git.sesse.net Git - mlt/blob - src/modules/avformat/producer_avformat.c

   1 /*
   2  * producer_avformat.c -- avformat producer
   3  * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
   4  * Author: Charles Yates <charles.yates@pandora.be>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 // Local header files
  22 #include "producer_avformat.h"
  23
  24 // MLT Header files
  25 #include <framework/mlt_frame.h>
  26
  27 // ffmpeg Header files
  28 #include <ffmpeg/avformat.h>
  29
  30 // System header files
  31 #include <stdlib.h>
  32 #include <string.h>
  33 #include <pthread.h>
  34 #include <math.h>
  35
  36 // Forward references.
  37 static int producer_open( mlt_producer this, char *file );
  38 static int producer_get_frame( mlt_producer this, mlt_frame_ptr frame, int index );
  39
  40 // A static flag used to determine if avformat has been initialised
  41 static int avformat_initialised = 0;
  42 static pthread_mutex_t avformat_mutex;
  43
  44 #if 0
  45 void *av_malloc( unsigned int size )
  46 {
  47         return mlt_pool_alloc( size );
  48 }
  49
  50 void *av_realloc( void *ptr, unsigned int size )
  51 {
  52         return mlt_pool_realloc( ptr, size );
  53 }
  54
  55 void av_free( void *ptr )
  56 {
  57         return mlt_pool_release( ptr );
  58 }
  59 #endif
  60
  61 /** Constructor for libavformat.
  62 */
  63
  64 mlt_producer producer_avformat_init( char *file )
  65 {
  66         mlt_producer this = NULL;
  67
  68         // Check that we have a non-NULL argument
  69         if ( file != NULL )
  70         {
  71                 // Construct the producer
  72                 this = calloc( 1, sizeof( struct mlt_producer_s ) );
  73
  74                 // Initialise it
  75                 if ( mlt_producer_init( this, NULL ) == 0 )
  76                 {
  77                         // Get the properties
  78                         mlt_properties properties = mlt_producer_properties( this );
  79
  80                         // Set the resource property (required for all producers)
  81                         mlt_properties_set( properties, "resource", file );
  82
  83                         // TEST: audio sync tweaking
  84                         mlt_properties_set_double( properties, "discrepancy", 1 );
  85
  86                         // Register our get_frame implementation
  87                         this->get_frame = producer_get_frame;
  88
  89                         // Initialise avformat if necessary
  90                         if ( avformat_initialised == 0 )
  91                         {
  92                                 avformat_initialised = 1;
  93                                 pthread_mutex_init( &avformat_mutex, NULL );
  94                                 av_register_all( );
  95                         }
  96
  97                         // Open the file
  98                         if ( producer_open( this, file ) != 0 )
  99                         {
 100                                 // Clean up
 101                                 mlt_producer_close( this );
 102                                 this = NULL;
 103                         }
 104                 }
 105         }
 106
 107         return this;
 108 }
 109
 110 /** Find the default streams.
 111 */
 112
 113 static void find_default_streams( AVFormatContext *context, int *audio_index, int *video_index )
 114 {
 115         int i;
 116
 117         // Allow for multiple audio and video streams in the file and select first of each (if available)
 118         for( i = 0; i < context->nb_streams; i++ )
 119         {
 120                 // Get the codec context
 121                 AVCodecContext *codec_context = &context->streams[ i ]->codec;
 122
 123                 // Determine the type and obtain the first index of each type
 124                 switch( codec_context->codec_type )
 125                 {
 126                         case CODEC_TYPE_VIDEO:
 127                                 if ( *video_index < 0 )
 128                                         *video_index = i;
 129                                 break;
 130                         case CODEC_TYPE_AUDIO:
 131                                 if ( *audio_index < 0 )
 132                                         *audio_index = i;
 133                                 break;
 134                         default:
 135                                 break;
 136                 }
 137         }
 138 }
 139
 140 /** Producer file destructor.
 141 */
 142
 143 static void producer_file_close( void *context )
 144 {
 145         if ( context != NULL )
 146         {
 147                 // Lock the mutex now
 148                 pthread_mutex_lock( &avformat_mutex );
 149
 150                 // Close the file
 151                 av_close_input_file( context );
 152
 153                 // Unlock the mutex now
 154                 pthread_mutex_unlock( &avformat_mutex );
 155         }
 156 }
 157
 158 /** Producer file destructor.
 159 */
 160
 161 static void producer_codec_close( void *codec )
 162 {
 163         if ( codec != NULL )
 164         {
 165                 // Lock the mutex now
 166                 pthread_mutex_lock( &avformat_mutex );
 167
 168                 // Close the file
 169                 avcodec_close( codec );
 170
 171                 // Unlock the mutex now
 172                 pthread_mutex_unlock( &avformat_mutex );
 173         }
 174 }
 175
 176 /** Open the file.
