libavformat/swfenc.c

   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 "config_components.h"
  24
  25 #include "libavcodec/put_bits.h"
  26 #include "libavutil/avassert.h"
  27 #include "libavutil/fifo.h"
  28 #include "avformat.h"
  29 #include "flv.h"
  30 #include "mux.h"
  31 #include "swf.h"
  32
  33 #define AUDIO_FIFO_SIZE 65536
  34
  35 typedef struct SWFEncContext {
  36     int64_t duration_pos;
  37     int64_t tag_pos;
  38     int64_t vframes_pos;
  39     int samples_per_frame;
  40     int sound_samples;
  41     int swf_frame_number;
  42     int video_frame_number;
  43     int tag;
  44     AVFifo *audio_fifo;
  45     AVCodecParameters *audio_par, *video_par;
  46     AVStream *video_st;
  47 } SWFEncContext;
  48
  49 static void put_swf_tag(AVFormatContext *s, int tag)
  50 {
  51     SWFEncContext *swf = s->priv_data;
  52     AVIOContext *pb = s->pb;
  53
  54     swf->tag_pos = avio_tell(pb);
  55     swf->tag = tag;
  56     /* reserve some room for the tag */
  57     if (tag & TAG_LONG) {
  58         avio_wl16(pb, 0);
  59         avio_wl32(pb, 0);
  60     } else {
  61         avio_wl16(pb, 0);
  62     }
  63 }
  64
  65 static void put_swf_end_tag(AVFormatContext *s)
  66 {
  67     SWFEncContext *swf = s->priv_data;
  68     AVIOContext *pb = s->pb;
  69     int64_t pos;
  70     int tag_len, tag;
  71
  72     pos = avio_tell(pb);
  73     tag_len = pos - swf->tag_pos - 2;
  74     tag = swf->tag;
  75     avio_seek(pb, swf->tag_pos, SEEK_SET);
  76     if (tag & TAG_LONG) {
  77         tag &= ~TAG_LONG;
  78         avio_wl16(pb, (tag << 6) | 0x3f);
  79         avio_wl32(pb, tag_len - 4);
  80     } else {
  81         av_assert0(tag_len < 0x3f);
  82         avio_wl16(pb, (tag << 6) | tag_len);
  83     }
  84     avio_seek(pb, pos, SEEK_SET);
  85 }
  86
  87 static inline void max_nbits(int *nbits_ptr, int val)
  88 {
  89     int n;
  90
  91     if (val == 0)
  92         return;
  93     val = FFABS(val);
  94     n = 1;
  95     while (val != 0) {
  96         n++;
  97         val >>= 1;
  98     }
  99     if (n > *nbits_ptr)
 100         *nbits_ptr = n;
 101 }
 102
 103 static void put_swf_rect(AVIOContext *pb,
 104                          int xmin, int xmax, int ymin, int ymax)
 105 {
 106     PutBitContext p;
 107     uint8_t buf[256];
 108     int nbits, mask;
 109
 110     init_put_bits(&p, buf, sizeof(buf));
 111
 112     nbits = 0;
 113     max_nbits(&nbits, xmin);
 114     max_nbits(&nbits, xmax);
 115     max_nbits(&nbits, ymin);
 116     max_nbits(&nbits, ymax);
 117     mask = (1 << nbits) - 1;
 118
 119     /* rectangle info */
 120     put_bits(&p, 5, nbits);
 121     put_bits(&p, nbits, xmin & mask);
 122     put_bits(&p, nbits, xmax & mask);
 123     put_bits(&p, nbits, ymin & mask);
 124     put_bits(&p, nbits, ymax & mask);
 125
 126     flush_put_bits(&p);
 127     avio_write(pb, buf, put_bits_ptr(&p) - p.buf);
 128 }
 129
 130 static void put_swf_line_edge(PutBitContext *pb, int dx, int dy)
 131 {
 132     int nbits, mask;
 133
 134     put_bits(pb, 1, 1); /* edge */
 135     put_bits(pb, 1, 1); /* line select */
 136     nbits = 2;
 137     max_nbits(&nbits, dx);
 138     max_nbits(&nbits, dy);
 139
 140     mask = (1 << nbits) - 1;
 141     put_bits(pb, 4, nbits - 2); /* 16 bits precision */
 142     if (dx == 0) {
