag */
255 /* define a shape with the jpeg inside */
256 if (swf->video_enc && swf->video_enc->codec_id == CODEC_ID_MJPEG) {
257 put_swf_tag(s, TAG_DEFINESHAPE);
259 avio_wl16(pb, SHAPE_ID); /* ID of shape */
260 /* bounding rectangle */
261 put_swf_rect(pb, 0, width, 0, height);
263 avio_w8(pb, 1); /* one fill style */
264 avio_w8(pb, 0x41); /* clipped bitmap fill */
265 avio_wl16(pb, BITMAP_ID); /* bitmap ID */
266 /* position of the bitmap */
267 put_swf_matrix(pb, (int)(1.0 * (1 << FRAC_BITS)), 0,
268 0, (int)(1.0 * (1 << FRAC_BITS)), 0, 0);
269 avio_w8(pb, 0); /* no line style */
272 init_put_bits(&p, buf1, sizeof(buf1));
273 put_bits(&p, 4, 1); /* one fill bit */
274 put_bits(&p, 4, 0); /* zero line bit */
276 put_bits(&p, 1, 0); /* not an edge */
277 put_bits(&p, 5, FLAG_MOVETO | FLAG_SETFILL0);
278 put_bits(&p, 5, 1); /* nbits */
279 put_bits(&p, 1, 0); /* X */
280 put_bits(&p, 1, 0); /* Y */
281 put_bits(&p, 1, 1); /* set fill style 1 */
283 /* draw the rectangle ! */
284 put_swf_line_edge(&p, width, 0);
285 put_swf_line_edge(&p, 0, height);
286 put_swf_line_edge(&p, -width, 0);
287 put_swf_line_edge(&p, 0, -height);
290 put_bits(&p, 1, 0); /* not an edge */
294 avio_write(pb, buf1, put_bits_ptr(&p) - p.buf);
299 if (swf->audio_enc && swf->audio_enc->codec_id == CODEC_ID_MP3) {
303 put_swf_tag(s, TAG_STREAMHEAD2);
304 switch(swf->audio_enc->sample_rate) {
305 case 11025: v |= 1 << 2; break;
306 case 22050: v |= 2 << 2; break;
307 case 44100: v |= 3 << 2; break;
310 av_log(s, AV_LOG_ERROR, "swf does not support that sample rate, choose from (44100, 22050, 11025).\n");
313 v |= 0x02; /* 16 bit playback */
314 if (swf->audio_enc->channels == 2)
315 v |= 0x01; /* stereo playback */
317 v |= 0x20; /* mp3 compressed */
319 avio_wl16(s->pb, swf->samples_per_frame); /* avg samples per frame */
329 static int swf_write_video(AVFormatContext *s,
330 AVCodecContext *enc, const uint8_t *buf, int size)
332 SWFContext *swf = s->priv_data;
333 AVIOContext *pb = s->pb;
335 /* Flash Player limit */
336 if (swf->swf_frame_number == 16000)
337 av_log(enc, AV_LOG_INFO, "warning: Flash Player limit of 16000 frames reached\n");
339 if (enc->codec_id == CODEC_ID_VP6F ||
340 enc->codec_id == CODEC_ID_FLV1) {
341 if (swf->video_frame_number == 0) {
342 /* create a new video object */
343 put_swf_tag(s, TAG_VIDEOSTREAM);
344 avio_wl16(pb, VIDEO_ID);
345 swf->vframes_pos = avio_tell(pb);
346 avio_wl16(pb, 15000); /* hard flash player limit */
347 avio_wl16(pb, enc->width);
348 avio_wl16(pb, enc->height);
350 avio_w8(pb,ff_codec_get_tag(swf_codec_tags,enc->codec_id));
353 /* place the video object for the first time */
354 put_swf_tag(s, TAG_PLACEOBJECT2);
357 avio_wl16(pb, VIDEO_ID);
358 put_swf_matrix(pb, 1 << FRAC_BITS, 0, 0, 1 << FRAC_BITS, 0, 0);
359 avio_wl16(pb, swf->video_frame_number);
360 avio_write(pb, "video", 5);
364 /* mark the character for update */
365 put_swf_tag(s, TAG_PLACEOBJECT2);
368 avio_wl16(pb, swf->video_frame_number);
372 /* set video frame data */
373 put_swf_tag(s, TAG_VIDEOFRAME | TAG_LONG);
374 avio_wl16(pb, VIDEO_ID);
375 avio_wl16(pb, swf->video_frame_number++);
376 avio_write(pb, buf, size);
378 } else if (enc->codec_id == CODEC_ID_MJPEG) {
379 if (swf->swf_frame_number > 0) {
380 /* remove the shape */
381 put_swf_tag(s, TAG_REMOVEOBJECT);
382 avio_wl16(pb, SHAPE_ID); /* shape ID */
383 avio_wl16(pb, 1); /* depth */
386 /* free the bitmap */
387 put_swf_tag(s, TAG_FREECHARACTER);
388 avio_wl16(pb, BITMAP_ID);