 177 */
 178
 179 static int producer_open( mlt_producer this, char *file )
 180 {
 181         // Return an error code (0 == no error)
 182         int error = 0;
 183
 184         // Context for avformat
 185         AVFormatContext *context = NULL;
 186
 187         // Get the properties
 188         mlt_properties properties = mlt_producer_properties( this );
 189
 190         // We will treat everything with the producer fps
 191         double fps = mlt_properties_get_double( properties, "fps" );
 192
 193         // Lock the mutex now
 194         pthread_mutex_lock( &avformat_mutex );
 195
 196         // If "MRL", then create AVInputFormat
 197         AVInputFormat *format = NULL;
 198         AVFormatParameters *params = NULL;
 199         char *standard = NULL;
 200         char *mrl = strchr( file, ':' );
 201
 202         // Only if there is not a protocol specification that avformat can handle
 203         if ( mrl && !url_exist( file ) )
 204         {
 205                 // 'file' becomes format abbreviation
 206                 mrl[0] = 0;
 207
 208                 // Lookup the format
 209                 format = av_find_input_format( file );
 210
 211                 // Eat the format designator
 212                 file = ++mrl;
 213
 214                 if ( format )
 215                 {
 216                         // Allocate params
 217                         params = calloc( sizeof( AVFormatParameters ), 1 );
 218
 219                         // These are required by video4linux (defaults)
 220                         params->width = 640;
 221                         params->height = 480;
 222                         params->frame_rate = 25;
 223                         params->frame_rate_base = 1;
 224                         params->device = file;
 225                         params->channels = 2;
 226                         params->sample_rate = 48000;
 227                 }
 228
 229                 // Parse out params
 230                 mrl = strchr( file, '?' );
 231                 while ( mrl )
 232                 {
 233                         mrl[0] = 0;
 234                         char *name = strdup( ++mrl );
 235                         char *value = strchr( name, ':' );
 236                         if ( value )
 237                         {
 238                                 value[0] = 0;
 239                                 value++;
 240                                 char *t = strchr( value, '&' );
 241                                 if ( t )
 242                                         t[0] = 0;
 243                                 if ( !strcmp( name, "frame_rate" ) )
 244                                         params->frame_rate = atoi( value );
 245                                 else if ( !strcmp( name, "frame_rate_base" ) )
 246                                         params->frame_rate_base = atoi( value );
 247                                 else if ( !strcmp( name, "sample_rate" ) )
 248                                         params->sample_rate = atoi( value );
 249                                 else if ( !strcmp( name, "channels" ) )
 250                                         params->channels = atoi( value );
 251                                 else if ( !strcmp( name, "width" ) )
 252                                         params->width = atoi( value );
 253                                 else if ( !strcmp( name, "height" ) )
 254                                         params->height = atoi( value );
 255                                 else if ( !strcmp( name, "standard" ) )
 256                                 {
 257                                         standard = strdup( value );
 258                                         params->standard = standard;
 259                                 }
 260                         }
 261                         free( name );
 262                         mrl = strchr( mrl, '&' );
 263                 }
 264         }
 265
 266         // Now attempt to open the file
 267         error = av_open_input_file( &context, file, format, 0, params );
 268         error = error < 0;
 269
 270         // Cleanup AVFormatParameters
 271         free( standard );
 272         free( params );
 273
 274         // If successful, then try to get additional info
 275         if ( error == 0 )
 276         {
 277                 // Get the stream info
 278                 error = av_find_stream_info( context ) < 0;
 279
 280                 // Continue if no error
 281                 if ( error == 0 )
 282                 {
 283                         // We will default to the first audio and video streams found
 284                         int audio_index = -1;
 285                         int video_index = -1;
 286
 287                         // Now set properties where we can (use default unknowns if required)
 288                         if ( context->duration != AV_NOPTS_VALUE )
 289                         {
 290                                 // This isn't going to be accurate for all formats
 291                                 mlt_position frames = ( mlt_position )( ( ( double )context->duration / ( double )AV_TIME_BASE ) * fps );
 292                                 mlt_properties_set_position( properties, "out", frames - 2 );
 293                                 mlt_properties_set_position( properties, "length", frames - 1 );
 294                         }
 295
 296                         // Find default audio and video streams
 297                         find_default_streams( context, &audio_index, &video_index );
 298
 299                         // Store selected audio and video indexes on properties
 300                         mlt_properties_set_int( properties, "audio_index", audio_index );
