3 * \brief interface for all frame classes
6 * Copyright (C) 2003-2009 Ushodaya Enterprises Limited
7 * \author Charles Yates <charles.yates@pandora.be>
9 * This library is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
14 * This library is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with this library; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24 #include "mlt_frame.h"
25 #include "mlt_producer.h"
26 #include "mlt_factory.h"
27 #include "mlt_profile.h"
34 /** Construct a frame object.
36 * \public \memberof mlt_frame_s
37 * \param service the pointer to any service that can provide access to the profile
38 * \return a frame object on success or NULL if there was an allocation error
41 mlt_frame mlt_frame_init( mlt_service service )
44 mlt_frame self = calloc( 1, sizeof( struct mlt_frame_s ) );
48 mlt_profile profile = mlt_service_profile( service );
50 // Initialise the properties
51 mlt_properties properties = &self->parent;
52 mlt_properties_init( properties, self );
54 // Set default properties on the frame
55 mlt_properties_set_position( properties, "_position", 0.0 );
56 mlt_properties_set_data( properties, "image", NULL, 0, NULL, NULL );
57 mlt_properties_set_int( properties, "width", profile? profile->width : 720 );
58 mlt_properties_set_int( properties, "height", profile? profile->height : 576 );
59 mlt_properties_set_double( properties, "aspect_ratio", mlt_profile_sar( NULL ) );
60 mlt_properties_set_data( properties, "audio", NULL, 0, NULL, NULL );
61 mlt_properties_set_data( properties, "alpha", NULL, 0, NULL, NULL );
63 // Construct stacks for frames and methods
64 self->stack_image = mlt_deque_init( );
65 self->stack_audio = mlt_deque_init( );
66 self->stack_service = mlt_deque_init( );
72 /** Get a frame's properties.
74 * \public \memberof mlt_frame_s
76 * \return the frame's properties or NULL if an invalid frame is supplied
79 mlt_properties mlt_frame_properties( mlt_frame self )
81 return self != NULL ? &self->parent : NULL;
84 /** Determine if the frame will produce a test card image.
86 * \public \memberof mlt_frame_s
88 * \return true (non-zero) if this will produce from a test card
91 int mlt_frame_is_test_card( mlt_frame self )
93 return mlt_deque_count( self->stack_image ) == 0 || mlt_properties_get_int( MLT_FRAME_PROPERTIES( self ), "test_image" );
96 /** Determine if the frame will produce audio from a test card.
98 * \public \memberof mlt_frame_s
100 * \return true (non-zero) if this will produce from a test card
103 int mlt_frame_is_test_audio( mlt_frame self )
105 return mlt_deque_count( self->stack_audio ) == 0 || mlt_properties_get_int( MLT_FRAME_PROPERTIES( self ), "test_audio" );
108 /** Get the sample aspect ratio of the frame.
110 * \public \memberof mlt_frame_s
111 * \param self a frame
112 * \return the aspect ratio
115 double mlt_frame_get_aspect_ratio( mlt_frame self )
117 return mlt_properties_get_double( MLT_FRAME_PROPERTIES( self ), "aspect_ratio" );
120 /** Set the sample aspect ratio of the frame.
122 * \public \memberof mlt_frame_s
123 * \param self a frame
124 * \param value the new image sample aspect ratio
125 * \return true if error
128 int mlt_frame_set_aspect_ratio( mlt_frame self, double value )
130 return mlt_properties_set_double( MLT_FRAME_PROPERTIES( self ), "aspect_ratio", value );
133 /** Get the time position of this frame.
135 * This position is not necessarily the position as the original
136 * producer knows it. It could be the position that the playlist,
137 * multitrack, or tractor producer set.
139 * \public \memberof mlt_frame_s
140 * \param self a frame
141 * \return the position
142 * \see mlt_frame_original_position
145 mlt_position mlt_frame_get_position( mlt_frame self )
147 int pos = mlt_properties_get_position( MLT_FRAME_PROPERTIES( self ), "_position" );
148 return pos < 0 ? 0 : pos;
151 /** Get the original time position of this frame.
153 * This is the position that the original producer set on the frame.