 143         put_bits(pb, 1, 0);
 144         put_bits(pb, 1, 1);
 145         put_bits(pb, nbits, dy & mask);
 146     } else if (dy == 0) {
 147         put_bits(pb, 1, 0);
 148         put_bits(pb, 1, 0);
 149         put_bits(pb, nbits, dx & mask);
 150     } else {
 151         put_bits(pb, 1, 1);
 152         put_bits(pb, nbits, dx & mask);
 153         put_bits(pb, nbits, dy & mask);
 154     }
 155 }
 156
 157 #define FRAC_BITS 16
 158
 159 static void put_swf_matrix(AVIOContext *pb,
 160                            int a, int b, int c, int d, int tx, int ty)
 161 {
 162     PutBitContext p;
 163     uint8_t buf[256];
 164     int nbits;
 165
 166     init_put_bits(&p, buf, sizeof(buf));
 167
 168     put_bits(&p, 1, 1); /* a, d present */
 169     nbits = 1;
 170     max_nbits(&nbits, a);
 171     max_nbits(&nbits, d);
 172     put_bits(&p, 5, nbits); /* nb bits */
 173     put_bits(&p, nbits, a);
 174     put_bits(&p, nbits, d);
 175
 176     put_bits(&p, 1, 1); /* b, c present */
 177     nbits = 1;
 178     max_nbits(&nbits, c);
 179     max_nbits(&nbits, b);
 180     put_bits(&p, 5, nbits); /* nb bits */
 181     put_bits(&p, nbits, c);
 182     put_bits(&p, nbits, b);
 183
 184     nbits = 1;
 185     max_nbits(&nbits, tx);
 186     max_nbits(&nbits, ty);
 187     put_bits(&p, 5, nbits); /* nb bits */
 188     put_bits(&p, nbits, tx);
 189     put_bits(&p, nbits, ty);
 190
 191     flush_put_bits(&p);
 192     avio_write(pb, buf, put_bits_ptr(&p) - p.buf);
 193 }
 194
 195 static int swf_write_header(AVFormatContext *s)
 196 {
 197     SWFEncContext *swf = s->priv_data;
 198     AVIOContext *pb = s->pb;
 199     PutBitContext p;
 200     uint8_t buf1[256];
 201     int i, width, height, rate, rate_base;
 202     int version;
 203
 204     swf->sound_samples = 0;
 205     swf->swf_frame_number = 0;
 206     swf->video_frame_number = 0;
 207
 208     for(i=0;i<s->nb_streams;i++) {
 209         AVCodecParameters *par = s->streams[i]->codecpar;
 210         if (par->codec_type == AVMEDIA_TYPE_AUDIO) {
 211             if (par->codec_id == AV_CODEC_ID_MP3) {
 212                 swf->audio_par = par;
 213                 swf->audio_fifo = av_fifo_alloc2(AUDIO_FIFO_SIZE, 1, 0);
 214                 if (!swf->audio_fifo)
 215                     return AVERROR(ENOMEM);
 216             } else {
 217                 av_log(s, AV_LOG_ERROR, "SWF muxer only supports MP3\n");
 218                 return -1;
 219             }
 220         } else {
 221             if (ff_codec_get_tag(ff_swf_codec_tags, par->codec_id) ||
 222                 par->codec_id == AV_CODEC_ID_PNG ||
 223                 par->codec_id == AV_CODEC_ID_MJPEG) {
 224                 swf->video_st  = s->streams[i];
 225                 swf->video_par = par;
 226             } else {
 227                 av_log(s, AV_LOG_ERROR, "SWF muxer only supports VP6, FLV, Flash Screen Video, PNG and MJPEG\n");
 228                 return -1;
 229             }
 230         }
 231     }
 232
 233     if (!swf->video_par) {
 234         /* currently, cannot work correctly if audio only */
 235         width = 320;
 236         height = 200;
 237         rate = 10;
 238         rate_base= 1;
 239     } else {
 240         width = swf->video_par->width;
 241         height = swf->video_par->height;
 242         // TODO: should be avg_frame_rate
