Service Documentation
-Copyright (C) 2004 Ushodaya Enterprises Limited
Authors: Charles Yates <charles.yates@pandora.be>
Dan Dennedy <dan@dennedy.org>
-Last Revision: 2004-03-20
+Last Revision: $Date$
SERVICES
--------
- Services marked as "(Proprietary)" are not distributed with the GPL version
- of mlt.
+ Services marked as "(Proprietary)" are not distributed with the LGPL
+ version of mlt.
Producers
---------
Read Only Properties
string resource - file location
- double fps - this is fixed at 25 for PAL currently
double source_fps - the framerate of the resource
double aspect_ratio - sample aspect ratio of the resource
- this is determined on every frame read
Dependencies
- ffmpeg must be configured as --enable-shared and installed prior
- to compilation of mlt.
+ ffmpeg
Known Bugs
Audio sync discrepancy with some content.
Not all libavformat supported formats are seekable.
- Ogg Vorbis is currently broken.
- MPEG seeking is inaccurate - doesn't seek to i-frames so you may
- get junk for a few frames.
- RAW DV seeking not supported.
Fails to play beyond first frame of video of sources with PTS not
starting at 0 (video4linux).
default "Sans 48". FreeType2 renders at 72 dpi.
string encoding - the text encoding type of the input if not UTF-8.
- see 'iconv --list' for a list of possible inputs.
+ int weight - the weight of the font (default is 400)
Read Only Properties
int in - in point
int out - out point
+ int begin - when using an image sequence, this sets the starting
+ number.
Mutable Properties
none
+ jackrack
+
+ Description
+
+ Creates Jack ports and runs a JackRack project to process audio
+ through a stack of LADSPA filters.
+
+ Constructor Argument
+
+ src - a JackRack file
+
+ Details
+
+ If you are using a consumer that uses ALSA, then you should start
+ jackd with the dummy driver: jackd -d dummy.
+ I also recommend using a period size of 2048: -p 2048.
+
+ jackd -ddummy -r48000 -p2048
+
+ Initialisation Properties
+
+ int in - in point
+ int out - out point
+
+ The following can be used without a rack file in order to connect
+ filter_jackrack to a running instance of JackRack:
+ string out_1 - Jack port to connect MLT's output port (JackRack's input)
+ string out_2 - Jack port to connect MLT's output port (JackRack's input)
+ string in_1 - Jack port to connect MLT's input port (JackRack's output)
+ string in_2 - Jack port to connect MLT's input port (JackRack's output)
+
+ Read Only Properties
+
+ none
+
+ Mutable Properties
+
+ none
+
+ Dependencies
+
+ Jack, LADSPA, glib-2.0, libxml2
+
+ Known Bugs
+
+ Currently, due to timing and synchronisation issues, the audio
+ is distorted with repeated samples and latency clicks.
+ no encapsulated resampling and jack runs at a fixed frequency
+
+ ladspa
+
+ Description
+
+ Runs a JackRack project to process audio through a stack of
+ LADSPA filters without using Jack.
+
+ Constructor Argument
+
+ src - a JackRack file
+
+ Details
+
+ Due to audio integrity issues with the jackrack filter, this
+ filter is better for runtime, while jackrack is more suitable
+ for prototyping a rack file using the Jack Rack GUI.
+
+ Initialisation Properties
+
+ int in - in point
+ int out - out point
+
+ Read Only Properties
+
+ none
+
+ Mutable Properties
+
+ none
+
+ Dependencies
+
+ Jack, LADSPA, glib-2.0, libxml2
+ Jack is still required because this coexists with the jackrack
+ filter.
+
+ Known Bugs
+
+ no encapsulated resampling and jack runs at a fixed frequency
+
luma
Description
none
+ mono
+
+ Description
+
+ Mix all channels of audio into a mono signal and output it as
+ N channels.
+
+ Constructor Argument
+
+ channels - the number of output channels (default 2)
+
+ Initialisation Properties
+
+ none
+
+ Read Only Properties
+
+ none
+
+ Mutable Properties
+
+ none
+
+ Dependencies
+
+ none
+
+ Known Bugs
+
+ none
+
+
obscure
Description
double volume - audio level factor
int video_off - if 1, disable video output
int audio_off - if 1, disable audio output
- int scale_overlay - if 1, resample video from source pixel aspect
- ratio to square pixels.
+ int resize - TODO
int progressive - indicates whether to use progressive or field-
based rendering, default 0 (off).
int audio_buffer - size of the sdl audio buffer (default: 1024)