155 * \public \memberof mlt_frame_s
156 * \param self a frame
157 * \return the position
160 mlt_position mlt_frame_original_position( mlt_frame self )
162 int pos = mlt_properties_get_position( MLT_FRAME_PROPERTIES( self ), "original_position" );
163 return pos < 0 ? 0 : pos;
166 /** Set the time position of this frame.
168 * \public \memberof mlt_frame_s
169 * \param self a frame
170 * \param value the position
171 * \return true if error
174 int mlt_frame_set_position( mlt_frame self, mlt_position value )
176 // Only set the original_position the first time.
177 if ( ! mlt_properties_get( MLT_FRAME_PROPERTIES( self ), "original_position" ) )
178 mlt_properties_set_position( MLT_FRAME_PROPERTIES( self ), "original_position", value );
179 return mlt_properties_set_position( MLT_FRAME_PROPERTIES( self ), "_position", value );
182 /** Stack a get_image callback.
184 * \public \memberof mlt_frame_s
185 * \param self a frame
186 * \param the get_image callback
187 * \return true if error
190 int mlt_frame_push_get_image( mlt_frame self, mlt_get_image get_image )
192 return mlt_deque_push_back( self->stack_image, get_image );
195 /** Pop a get_image callback.
197 * \public \memberof mlt_frame_s
198 * \param self a frame
199 * \return the get_image callback
202 mlt_get_image mlt_frame_pop_get_image( mlt_frame self )
204 return mlt_deque_pop_back( self->stack_image );
209 * \public \memberof mlt_frame_s
210 * \param self a frame
211 * \param that the frame to push onto \p self
212 * \return true if error
215 int mlt_frame_push_frame( mlt_frame self, mlt_frame that )
217 return mlt_deque_push_back( self->stack_image, that );
222 * \public \memberof mlt_frame_s
223 * \param self a frame
224 * \return a frame that was previously pushed
227 mlt_frame mlt_frame_pop_frame( mlt_frame self )
229 return mlt_deque_pop_back( self->stack_image );
234 * \public \memberof mlt_frame_s
235 * \param self a frame
236 * \param that an opaque pointer
237 * \return true if error
240 int mlt_frame_push_service( mlt_frame self, void *that )
242 return mlt_deque_push_back( self->stack_image, that );
247 * \public \memberof mlt_frame_s
248 * \param self a frame
249 * \return an opaque pointer to something previously pushed
252 void *mlt_frame_pop_service( mlt_frame self )
254 return mlt_deque_pop_back( self->stack_image );
259 * \public \memberof mlt_frame_s
260 * \param self a frame
261 * \param that an integer
262 * \return true if error
265 int mlt_frame_push_service_int( mlt_frame self, int that )
267 return mlt_deque_push_back_int( self->stack_image, that );
272 * \public \memberof mlt_frame_s
273 * \param self a frame
274 * \return an integer that was previously pushed
277 int mlt_frame_pop_service_int( mlt_frame self )
279 return mlt_deque_pop_back_int( self->stack_image );
282 /** Push an audio item on the stack.
284 * \public \memberof mlt_frame_s
285 * \param self a frame
286 * \param that an opaque pointer
287 * \return true if error
290 int mlt_frame_push_audio( mlt_frame self, void *that )
292 return mlt_deque_push_back( self->stack_audio, that );
295 /** Pop an audio item from the stack
297 * \public \memberof mlt_frame_s
298 * \param self a frame
299 * \return an opaque pointer to something that was pushed onto the frame's audio stack
302 void *mlt_frame_pop_audio( mlt_frame self )
304 return mlt_deque_pop_back( self->stack_audio );
307 /** Return the service stack
309 * \public \memberof mlt_frame_s
310 * \param self a frame
311 * \return the service stack
314 mlt_deque mlt_frame_service_stack( mlt_frame self )
316 return self->stack_service;
319 /** Set a new image on the frame.
321 * \public \memberof mlt_frame_s
322 * \param self a frame
323 * \param image a pointer to the raw image data
324 * \param size the size of the image data in bytes (optional)
325 * \param destroy a function to deallocate \p image when the frame is closed (optional)
326 * \return true if error
329 int mlt_frame_set_image( mlt_frame self, uint8_t *image, int size, mlt_destructor destroy )
331 return mlt_properties_set_data( MLT_FRAME_PROPERTIES( self ), "image", image, size, destroy, NULL );
334 /** Set a new alpha channel on the frame.