 301                         mlt_properties_set_int( properties, "video_index", video_index );
 302
 303                         // We're going to cheat here - for a/v files, we will have two contexts (reasoning will be clear later)
 304                         if ( audio_index != -1 && video_index != -1 )
 305                         {
 306                                 // We'll use the open one as our video_context
 307                                 mlt_properties_set_data( properties, "video_context", context, 0, producer_file_close, NULL );
 308
 309                                 // And open again for our audio context
 310                                 av_open_input_file( &context, file, NULL, 0, NULL );
 311                                 av_find_stream_info( context );
 312
 313                                 // Audio context
 314                                 mlt_properties_set_data( properties, "audio_context", context, 0, producer_file_close, NULL );
 315                         }
 316                         else if ( video_index != -1 )
 317                         {
 318                                 // We only have a video context
 319                                 mlt_properties_set_data( properties, "video_context", context, 0, producer_file_close, NULL );
 320                         }
 321                         else if ( audio_index != -1 )
 322                         {
 323                                 // We only have an audio context
 324                                 mlt_properties_set_data( properties, "audio_context", context, 0, producer_file_close, NULL );
 325                         }
 326                         else
 327                         {
 328                                 // Something has gone wrong
 329                                 error = -1;
 330                         }
 331                 }
 332         }
 333
 334         // Unlock the mutex now
 335         pthread_mutex_unlock( &avformat_mutex );
 336
 337         return error;
 338 }
 339
 340 /** Convert a frame position to a time code.
 341 */
 342
 343 static double producer_time_of_frame( mlt_producer this, mlt_position position )
 344 {
 345         // Get the properties
 346         mlt_properties properties = mlt_producer_properties( this );
 347
 348         // Obtain the fps
 349         double fps = mlt_properties_get_double( properties, "fps" );
 350
 351         // Do the calc
 352         return ( double )position / fps;
 353 }
 354
 355 /** Get an image from a frame.
 356 */
 357
 358 static int producer_get_image( mlt_frame frame, uint8_t **buffer, mlt_image_format *format, int *width, int *height, int writable )
 359 {
 360         // Get the properties from the frame
 361         mlt_properties frame_properties = mlt_frame_properties( frame );
 362
 363         // Obtain the frame number of this frame
 364         mlt_position position = mlt_properties_get_position( frame_properties, "avformat_position" );
 365
 366         // Get the producer
 367         mlt_producer this = mlt_properties_get_data( frame_properties, "avformat_producer", NULL );
 368
 369         // Get the producer properties
 370         mlt_properties properties = mlt_producer_properties( this );
 371
 372         // Fetch the video_context
 373         AVFormatContext *context = mlt_properties_get_data( properties, "video_context", NULL );
 374
 375         // Get the video_index
 376         int index = mlt_properties_get_int( properties, "video_index" );
 377
 378         // Obtain the expected frame numer
 379         mlt_position expected = mlt_properties_get_position( properties, "video_expected" );
 380
 381         // Calculate the real time code
 382         double real_timecode = producer_time_of_frame( this, position );
 383
 384         // Get the video stream
 385         AVStream *stream = context->streams[ index ];
 386
 387         // Get codec context
 388         AVCodecContext *codec_context = &stream->codec;
 389
 390         // Packet
 391         AVPacket pkt;
 392
 393         // Get the conversion frame
 394         AVPicture *output = mlt_properties_get_data( properties, "video_output_frame", NULL );
 395
 396         // Special case pause handling flag
 397         int paused = 0;
 398
 399         // Special case ffwd handling
 400         int ignore = 0;
 401
 402         // Current time calcs
 403         double current_time = mlt_properties_get_double( properties, "current_time" );
 404
 405         // We may want to use the source fps if available
 406         double source_fps = mlt_properties_get_double( properties, "source_fps" );
 407
 408         // Set the result arguments that we know here (only *buffer is now required)
 409         *format = mlt_image_yuv422;
 410         *width = codec_context->width;
 411         *height = codec_context->height;
 412
 413         // Set this on the frame properties
 414         mlt_properties_set_int( frame_properties, "width", *width );
 415         mlt_properties_set_int( frame_properties, "height", *height );
 416
 417         // Lock the mutex now
 418         pthread_mutex_lock( &avformat_mutex );
 419
 420         // Construct an AVFrame for YUV422 conversion
 421         if ( output == NULL )
 422         {
 423                 int size = avpicture_get_size( PIX_FMT_YUV422, *width, *height );
 424                 size += *width * 2;
 425                 uint8_t *buf = mlt_pool_alloc( size );
 426                 output = mlt_pool_alloc( sizeof( AVPicture ) );
 427                 //memset( output, 0, sizeof( AVPicture ) );
 428                 avpicture_fill( output, buf, PIX_FMT_YUV422, *width, *height );
 429                 mlt_properties_set_data( properties, "video_output_frame", output, 0, ( mlt_destructor )mlt_pool_release, NULL );
 430                 mlt_properties_set_data( properties, "video_output_buffer", buf, 0, ( mlt_destructor )mlt_pool_release, NULL );
