Statistics
| Branch: | Revision:

ffmpeg / libavformat / swfenc.c @ 72415b2a

History | View | Annotate | Download (15.6 KB)

1
/*
2
 * Flash Compatible Streaming Format muxer
3
 * Copyright (c) 2000 Fabrice Bellard
4
 * Copyright (c) 2003 Tinic Uro
5
 *
6
 * This file is part of FFmpeg.
7
 *
8
 * FFmpeg 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.
12
 *
13
 * FFmpeg 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.
17
 *
18
 * You should have received a copy of the GNU Lesser General Public
19
 * License along with FFmpeg; if not, write to the Free Software
20
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21
 */
22

    
23
#include "libavcodec/put_bits.h"
24
#include "avformat.h"
25
#include "swf.h"
26

    
27
static void put_swf_tag(AVFormatContext *s, int tag)
28
{
29
    SWFContext *swf = s->priv_data;
30
    ByteIOContext *pb = s->pb;
31

    
32
    swf->tag_pos = url_ftell(pb);
33
    swf->tag = tag;
34
    /* reserve some room for the tag */
35
    if (tag & TAG_LONG) {
36
        put_le16(pb, 0);
37
        put_le32(pb, 0);
38
    } else {
39
        put_le16(pb, 0);
40
    }
41
}
42

    
43
static void put_swf_end_tag(AVFormatContext *s)
44
{
45
    SWFContext *swf = s->priv_data;
46
    ByteIOContext *pb = s->pb;
47
    int64_t pos;
48
    int tag_len, tag;
49

    
50
    pos = url_ftell(pb);
51
    tag_len = pos - swf->tag_pos - 2;
52
    tag = swf->tag;
53
    url_fseek(pb, swf->tag_pos, SEEK_SET);
54
    if (tag & TAG_LONG) {
55
        tag &= ~TAG_LONG;
56
        put_le16(pb, (tag << 6) | 0x3f);
57
        put_le32(pb, tag_len - 4);
58
    } else {
59
        assert(tag_len < 0x3f);
60
        put_le16(pb, (tag << 6) | tag_len);
61
    }
62
    url_fseek(pb, pos, SEEK_SET);
63
}
64

    
65
static inline void max_nbits(int *nbits_ptr, int val)
66
{
67
    int n;
68

    
69
    if (val == 0)
70
        return;
71
    val = abs(val);
72
    n = 1;
73
    while (val != 0) {
74
        n++;
75
        val >>= 1;
76
    }
77
    if (n > *nbits_ptr)
78
        *nbits_ptr = n;
79
}
80

    
81
static void put_swf_rect(ByteIOContext *pb,
82
                         int xmin, int xmax, int ymin, int ymax)
83
{
84
    PutBitContext p;
85
    uint8_t buf[256];
86
    int nbits, mask;
87

    
88
    init_put_bits(&p, buf, sizeof(buf));
89

    
90
    nbits = 0;
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;
96

    
97
    /* rectangle info */
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);
103

    
104
    flush_put_bits(&p);
105
    put_buffer(pb, buf, put_bits_ptr(&p) - p.buf);
106
}
107

    
108
static void put_swf_line_edge(PutBitContext *pb, int dx, int dy)
109
{
110
    int nbits, mask;
111

    
112
    put_bits(pb, 1, 1); /* edge */
113
    put_bits(pb, 1, 1); /* line select */
114
    nbits = 2;
115
    max_nbits(&nbits, dx);
116
    max_nbits(&nbits, dy);
117

    
118
    mask = (1 << nbits) - 1;
119
    put_bits(pb, 4, nbits - 2); /* 16 bits precision */
120
    if (dx == 0) {
121
        put_bits(pb, 1, 0);
122
        put_bits(pb, 1, 1);
123
        put_bits(pb, nbits, dy & mask);
124
    } else if (dy == 0) {
125
        put_bits(pb, 1, 0);
126
        put_bits(pb, 1, 0);
127
        put_bits(pb, nbits, dx & mask);
128
    } else {
129
        put_bits(pb, 1, 1);
130
        put_bits(pb, nbits, dx & mask);
131
        put_bits(pb, nbits, dy & mask);
132
    }
133
}
134