 243         rate = swf->video_st->time_base.den;
 244         rate_base = swf->video_st->time_base.num;
 245     }
 246
 247     if (!swf->audio_par)
 248         swf->samples_per_frame = (44100LL * rate_base) / rate;
 249     else
 250         swf->samples_per_frame = (swf->audio_par->sample_rate * rate_base) / rate;
 251
 252     avio_write(pb, "FWS", 3);
 253
 254     if (!strcmp("avm2", s->oformat->name))
 255         version = 9;
 256     else if (swf->video_par && (swf->video_par->codec_id == AV_CODEC_ID_VP6A ||
 257                                 swf->video_par->codec_id == AV_CODEC_ID_VP6F ||
 258                                 swf->video_par->codec_id == AV_CODEC_ID_PNG))
 259         version = 8; /* version 8 and above support VP6 and PNG codec */
 260     else if (swf->video_par && swf->video_par->codec_id == AV_CODEC_ID_FLASHSV)
 261         version = 7; /* version 7 and above support Flash Screen Video codec */
 262     else if (swf->video_par && swf->video_par->codec_id == AV_CODEC_ID_FLV1)
 263         version = 6; /* version 6 and above support FLV1 codec */
 264     else
 265         version = 4; /* version 4 for mpeg audio support */
 266     avio_w8(pb, version);
 267
 268     avio_wl32(pb, DUMMY_FILE_SIZE); /* dummy size
 269                                       (will be patched if not streamed) */
 270
 271     put_swf_rect(pb, 0, width * 20, 0, height * 20);
 272     if ((rate * 256LL) / rate_base >= (1<<16)) {
 273         av_log(s, AV_LOG_ERROR, "Invalid (too large) frame rate %d/%d\n", rate, rate_base);
 274         return AVERROR(EINVAL);
 275     }
 276     avio_wl16(pb, (rate * 256LL) / rate_base); /* frame rate */
 277     swf->duration_pos = avio_tell(pb);
 278     avio_wl16(pb, (uint16_t)(DUMMY_DURATION * (int64_t)rate / rate_base)); /* frame count */
 279
 280     /* swf v8 and later files require a file attribute tag */
 281     if (version >= 8) {
 282         put_swf_tag(s, TAG_FILEATTRIBUTES);
 283         avio_wl32(pb, (version >= 9) << 3); /* set ActionScript v3/AVM2 flag */
 284         put_swf_end_tag(s);
 285     }
 286
 287     /* define a shape with the jpeg inside */
 288     if (swf->video_par && (swf->video_par->codec_id == AV_CODEC_ID_MJPEG || swf->video_par->codec_id == AV_CODEC_ID_PNG)) {
 289         put_swf_tag(s, TAG_DEFINESHAPE);
 290
 291         avio_wl16(pb, SHAPE_ID); /* ID of shape */
 292         /* bounding rectangle */
 293         put_swf_rect(pb, 0, width, 0, height);
 294         /* style info */
 295         avio_w8(pb, 1); /* one fill style */
 296         avio_w8(pb, 0x41); /* clipped bitmap fill */
 297         avio_wl16(pb, BITMAP_ID); /* bitmap ID */
 298         /* position of the bitmap */
 299         put_swf_matrix(pb, 1 << FRAC_BITS, 0,
 300                        0,  1 << FRAC_BITS, 0, 0);
 301         avio_w8(pb, 0); /* no line style */
 302
 303         /* shape drawing */
 304         init_put_bits(&p, buf1, sizeof(buf1));
 305         put_bits(&p, 4, 1); /* one fill bit */
 306         put_bits(&p, 4, 0); /* zero line bit */
 307
 308         put_bits(&p, 1, 0); /* not an edge */
 309         put_bits(&p, 5, FLAG_MOVETO | FLAG_SETFILL0);
 310         put_bits(&p, 5, 1); /* nbits */
 311         put_bits(&p, 1, 0); /* X */
 312         put_bits(&p, 1, 0); /* Y */