 431         }
 432
 433         // Seek if necessary
 434         if ( position != expected )
 435         {
 436                 if ( position + 1 == expected )
 437                 {
 438                         // We're paused - use last image
 439                         paused = 1;
 440                 }
 441                 else if ( position > expected && ( position - expected ) < 250 )
 442                 {
 443                         // Fast forward - seeking is inefficient for small distances - just ignore following frames
 444                         ignore = position - expected;
 445                 }
 446                 else
 447                 {
 448                         // Set to the real timecode
 449                         av_seek_frame( context, -1, real_timecode * 1000000.0 );
 450
 451                         // Remove the cached info relating to the previous position
 452                         mlt_properties_set_double( properties, "current_time", real_timecode );
 453                         mlt_properties_set_data( properties, "current_image", NULL, 0, NULL, NULL );
 454                 }
 455         }
 456
 457         // Duplicate the last image if necessary
 458         if ( mlt_properties_get_data( properties, "current_image", NULL ) != NULL &&
 459                  ( paused || mlt_properties_get_double( properties, "current_time" ) >= real_timecode ) )
 460         {
 461                 // Get current image and size
 462                 int size = 0;
 463                 uint8_t *image = mlt_properties_get_data( properties, "current_image", &size );
 464
 465                 // Duplicate it
 466                 *buffer = mlt_pool_alloc( size );
 467                 memcpy( *buffer, image, size );
 468
 469                 // Set this on the frame properties
 470                 mlt_properties_set_data( frame_properties, "image", *buffer, size, ( mlt_destructor )mlt_pool_release, NULL );
 471         }
 472         else
 473         {
 474                 int ret = 0;
 475                 int got_picture = 0;
 476                 AVFrame frame;
 477
 478                 memset( &pkt, 0, sizeof( pkt ) );
 479                 memset( &frame, 0, sizeof( frame ) );
 480
 481                 while( ret >= 0 && !got_picture )
 482                 {
 483                         // Read a packet
 484                         ret = av_read_frame( context, &pkt );
 485
 486                         // We only deal with video from the selected video_index
 487                         if ( ret >= 0 && pkt.stream_index == index && pkt.size > 0 )
 488                         {
 489                                 // Decode the image
 490                                 ret = avcodec_decode_video( codec_context, &frame, &got_picture, pkt.data, pkt.size );
 491
 492                                 if ( got_picture )
 493                                 {
 494                                         if ( pkt.pts != AV_NOPTS_VALUE && pkt.pts != 0  )
 495                                                 current_time = ( double )pkt.pts / 1000000.0;
 496                                         else
 497                                                 current_time = real_timecode;
 498
 499                                         // Handle ignore
 500                                         if ( current_time < real_timecode )
 501                                         {
 502                                                 ignore = 0;
 503                                                 got_picture = 0;
 504                                         }
 505                                         else if ( current_time >= real_timecode )
 506                                         {
 507                                                 //current_time = real_timecode;
 508                                                 ignore = 0;
 509                                         }
 510                                         else if ( ignore -- )
 511                                         {
 512                                                 got_picture = 0;
 513                                         }
 514                                 }
 515                         }
 516
 517                         // We're finished with this packet regardless
 518                         av_free_packet( &pkt );
 519                 }
 520
 521                 // Now handle the picture if we have one
 522                 if ( got_picture )
 523                 {
 524                         // Get current image and size
 525                         int size = 0;
 526                         uint8_t *image = mlt_properties_get_data( properties, "current_image", &size );
 527
 528                         if ( image == NULL || size != *width * *height * 2 )
 529                         {
 530                                 size = *width * ( *height + 1 ) * 2;
 531                                 image = mlt_pool_alloc( size );
 532                                 mlt_properties_set_data( properties, "current_image", image, size, ( mlt_destructor )mlt_pool_release, NULL );
 533                         }
 534
 535                         *buffer = mlt_pool_alloc( size );
 536
 537                         // EXPERIMENTAL IMAGE NORMALISATIONS
 538                         if ( codec_context->pix_fmt == PIX_FMT_YUV420P )
 539                         {
 540                                 register int i, j;
 541                                 register int half = *width >> 1;
 542                                 register uint8_t *Y = ( ( AVPicture * )&frame )->data[ 0 ];
 543                                 register uint8_t *U = ( ( AVPicture * )&frame )->data[ 1 ];
