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 (swf->audio_enc) {
190 av_log(s, AV_LOG_ERROR, "SWF muxer only supports 1 audio stream\n");
191 return AVERROR_INVALIDDATA;
193 if (enc->codec_id == AV_CODEC_ID_MP3) {
194 swf->audio_enc = enc;
195 swf->audio_fifo= av_fifo_alloc(AUDIO_FIFO_SIZE);
196 if (!swf->audio_fifo)
197 return AVERROR(ENOMEM);
199 av_log(s, AV_LOG_ERROR, "SWF muxer only supports MP3\n");
203 if (swf->video_enc) {
204 av_log(s, AV_LOG_ERROR, "SWF muxer only supports 1 video stream\n");
205 return AVERROR_INVALIDDATA;
207 if (enc->codec_id == AV_CODEC_ID_VP6F ||
208 enc->codec_id == AV_CODEC_ID_FLV1 ||
209 enc->codec_id == AV_CODEC_ID_MJPEG) {
210 swf->video_st = s->streams[i];
211 swf->video_enc = enc;
213 av_log(s, AV_LOG_ERROR, "SWF muxer only supports VP6, FLV1 and MJPEG\n");
219 if (!swf->video_enc) {
220 /* currently, cannot work correctly if audio only */
226 width = swf->video_enc->width;
227 height = swf->video_enc->height;
228 // TODO: should be avg_frame_rate
229 rate = swf->video_st->time_base.den;
230 rate_base = swf->video_st->time_base.num;
234 swf->samples_per_frame = (44100.0 * rate_base) / rate;
236 swf->samples_per_frame = (swf->audio_enc->sample_rate * rate_base) / rate;
238 avio_write(pb, "FWS", 3);
240 if (!strcmp("avm2", s->oformat->name))
242 else if (swf->video_enc && swf->video_enc->codec_id == AV_CODEC_ID_VP6F)
243 version = 8; /* version 8 and above support VP6 codec */
244 else if (swf->video_enc && swf->video_enc->codec_id == AV_CODEC_ID_FLV1)
245 version = 6; /* version 6 and above support FLV1 codec */
247 version = 4; /* version 4 for mpeg audio support */
248 avio_w8(pb, version);
250 avio_wl32(pb, DUMMY_FILE_SIZE); /* dummy size
251 (will be patched if not streamed) */
253 put_swf_rect(pb, 0, width * 20, 0, height * 20);
254 avio_wl16(pb, (rate * 256) / rate_base); /* frame rate */
255 swf->duration_pos = avio_tell(pb);
256 avio_wl16(pb, (uint16_t)(DUMMY_DURATION * (int64_t)rate / rate_base)); /* frame count */
258 /* avm2/swf v9 (also v8?) files require a file attribute tag */
260 put_swf_tag(s, TAG_FILEATTRIBUTES);
261 avio_wl32(pb, 1<<3); /* set ActionScript v3/AVM2 flag */
265 /* define a shape with the jpeg inside */
266 if (swf->video_enc && swf->video_enc->codec_id == AV_CODEC_ID_MJPEG) {
267 put_swf_tag(s, TAG_DEFINESHAPE);
269 avio_wl16(pb, SHAPE_ID); /* ID of shape */
270 /* bounding rectangle */
271 put_swf_rect(pb, 0, width, 0, height);
273 avio_w8(pb, 1); /* one fill style */
274 avio_w8(pb, 0x41); /* clipped bitmap fill */
275 avio_wl16(pb, BITMAP_ID); /* bitmap ID */
276 /* position of the bitmap */
277 put_swf_matrix(pb, (int)(1.0 * (1 << FRAC_BITS)), 0,
278 0, (int)(1.0 * (1 << FRAC_BITS)), 0, 0);
279 avio_w8(pb, 0); /* no line style */
282 init_put_bits(&p, buf1, sizeof(buf1));
283 put_bits(&p, 4, 1); /* one fill bit */
284 put_bits(&p, 4, 0); /* zero line bit */
286 put_bits(&p, 1, 0); /* not an edge */
287 put_bits(&p, 5, FLAG_MOVETO | FLAG_SETFILL0);
288 put_bits(&p, 5, 1); /* nbits */
289 put_bits(&p, 1, 0); /* X */