    
135
#define FRAC_BITS 16
136

    
137
static void put_swf_matrix(ByteIOContext *pb,
138
                           int a, int b, int c, int d, int tx, int ty)
139
{
140
    PutBitContext p;
141
    uint8_t buf[256];
142
    int nbits;
143

    
144
    init_put_bits(&p, buf, sizeof(buf));
145

    
146
    put_bits(&p, 1, 1); /* a, d present */
147
    nbits = 1;
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);
153

    
154
    put_bits(&p, 1, 1); /* b, c present */
155
    nbits = 1;
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);
161

    
162
    nbits = 1;
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);
168

    
169
    flush_put_bits(&p);
170
    put_buffer(pb, buf, put_bits_ptr(&p) - p.buf);
171
}
172

    
173
static int swf_write_header(AVFormatContext *s)
174
{
175
    SWFContext *swf = s->priv_data;
176
    ByteIOContext *pb = s->pb;
177
    PutBitContext p;
178
    uint8_t buf1[256];
179
    int i, width, height, rate, rate_base;
180
    int version;
181

    
182
    swf->sound_samples = 0;
183
    swf->swf_frame_number = 0;
184
    swf->video_frame_number = 0;
185

    
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
                if (!enc->frame_size) {
191
                    av_log(s, AV_LOG_ERROR, "audio frame size not set\n");
192
                    return -1;
193
                }
194
                swf->audio_enc = enc;
195
                swf->audio_fifo= av_fifo_alloc(AUDIO_FIFO_SIZE);
196
                if (!swf->audio_fifo)
197
                    return AVERROR(ENOMEM);
198
            } else {
199
                av_log(s, AV_LOG_ERROR, "SWF muxer only supports MP3\n");
200
                return -1;
201
            }
202
        } else {
203
            if (enc->codec_id == CODEC_ID_VP6F ||
204
                enc->codec_id == CODEC_ID_FLV1 ||
205
                enc->codec_id == CODEC_ID_MJPEG) {
206
                swf->video_enc = enc;
207
            } else {
208
                av_log(s, AV_LOG_ERROR, "SWF muxer only supports VP6, FLV1 and MJPEG\n");
209
                return -1;
210
            }
211
        }
212
    }
213

    
214
    if (!swf->video_enc) {
215
        /* currently, cannot work correctly if audio only */
216
        width = 320;
217
        height = 200;
218
        rate = 10;
219
        rate_base= 1;
220
    } else {
221
        width = swf->video_enc->width;
222
        height = swf->video_enc->height;
223
        rate = swf->video_enc->time_base.den;
224
        rate_base = swf->video_enc->time_base.num;
225
    }
226

    
227
    if (!swf->audio_enc)
228
        swf->samples_per_frame = (44100. * rate_base) / rate;
229
    else
230
        swf->samples_per_frame = (swf->audio_enc->sample_rate * rate_base) / rate;
231

    
232
    put_tag(pb, "FWS");
233

    
234
    if (!strcmp("avm2", s->oformat->name))
235
        version = 9;
236
    else if (swf->video_enc && swf->video_enc->codec_id == CODEC_ID_VP6F)
237
        version = 8; /* version 8 and above support VP6 codec */
238
    else if (swf->video_enc && swf->video_enc->codec_id == CODEC_ID_FLV1)
239
        version = 6; /* version 6 and above support FLV1 codec */
240
    else
241
        version = 4; /* version 4 for mpeg audio support */
242
    put_byte(pb, version);
243

    
244
    put_le32(pb, DUMMY_FILE_SIZE); /* dummy size
245
                                      (will be patched if not streamed) */
246

    
247
    put_swf_rect(pb, 0, width * 20, 0, height * 20);
248
    put_le16(pb, (rate * 256) / rate_base); /* frame rate */
249
    swf->duration_pos = url_ftell(pb);
250
    put_le16(pb, (uint16_t)(DUMMY_DURATION * (int64_t)rate / rate_base)); /* frame count */
251