 544                                 register uint8_t *V = ( ( AVPicture * )&frame )->data[ 2 ];
 545                                 register uint8_t *d = *buffer;
 546                                 register uint8_t *y, *u, *v;
 547
 548                                 i = *height >> 1;
 549                                 while ( i -- )
 550                                 {
 551                                         y = Y;
 552                                         u = U;
 553                                         v = V;
 554                                         j = half;
 555                                         while ( j -- )
 556                                         {
 557                                                 *d ++ = *y ++;
 558                                                 *d ++ = *u ++;
 559                                                 *d ++ = *y ++;
 560                                                 *d ++ = *v ++;
 561                                         }
 562
 563                                         Y += ( ( AVPicture * )&frame )->linesize[ 0 ];
 564                                         y = Y;
 565                                         u = U;
 566                                         v = V;
 567                                         j = half;
 568                                         while ( j -- )
 569                                         {
 570                                                 *d ++ = *y ++;
 571                                                 *d ++ = *u ++;
 572                                                 *d ++ = *y ++;
 573                                                 *d ++ = *v ++;
 574                                         }
 575
 576                                         Y += ( ( AVPicture * )&frame )->linesize[ 0 ];
 577                                         U += ( ( AVPicture * )&frame )->linesize[ 1 ];
 578                                         V += ( ( AVPicture * )&frame )->linesize[ 2 ];
 579                                 }
 580                         }
 581                         else
 582                         {
 583                                 img_convert( output, PIX_FMT_YUV422, (AVPicture *)&frame, codec_context->pix_fmt, *width, *height );
 584                                 memcpy( *buffer, output->data[ 0 ], size );
 585                         }
 586
 587                         memcpy( image, *buffer, size );
 588                         mlt_properties_set_data( frame_properties, "image", *buffer, size, ( mlt_destructor )mlt_pool_release, NULL );
 589
 590                         if ( current_time == 0 && source_fps != 0 )
 591                         {
 592                                 double fps = mlt_properties_get_double( properties, "fps" );
 593                                 current_time = ceil( source_fps * ( double )position / fps ) * ( 1 / source_fps );
 594                                 mlt_properties_set_double( properties, "current_time", current_time );
 595                         }
 596                         else
 597                         {
 598                                 mlt_properties_set_double( properties, "current_time", current_time );
 599                         }
 600                 }
 601         }
 602
 603         // Regardless of speed, we expect to get the next frame (cos we ain't too bright)
 604         mlt_properties_set_position( properties, "video_expected", position + 1 );
 605
 606         // Unlock the mutex now
 607         pthread_mutex_unlock( &avformat_mutex );
 608
 609         return 0;
 610 }
 611
 612 /** Set up video handling.
 613 */
 614
 615 static void producer_set_up_video( mlt_producer this, mlt_frame frame )
 616 {
 617         // Get the properties
 618         mlt_properties properties = mlt_producer_properties( this );
 619
 620         // Fetch the video_context
 621         AVFormatContext *context = mlt_properties_get_data( properties, "video_context", NULL );
 622
 623         // Get the video_index
 624         int index = mlt_properties_get_int( properties, "video_index" );
 625
 626         // Get the frame properties
 627         mlt_properties frame_properties = mlt_frame_properties( frame );
 628
 629         // Lock the mutex now
 630         pthread_mutex_lock( &avformat_mutex );
 631
 632         if ( context != NULL && index != -1 )
 633         {
 634                 // Get the video stream
 635                 AVStream *stream = context->streams[ index ];
 636
 637                 // Get codec context
 638                 AVCodecContext *codec_context = &stream->codec;
 639
 640                 // Get the codec
 641                 AVCodec *codec = mlt_properties_get_data( properties, "video_codec", NULL );
 642
 643                 // Initialise the codec if necessary
 644                 if ( codec == NULL )
 645                 {
 646                         // Find the codec
 647                         codec = avcodec_find_decoder( codec_context->codec_id );
 648
 649                         // If we don't have a codec and we can't initialise it, we can't do much more...
 650                         if ( codec != NULL && avcodec_open( codec_context, codec ) >= 0 )
 651                         {
 652                                 // Now store the codec with its destructor
 653                                 mlt_properties_set_data( properties, "video_codec", codec_context, 0, producer_codec_close, NULL );
 654                         }
 655                         else
 656                         {
 657                                 // Remember that we can't use this later
 658                                 mlt_properties_set_int( properties, "video_index", -1 );
 659                         }
 660                 }
 661
 662                 // No codec, no show...