392 put_swf_tag(s, TAG_JPEG2 | TAG_LONG);
394 avio_wl16(pb, BITMAP_ID); /* ID of the image */
396 /* a dummy jpeg header seems to be required */
397 avio_wb32(pb, 0xffd8ffd9);
398 /* write the jpeg image */
399 avio_write(pb, buf, size);
405 put_swf_tag(s, TAG_PLACEOBJECT);
406 avio_wl16(pb, SHAPE_ID); /* shape ID */
407 avio_wl16(pb, 1); /* depth */
408 put_swf_matrix(pb, 20 << FRAC_BITS, 0, 0, 20 << FRAC_BITS, 0, 0);
412 swf->swf_frame_number++;
414 /* streaming sound always should be placed just before showframe tags */
415 if (swf->audio_enc && av_fifo_size(swf->audio_fifo)) {
416 int frame_size = av_fifo_size(swf->audio_fifo);
417 put_swf_tag(s, TAG_STREAMBLOCK | TAG_LONG);
418 avio_wl16(pb, swf->sound_samples);
419 avio_wl16(pb, 0); // seek samples
420 av_fifo_generic_read(swf->audio_fifo, pb, frame_size, &avio_write);
424 swf->sound_samples = 0;
427 /* output the frame */
428 put_swf_tag(s, TAG_SHOWFRAME);
436 static int swf_write_audio(AVFormatContext *s,
437 AVCodecContext *enc, uint8_t *buf, int size)
439 SWFContext *swf = s->priv_data;
441 /* Flash Player limit */
442 if (swf->swf_frame_number == 16000)
443 av_log(enc, AV_LOG_INFO, "warning: Flash Player limit of 16000 frames reached\n");
445 if (av_fifo_size(swf->audio_fifo) + size > AUDIO_FIFO_SIZE) {
446 av_log(s, AV_LOG_ERROR, "audio fifo too small to mux audio essence\n");
450 av_fifo_generic_write(swf->audio_fifo, buf, size, NULL);
451 swf->sound_samples += av_get_audio_frame_duration(enc, size);
453 /* if audio only stream make sure we add swf frames */
455 swf_write_video(s, enc, 0, 0);
460 static int swf_write_packet(AVFormatContext *s, AVPacket *pkt)
462 AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
463 if (codec->codec_type == AVMEDIA_TYPE_AUDIO)
464 return swf_write_audio(s, codec, pkt->data, pkt->size);
466 return swf_write_video(s, codec, pkt->data, pkt->size);
469 static int swf_write_trailer(AVFormatContext *s)
471 SWFContext *swf = s->priv_data;
472 AVIOContext *pb = s->pb;
473 AVCodecContext *enc, *video_enc;
477 for(i=0;i<s->nb_streams;i++) {
478 enc = s->streams[i]->codec;
479 if (enc->codec_type == AVMEDIA_TYPE_VIDEO)
482 av_fifo_free(swf->audio_fifo);
485 put_swf_tag(s, TAG_END);
490 /* patch file size and number of frames if not streamed */
491 if (s->pb->seekable && video_enc) {
492 file_size = avio_tell(pb);
493 avio_seek(pb, 4, SEEK_SET);
494 avio_wl32(pb, file_size);
495 avio_seek(pb, swf->duration_pos, SEEK_SET);
496 avio_wl16(pb, swf->video_frame_number);
497 avio_seek(pb, swf->vframes_pos, SEEK_SET);
498 avio_wl16(pb, swf->video_frame_number);
499 avio_seek(pb, file_size, SEEK_SET);
505 AVOutputFormat ff_swf_muxer = {
507 .long_name = NULL_IF_CONFIG_SMALL("Flash format"),
508 .mime_type = "application/x-shockwave-flash",
510 .priv_data_size = sizeof(SWFContext),
511 .audio_codec = CODEC_ID_MP3,
512 .video_codec = CODEC_ID_FLV1,
513 .write_header = swf_write_header,
514 .write_packet = swf_write_packet,
515 .write_trailer = swf_write_trailer,
516 .flags = AVFMT_TS_NONSTRICT,
519 #if CONFIG_AVM2_MUXER
520 AVOutputFormat ff_avm2_muxer = {
522 .long_name = NULL_IF_CONFIG_SMALL("Flash 9 (AVM2) format"),
523 .mime_type = "application/x-shockwave-flash",
524 .priv_data_size = sizeof(SWFContext),
525 .audio_codec = CODEC_ID_MP3,
526 .video_codec = CODEC_ID_FLV1,
527 .write_header = swf_write_header,
528 .write_packet = swf_write_packet,
529 .write_trailer = swf_write_trailer,
530 .flags = AVFMT_TS_NONSTRICT,