3 Copyright (C) 2004-2005 Ushodaya Enterprises Limited
4 Authors: Charles Yates <charles.yates@pandora.be>
5 Dan Dennedy <dan@dennedy.org>
6 Last Revision: 2005-04-22
12 Services marked as "(Proprietary)" are not distributed with the GPL version
22 ffmpeg libavformat based producer for video and audio.
26 'file' - a filename specification or URL in the form:
27 [{protocol}|{format}]:{resource}[?{format-parameter}[&{format-parameter}...]]
28 For example, video4linux:/dev/video1?width:320&height:240
29 Note: on the bash command line, & must be escaped as '\&'.
30 Also, note the use of ':' instead of '=' for parameters.
31 Use 'ffmpeg -formats' to see a list of supported protocols
36 Format parameters only appear to be useful with 'video4linux' or
37 'audio_device' formats. For 'video4linux' the parameters are
38 width, height, frame_rate, frame_rate_base, and standard (ntsc|pal).
39 For 'audio_device' the parameters are channels and sample_rate.
41 Initialisation Properties
43 int video_index - index of video stream to use (-1 is off)
44 int audio_index - index of audio stream to use (-1 is off)
50 string resource - file location
51 double fps - this is fixed at 25 for PAL currently
52 double source_fps - the framerate of the resource
53 double aspect_ratio - sample aspect ratio of the resource
54 - this is determined on every frame read
58 ffmpeg must be configured as --enable-shared and installed prior
59 to compilation of mlt.
63 Audio sync discrepancy with some content.
64 Not all libavformat supported formats are seekable.
65 Ogg Vorbis is currently broken.
66 MPEG seeking is inaccurate - doesn't seek to i-frames so you may
67 get junk for a few frames.
68 RAW DV seeking not supported.
69 Fails to play beyond first frame of video of sources with PTS not
70 starting at 0 (video4linux).
76 A friendly giant that likes to rhyme and throw rocks
80 'file' - a filename specification:
81 [{mlt-service}:]{resource} | {mlt-service}
82 - can also be the name of a producer service that can
83 accept the resource specified post construction.
85 Initialisation Properties
89 + all producer initialising properties
93 string resource - file location
94 + all producer read only properties
98 This producer has two roles:
100 1. it handles the mappings of all file names to the other
102 2. it attaches normalising filters (rescale, resize and resample)
103 to the producers (when necessary).
105 This producer simplifies many aspects of use. Essentially, it
106 ensures that a consumer will receive images and audio precisely as
122 A simple colour generator.
126 colour - A colour value is a hexadecimal representation of RGB plus
127 alpha channel as 0xrrggbbaa.
128 - Also colours can be the words: white, black, red, green,
130 - The default colour is black.
132 Initialisation Properties
153 libdv based decoder for video and audio.
157 'file' - produce a/v from file
159 Initialisation Properties
166 string resource - file location
167 double fps - output frames per second
168 int length - duration of resource (in frames)
172 string quality - one of "best," "fast" or anything else chooses
181 DVCPRO is incorrectly identified as 16:9 aspect ratio. You must use
182 libdv from CVS or a post 0.101 release.
188 MainConcept based dv decoder for video and audio.
192 'file' - produce a/v from file
194 Initialisation Properties
201 string resource - file location
202 double fps - output frames per second
203 int length - duration of resource (in frames)
207 MainConcept DV or DVCPRO SDK, libdv.
208 "dv_sdk" installed parallel to mlt.
218 MainConcept based mpeg decoder for video and audio.
222 'file' - produce a/v from file
224 Initialisation Properties
231 string resource - file location
232 double fps - output frames per second
233 double aspect_ratio - sample aspect ratio of video
234 int length - duration of resource (in frames)
238 MainConcept MPEG SDK.
239 "mpeg_sdk_release" installed parallel to mlt.