 663                 if ( codec != NULL )
 664                 {
 665                         double aspect_ratio = 1;
 666                         double source_fps = 0;
 667
 668                         // Set aspect ratio
 669                         if ( codec_context->sample_aspect_ratio.num > 0 )
 670                                 aspect_ratio = av_q2d( codec_context->sample_aspect_ratio );
 671
 672                         mlt_properties_set_double( properties, "aspect_ratio", aspect_ratio );
 673                         //fprintf( stderr, "AVFORMAT: sample aspect %f %dx%d\n", av_q2d( codec_context->sample_aspect_ratio ), codec_context->width, codec_context->height );
 674
 675                         // Determine the fps
 676                         source_fps = ( double )codec_context->frame_rate / ( codec_context->frame_rate_base == 0 ? 1 : codec_context->frame_rate_base );
 677
 678                         // We'll use fps if it's available
 679                         if ( source_fps > 0 && source_fps < 30 )
 680                                 mlt_properties_set_double( properties, "source_fps", source_fps );
 681
 682                         // Set the width and height
 683                         mlt_properties_set_int( frame_properties, "width", codec_context->width );
 684                         mlt_properties_set_int( frame_properties, "height", codec_context->height );
 685
 686                         mlt_frame_push_get_image( frame, producer_get_image );
 687                         mlt_properties_set_data( frame_properties, "avformat_producer", this, 0, NULL, NULL );
 688                 }
 689                 else
 690                 {
 691                         mlt_properties_set_int( frame_properties, "test_image", 1 );
 692                 }
 693         }
 694         else
 695         {
 696                 mlt_properties_set_int( frame_properties, "test_image", 1 );
 697         }
 698
 699         // Unlock the mutex now
 700         pthread_mutex_unlock( &avformat_mutex );
 701 }
 702
 703 /** Get the audio from a frame.
 704 */
 705
 706 static int producer_get_audio( mlt_frame frame, int16_t **buffer, mlt_audio_format *format, int *frequency, int *channels, int *samples )
 707 {
 708         // Get the properties from the frame
 709         mlt_properties frame_properties = mlt_frame_properties( frame );
 710
 711         // Obtain the frame number of this frame
 712         mlt_position position = mlt_properties_get_position( frame_properties, "avformat_position" );
 713
 714         // Get the producer
 715         mlt_producer this = mlt_properties_get_data( frame_properties, "avformat_producer", NULL );
 716
 717         // Get the producer properties
 718         mlt_properties properties = mlt_producer_properties( this );
 719
 720         // Fetch the audio_context
 721         AVFormatContext *context = mlt_properties_get_data( properties, "audio_context", NULL );
 722
 723         // Get the audio_index
 724         int index = mlt_properties_get_int( properties, "audio_index" );
 725
 726         // Obtain the expected frame numer
 727         mlt_position expected = mlt_properties_get_position( properties, "audio_expected" );
 728
 729         // Obtain the resample context if it exists (not always needed)
 730         ReSampleContext *resample = mlt_properties_get_data( properties, "audio_resample", NULL );
 731
 732         // Obtain the audio buffer
 733         int16_t *audio_buffer = mlt_properties_get_data( properties, "audio_buffer", NULL );
 734
 735         // Get amount of audio used
 736         int audio_used =  mlt_properties_get_int( properties, "audio_used" );
 737
 738         // Calculate the real time code
 739         double real_timecode = producer_time_of_frame( this, position );
 740
 741         // Get the audio stream
 742         AVStream *stream = context->streams[ index ];
 743
 744         // Get codec context
 745         AVCodecContext *codec_context = &stream->codec;
 746
 747         // Packet
 748         AVPacket pkt;
 749
 750         // Number of frames to ignore (for ffwd)
 751         int ignore = 0;
 752
 753         // Flag for paused (silence)
 754         int paused = 0;
 755         int locked = 0;
 756
 757         // Lock the mutex now
 758         pthread_mutex_lock( &avformat_mutex );
 759
 760         // Check for resample and create if necessary
 761         if ( resample == NULL )
 762         {
 763                 // Create the resampler
 764                 resample = audio_resample_init( *channels, codec_context->channels, *frequency, codec_context->sample_rate );
 765
 766                 // And store it on properties
 767                 mlt_properties_set_data( properties, "audio_resample", resample, 0, ( mlt_destructor )audio_resample_close, NULL );
 768         }
 769
 770         // Check for audio buffer and create if necessary
 771         if ( audio_buffer == NULL )
 772         {
 773                 // Allocate the audio buffer
 774                 audio_buffer = mlt_pool_alloc( AVCODEC_MAX_AUDIO_FRAME_SIZE * sizeof( int16_t ) );
 775
 776                 // And store it on properties for reuse
 777                 mlt_properties_set_data( properties, "audio_buffer", audio_buffer, 0, ( mlt_destructor )mlt_pool_release, NULL );
 778         }
 779
 780         // Seek if necessary
 781         if ( position != expected )
 782         {
 783                 if ( position + 1 == expected )
 784                 {
 785                         // We're paused - silence required
 786                         paused = 1;
 787                 }
 788                 else if ( position > expected && ( position - expected ) < 250 )
 789                 {
 790                         // Fast forward - seeking is inefficient for small distances - just ignore following frames
 791                         ignore = position - expected;
 792                 }
 793                 else
 794                 {
 795                         // Set to the real timecode
 796                         av_seek_frame( context, -1, real_timecode * 1000000.0 );
 797
 798                         // Clear the usage in the audio buffer
