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";
632 case mlt_audio_u8: return "u8";
637 /** Get the amount of bytes needed for a block of audio.
639 * \public \memberof mlt_frame_s
640 * \param format an audio format enum
641 * \param samples the number of samples per channel
642 * \param channels the number of channels
643 * \return the number of bytes
646 int mlt_audio_format_size( mlt_audio_format format, int samples, int channels )
650 case mlt_audio_none: return 0;
651 case mlt_audio_s16: return samples * channels * sizeof( int16_t );
652 case mlt_audio_s32le:
653 case mlt_audio_s32: return samples * channels * sizeof( int32_t );
654 case mlt_audio_f32le:
655 case mlt_audio_float: return samples * channels * sizeof( float );
656 case mlt_audio_u8: return samples * channels;
661 /** Get the audio associated to the frame.
663 * You should express the desired format, frequency, channels, and samples as inputs. As long
664 * as the loader producer was used to generate this or the audioconvert filter
665 * was attached, then you will get the audio back in the format you desire.
666 * However, you do not always get the channels and samples you request depending
667 * on properties and filters. You do not need to supply a pre-allocated
668 * buffer, but you should always supply the desired audio format.
669 * The audio is always in interleaved format.
670 * You should use the \p mlt_sample_calculator to determine the number of samples you want.
672 * \public \memberof mlt_frame_s
673 * \param self a frame
674 * \param[out] buffer an audio buffer
675 * \param[in,out] format the audio format
676 * \param[in,out] frequency the sample rate
677 * \param[in,out] channels
678 * \param[in,out] samples the number of samples per frame
679 * \return true if error
682 int mlt_frame_get_audio( mlt_frame self, void **buffer, mlt_audio_format *format, int *frequency, int *channels, int *samples )
684 mlt_get_audio get_audio = mlt_frame_pop_audio( self );
685 mlt_properties properties = MLT_FRAME_PROPERTIES( self );
686 int hide = mlt_properties_get_int( properties, "test_audio" );
687 mlt_audio_format requested_format = *format;
689 if ( hide == 0 && get_audio != NULL )
691 get_audio( self, buffer, format, frequency, channels, samples );
692 mlt_properties_set_int( properties, "audio_frequency", *frequency );
693 mlt_properties_set_int( properties, "audio_channels", *channels );
694 mlt_properties_set_int( properties, "audio_samples", *samples );
695 mlt_properties_set_int( properties, "audio_format", *format );
696 if ( self->convert_audio && *buffer && requested_format != mlt_audio_none )
697 self->convert_audio( self, buffer, format, requested_format );
699 else if ( mlt_properties_get_data( properties, "audio", NULL ) )
701 *buffer = mlt_properties_get_data( properties, "audio", NULL );
702 *format = mlt_properties_get_int( properties, "audio_format" );
703 *frequency = mlt_properties_get_int( properties, "audio_frequency" );
704 *channels = mlt_properties_get_int( properties, "audio_channels" );
705 *samples = mlt_properties_get_int( properties, "audio_samples" );
706 if ( self->convert_audio && *buffer && requested_format != mlt_audio_none )
707 self->convert_audio( self, buffer, format, requested_format );
712 *samples = *samples <= 0 ? 1920 : *samples;
713 *channels = *channels <= 0 ? 2 : *channels;
714 *frequency = *frequency <= 0 ? 48000 : *frequency;
715 mlt_properties_set_int( properties, "audio_frequency", *frequency );
716 mlt_properties_set_int( properties, "audio_channels", *channels );
717 mlt_properties_set_int( properties, "audio_samples", *samples );
718 mlt_properties_set_int( properties, "audio_format", *format );
727 size = *samples * *channels * sizeof( int16_t );
730 size = *samples * *channels * sizeof( int32_t );
732 case mlt_audio_float:
733 size = *samples * *channels * sizeof( float );
739 *buffer = mlt_pool_alloc( size );
741 memset( *buffer, 0, size );
742 mlt_properties_set_data( properties, "audio", *buffer, size, ( mlt_destructor )mlt_pool_release, NULL );
743 mlt_properties_set_int( properties, "test_audio", 1 );
746 // TODO: This does not belong here
747 if ( *format == mlt_audio_s16 && mlt_properties_get( properties, "meta.volume" ) )
749 double value = mlt_properties_get_double( properties, "meta.volume" );
753 memset( *buffer, 0, *samples * *channels * 2 );
755 else if ( value != 1.0 )
757 int total = *samples * *channels;
758 int16_t *p = *buffer;
766 mlt_properties_set( properties, "meta.volume", NULL );
772 /** Set the audio on a frame.
774 * \public \memberof mlt_frame_s
775 * \param self a frame
776 * \param buffer an buffer containing audio samples
777 * \param format the format of the audio in the \p buffer
778 * \param size the total size of the buffer (optional)
779 * \param destructor a function that releases or deallocates the \p buffer
780 * \return true if error
783 int mlt_frame_set_audio( mlt_frame self, void *buffer, mlt_audio_format format, int size, mlt_destructor destructor )
785 mlt_properties_set_int( MLT_FRAME_PROPERTIES( self ), "audio_format", format );
786 return mlt_properties_set_data( MLT_FRAME_PROPERTIES( self ), "audio", buffer, size, destructor, NULL );
789 /** Get audio on a frame as a waveform image.