255 Initialisation Properties
262 string resource - file location
263 double fps - output frames per second
264 double aspect_ratio - sample aspect ratio of video
265 int length - duration of resource (in frames)
279 A title generator that uses the Pango international text layout
280 and Freetype2 font renderer.
284 string file - a text file containing Pango markup, see:
285 http://developer.gnome.org/doc/API/2.0/pango/PangoMarkupFormat.html
286 - requires xml-like encoding special chars from:
287 <, >, & -to- <, >, &
291 Supplying a filename with extension ".txt" causes the Fezzik
292 producer to load with pango. If the filename begins with "+" the
293 pango producer interprets the filename as pango text. This is a
294 shortcut to embed titles in inigo commands. For westley, it is
295 recommended that you embed the title text in the property value.
297 Pango has builtin scaling. It will rescale the originally rendered
298 title to whatever the consumer requests. Therefore, it will lose
299 its aspect ratio if so requested, and it is up to the consumer to
300 request a proper width and height that maintains the image aspect.
302 Initialisation Properties
309 string markup - a string containing Pango markup see:
310 http://developer.gnome.org/doc/API/2.0/pango/PangoMarkupFormat.html
311 - requires xml-like encoding special chars from:
312 <, >, & -to- <, >, &
313 string fgcolour - an RGBA colour specification of the text
315 string bgcolour - an RGBA colour of the background rectangle
316 string align - paragraph alignment: left, centre, right
317 - also, numbers 0, 1 and 2 can be used respectively.
318 int pad - the number of pixels to pad the background rectangle
319 beyond edges of text. default 0.
320 string markup - see constructor argument
321 string text - non-markup string in UTF-8 encoding (can contain
322 markup chars un-encoded)
323 string font - the default typeface to use when not using markup.
324 default "Sans 48". FreeType2 renders at 72 dpi.
325 string encoding - the text encoding type of the input if not UTF-8.
326 - see 'iconv --list' for a list of possible inputs.
327 int weight - the weight of the font (default is 400)
331 string resource - the text/markup file or "pango" if no file.
332 int real_width - the original, unscaled width of the rendered title.
333 int real_height - the original, unscaled height of the title.
334 int width - the last requested scaled image width.
335 int height - the last requested scaled image height.
339 libpango-1.0, libpangoft2-1.0, libfreetype, libgdk_pixbuf-2.0,
340 libglib-2.0, libgobject-2.0, libgmodule-2.0, libfontconfig.
344 The foreground and background Pango markup span attributes are not
346 Word wrapping is not supported.
352 A still graphics to video generator using gdk-pixbuf
356 'file' - The name of a graphics file loadable by
357 a gdk-pixbuf loader. see /usr/lib/gdk-pixbuf/loaders
358 definitely png, jpeg, tiff, pnm, and xpm
359 - If "%" in filename, the filename is used with sprintf
360 generate a filename from a counter for multi-file/flipbook
361 animation. The file sequence ends when numeric
363 - If filename contains "/.all.", suffix with an extension to
364 load all pictures with matching extension from a directory.
365 - If filename contains the string "<svg", then pixbuf tries
366 to load the filename as inline SVG XML, which is convenient
371 Pixbuf has builtin scaling. It will rescale the originally rendered
372 title to whatever the consumer requests. Therefore, it will lose
373 its aspect ratio if so requested, and it is up to the consumer to
374 request a proper width and height that maintains the image aspect.
376 Initialisation Properties
380 int begin - when using an image sequence, this sets the starting
385 int ttl - how long (in frames) to repeat each picture in file
386 sequences. default is 25.
390 string resource - file location. See Constructor Argument above.
391 int real_width - the original, unscaled width of the rendered title.
392 int real_height - the original, unscaled height of the title.
393 int width - the last requested scaled image width.
394 int height - the last requested scaled image height.