 799                         audio_used = 0;
 800
 801                         locked = 1;
 802                 }
 803         }
 804
 805         // Get the audio if required
 806         if ( !paused )
 807         {
 808                 int ret = 0;
 809                 int got_audio = 0;
 810                 int16_t *temp = mlt_pool_alloc( sizeof( int16_t ) * AVCODEC_MAX_AUDIO_FRAME_SIZE );
 811
 812                 memset( &pkt, 0, sizeof( pkt ) );
 813
 814                 while( ret >= 0 && !got_audio )
 815                 {
 816                         // Check if the buffer already contains the samples required
 817                         if ( audio_used >= *samples && ignore == 0 )
 818                         {
 819                                 got_audio = 1;
 820                                 break;
 821                         }
 822
 823                         // Read a packet
 824                         ret = av_read_frame( context, &pkt );
 825
 826                 int len = pkt.size;
 827                 uint8_t *ptr = pkt.data;
 828                         int data_size;
 829
 830                         // We only deal with video from the selected video_index
 831                         while ( ptr != NULL && ret >= 0 && pkt.stream_index == index && len > 0 )
 832                         {
 833                                 // Decode the audio
 834                                 ret = avcodec_decode_audio( codec_context, temp, &data_size, ptr, len );
 835
 836                                 if ( ret < 0 )
 837                                 {
 838                                         ret = 0;
 839                                         break;
 840                                 }
 841
 842                                 len -= ret;
 843                                 ptr += ret;
 844
 845                                 if ( data_size > 0 )
 846                                 {
 847                                         int size_out = audio_resample( resample, &audio_buffer[ audio_used * *channels ], temp, data_size / ( codec_context->channels * sizeof( int16_t ) ) );
 848
 849                                         audio_used += size_out;
 850
 851                                         // Handle ignore
 852                                         while ( ignore && audio_used > *samples )
 853                                         {
 854                                                 ignore --;
 855                                                 audio_used -= *samples;
 856                                                 memmove( audio_buffer, &audio_buffer[ *samples * *channels ], audio_used * sizeof( int16_t ) );
 857                                         }
 858                                 }
 859
 860                                 // If we're behind, ignore this packet
 861                                 float current_pts = (float)pkt.pts / 1000000.0;
 862                                 double discrepancy = mlt_properties_get_double( properties, "discrepancy" );
 863                                 if ( current_pts != 0 && real_timecode != 0 )
 864                                 {
 865                                         if ( discrepancy != 1 )
 866                                                 discrepancy = ( discrepancy + ( real_timecode / current_pts ) ) / 2;
 867                                         else
 868                                                 discrepancy = real_timecode / current_pts;
 869                                         if ( discrepancy > 0.9 && discrepancy < 1.1 )
 870                                                 discrepancy = 1.0;
 871                                         else
 872                                                 discrepancy = floor( discrepancy + 0.5 );
 873
 874                                         if ( discrepancy == 0 )
 875                                                 discrepancy = 1.0;
 876
 877                                         mlt_properties_set_double( properties, "discrepancy", discrepancy );
 878                                 }
 879
 880                                 if ( !ignore && discrepancy * current_pts <= ( real_timecode - 0.02 ) )
 881                                         ignore = 1;
 882                         }
 883
 884                         // We're finished with this packet regardless
 885                         av_free_packet( &pkt );
 886                 }
 887
 888                 *buffer = mlt_pool_alloc( *samples * *channels * sizeof( int16_t ) );
 889                 mlt_properties_set_data( frame_properties, "audio", *buffer, 0, ( mlt_destructor )mlt_pool_release, NULL );
 890
 891                 // Now handle the audio if we have enough
 892                 if ( audio_used >= *samples )
 893                 {
 894                         memcpy( *buffer, audio_buffer, *samples * *channels * sizeof( int16_t ) );
 895                         audio_used -= *samples;
 896                         memmove( audio_buffer, &audio_buffer[ *samples * *channels ], audio_used * *channels * sizeof( int16_t ) );
 897                 }
 898                 else
 899                 {
 900                         memset( *buffer, 0, *samples * *channels * sizeof( int16_t ) );
 901                 }
 902
 903                 // Store the number of audio samples still available
 904                 mlt_properties_set_int( properties, "audio_used", audio_used );
 905
 906                 // Release the temporary audio
 907                 mlt_pool_release( temp );
 908         }
 909         else
 910         {
 911                 // Get silence and don't touch the context
 912                 frame->get_audio = NULL;
 913                 mlt_frame_get_audio( frame, buffer, format, frequency, channels, samples );
 914         }
 915
 916         // Regardless of speed, we expect to get the next frame (cos we ain't too bright)
 917         mlt_properties_set_position( properties, "audio_expected", position + 1 );
 918
 919         // Unlock the mutex now
 920         pthread_mutex_unlock( &avformat_mutex );
 921
 922         return 0;
 923 }
 924
 925 /** Set up audio handling.