336 * \public \memberof mlt_frame_s
337 * \param self a frame
338 * \param alpha a pointer to the alpha channel
339 * \param size the size of the alpha channel in bytes (optional)
340 * \param destroy a function to deallocate \p alpha when the frame is closed (optional)
341 * \return true if error
344 int mlt_frame_set_alpha( mlt_frame self, uint8_t *alpha, int size, mlt_destructor destroy )
346 self->get_alpha_mask = NULL;
347 return mlt_properties_set_data( MLT_FRAME_PROPERTIES( self ), "alpha", alpha, size, destroy, NULL );
350 /** Replace image stack with the information provided.
352 * This might prove to be unreliable and restrictive - the idea is that a transition
353 * which normally uses two images may decide to only use the b frame (ie: in the case
354 * of a composite where the b frame completely obscures the a frame).
356 * The image must be writable and the destructor for the image itself must be taken
357 * care of on another frame and that frame cannot have a replace applied to it...
358 * Further it assumes that no alpha mask is in use.
360 * For these reasons, it can only be used in a specific situation - when you have
361 * multiple tracks each with their own transition and these transitions are applied
362 * in a strictly reversed order (ie: highest numbered [lowest track] is processed
365 * More reliable approach - the cases should be detected during the process phase
366 * and the upper tracks should simply not be invited to stack...
368 * \public \memberof mlt_frame_s
369 * \param self a frame
370 * \param image a new image
371 * \param format the image format
372 * \param width the width of the new image
373 * \param height the height of the new image
376 void mlt_frame_replace_image( mlt_frame self, uint8_t *image, mlt_image_format format, int width, int height )
378 // Remove all items from the stack
379 while( mlt_deque_pop_back( self->stack_image ) ) ;
381 // Update the information
382 mlt_properties_set_data( MLT_FRAME_PROPERTIES( self ), "image", image, 0, NULL, NULL );
383 mlt_properties_set_int( MLT_FRAME_PROPERTIES( self ), "width", width );
384 mlt_properties_set_int( MLT_FRAME_PROPERTIES( self ), "height", height );
385 mlt_properties_set_int( MLT_FRAME_PROPERTIES( self ), "format", format );
386 self->get_alpha_mask = NULL;
389 /** Get the short name for an image format.
391 * \public \memberof mlt_frame_s
392 * \param format the image format
396 const char * mlt_image_format_name( mlt_image_format format )
400 case mlt_image_none: return "none";
401 case mlt_image_rgb24: return "rgb24";
402 case mlt_image_rgb24a: return "rgb24a";
403 case mlt_image_yuv422: return "yuv422";
404 case mlt_image_yuv420p: return "yuv420p";
405 case mlt_image_opengl: return "opengl";
410 /** Get the number of bytes needed for an image.
412 * \public \memberof mlt_frame_s
413 * \param format the image format
414 * \param width width of the image in pixels
415 * \param height height of the image in pixels
416 * \param[out] bpp the number of bytes per pixel (optional)
417 * \return the number of bytes
419 int mlt_image_format_size( mlt_image_format format, int width, int height, int *bpp )
427 case mlt_image_rgb24:
429 return width * height * 3;
430 case mlt_image_opengl:
431 case mlt_image_rgb24a:
433 return width * height * 4;
434 case mlt_image_yuv422:
436 return width * height * 2;
437 case mlt_image_yuv420p:
438 if ( bpp ) *bpp = 3 / 2;
439 return width * height * 3 / 2;
444 /** Get the image associated to the frame.
446 * You should express the desired format, width, and height as inputs. As long
447 * as the loader producer was used to generate this or the imageconvert filter
448 * was attached, then you will get the image back in the format you desire.
449 * However, you do not always get the width and height you request depending
450 * on properties and filters. You do not need to supply a pre-allocated
451 * buffer, but you should always supply the desired image format.
