MLT  7.28.0
Properties Dictionary
Class mlt_consumer_s

rescale the scaling algorithm to pass on to all scaling filters, defaults to "bilinear"

buffer the number of frames to use in the asynchronous render thread, defaults to 25

prefill the number of frames to render before commencing output when real_time <> 0, defaults to the size of buffer

drop_max the maximum number of consecutively dropped frames, defaults to 5

frequency the audio sample rate to use in Hertz, defaults to 48000

channels the number of audio channels to use, defaults to 2

channel_layout the layout of the audio channels, defaults to auto. other options include: mono, stereo, 5.1, 7.1, etc.

real_time the asynchronous behavior: 1 (default) for asynchronous with frame dropping, -1 for asynchronous without frame dropping, 0 to disable (synchronous)

test_card the name of a resource to use as the test card, defaults to environment variable MLT_TEST_CARD. If undefined, the hard-coded default test card is white silence. A test card is what appears when nothing is produced.

fps video frames per second as floating point (read only)

frame_rate_num the numerator of the video frame rate, overrides mlt_profile_s

frame_rate_den the denominator of the video frame rate, overrides mlt_profile_s

width the horizontal video resolution, overrides mlt_profile_s

height the vertical video resolution, overrides mlt_profile_s

progressive a flag that indicates if the video is interlaced or progressive, overrides mlt_profile_s

aspect_ratio the video sample (pixel) aspect ratio as floating point (read only)

sample_aspect_num the numerator of the sample aspect ratio, overrides mlt_profile_s

sample_aspect_den the denominator of the sample aspect ratio, overrides mlt_profile_s

display_ratio the video frame aspect ratio as floating point (read only)

display_aspect_num the numerator of the video frame aspect ratio, overrides mlt_profile_s

display_aspect_den the denominator of the video frame aspect ratio, overrides mlt_profile_s

priority the OS scheduling priority for the render threads when real_time is not 0.

top_field_first when not progressive, whether interlace field order is top-field-first, defaults to 0. Set this to -1 if the consumer does not care about the field order.

mlt_image_format the image format to request in rendering threads, defaults to yuv422

mlt_audio_format the audio format to request in rendering threads, defaults to S16

audio_off set non-zero to disable audio processing

video_off set non-zero to disable video processing

drop_count the number of video frames not rendered since starting consumer

color_range the color range as tv/mpeg (limited) or pc/jpeg (full); default is unset, which implies tv/mpeg

color_trc the color transfer characteristic (gamma), default is unset

deinterlacer the deinterlace algorithm to pass to deinterlace filters, defaults to "yadif"

Class mlt_filter_s

track the index of the track of a multitrack on which the filter is applied

service a reference to the service to which this filter is attached.

disable Set this to disable the filter while keeping it in the object model. Currently this is not cleared when the filter is detached.

Class mlt_frame_s

test_image set if the frame holds a "test card" image

test_audio set if the frame holds "test card" audio

_producer holds a reference to the frame's end producer

_speed the current speed of the producer that generated the frame

_position the position of the frame

meta.* holds metadata

hide set to 1 to hide the video, 2 to mute the audio

last_track a flag to indicate an end-of-tracks frame

previous frame a reference to the unfiltered preceding frame (no speed factor applied, only available when _need_previous_next is set on the producer)

next frame a reference to the unfiltered following frame (no speed factor applied, only available when _need_previous_next is set on the producer)

colorspace the standard for the YUV coefficients

force_full_luma luma range handling: 1 for full range, 0 for scaling (DEPRECATED)

color_trc the color transfer characteristic (gamma)

audio_frequency the sample rate of the audio

audio_channels the number of audio channels

audio_samples the number of audio samples

audio_format the mlt_audio_format for the audio on this frame

format the mlt_image_format of the image on this frame

width the horizontal resolution of the image

height the vertical resolution of the image

aspect_ratio the sample aspect ratio of the image

full_range set if the video is full range - only applies to Y'CbCr

meta.playlist.clip_position mlt_playlist sets this property to the time position of this frame's clip in the playlist

meta.playlist.clip_length mlt_playlist sets this property to the playlist index of this frame's clip in the playlist

Class mlt_link_s
next holds a reference to the next producer in the chain
Class mlt_multitrack_s
log_id not currently used, but sets it to "mulitrack"
Class mlt_playlist_s

autoclose Set this true if you are doing sequential processing and want to automatically close producers as they are finished being used to free resources.

meta.fx_cut Set true on a producer to indicate that it is a "fx_cut," which is a way to add filters as a playlist entry - useful only in a multitrack. See FxCut in the docs.

mix_in

mix_out

hide Set to 1 to hide the video (make it an audio-only track), 2 to hide the audio (make it a video-only track), or 3 to hide audio and video (hidden track). This property only applies when using a multitrack or transition.

Class mlt_producer_s

mlt_type the name of the service subclass, e.g. mlt_producer

mlt_service the name of a producer subclass

_position the current position of the play head, relative to the in point

_frame the current position of the play head, relative to the beginning of the resource

_speed the current speed factor, where 1.0 is normal

aspect_ratio sample aspect ratio

length the duration of the cut in frames

eof the end-of-file behavior, one of: pause, continue, loop

resource the file name, stream address, or the class name in angle brackets

_cut set if this producer is a "cut" producer

mlt_mix stores the data for a "mix" producer

_cut_parent holds a reference to the cut's parent producer

ignore_points Set this to temporarily disable the in and out points.

use_clone holds a reference to a clone's producer, as created by mlt_producer_optimise

_clone is the index of the clone in the list of clones stored on the clone's producer

_clones is the number of clones of the producer, as created by mlt_producer_optimise

_clone.{N} holds a reference to the N'th clone of the producer, as created by mlt_producer_optimise

meta.* holds metadata - there is a loose taxonomy to be defined

set.* holds properties to set on a frame produced

Class mlt_repository_s
language a cached list of user locales
Class mlt_service_s

mlt_type identifies the subclass

_mlt_service_hidden a flag that indicates whether to hide the mlt_service

mlt_service is the name of the implementation of the service

resource is either the stream identifier or grandchild-class

in when to start, what is started is service-specific

out when to stop

_filter_private Set this on a service to ensure that attached filters are handled privately. See modules/core/filter_watermark.c for example.

_profile stores the mlt_profile for a service

_unique_id is a unique identifier

_need_previous_next boolean that instructs producers to get preceding and following frames inside of mlt_service_get_frame

Class mlt_tractor_s

multitrack holds a reference to the mulitrack object that a tractor manages

field holds a reference to the field object that a tractor manages

producer holds a reference to an encapsulated producer

Class mlt_transition_s

a_track the track index (0-based) of a multitrack of the first producer

b_track the track index (0-based) of a multitrack of the second producer

accepts_blanks a flag to indicate if the transition should accept blank frames

always_active a flag to indicate that the in and out points do not apply

_transition_type 1 for video, 2 for audio, 3 for both audio and video

disable Set this to disable the transition while keeping it in the object model.