 926 */
 927
 928 static void producer_set_up_audio( mlt_producer this, mlt_frame frame )
 929 {
 930         // Get the properties
 931         mlt_properties properties = mlt_producer_properties( this );
 932
 933         // Fetch the audio_context
 934         AVFormatContext *context = mlt_properties_get_data( properties, "audio_context", NULL );
 935
 936         // Get the audio_index
 937         int index = mlt_properties_get_int( properties, "audio_index" );
 938
 939         // Lock the mutex now
 940         pthread_mutex_lock( &avformat_mutex );
 941
 942         // Deal with audio context
 943         if ( context != NULL && index != -1 )
 944         {
 945                 // Get the frame properties
 946                 mlt_properties frame_properties = mlt_frame_properties( frame );
 947
 948                 // Get the audio stream
 949                 AVStream *stream = context->streams[ index ];
 950
 951                 // Get codec context
 952                 AVCodecContext *codec_context = &stream->codec;
 953
 954                 // Get the codec
 955                 AVCodec *codec = mlt_properties_get_data( properties, "audio_codec", NULL );
 956
 957                 // Initialise the codec if necessary
 958                 if ( codec == NULL )
 959                 {
 960                         // Find the codec
 961                         codec = avcodec_find_decoder( codec_context->codec_id );
 962
 963                         // If we don't have a codec and we can't initialise it, we can't do much more...
 964                         if ( codec != NULL && avcodec_open( codec_context, codec ) >= 0 )
 965                         {
 966                                 // Now store the codec with its destructor
 967                                 mlt_properties_set_data( properties, "audio_codec", codec_context, 0, producer_codec_close, NULL );
 968
 969                         }
 970                         else
 971                         {
 972                                 // Remember that we can't use this later
 973                                 mlt_properties_set_int( properties, "audio_index", -1 );
 974                         }
 975                 }
 976
 977                 // No codec, no show...
 978                 if ( codec != NULL )
 979                 {
 980                         frame->get_audio = producer_get_audio;
 981                         mlt_properties_set_data( frame_properties, "avformat_producer", this, 0, NULL, NULL );
 982                 }
 983         }
 984
 985         // Unlock the mutex now
 986         pthread_mutex_unlock( &avformat_mutex );
 987 }
 988
 989 /** Our get frame implementation.
 990 */
 991
 992 static int producer_get_frame( mlt_producer this, mlt_frame_ptr frame, int index )
 993 {
 994         // Create an empty frame
 995         *frame = mlt_frame_init( );
 996
 997         // Update timecode on the frame we're creating
 998         mlt_frame_set_position( *frame, mlt_producer_position( this ) );
 999
1000         // Set the position of this producer
1001         mlt_properties_set_position( mlt_frame_properties( *frame ), "avformat_position", mlt_producer_get_in( this ) + mlt_producer_position( this ) );
1002
1003         // Set up the video
1004         producer_set_up_video( this, *frame );
1005
1006         // Set up the audio
1007         producer_set_up_audio( this, *frame );
1008
1009         // Set the aspect_ratio
1010         mlt_properties_set_double( mlt_frame_properties( *frame ), "aspect_ratio", mlt_properties_get_double( mlt_producer_properties( this ), "aspect_ratio" ) );
1011
1012         // Calculate the next timecode
1013         mlt_producer_prepare_next( this );
1014
1015         return 0;
1016 }