290 put_bits(&p, 1, 0); /* Y */
291 put_bits(&p, 1, 1); /* set fill style 1 */
293 /* draw the rectangle ! */
294 put_swf_line_edge(&p, width, 0);
295 put_swf_line_edge(&p, 0, height);
296 put_swf_line_edge(&p, -width, 0);
297 put_swf_line_edge(&p, 0, -height);
300 put_bits(&p, 1, 0); /* not an edge */
304 avio_write(pb, buf1, put_bits_ptr(&p) - p.buf);
309 if (swf->audio_enc && swf->audio_enc->codec_id == AV_CODEC_ID_MP3) {
313 put_swf_tag(s, TAG_STREAMHEAD2);
314 switch(swf->audio_enc->sample_rate) {
315 case 11025: v |= 1 << 2; break;
316 case 22050: v |= 2 << 2; break;
317 case 44100: v |= 3 << 2; break;
320 av_log(s, AV_LOG_ERROR, "swf does not support that sample rate, choose from (44100, 22050, 11025).\n");
323 v |= 0x02; /* 16 bit playback */
324 if (swf->audio_enc->channels == 2)
325 v |= 0x01; /* stereo playback */
327 v |= 0x20; /* mp3 compressed */
329 avio_wl16(s->pb, swf->samples_per_frame); /* avg samples per frame */
339 static int swf_write_video(AVFormatContext *s,
340 AVCodecContext *enc, const uint8_t *buf, int size)
342 SWFContext *swf = s->priv_data;
343 AVIOContext *pb = s->pb;
345 /* Flash Player limit */
346 if (swf->swf_frame_number == 16000)
347 av_log(enc, AV_LOG_INFO, "warning: Flash Player limit of 16000 frames reached\n");
349 if (enc->codec_id == AV_CODEC_ID_VP6F ||
350 enc->codec_id == AV_CODEC_ID_FLV1) {
351 if (swf->video_frame_number == 0) {
352 /* create a new video object */
353 put_swf_tag(s, TAG_VIDEOSTREAM);
354 avio_wl16(pb, VIDEO_ID);
355 swf->vframes_pos = avio_tell(pb);
356 avio_wl16(pb, 15000); /* hard flash player limit */
357 avio_wl16(pb, enc->width);
358 avio_wl16(pb, enc->height);
360 avio_w8(pb,ff_codec_get_tag(ff_swf_codec_tags, enc->codec_id));
363 /* place the video object for the first time */
364 put_swf_tag(s, TAG_PLACEOBJECT2);
367 avio_wl16(pb, VIDEO_ID);
368 put_swf_matrix(pb, 1 << FRAC_BITS, 0, 0, 1 << FRAC_BITS, 0, 0);
369 avio_wl16(pb, swf->video_frame_number);
370 avio_write(pb, "video", 5);
374 /* mark the character for update */
375 put_swf_tag(s, TAG_PLACEOBJECT2);
378 avio_wl16(pb, swf->video_frame_number);
382 /* set video frame data */
383 put_swf_tag(s, TAG_VIDEOFRAME | TAG_LONG);
384 avio_wl16(pb, VIDEO_ID);
385 avio_wl16(pb, swf->video_frame_number++);
386 avio_write(pb, buf, size);
388 } else if (enc->codec_id == AV_CODEC_ID_MJPEG) {
389 if (swf->swf_frame_number > 0) {
390 /* remove the shape */
391 put_swf_tag(s, TAG_REMOVEOBJECT);
392 avio_wl16(pb, SHAPE_ID); /* shape ID */
393 avio_wl16(pb, 1); /* depth */
396 /* free the bitmap */
397 put_swf_tag(s, TAG_FREECHARACTER);
398 avio_wl16(pb, BITMAP_ID);
402 put_swf_tag(s, TAG_JPEG2 | TAG_LONG);
404 avio_wl16(pb, BITMAP_ID); /* ID of the image */
406 /* a dummy jpeg header seems to be required */
407 avio_wb32(pb, 0xffd8ffd9);
408 /* write the jpeg image */
409 avio_write(pb, buf, size);
415 put_swf_tag(s, TAG_PLACEOBJECT);
416 avio_wl16(pb, SHAPE_ID); /* shape ID */
417 avio_wl16(pb, 1); /* depth */
418 put_swf_matrix(pb, 20 << FRAC_BITS, 0, 0, 20 << FRAC_BITS, 0, 0);