398 libgdk_pixbuf-2.0, libglib-2.0, libgobject-2.0, libgmodule-2.0
402 XXX: in/out settings are incorrectly handled.
408 Reads a stream of contiguous PPM images.
412 command - a shell command to run something that produces ppm
415 Initialisation Properties
421 string resource - the command
429 Since it uses pipes, it is not compatible with bluefish.
435 Construct a service network from an XML description.
436 See docs/westley.txt.
440 URL - an XML text file containing westley XML (schema/DTD pending)
441 - Since westley files can be parameterised, the URL syntax is:
442 {file-name}[?{param-name}{'='|':'}{param-value}[&{param-name}{'='|':'}{param-value}...]]
443 A colon is allowed instead of an equal sign to pacify inigo,
444 who tokenises anything with an equal sign as a property
445 setting. Also, when running inigo from the shell, beware of
446 the '?' and shell filename expansion. You can surround the URL
447 with single quotations to prevent expansion. Finally, fezzik
448 will fail to match the filename when you use parameters, so
449 preface the url with 'westley:' to force fezzik to load with
454 string resource - file location
462 Non-referenced producers and playlists are not destroyed until the
463 network is destroyed.
464 A referenced producer or playlist must appear before the reference.
465 A filter that occurs before a producer has been defined causes a
472 OGG Vorbis file reader.
476 'file' - file to use (only .ogg supported at the moment)
478 Initialisation Properties
485 double fps - this is fixed at 25 for PAL currently
493 Fixed frame size (PAL audio chunks).
494 Doesn't cover ogg files with multiple, differing sections.
503 Shift the luma component using a constant value.
507 start - the constant floating point numeric value to apply.
510 Initialisation Properties
514 double start - see Constructor Argument above.
515 double end - the ending adjustment value. the filter interpolates
516 between the start and end adjustments over the
517 duration of the effect.
529 Does not go completely to black or white.
536 Copy audio from one channel to another channel.
540 to - the 0-indexed channel to copy into, default is 1.
545 int from - the channel from which to copy, default is 0.
561 Deinterlace a frame consisting of two fields using bob, weave,
562 greedy, one-field, and linear blend methods. This code is
563 appropriated from the Xine XV video output plugin.
567 method - a string containing the deinterlace method: bob, weave,
568 greedy, onefield, or linearblend. The default is
571 Initialisation Properties
586 If the frame properties "progressive" or "consumer_progressive"
587 are non-zero, then the filter is not applied. Also, if applied,
588 this sets the frame property "progressive" to 1.
596 Not a bug, but it only provides fair quality.
603 Adjust image luma using a non-linear power-law curve
607 gamma - a floating point value. The default is 1.0, or none.
609 Initialisation Properties
616 double gamma - the exponential factor of the power-law curve
631 Convert colour image to greyscale
637 Initialisation Properties
658 Scale the producer video frame size to match the consumer.
659 This filter is designed for use as a Fezzik normaliser.
663 interpolation - the rescaling method, one of:
664 nearest (lowest quality, fastest),
666 bilinear (default; good quality, moderate speed),
667 hyper (best quality, slowest).
669 Initialisation Properties
676 string interpolation - see constructor argument above
678 If a property "consumer_aspect_ratio" exists on the frame, then
679 rescaler normalises the producer's aspect ratio and maximises the
680 size of the frame, but may not produce the consumer's requested
681 dimension. Therefore, this option works best in conjunction with the
682 resize filter. This behavior can be disabled by another service by
683 either removing the property, setting it to zero, or setting
684 frame property "distort" to 1.
688 libgdk_pixbuf-2.0, libglib-2.0, libgobject-2.0, libgmodule-2.0
698 Creates Jack ports and runs a JackRack project to process audio
699 through a stack of LADSPA filters.
703 src - a JackRack file
707 If you are using a consumer that uses ALSA, then you should start
708 jacks with the dummy driver: jackd -d dummy.