    
252
    /* avm2/swf v9 (also v8?) files require a file attribute tag */
253
    if (version == 9) {
254
        put_swf_tag(s, TAG_FILEATTRIBUTES);
255
        put_le32(pb, 1<<3); /* set ActionScript v3/AVM2 flag */
256
        put_swf_end_tag(s);
257
    }
258

    
259
    /* define a shape with the jpeg inside */
260
    if (swf->video_enc && swf->video_enc->codec_id == CODEC_ID_MJPEG) {
261
        put_swf_tag(s, TAG_DEFINESHAPE);
262

    
263
        put_le16(pb, SHAPE_ID); /* ID of shape */
264
        /* bounding rectangle */
265
        put_swf_rect(pb, 0, width, 0, height);
266
        /* style info */
267
        put_byte(pb, 1); /* one fill style */
268
        put_byte(pb, 0x41); /* clipped bitmap fill */
269
        put_le16(pb, BITMAP_ID); /* bitmap ID */
270
        /* position of the bitmap */
271
        put_swf_matrix(pb, (int)(1.0 * (1 << FRAC_BITS)), 0,
272
                       0, (int)(1.0 * (1 << FRAC_BITS)), 0, 0);
273
        put_byte(pb, 0); /* no line style */
274

    
275
        /* shape drawing */
276
        init_put_bits(&p, buf1, sizeof(buf1));
277
        put_bits(&p, 4, 1); /* one fill bit */
278
        put_bits(&p, 4, 0); /* zero line bit */
279

    
280
        put_bits(&p, 1, 0); /* not an edge */
281
        put_bits(&p, 5, FLAG_MOVETO | FLAG_SETFILL0);
282
        put_bits(&p, 5, 1); /* nbits */
283
        put_bits(&p, 1, 0); /* X */
284
        put_bits(&p, 1, 0); /* Y */
285
        put_bits(&p, 1, 1); /* set fill style 1 */
286

    
287
        /* draw the rectangle ! */
288
        put_swf_line_edge(&p, width, 0);
289
        put_swf_line_edge(&p, 0, height);
290
        put_swf_line_edge(&p, -width, 0);
291
        put_swf_line_edge(&p, 0, -height);
292

    
293
        /* end of shape */
294
        put_bits(&p, 1, 0); /* not an edge */
295
        put_bits(&p, 5, 0);
296

    
297
        flush_put_bits(&p);
298
        put_buffer(pb, buf1, put_bits_ptr(&p) - p.buf);
299

    
300
        put_swf_end_tag(s);
301
    }
302

    
303
    if (swf->audio_enc && swf->audio_enc->codec_id == CODEC_ID_MP3) {
304
        int v = 0;
305

    
306
        /* start sound */
307
        put_swf_tag(s, TAG_STREAMHEAD2);
308
        switch(swf->audio_enc->sample_rate) {
309
        case 11025: v |= 1 << 2; break;
310
        case 22050: v |= 2 << 2; break;
311
        case 44100: v |= 3 << 2; break;
312
        default:
313
            /* not supported */
314
            av_log(s, AV_LOG_ERROR, "swf does not support that sample rate, choose from (44100, 22050, 11025).\n");
315
            return -1;
316
        }
317
        v |= 0x02; /* 16 bit playback */
318
        if (swf->audio_enc->channels == 2)
319
            v |= 0x01; /* stereo playback */
320
        put_byte(s->pb, v);
321
        v |= 0x20; /* mp3 compressed */
322
        put_byte(s->pb, v);
323
        put_le16(s->pb, swf->samples_per_frame);  /* avg samples per frame */
324
        put_le16(s->pb, 0);
325

    
326
        put_swf_end_tag(s);
327
    }
328

    
329
    put_flush_packet(s->pb);
330
    return 0;
331
}
332

    
333
static int swf_write_video(AVFormatContext *s,
334
                           AVCodecContext *enc, const uint8_t *buf, int size)
335
{
336
    SWFContext *swf = s->priv_data;
337
    ByteIOContext *pb = s->pb;
338

    
339
    /* Flash Player limit */
340
    if (swf->swf_frame_number == 16000)
341
        av_log(enc, AV_LOG_INFO, "warning: Flash Player limit of 16000 frames reached\n");
342