791 * This generates an 8-bit grayscale image representation of the audio in a
792 * frame. Currently, this only really works for 2 channels.
793 * This allocates the bitmap using mlt_pool so you should release the return
794 * value with \p mlt_pool_release.
796 * \public \memberof mlt_frame_s
797 * \param self a frame
798 * \param w the width of the image
799 * \param h the height of the image to create
800 * \return a pointer to a new bitmap
803 unsigned char *mlt_frame_get_waveform( mlt_frame self, int w, int h )
806 mlt_properties properties = MLT_FRAME_PROPERTIES( self );
807 mlt_audio_format format = mlt_audio_s16;
808 int frequency = 16000;
810 mlt_producer producer = mlt_frame_get_original_producer( self );
811 double fps = mlt_producer_get_fps( mlt_producer_cut_parent( producer ) );
812 int samples = mlt_sample_calculator( fps, frequency, mlt_frame_get_position( self ) );
814 // Increase audio resolution proportional to requested image size
815 while ( samples < w )
818 samples = mlt_sample_calculator( fps, frequency, mlt_frame_get_position( self ) );
822 mlt_frame_get_audio( self, (void**)&pcm, &format, &frequency, &channels, &samples );
824 // Make an 8-bit buffer large enough to hold rendering
828 unsigned char *bitmap = ( unsigned char* )mlt_pool_alloc( size );
829 if ( bitmap != NULL )
830 memset( bitmap, 0, size );
833 mlt_properties_set_data( properties, "waveform", bitmap, size, ( mlt_destructor )mlt_pool_release, NULL );
835 // Render vertical lines
836 int16_t *ubound = pcm + samples * channels;
837 int skip = samples / w;
838 skip = !skip ? 1 : skip;
839 unsigned char gray = 0xFF / skip;
842 // Iterate sample stream and along x coordinate
843 for ( i = 0; pcm < ubound; i++ )
845 // pcm data has channels interleaved
846 for ( j = 0; j < channels; j++, pcm++ )
848 // Determine sample's magnitude from 2s complement;
849 int pcm_magnitude = *pcm < 0 ? ~(*pcm) + 1 : *pcm;
850 // The height of a line is the ratio of the magnitude multiplied by
851 // the vertical resolution of a single channel
852 int height = h * pcm_magnitude / channels / 2 / 32768;
853 // Determine the starting y coordinate - left top, right bottom
854 int displacement = h * (j * 2 + 1) / channels / 2 - ( *pcm < 0 ? 0 : height );
855 // Position buffer pointer using y coordinate, stride, and x coordinate
856 unsigned char *p = bitmap + i / skip + displacement * w;
858 // Draw vertical line
859 for ( k = 0; k < height + 1; k++ )
861 p[ w * k ] = ( k == 0 ) ? 0xFF : p[ w * k ] + gray;
863 p[ w * k ] = ( k == height ) ? 0xFF : p[ w * k ] + gray;
870 /** Get the end service that produced self frame.
872 * This fetches the first producer of the frame and not any producers that
875 * \public \memberof mlt_frame_s
876 * \param self a frame
880 mlt_producer mlt_frame_get_original_producer( mlt_frame self )
883 return mlt_properties_get_data( MLT_FRAME_PROPERTIES( self ), "_producer", NULL );
887 /** Destroy the frame.
889 * \public \memberof mlt_frame_s
890 * \param self a frame
893 void mlt_frame_close( mlt_frame self )
895 if ( self != NULL && mlt_properties_dec_ref( MLT_FRAME_PROPERTIES( self ) ) <= 0 )
897 mlt_deque_close( self->stack_image );
898 mlt_deque_close( self->stack_audio );
899 while( mlt_deque_peek_back( self->stack_service ) )
900 mlt_service_close( mlt_deque_pop_back( self->stack_service ) );
901 mlt_deque_close( self->stack_service );
902 mlt_properties_close( &self->parent );
907 /***** convenience functions *****/
909 /** Determine the number of samples that belong in a frame at a time position.
911 * \public \memberof mlt_frame_s
912 * \param fps the frame rate
913 * \param frequency the sample rate
914 * \param position the time position
915 * \return the number of samples per channel
918 int mlt_sample_calculator( float fps, int frequency, int64_t position )
920 /* Compute the cumulative number of samples until the start of this frame and the
921 cumulative number of samples until the start of the next frame. Round each to the
922 nearest integer and take the difference to determine the number of samples in
925 This approach should prevent rounding errors that can accumulate over a large number
926 of frames causing A/V sync problems. */
927 return mlt_sample_calculator_to_now( fps, frequency, position + 1 )
928 - mlt_sample_calculator_to_now( fps, frequency, position );
931 /** Determine the number of samples that belong before a time position.