709 I also recommend using a period size of 2048: -p 2048.
711 jackd -ddummy -r48000 -p2048
713 Initialisation Properties
718 The following can be used without a rack file in order to connect
719 filter_jackrack to a running instance of JackRack:
720 string out_1 - Jack port to connect MLT's output port (JackRack's input)
721 string out_2 - Jack port to connect MLT's output port (JackRack's input)
722 string in_1 - Jack port to connect MLT's input port (JackRack's output)
723 string in_2 - Jack port to connect MLT's input port (JackRack's output)
735 Jack, LADSPA, glib-2.0, libxml2
739 Currently, due to timing and synchronisation issues, the audio
740 is distorted with repeated samples and latency clicks.
741 no encapsulated resampling and jack runs at a fixed frequency
747 Runs a JackRack project to process audio through a stack of
748 LADSPA filters without using Jack.
752 src - a JackRack file
756 Due to audio integrity issues with the jackrack filter, this
757 filter is better for runtime, while jackrack is more suitable
758 for prototyping a rack file using the Jack Rack GUI.
760 Initialisation Properties
775 Jack, LADSPA, glib-2.0, libxml2
776 Jack is still required because this coexists with the jackrack
781 no encapsulated resampling and jack runs at a fixed frequency
787 Applies a luma transition between the current and next frames.
788 Useful for transitions from a slideshow created using producer
795 Initialisation Properties
806 int period - how long to wait between success iterations of the
807 transition. For best results set this to a multiple
808 of ttl used in pixbuf. The default is 24.
810 luma. - all properties beginning with "luma." are passed to the
811 encapsulated luma transition. For example, luma.out controls
812 the duration of the wipe.
816 transition_luma and its dependencies
826 Scale the producer video frame size to match the consumer.
827 This filter is designed for use as a Fezzik normaliser.
831 interpolation - the rescaling method, one of:
832 nearest (lowest quality, fastest),
833 bilinear (default; good quality, moderate speed),
834 hyper (best quality, slowest).
836 Initialisation Properties
843 string interpolation - see constructor argument above
845 If a property "consumer_aspect_ratio" exists on the frame, then
846 rescaler normalises the producer's aspect ratio and maximises the
847 size of the frame, but may not produce the consumer's requested
848 dimension. Therefore, this option works best in conjunction with the
849 resize filter. This behavior can be disabled by another service by
850 either removing the property, setting it to zero, or setting
851 frame property "distort" to 1.
855 the mainconcept rescaling sdk.
865 Provides various mirror and image reversing effects.
869 mirror - horizontal, vertical, diagonal, flip, flop
871 Initialisation Properties
873 int reverse - being 0 or 1
904 Initialisation Properties
906 string start - in the format X,Y:WxH[:PWxPY]
907 - PWxPY is the size of the averaging region in pixels.
908 string end - in the format X,Y:WxH[:PWxPY]
928 Apply one or more filters to a region of the video image. The region
929 can be shaped as well using the alpha channel of another producer.
933 resource - A file whose alpha channel will "shape" the region.
934 - The string "circle" is a shortcut but it requires pixbuf with
935 the librsvg loader. The circle is automatically stretched
936 to the region to create an ellipse.
938 Initialisation Properties
942 plus and region transition properties
946 see the region transition
954 "circle" is unpredictable in the absence of the librsvg pixbuf loader.
961 Adjust an audio stream's sampling rate, and duplicate channels if
962 producer provides less than consumer requested.
964 This filter is automatically invoked by Fezzik for the sake of
965 normalisation over inputs and with the consumer.
969 frequency - a numeric value for the new sample rate
971 Initialisation Properties
978 int frequency - the target sample rate
986 Assumes 2 channels during libsamplerate initialisation. Untested
993 Scale the producer video frame size to match the consumer.
994 This filter is designed for use as a Fezzik normaliser.
1000 Initialisation Properties
1007 If a property "consumer_aspect_ratio" exists on the frame, then
1008 rescaler normalises the producer's aspect ratio and maximises the
1009 size of the frame, but may not produce the consumer's requested
1010 dimension. Therefore, this option works best in conjunction with the
1011 resize filter. This behavior can be disabled by another service by
1012 either removing the property, setting it to zero, or setting
1013 frame property "distort" to 1.