453 * \public \memberof mlt_frame_s
454 * \param self a frame
455 * \param[out] buffer an image buffer
456 * \param[in,out] format the image format
457 * \param[in,out] width the horizontal size in pixels
458 * \param[in,out] height the vertical size in pixels
459 * \param writable whether or not you will need to be able to write to the memory returned in \p buffer
460 * \return true if error
461 * \todo Better describe the width and height as inputs.
464 int mlt_frame_get_image( mlt_frame self, uint8_t **buffer, mlt_image_format *format, int *width, int *height, int writable )
466 mlt_properties properties = MLT_FRAME_PROPERTIES( self );
467 mlt_get_image get_image = mlt_frame_pop_get_image( self );
468 mlt_producer producer = mlt_properties_get_data( properties, "test_card_producer", NULL );
469 mlt_image_format requested_format = *format;
474 mlt_properties_set_int( properties, "image_count", mlt_properties_get_int( properties, "image_count" ) - 1 );
475 error = get_image( self, buffer, format, width, height, writable );
476 if ( !error && *buffer )
478 mlt_properties_set_int( properties, "width", *width );
479 mlt_properties_set_int( properties, "height", *height );
480 if ( self->convert_image && *buffer && requested_format != mlt_image_none )
481 self->convert_image( self, buffer, format, requested_format );
482 mlt_properties_set_int( properties, "format", *format );
486 // Cause the image to be loaded from test card or fallback (white) below.
487 mlt_frame_get_image( self, buffer, format, width, height, writable );
490 else if ( mlt_properties_get_data( properties, "image", NULL ) )
492 *format = mlt_properties_get_int( properties, "format" );
493 *buffer = mlt_properties_get_data( properties, "image", NULL );
494 *width = mlt_properties_get_int( properties, "width" );
495 *height = mlt_properties_get_int( properties, "height" );
496 if ( self->convert_image && *buffer && requested_format != mlt_image_none )
498 self->convert_image( self, buffer, format, requested_format );
499 mlt_properties_set_int( properties, "format", *format );
504 mlt_frame test_frame = NULL;
505 mlt_service_get_frame( MLT_PRODUCER_SERVICE( producer ), &test_frame, 0 );
508 mlt_properties test_properties = MLT_FRAME_PROPERTIES( test_frame );
509 mlt_properties_set( test_properties, "rescale.interp", mlt_properties_get( properties, "rescale.interp" ) );
510 mlt_frame_get_image( test_frame, buffer, format, width, height, writable );
511 mlt_properties_set_data( properties, "test_card_frame", test_frame, 0, ( mlt_destructor )mlt_frame_close, NULL );
512 mlt_properties_set_double( properties, "aspect_ratio", mlt_frame_get_aspect_ratio( test_frame ) );
513 // mlt_properties_set_data( properties, "image", *buffer, *width * *height * 2, NULL, NULL );
514 // mlt_properties_set_int( properties, "width", *width );
515 // mlt_properties_set_int( properties, "height", *height );
516 // mlt_properties_set_int( properties, "format", *format );
520 mlt_properties_set_data( properties, "test_card_producer", NULL, 0, NULL, NULL );
521 mlt_frame_get_image( self, buffer, format, width, height, writable );
530 *width = *width == 0 ? 720 : *width;
531 *height = *height == 0 ? 576 : *height;
532 size = *width * *height;
534 mlt_properties_set_int( properties, "format", *format );
535 mlt_properties_set_int( properties, "width", *width );
536 mlt_properties_set_int( properties, "height", *height );
537 mlt_properties_set_int( properties, "aspect_ratio", 0 );
545 case mlt_image_rgb24:
548 *buffer = mlt_pool_alloc( size );
550 memset( *buffer, 255, size );
552 case mlt_image_rgb24a:
553 case mlt_image_opengl:
556 *buffer = mlt_pool_alloc( size );
558 memset( *buffer, 255, size );
560 case mlt_image_yuv422:
563 *buffer = mlt_pool_alloc( size );
566 while ( p != NULL && p != q )
572 case mlt_image_yuv420p:
574 *buffer = mlt_pool_alloc( size );
576 memset( *buffer, 255, size );
580 mlt_properties_set_data( properties, "image", *buffer, size, ( mlt_destructor )mlt_pool_release, NULL );
581 mlt_properties_set_int( properties, "test_image", 1 );
587 /** Get the alpha channel associated to the frame.