 313         put_bits(&p, 1, 1); /* set fill style 1 */
 314
 315         /* draw the rectangle ! */
 316         put_swf_line_edge(&p, width, 0);
 317         put_swf_line_edge(&p, 0, height);
 318         put_swf_line_edge(&p, -width, 0);
 319         put_swf_line_edge(&p, 0, -height);
 320
 321         /* end of shape */
 322         put_bits(&p, 1, 0); /* not an edge */
 323         put_bits(&p, 5, 0);
 324
 325         flush_put_bits(&p);
 326         avio_write(pb, buf1, put_bits_ptr(&p) - p.buf);
 327
 328         put_swf_end_tag(s);
 329     }
 330
 331     if (swf->audio_par && swf->audio_par->codec_id == AV_CODEC_ID_MP3) {
 332         int v = 0;
 333
 334         /* start sound */
 335         put_swf_tag(s, TAG_STREAMHEAD2);
 336         switch(swf->audio_par->sample_rate) {
 337         case 11025: v |= 1 << 2; break;
 338         case 22050: v |= 2 << 2; break;
 339         case 44100: v |= 3 << 2; break;
 340         default:
 341             /* not supported */
 342             av_log(s, AV_LOG_ERROR, "swf does not support that sample rate, choose from (44100, 22050, 11025).\n");
 343             return -1;
 344         }
 345         v |= 0x02; /* 16 bit playback */
 346         if (swf->audio_par->ch_layout.nb_channels == 2)
 347             v |= 0x01; /* stereo playback */
 348         avio_w8(s->pb, v);
 349         v |= 0x20; /* mp3 compressed */
 350         avio_w8(s->pb, v);
 351         avio_wl16(s->pb, swf->samples_per_frame);  /* avg samples per frame */
 352         avio_wl16(s->pb, 0);
 353
 354         put_swf_end_tag(s);
 355     }
 356
 357     return 0;
 358 }
 359
 360 static int fifo_avio_wrapper(void *opaque, void *buf, size_t *nb_elems)
 361 {
 362     avio_write(opaque, buf, *nb_elems);
 363     return 0;
 364 }
 365
 366 static int swf_write_video(AVFormatContext *s,
 367                            AVCodecParameters *par, const uint8_t *buf, int size, unsigned pkt_flags)
 368 {
 369     SWFEncContext *swf = s->priv_data;
 370     AVIOContext *pb = s->pb;
 371     unsigned codec_tag = ff_codec_get_tag(ff_swf_codec_tags, par->codec_id);
 372
 373     /* Flash Player limit */
 374     if (swf->swf_frame_number == 16000)
 375         av_log(s, AV_LOG_INFO, "warning: Flash Player limit of 16000 frames reached\n");
 376
 377     if (codec_tag) {
 378         if (swf->video_frame_number == 0) {
 379             /* create a new video object */
 380             put_swf_tag(s, TAG_VIDEOSTREAM);
 381             avio_wl16(pb, VIDEO_ID);
 382             swf->vframes_pos = avio_tell(pb);
 383             avio_wl16(pb, 15000); /* hard flash player limit */
 384             avio_wl16(pb, par->width);
 385             avio_wl16(pb, par->height);
 386             avio_w8(pb, 0);
 387             avio_w8(pb, codec_tag);
 388             put_swf_end_tag(s);
 389
 390             /* place the video object for the first time */
 391             put_swf_tag(s, TAG_PLACEOBJECT2);
 392             avio_w8(pb, 0x36);
 393             avio_wl16(pb, 1);
 394             avio_wl16(pb, VIDEO_ID);
 395             put_swf_matrix(pb, 1 << FRAC_BITS, 0, 0, 1 << FRAC_BITS, 0, 0);
 396             avio_wl16(pb, swf->video_frame_number);
 397             avio_write(pb, "video", 5);
 398             avio_w8(pb, 0x00);
 399             put_swf_end_tag(s);
 400         } else {
 401             /* mark the character for update */