422 swf->swf_frame_number++;
424 /* streaming sound always should be placed just before showframe tags */
425 if (swf->audio_enc && av_fifo_size(swf->audio_fifo)) {
426 int frame_size = av_fifo_size(swf->audio_fifo);
427 put_swf_tag(s, TAG_STREAMBLOCK | TAG_LONG);
428 avio_wl16(pb, swf->sound_samples);
429 avio_wl16(pb, 0); // seek samples
430 av_fifo_generic_read(swf->audio_fifo, pb, frame_size, &avio_write);
434 swf->sound_samples = 0;
437 /* output the frame */
438 put_swf_tag(s, TAG_SHOWFRAME);
444 static int swf_write_audio(AVFormatContext *s,
445 AVCodecContext *enc, uint8_t *buf, int size)
447 SWFContext *swf = s->priv_data;
449 /* Flash Player limit */
450 if (swf->swf_frame_number == 16000)
451 av_log(enc, AV_LOG_INFO, "warning: Flash Player limit of 16000 frames reached\n");
453 if (av_fifo_size(swf->audio_fifo) + size > AUDIO_FIFO_SIZE) {
454 av_log(s, AV_LOG_ERROR, "audio fifo too small to mux audio essence\n");
458 av_fifo_generic_write(swf->audio_fifo, buf, size, NULL);
459 swf->sound_samples += av_get_audio_frame_duration(enc, size);
461 /* if audio only stream make sure we add swf frames */
463 swf_write_video(s, enc, 0, 0);
468 static int swf_write_packet(AVFormatContext *s, AVPacket *pkt)
470 AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
471 if (codec->codec_type == AVMEDIA_TYPE_AUDIO)
472 return swf_write_audio(s, codec, pkt->data, pkt->size);
474 return swf_write_video(s, codec, pkt->data, pkt->size);
477 static int swf_write_trailer(AVFormatContext *s)
479 SWFContext *swf = s->priv_data;
480 AVIOContext *pb = s->pb;
481 AVCodecContext *enc, *video_enc;
485 for(i=0;i<s->nb_streams;i++) {
486 enc = s->streams[i]->codec;
487 if (enc->codec_type == AVMEDIA_TYPE_VIDEO)
490 av_fifo_free(swf->audio_fifo);
493 put_swf_tag(s, TAG_END);
496 /* patch file size and number of frames if not streamed */
497 if (s->pb->seekable && video_enc) {
498 file_size = avio_tell(pb);
499 avio_seek(pb, 4, SEEK_SET);
500 avio_wl32(pb, file_size);
501 avio_seek(pb, swf->duration_pos, SEEK_SET);
502 avio_wl16(pb, swf->video_frame_number);
503 avio_seek(pb, swf->vframes_pos, SEEK_SET);
504 avio_wl16(pb, swf->video_frame_number);
505 avio_seek(pb, file_size, SEEK_SET);
511 AVOutputFormat ff_swf_muxer = {
513 .long_name = NULL_IF_CONFIG_SMALL("SWF (ShockWave Flash)"),
514 .mime_type = "application/x-shockwave-flash",
516 .priv_data_size = sizeof(SWFContext),
517 .audio_codec = AV_CODEC_ID_MP3,
518 .video_codec = AV_CODEC_ID_FLV1,
519 .write_header = swf_write_header,
520 .write_packet = swf_write_packet,
521 .write_trailer = swf_write_trailer,
522 .flags = AVFMT_TS_NONSTRICT,
525 #if CONFIG_AVM2_MUXER
526 AVOutputFormat ff_avm2_muxer = {
528 .long_name = NULL_IF_CONFIG_SMALL("SWF (ShockWave Flash) (AVM2)"),
529 .mime_type = "application/x-shockwave-flash",
530 .priv_data_size = sizeof(SWFContext),
531 .audio_codec = AV_CODEC_ID_MP3,
532 .video_codec = AV_CODEC_ID_FLV1,
533 .write_header = swf_write_header,
534 .write_packet = swf_write_packet,
535 .write_trailer = swf_write_trailer,
536 .flags = AVFMT_TS_NONSTRICT,