589 * \public \memberof mlt_frame_s
590 * \param self a frame
591 * \return the alpha channel
594 uint8_t *mlt_frame_get_alpha_mask( mlt_frame self )
596 uint8_t *alpha = NULL;
599 if ( self->get_alpha_mask != NULL )
600 alpha = self->get_alpha_mask( self );
602 alpha = mlt_properties_get_data( &self->parent, "alpha", NULL );
605 int size = mlt_properties_get_int( &self->parent, "width" ) * mlt_properties_get_int( &self->parent, "height" );
606 alpha = mlt_pool_alloc( size );
607 memset( alpha, 255, size );
608 mlt_properties_set_data( &self->parent, "alpha", alpha, size, mlt_pool_release, NULL );
614 /** Get the short name for an audio format.
616 * You do not need to deallocate the returned string.
617 * \public \memberof mlt_frame_s
618 * \param format an audio format enum
619 * \return a string for the name of the image format
622 const char * mlt_audio_format_name( mlt_audio_format format )
626 case mlt_audio_none: return "none";
627 case mlt_audio_s16: return "s16";
628 case mlt_audio_s32: return "s32";
629 case mlt_audio_s32le: return "s32le";
630 case mlt_audio_float: return "float";
631 case mlt_audio_f32le: return "f32le";
636 /** Get the amount of bytes needed for a block of audio.
638 * \public \memberof mlt_frame_s
639 * \param format an audio format enum
640 * \param samples the number of samples per channel
641 * \param channels the number of channels
642 * \return the number of bytes
645 int mlt_audio_format_size( mlt_audio_format format, int samples, int channels )
649 case mlt_audio_none: return 0;
650 case mlt_audio_s16: return samples * channels * sizeof( int16_t );
651 case mlt_audio_s32le:
652 case mlt_audio_s32: return samples * channels * sizeof( int32_t );
653 case mlt_audio_f32le:
654 case mlt_audio_float: return samples * channels * sizeof( float );
659 /** Get the audio associated to the frame.
661 * You should express the desired format, frequency, channels, and samples as inputs. As long
662 * as the loader producer was used to generate this or the audioconvert filter
663 * was attached, then you will get the audio back in the format you desire.
664 * However, you do not always get the channels and samples you request depending
665 * on properties and filters. You do not need to supply a pre-allocated
666 * buffer, but you should always supply the desired audio format.
667 * The audio is always in interleaved format.
668 * You should use the \p mlt_sample_calculator to determine the number of samples you want.
670 * \public \memberof mlt_frame_s
671 * \param self a frame
672 * \param[out] buffer an audio buffer
673 * \param[in,out] format the audio format
674 * \param[in,out] frequency the sample rate
675 * \param[in,out] channels
676 * \param[in,out] samples the number of samples per frame
677 * \return true if error
680 int mlt_frame_get_audio( mlt_frame self, void **buffer, mlt_audio_format *format, int *frequency, int *channels, int *samples )
682 mlt_get_audio get_audio = mlt_frame_pop_audio( self );
683 mlt_properties properties = MLT_FRAME_PROPERTIES( self );
684 int hide = mlt_properties_get_int( properties, "test_audio" );
685 mlt_audio_format requested_format = *format;
687 if ( hide == 0 && get_audio != NULL )
689 get_audio( self, buffer, format, frequency, channels, samples );
690 mlt_properties_set_int( properties, "audio_frequency", *frequency );
691 mlt_properties_set_int( properties, "audio_channels", *channels );
692 mlt_properties_set_int( properties, "audio_samples", *samples );
693 mlt_properties_set_int( properties, "audio_format", *format );
694 if ( self->convert_audio && *buffer && requested_format != mlt_audio_none )
695 self->convert_audio( self, buffer, format, requested_format );
697 else if ( mlt_properties_get_data( properties, "audio", NULL ) )
699 *buffer = mlt_properties_get_data( properties, "audio", NULL );
700 *format = mlt_properties_get_int( properties, "audio_format" );