933 * \public \memberof mlt_frame_s
934 * \param fps the frame rate
935 * \param frequency the sample rate
936 * \param position the time position
937 * \return the number of samples per channel
938 * \bug Will this break when mlt_position is converted to double?
941 int64_t mlt_sample_calculator_to_now( float fps, int frequency, int64_t position )
947 samples = (int64_t)( (double) position * (double) frequency / (double) fps +
948 ( position < 0 ? -0.5 : 0.5 ) );
954 void mlt_frame_write_ppm( mlt_frame frame )
958 mlt_image_format format = mlt_image_rgb24;
961 if ( mlt_frame_get_image( frame, &image, &format, &width, &height, 0 ) == 0 )
966 sprintf( filename, "frame-%05d.ppm", mlt_frame_get_position( frame ) );
967 file = fopen( filename, "wb" );
970 fprintf( file, "P6\n%d %d\n255\n", width, height);
971 fwrite( image, width * height * 3, 1, file );
976 /** Get or create a properties object unique to this service instance.
978 * Use this function to hold a service's processing parameters for this
979 * particular frame. Set the parameters in the service's process function.
980 * Then, get the parameters in the function it pushes to the frame's audio
981 * or image stack. This makes the service more parallel by reducing race
982 * conditions and less sensitive to multiple instances (by not setting a
983 * non-unique property on the frame). Creation and destruction of the
984 * properties object is handled automatically.
986 * \public \memberof mlt_frame_s
987 * \param self a frame
988 * \param service a service
989 * \return a properties object
992 mlt_properties mlt_frame_unique_properties( mlt_frame self, mlt_service service )
994 mlt_properties frame_props = MLT_FRAME_PROPERTIES( self );
995 mlt_properties service_props = MLT_SERVICE_PROPERTIES( service );
996 char *unique = mlt_properties_get( service_props, "_unique_id" );
997 mlt_properties instance_props = mlt_properties_get_data( frame_props, unique, NULL );
999 if ( !instance_props )
1001 instance_props = mlt_properties_new();
1002 mlt_properties_set_data( frame_props, unique, instance_props, 0, (mlt_destructor) mlt_properties_close, NULL );
1005 return instance_props;
1008 /** Make a copy of a frame.
1010 * This does not copy the get_image/get_audio processing stacks or any
1011 * data properties other than the audio and image.
1013 * \public \memberof mlt_frame_s
1014 * \param self the frame to clone
1015 * \param is_deep a boolean to indicate whether to make a deep copy of the audio
1016 * and video data chunks or to make a shallow copy by pointing to the supplied frame
1017 * \return a almost-complete copy of the frame
1018 * \todo copy the processing deques
1021 mlt_frame mlt_frame_clone( mlt_frame self, int is_deep )
1023 mlt_frame new_frame = mlt_frame_init( NULL );
1024 mlt_properties properties = MLT_FRAME_PROPERTIES( self );
1025 mlt_properties new_props = MLT_FRAME_PROPERTIES( new_frame );
1029 mlt_properties_inherit( new_props, properties );
1032 data = mlt_properties_get_data( properties, "audio", &size );
1036 size = mlt_audio_format_size( mlt_properties_get_int( properties, "audio_format" ),
1037 mlt_properties_get_int( properties, "audio_samples" ),
1038 mlt_properties_get_int( properties, "audio_channels" ) );
1039 copy = mlt_pool_alloc( size );
1040 memcpy( copy, data, size );
1041 mlt_properties_set_data( new_props, "audio", copy, size, mlt_pool_release, NULL );
1043 data = mlt_properties_get_data( properties, "image", &size );
1047 size = mlt_image_format_size( mlt_properties_get_int( properties, "format" ),
1048 mlt_properties_get_int( properties, "width" ),
1049 mlt_properties_get_int( properties, "height" ), NULL );
1050 copy = mlt_pool_alloc( size );
1051 memcpy( copy, data, size );
1052 mlt_properties_set_data( new_props, "image", copy, size, mlt_pool_release, NULL );
1054 data = mlt_properties_get_data( properties, "alpha", &size );
1058 size = mlt_properties_get_int( properties, "width" ) *
1059 mlt_properties_get_int( properties, "height" );
1060 copy = mlt_pool_alloc( size );
1061 memcpy( copy, data, size );
1062 mlt_properties_set_data( new_props, "alpha", copy, size, mlt_pool_release, NULL );
1068 // This frame takes a reference on the original frame since the data is a shallow copy.
1069 mlt_properties_inc_ref( properties );
1070 mlt_properties_set_data( new_props, "_cloned_frame", self, 0,
1071 (mlt_destructor) mlt_frame_close, NULL );
1074 data = mlt_properties_get_data( properties, "audio", &size );
1075 mlt_properties_set_data( new_props, "audio", data, size, NULL, NULL );
1076 data = mlt_properties_get_data( properties, "image", &size );
1077 mlt_properties_set_data( new_props, "image", data, size, NULL, NULL );
1078 data = mlt_properties_get_data( properties, "alpha", &size );
1079 mlt_properties_set_data( new_props, "alpha", data, size, NULL, NULL );