    
343
    if (enc->codec_id == CODEC_ID_VP6F ||
344
        enc->codec_id == CODEC_ID_FLV1) {
345
        if (swf->video_frame_number == 0) {
346
            /* create a new video object */
347
            put_swf_tag(s, TAG_VIDEOSTREAM);
348
            put_le16(pb, VIDEO_ID);
349
            swf->vframes_pos = url_ftell(pb);
350
            put_le16(pb, 15000); /* hard flash player limit */
351
            put_le16(pb, enc->width);
352
            put_le16(pb, enc->height);
353
            put_byte(pb, 0);
354
            put_byte(pb,ff_codec_get_tag(swf_codec_tags,enc->codec_id));
355
            put_swf_end_tag(s);
356

    
357
            /* place the video object for the first time */
358
            put_swf_tag(s, TAG_PLACEOBJECT2);
359
            put_byte(pb, 0x36);
360
            put_le16(pb, 1);
361
            put_le16(pb, VIDEO_ID);
362
            put_swf_matrix(pb, 1 << FRAC_BITS, 0, 0, 1 << FRAC_BITS, 0, 0);
363
            put_le16(pb, swf->video_frame_number);
364
            put_tag(pb, "video");
365
            put_byte(pb, 0x00);
366
            put_swf_end_tag(s);
367
        } else {
368
            /* mark the character for update */
369
            put_swf_tag(s, TAG_PLACEOBJECT2);
370
            put_byte(pb, 0x11);
371
            put_le16(pb, 1);
372
            put_le16(pb, swf->video_frame_number);
373
            put_swf_end_tag(s);
374
        }
375

    
376
        /* set video frame data */
377
        put_swf_tag(s, TAG_VIDEOFRAME | TAG_LONG);
378
        put_le16(pb, VIDEO_ID);
379
        put_le16(pb, swf->video_frame_number++);
380
        put_buffer(pb, buf, size);
381
        put_swf_end_tag(s);
382
    } else if (enc->codec_id == CODEC_ID_MJPEG) {
383
        if (swf->swf_frame_number > 0) {
384
            /* remove the shape */
385
            put_swf_tag(s, TAG_REMOVEOBJECT);
386
            put_le16(pb, SHAPE_ID); /* shape ID */
387
            put_le16(pb, 1); /* depth */
388
            put_swf_end_tag(s);
389

    
390
            /* free the bitmap */
391
            put_swf_tag(s, TAG_FREECHARACTER);
392
            put_le16(pb, BITMAP_ID);
393
            put_swf_end_tag(s);
394
        }
395

    
396
        put_swf_tag(s, TAG_JPEG2 | TAG_LONG);
397

    
398
        put_le16(pb, BITMAP_ID); /* ID of the image */
399

    
400
        /* a dummy jpeg header seems to be required */
401
        put_be32(pb, 0xffd8ffd9);
402
        /* write the jpeg image */
403
        put_buffer(pb, buf, size);
404

    
405
        put_swf_end_tag(s);
406

    
407
        /* draw the shape */
408

    
409
        put_swf_tag(s, TAG_PLACEOBJECT);
410
        put_le16(pb, SHAPE_ID); /* shape ID */
411
        put_le16(pb, 1); /* depth */
412
        put_swf_matrix(pb, 20 << FRAC_BITS, 0, 0, 20 << FRAC_BITS, 0, 0);
413
        put_swf_end_tag(s);
414
    }
415

    
416
    swf->swf_frame_number++;
417

    
418
    /* streaming sound always should be placed just before showframe tags */
419
    if (swf->audio_enc && av_fifo_size(swf->audio_fifo)) {
420
        int frame_size = av_fifo_size(swf->audio_fifo);
421
        put_swf_tag(s, TAG_STREAMBLOCK | TAG_LONG);
422
        put_le16(pb, swf->sound_samples);
423
        put_le16(pb, 0); // seek samples
424
        av_fifo_generic_read(swf->audio_fifo, pb, frame_size, &put_buffer);
425
        put_swf_end_tag(s);
426