 402             put_swf_tag(s, TAG_PLACEOBJECT2);
 403             avio_w8(pb, 0x11);
 404             avio_wl16(pb, 1);
 405             avio_wl16(pb, swf->video_frame_number);
 406             put_swf_end_tag(s);
 407         }
 408
 409         /* set video frame data */
 410         put_swf_tag(s, TAG_VIDEOFRAME | TAG_LONG);
 411         avio_wl16(pb, VIDEO_ID);
 412         avio_wl16(pb, swf->video_frame_number++);
 413         if (par->codec_id == AV_CODEC_ID_FLASHSV) {
 414             /* FrameType and CodecId is needed here even if it is not documented correctly in the SWF specs */
 415             int flags = codec_tag | (pkt_flags & AV_PKT_FLAG_KEY ? FLV_FRAME_KEY : FLV_FRAME_INTER);
 416             avio_w8(pb, flags);
 417         }
 418         avio_write(pb, buf, size);
 419         put_swf_end_tag(s);
 420     } else if (par->codec_id == AV_CODEC_ID_MJPEG || par->codec_id == AV_CODEC_ID_PNG) {
 421         if (swf->swf_frame_number > 0) {
 422             /* remove the shape */
 423             put_swf_tag(s, TAG_REMOVEOBJECT);
 424             avio_wl16(pb, SHAPE_ID); /* shape ID */
 425             avio_wl16(pb, 1); /* depth */
 426             put_swf_end_tag(s);
 427
 428             /* free the bitmap */
 429             put_swf_tag(s, TAG_FREECHARACTER);
 430             avio_wl16(pb, BITMAP_ID);
 431             put_swf_end_tag(s);
 432         }
 433
 434         put_swf_tag(s, TAG_JPEG2 | TAG_LONG);
 435
 436         avio_wl16(pb, BITMAP_ID); /* ID of the image */
 437
 438         /* a dummy jpeg header seems to be required */
 439         if (par->codec_id == AV_CODEC_ID_MJPEG)
 440             avio_wb32(pb, 0xffd8ffd9);
 441         /* write the jpeg/png image */
 442         avio_write(pb, buf, size);
 443
 444         put_swf_end_tag(s);
 445
 446         /* draw the shape */
 447
 448         put_swf_tag(s, TAG_PLACEOBJECT);
 449         avio_wl16(pb, SHAPE_ID); /* shape ID */
 450         avio_wl16(pb, 1); /* depth */
 451         put_swf_matrix(pb, 20 << FRAC_BITS, 0, 0, 20 << FRAC_BITS, 0, 0);
 452         put_swf_end_tag(s);
 453     }
 454
 455     swf->swf_frame_number++;
 456
 457     /* streaming sound always should be placed just before showframe tags */
 458     if (swf->audio_par && av_fifo_can_read(swf->audio_fifo)) {
 459         size_t frame_size = av_fifo_can_read(swf->audio_fifo);
 460         put_swf_tag(s, TAG_STREAMBLOCK | TAG_LONG);
 461         avio_wl16(pb, swf->sound_samples);
 462         avio_wl16(pb, 0); // seek samples
 463         av_fifo_read_to_cb(swf->audio_fifo, fifo_avio_wrapper, pb, &frame_size);
 464         put_swf_end_tag(s);
 465
 466         /* update FIFO */
 467         swf->sound_samples = 0;
 468     }
 469
 470     /* output the frame */
 471     put_swf_tag(s, TAG_SHOWFRAME);
 472     put_swf_end_tag(s);
 473
 474     return 0;
 475 }
 476
 477 static int swf_write_audio(AVFormatContext *s, AVCodecParameters *par,
 478                            const uint8_t *buf, int size)
 479 {
 480     SWFEncContext *swf = s->priv_data;
 481
 482     /* Flash Player limit */
 483     if (swf->swf_frame_number == 16000)
 484         av_log(s, AV_LOG_INFO, "warning: Flash Player limit of 16000 frames reached\n");
 485
 486     if (av_fifo_can_write(swf->audio_fifo) < size) {