701 *frequency = mlt_properties_get_int( properties, "audio_frequency" );
702 *channels = mlt_properties_get_int( properties, "audio_channels" );
703 *samples = mlt_properties_get_int( properties, "audio_samples" );
704 if ( self->convert_audio && *buffer && requested_format != mlt_audio_none )
705 self->convert_audio( self, buffer, format, requested_format );
710 *samples = *samples <= 0 ? 1920 : *samples;
711 *channels = *channels <= 0 ? 2 : *channels;
712 *frequency = *frequency <= 0 ? 48000 : *frequency;
713 mlt_properties_set_int( properties, "audio_frequency", *frequency );
714 mlt_properties_set_int( properties, "audio_channels", *channels );
715 mlt_properties_set_int( properties, "audio_samples", *samples );
716 mlt_properties_set_int( properties, "audio_format", *format );
725 size = *samples * *channels * sizeof( int16_t );
728 size = *samples * *channels * sizeof( int32_t );
730 case mlt_audio_float:
731 size = *samples * *channels * sizeof( float );
737 *buffer = mlt_pool_alloc( size );
739 memset( *buffer, 0, size );
740 mlt_properties_set_data( properties, "audio", *buffer, size, ( mlt_destructor )mlt_pool_release, NULL );
741 mlt_properties_set_int( properties, "test_audio", 1 );
744 // TODO: This does not belong here
745 if ( *format == mlt_audio_s16 && mlt_properties_get( properties, "meta.volume" ) )
747 double value = mlt_properties_get_double( properties, "meta.volume" );
751 memset( *buffer, 0, *samples * *channels * 2 );
753 else if ( value != 1.0 )
755 int total = *samples * *channels;
756 int16_t *p = *buffer;
764 mlt_properties_set( properties, "meta.volume", NULL );
770 /** Set the audio on a frame.
772 * \public \memberof mlt_frame_s
773 * \param self a frame
774 * \param buffer an buffer containing audio samples
775 * \param format the format of the audio in the \p buffer
776 * \param size the total size of the buffer (optional)
777 * \param destructor a function that releases or deallocates the \p buffer
778 * \return true if error
781 int mlt_frame_set_audio( mlt_frame self, void *buffer, mlt_audio_format format, int size, mlt_destructor destructor )
783 mlt_properties_set_int( MLT_FRAME_PROPERTIES( self ), "audio_format", format );
784 return mlt_properties_set_data( MLT_FRAME_PROPERTIES( self ), "audio", buffer, size, destructor, NULL );
787 /** Get audio on a frame as a waveform image.
789 * This generates an 8-bit grayscale image representation of the audio in a
790 * frame. Currently, this only really works for 2 channels.
791 * This allocates the bitmap using mlt_pool so you should release the return
792 * value with \p mlt_pool_release.
794 * \public \memberof mlt_frame_s
795 * \param self a frame
796 * \param w the width of the image
797 * \param h the height of the image to create
798 * \return a pointer to a new bitmap
801 unsigned char *mlt_frame_get_waveform( mlt_frame self, int w, int h )
804 mlt_properties properties = MLT_FRAME_PROPERTIES( self );
805 mlt_audio_format format = mlt_audio_s16;
806 int frequency = 16000;
808 mlt_producer producer = mlt_frame_get_original_producer( self );
809 double fps = mlt_producer_get_fps( mlt_producer_cut_parent( producer ) );
810 int samples = mlt_sample_calculator( fps, frequency, mlt_frame_get_position( self ) );
812 // Increase audio resolution proportional to requested image size
813 while ( samples < w )
816 samples = mlt_sample_calculator( fps, frequency, mlt_frame_get_position( self ) );
820 mlt_frame_get_audio( self, (void**)&pcm, &format, &frequency, &channels, &samples );
822 // Make an 8-bit buffer large enough to hold rendering
824 unsigned char *bitmap = ( unsigned char* )mlt_pool_alloc( size );
825 if ( bitmap != NULL )
826 memset( bitmap, 0, size );
829 mlt_properties_set_data( properties, "waveform", bitmap, size, ( mlt_destructor )mlt_pool_release, NULL );
831 // Render vertical lines