    
427
        /* update FIFO */
428
        swf->sound_samples = 0;
429
    }
430

    
431
    /* output the frame */
432
    put_swf_tag(s, TAG_SHOWFRAME);
433
    put_swf_end_tag(s);
434

    
435
    put_flush_packet(s->pb);
436

    
437
    return 0;
438
}
439

    
440
static int swf_write_audio(AVFormatContext *s,
441
                           AVCodecContext *enc, uint8_t *buf, int size)
442
{
443
    SWFContext *swf = s->priv_data;
444

    
445
    /* Flash Player limit */
446
    if (swf->swf_frame_number == 16000)
447
        av_log(enc, AV_LOG_INFO, "warning: Flash Player limit of 16000 frames reached\n");
448

    
449
    if (av_fifo_size(swf->audio_fifo) + size > AUDIO_FIFO_SIZE) {
450
        av_log(s, AV_LOG_ERROR, "audio fifo too small to mux audio essence\n");
451
        return -1;
452
    }
453

    
454
    av_fifo_generic_write(swf->audio_fifo, buf, size, NULL);
455
    swf->sound_samples += enc->frame_size;
456

    
457
    /* if audio only stream make sure we add swf frames */
458
    if (!swf->video_enc)
459
        swf_write_video(s, enc, 0, 0);
460

    
461
    return 0;
462
}
463

    
464
static int swf_write_packet(AVFormatContext *s, AVPacket *pkt)
465
{
466
    AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
467
    if (codec->codec_type == AVMEDIA_TYPE_AUDIO)
468
        return swf_write_audio(s, codec, pkt->data, pkt->size);
469
    else
470
        return swf_write_video(s, codec, pkt->data, pkt->size);
471
}
472

    
473
static int swf_write_trailer(AVFormatContext *s)
474
{
475
    SWFContext *swf = s->priv_data;
476
    ByteIOContext *pb = s->pb;
477
    AVCodecContext *enc, *video_enc;
478
    int file_size, i;
479

    
480
    video_enc = NULL;
481
    for(i=0;i<s->nb_streams;i++) {
482
        enc = s->streams[i]->codec;
483
        if (enc->codec_type == AVMEDIA_TYPE_VIDEO)
484
            video_enc = enc;
485
        else
486
            av_fifo_free(swf->audio_fifo);
487
    }
488

    
489
    put_swf_tag(s, TAG_END);
490
    put_swf_end_tag(s);
491

    
492
    put_flush_packet(s->pb);
493

    
494
    /* patch file size and number of frames if not streamed */
495
    if (!url_is_streamed(s->pb) && video_enc) {
496
        file_size = url_ftell(pb);
497
        url_fseek(pb, 4, SEEK_SET);
498
        put_le32(pb, file_size);
499
        url_fseek(pb, swf->duration_pos, SEEK_SET);
500
        put_le16(pb, swf->video_frame_number);
501
        url_fseek(pb, swf->vframes_pos, SEEK_SET);
502
        put_le16(pb, swf->video_frame_number);
503
        url_fseek(pb, file_size, SEEK_SET);
504
    }
505
    return 0;
506
}
507

    
508
#if CONFIG_SWF_MUXER
509
AVOutputFormat swf_muxer = {
510
    "swf",
511
    NULL_IF_CONFIG_SMALL("Flash format"),
512
    "application/x-shockwave-flash",
513
    "swf",
514
    sizeof(SWFContext),
515
    CODEC_ID_MP3,
516
    CODEC_ID_FLV1,
517
    swf_write_header,
518
    swf_write_packet,
519
    swf_write_trailer,
520
};
521
#endif
522
#if CONFIG_AVM2_MUXER
523
AVOutputFormat avm2_muxer = {
524
    "avm2",
525
    NULL_IF_CONFIG_SMALL("Flash 9 (AVM2) format"),
526
    "application/x-shockwave-flash",
527
    NULL,
528
    sizeof(SWFContext),
529
    CODEC_ID_MP3,
530
    CODEC_ID_FLV1,
531
    swf_write_header,
532
    swf_write_packet,
533
    swf_write_trailer,
534
};
535
#endif