 487         av_log(s, AV_LOG_ERROR, "audio fifo too small to mux audio essence\n");
 488         return -1;
 489     }
 490
 491     av_fifo_write(swf->audio_fifo, buf, size);
 492     swf->sound_samples += av_get_audio_frame_duration2(par, size);
 493
 494     /* if audio only stream make sure we add swf frames */
 495     if (!swf->video_par)
 496         swf_write_video(s, par, 0, 0, 0);
 497
 498     return 0;
 499 }
 500
 501 static int swf_write_packet(AVFormatContext *s, AVPacket *pkt)
 502 {
 503     AVCodecParameters *par = s->streams[pkt->stream_index]->codecpar;
 504     if (par->codec_type == AVMEDIA_TYPE_AUDIO)
 505         return swf_write_audio(s, par, pkt->data, pkt->size);
 506     else
 507         return swf_write_video(s, par, pkt->data, pkt->size, pkt->flags);
 508 }
 509
 510 static int swf_write_trailer(AVFormatContext *s)
 511 {
 512     SWFEncContext *swf = s->priv_data;
 513     AVIOContext *pb = s->pb;
 514     int file_size;
 515
 516     put_swf_tag(s, TAG_END);
 517     put_swf_end_tag(s);
 518
 519     /* patch file size and number of frames if not streamed */
 520     if ((s->pb->seekable & AVIO_SEEKABLE_NORMAL) && swf->video_par) {
 521         file_size = avio_tell(pb);
 522         avio_seek(pb, 4, SEEK_SET);
 523         avio_wl32(pb, file_size);
 524         avio_seek(pb, swf->duration_pos, SEEK_SET);
 525         avio_wl16(pb, swf->video_frame_number);
 526         if (swf->vframes_pos) {
 527         avio_seek(pb, swf->vframes_pos, SEEK_SET);
 528         avio_wl16(pb, swf->video_frame_number);
 529         }
 530         avio_seek(pb, file_size, SEEK_SET);
 531     }
 532     return 0;
 533 }
 534
 535 static void swf_deinit(AVFormatContext *s)
 536 {
 537     SWFEncContext *swf = s->priv_data;
 538
 539     av_fifo_freep2(&swf->audio_fifo);
 540 }
 541
 542 #if CONFIG_SWF_MUXER
 543 const FFOutputFormat ff_swf_muxer = {
 544     .p.name            = "swf",
 545     .p.long_name       = NULL_IF_CONFIG_SMALL("SWF (ShockWave Flash)"),
 546     .p.mime_type       = "application/x-shockwave-flash",
 547     .p.extensions      = "swf",
 548     .priv_data_size    = sizeof(SWFEncContext),
 549     .p.audio_codec     = AV_CODEC_ID_MP3,
 550     .p.video_codec     = AV_CODEC_ID_FLV1,
 551     .p.subtitle_codec  = AV_CODEC_ID_NONE,
 552     .write_header      = swf_write_header,
 553     .write_packet      = swf_write_packet,
 554     .write_trailer     = swf_write_trailer,
 555     .deinit            = swf_deinit,
 556     .p.flags           = AVFMT_TS_NONSTRICT,
 557     .flags_internal    = FF_OFMT_FLAG_MAX_ONE_OF_EACH,
 558 };
 559 #endif
 560 #if CONFIG_AVM2_MUXER
 561 const FFOutputFormat ff_avm2_muxer = {
 562     .p.name            = "avm2",
 563     .p.long_name       = NULL_IF_CONFIG_SMALL("SWF (ShockWave Flash) (AVM2)"),
 564     .p.mime_type       = "application/x-shockwave-flash",
 565     .priv_data_size    = sizeof(SWFEncContext),
 566     .p.audio_codec     = AV_CODEC_ID_MP3,
 567     .p.video_codec     = AV_CODEC_ID_FLV1,
 568     .p.subtitle_codec  = AV_CODEC_ID_NONE,
 569     .write_header      = swf_write_header,
 570     .write_packet      = swf_write_packet,
 571     .write_trailer     = swf_write_trailer,
 572     .deinit            = swf_deinit,
 573     .p.flags           = AVFMT_TS_NONSTRICT,
 574     .flags_internal    = FF_OFMT_FLAG_MAX_ONE_OF_EACH,
 575 };
 576 #endif