832 int16_t *ubound = pcm + samples * channels;
833 int skip = samples / w;
834 skip = !skip ? 1 : skip;
835 unsigned char gray = 0xFF / skip;
838 // Iterate sample stream and along x coordinate
839 for ( i = 0; pcm < ubound; i++ )
841 // pcm data has channels interleaved
842 for ( j = 0; j < channels; j++, pcm++ )
844 // Determine sample's magnitude from 2s complement;
845 int pcm_magnitude = *pcm < 0 ? ~(*pcm) + 1 : *pcm;
846 // The height of a line is the ratio of the magnitude multiplied by
847 // the vertical resolution of a single channel
848 int height = h * pcm_magnitude / channels / 2 / 32768;
849 // Determine the starting y coordinate - left top, right bottom
850 int displacement = h * (j * 2 + 1) / channels / 2 - ( *pcm < 0 ? 0 : height );
851 // Position buffer pointer using y coordinate, stride, and x coordinate
852 unsigned char *p = bitmap + i / skip + displacement * w;
854 // Draw vertical line
855 for ( k = 0; k < height + 1; k++ )
857 p[ w * k ] = ( k == 0 ) ? 0xFF : p[ w * k ] + gray;
859 p[ w * k ] = ( k == height ) ? 0xFF : p[ w * k ] + gray;
866 /** Get the end service that produced self frame.
868 * This fetches the first producer of the frame and not any producers that
871 * \public \memberof mlt_frame_s
872 * \param self a frame
876 mlt_producer mlt_frame_get_original_producer( mlt_frame self )
879 return mlt_properties_get_data( MLT_FRAME_PROPERTIES( self ), "_producer", NULL );
883 /** Destroy the frame.
885 * \public \memberof mlt_frame_s
886 * \param self a frame
889 void mlt_frame_close( mlt_frame self )
891 if ( self != NULL && mlt_properties_dec_ref( MLT_FRAME_PROPERTIES( self ) ) <= 0 )
893 mlt_deque_close( self->stack_image );
894 mlt_deque_close( self->stack_audio );
895 while( mlt_deque_peek_back( self->stack_service ) )
896 mlt_service_close( mlt_deque_pop_back( self->stack_service ) );
897 mlt_deque_close( self->stack_service );
898 mlt_properties_close( &self->parent );
903 /***** convenience functions *****/
905 /** Determine the number of samples that belong in a frame at a time position.
907 * \public \memberof mlt_frame_s
908 * \param fps the frame rate
909 * \param frequency the sample rate
910 * \param position the time position
911 * \return the number of samples per channel
914 int mlt_sample_calculator( float fps, int frequency, int64_t position )
916 /* Compute the cumulative number of samples until the start of this frame and the
917 cumulative number of samples until the start of the next frame. Round each to the
918 nearest integer and take the difference to determine the number of samples in
921 This approach should prevent rounding errors that can accumulate over a large number
922 of frames causing A/V sync problems. */
923 return mlt_sample_calculator_to_now( fps, frequency, position + 1 )
924 - mlt_sample_calculator_to_now( fps, frequency, position );
927 /** Determine the number of samples that belong before a time position.
929 * \public \memberof mlt_frame_s
930 * \param fps the frame rate
931 * \param frequency the sample rate
932 * \param position the time position
933 * \return the number of samples per channel
934 * \bug Will this break when mlt_position is converted to double?
937 int64_t mlt_sample_calculator_to_now( float fps, int frequency, int64_t position )
943 samples = (int64_t)( (double) position * (double) frequency / (double) fps +
944 ( position < 0 ? -0.5 : 0.5 ) );
950 void mlt_frame_write_ppm( mlt_frame frame )
954 mlt_image_format format = mlt_image_rgb24;
957 if ( mlt_frame_get_image( frame, &image, &format, &width, &height, 0 ) == 0 )
962 sprintf( filename, "frame-%05d.ppm", mlt_frame_get_position( frame ) );
963 file = fopen( filename, "wb" );
966 fprintf( file, "P6\n%d %d\n255\n", width, height);
967 fwrite( image, width * height * 3, 1, file );
972 /** Get or create a properties object unique to this service instance.
