research.m1stereo.tv/gitweb/ - melted/blob - src/modules/ffmpeg/filter_ffmpeg_dub.c

   1 /*
   2  * filter_ffmpeg_dub.c -- simple ffmpeg dub test case
   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 #include "filter_ffmpeg_dub.h"
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <framework/mlt.h>
  25
  26 /** Do it.
  27 */
  28
  29 static int filter_get_audio( mlt_frame frame, int16_t **buffer, mlt_audio_format *format, int *frequency, int *channels, int *samples )
  30 {
  31         // Obtain the frame properties
  32         mlt_properties frame_properties = mlt_frame_properties( frame );
  33
  34         // Get the producer used.
  35         mlt_producer producer = mlt_properties_get_data( frame_properties, "producer", NULL );
  36
  37         // Get the producer properties
  38         mlt_properties producer_properties = mlt_producer_properties( producer );
  39
  40         // Get the original get_audio
  41         frame->get_audio = mlt_properties_get_data( frame_properties, "get_audio", NULL );
  42
  43         // Call the original get_audio
  44         mlt_frame_get_audio( frame, buffer, format, frequency, channels, samples );
  45
  46         // Now if our producer is still producing, override the audio
  47         if ( !mlt_properties_get_int( producer_properties, "end_of_clip" ) )
  48         {
  49                 // Get the position
  50                 mlt_position position = mlt_properties_get_position( producer_properties, "dub_position" );
  51
  52                 // We need a frame from the producer
  53                 mlt_frame producer_frame;
  54
  55                 // Set the FPS
  56                 mlt_properties_set_double( producer_properties, "fps", mlt_properties_get_double( frame_properties, "fps" ) );
  57
  58                 // Seek to the position
  59                 mlt_producer_seek( producer, position );
  60
  61                 // Get the next frame
  62                 producer->get_frame( producer, &producer_frame, 0 );
  63
  64                 if ( !mlt_properties_get_int( producer_properties, "end_of_clip" ) )
  65                 {
  66                         // Now get the audio from this frame
  67                         producer_frame->get_audio( producer_frame, buffer, format, frequency, channels, samples );
  68
  69                         // This producer frame will be destroyed automatically when frame is destroyed
  70                         mlt_properties_set_data( frame_properties, "ffmpeg_dub_frame", producer_frame, 0, ( mlt_destructor )mlt_frame_close, NULL );
  71
  72                         // Incrment the position
  73                         mlt_properties_set_position( producer_properties, "dub_position", position + 1 );
  74                 }
  75         }
  76
  77         return 0;
  78 }
  79
  80 /** Filter processing.
  81 */
  82
  83 static mlt_frame filter_process( mlt_filter this, mlt_frame frame )
  84 {
  85         // Obtain the filter properties
  86         mlt_properties filter_properties = mlt_filter_properties( this );
  87
  88         // Get the producer used.
  89         mlt_producer producer = mlt_properties_get_data( filter_properties, "producer", NULL );
  90
  91         // Obtain the frame properties
  92         mlt_properties frame_properties = mlt_frame_properties( frame );
  93
  94         // Get the producer properties
  95         mlt_properties producer_properties = mlt_producer_properties( producer );
  96
  97         // Only do this if we have not reached end of clip and ffmpeg_dub has not already been done
  98         if ( !mlt_properties_get_int( producer_properties, "end_of_clip" ) &&
  99                  mlt_properties_get_data( frame_properties, "get_audio", NULL ) == NULL )
 100         {
 101                 // Backup the original get_audio (it's still needed)
 102                 mlt_properties_set_data( frame_properties, "get_audio", frame->get_audio, 0, NULL, NULL );
 103
 104                 // Pass the producer on the frame
 105                 mlt_properties_set_data( frame_properties, "producer", producer, 0, NULL, NULL );
 106
 107                 // Override the get_audio method
 108                 frame->get_audio = filter_get_audio;
 109         }
 110
 111         return frame;
 112 }
 113
 114 /** Constructor for the filter.
 115 */
 116
 117 mlt_filter filter_ffmpeg_dub_init( char *file )
 118 {
 119         // Create the filter object
 120         mlt_filter this = calloc( sizeof( struct mlt_filter_s ), 1 );
 121
 122         // Initialise it
 123         mlt_filter_init( this, NULL );
 124
 125         // Overide the filter process method
 126         this->process = filter_process;
 127
 128         // Obtain the properties
 129         mlt_properties properties = mlt_filter_properties( this );
 130
 131         // Create an ffmpeg producer
 132         mlt_producer producer = mlt_factory_producer( "ffmpeg", file );
 133
 134         // Pass the producer
 135         mlt_properties_set_data( properties, "producer", producer, 0, ( mlt_destructor )mlt_producer_close, NULL );
 136
 137         // Initialise the audio frame position
 138         mlt_properties_set_position( properties, "dub_position", 0 );
 139
 140         return this;
 141 }
 142