974 * Use this function to hold a service's processing parameters for this
975 * particular frame. Set the parameters in the service's process function.
976 * Then, get the parameters in the function it pushes to the frame's audio
977 * or image stack. This makes the service more parallel by reducing race
978 * conditions and less sensitive to multiple instances (by not setting a
979 * non-unique property on the frame). Creation and destruction of the
980 * properties object is handled automatically.
982 * \public \memberof mlt_frame_s
983 * \param self a frame
984 * \param service a service
985 * \return a properties object
988 mlt_properties mlt_frame_unique_properties( mlt_frame self, mlt_service service )
990 mlt_properties frame_props = MLT_FRAME_PROPERTIES( self );
991 mlt_properties service_props = MLT_SERVICE_PROPERTIES( service );
992 char *unique = mlt_properties_get( service_props, "_unique_id" );
993 mlt_properties instance_props = mlt_properties_get_data( frame_props, unique, NULL );
995 if ( !instance_props )
997 instance_props = mlt_properties_new();
998 mlt_properties_set_data( frame_props, unique, instance_props, 0, (mlt_destructor) mlt_properties_close, NULL );
1001 return instance_props;
1004 /** Make a copy of a frame.
1006 * This does not copy the get_image/get_audio processing stacks or any
1007 * data properties other than the audio and image.
1009 * \public \memberof mlt_frame_s
1010 * \param self the frame to clone
1011 * \param is_deep a boolean to indicate whether to make a deep copy of the audio
1012 * and video data chunks or to make a shallow copy by pointing to the supplied frame
1013 * \return a almost-complete copy of the frame
1014 * \todo copy the processing deques
1017 mlt_frame mlt_frame_clone( mlt_frame self, int is_deep )
1019 mlt_frame new_frame = mlt_frame_init( NULL );
1020 mlt_properties properties = MLT_FRAME_PROPERTIES( self );
1021 mlt_properties new_props = MLT_FRAME_PROPERTIES( new_frame );
1025 mlt_properties_inherit( new_props, properties );
1028 data = mlt_properties_get_data( properties, "audio", &size );
1032 size = mlt_audio_format_size( mlt_properties_get_int( properties, "audio_format" ),
1033 mlt_properties_get_int( properties, "audio_samples" ),
1034 mlt_properties_get_int( properties, "audio_channels" ) );
1035 copy = mlt_pool_alloc( size );
1036 memcpy( copy, data, size );
1037 mlt_properties_set_data( new_props, "audio", copy, size, mlt_pool_release, NULL );
1039 data = mlt_properties_get_data( properties, "image", &size );
1043 size = mlt_image_format_size( mlt_properties_get_int( properties, "format" ),
1044 mlt_properties_get_int( properties, "width" ),
1045 mlt_properties_get_int( properties, "height" ), NULL );
1046 copy = mlt_pool_alloc( size );
1047 memcpy( copy, data, size );
1048 mlt_properties_set_data( new_props, "image", copy, size, mlt_pool_release, NULL );
1050 data = mlt_properties_get_data( properties, "alpha", &size );
1054 size = mlt_properties_get_int( properties, "width" ) *
1055 mlt_properties_get_int( properties, "height" );
1056 copy = mlt_pool_alloc( size );
1057 memcpy( copy, data, size );
1058 mlt_properties_set_data( new_props, "alpha", copy, size, mlt_pool_release, NULL );
1064 // This frame takes a reference on the original frame since the data is a shallow copy.
1065 mlt_properties_inc_ref( properties );
1066 mlt_properties_set_data( new_props, "_cloned_frame", self, 0,
1067 (mlt_destructor) mlt_frame_close, NULL );
1070 data = mlt_properties_get_data( properties, "audio", &size );
1071 mlt_properties_set_data( new_props, "audio", data, size, NULL, NULL );
1072 data = mlt_properties_get_data( properties, "image", &size );
1073 mlt_properties_set_data( new_props, "image", data, size, NULL, NULL );
1074 data = mlt_properties_get_data( properties, "alpha", &size );
1075 mlt_properties_set_data( new_props, "alpha", data, size, NULL, NULL );