1021 none but... it only implements a nearest neighbour scaling - it is
1022 used as the base class for the gtkrescale and mcrescale filters.
1028 Image scaling and padding and field order adjustment.
1032 Normally resize is used to pad the producer's
1033 output to what the consumer has requested after an upstream rescale
1034 filter first scales the image to maximise usage of the image area.
1035 This filter also adjusts the field order to lower field first
1036 if the frame property "top_field_first" has been set to 1.
1037 Therefore, when done, it sets the top_field_first to 0.
1038 This filter is automatically invoked by Fezzik as part of image
1039 sample aspect ratio normalisation.
1041 Constructor Argument
1043 scale - "affine" to use affine transform scaling, otherwise
1046 Initialisation Properties
1051 Read Only Properties
1061 Assumes lower field first output.
1067 Adjust an audio stream's volume level
1068 - based on the 'normalize' utility
1070 Constructor Argument
1072 gain - a string containing one of:
1073 - a floating point value of the gain adjustment
1074 - a numeric value with the suffix "dB" to adjust in terms of decibels
1075 - "normalise" to normalise the volume to the target amplitude -12dBFS
1077 Initialisation Properties
1081 int window - the number of video frames over which to smooth normalisation.
1086 string gain - same as constructor argument above
1088 string normalise - normalise the volume to the amplitude:
1089 - a numeric value with the suffix "dB" to set amplitude in decibels
1090 - a floating point value of the relative volume
1091 - an unspecified value uses the default -12dBFS
1093 string limiter - limit all samples above:
1094 - a numeric value with the suffix "dB"
1095 - a floating point value ( dB = 20 * log10(x) )
1096 - an unspecified value uses the default -6dBFS
1098 double max_gain - a floating point or decibel value of the maximum gain that
1099 can be applied during normalisation.
1100 - an unspecified value uses the default 20dB
1102 string end - a gain value just like the gain property above.
1103 This causes the gain to be interpolated from 'gain' to 'end'
1106 int window - the size of the normalising smoothing buffer in video frame units.
1107 - the smoothing buffer prevents erratic gain changes.
1108 - the default value is 75 video frames.
1110 gain can be applied as a factor to the normalise amplitude!
1124 Add a watermark to the frames.
1126 Constructor Argument
1128 resource - the producer to use (ie: a .png)
1130 Initialisation Properties
1132 string resource - the producer to use
1133 string factory - producer required for the resource ('fezzik')
1134 string geometry - composite geometry
1135 string distort - control scaling
1145 mlt core modules and optionally, fezzik
1158 A key-framable alpha-channel compositor for two frames.
1162 Performs dissolves and luma wipes in addition to alpha compositing.
1164 By default, the aspect ratio of the B frame is respected and the
1165 size portion of the geometry specification simply defines a
1168 This performs field-based rendering unless the A frame property
1169 "progressive" or "consumer_progressive" or the transition property
1170 "progressive" is set to 1.
1172 Constructor Argument
1176 Initialisation Properties
1180 string factory - The name of a factory service used as a non-PGM
1181 producer loader. The default is fezzik.
1183 Read Only Properties
1190 string geometry - key frame specification
1191 - this is a ; delimited form of the deprecated start,
1192 key[n], end properties
1193 int progressive - set to 1 to disable field-based rendering.
1194 string distort - when set, causes the B frame image to fill the WxH
1195 completely with no regard to B's aspect ratio.
1196 string halign - when not distorting, set the horizontal alignment
1197 of B within the geometry rectangle.
1198 - one of: left (0), centre (1), or right (2).
1199 - the default is left.
1200 string valign - when not distorting, set the vertical alignment of
1201 B within the geometry rectangle.
1202 - one of: top (0), middle (1), or bottom (2).
1203 - the default is top.
1204 string luma - the luma map file name. If not supplied, a dissolve.
1205 double softness - only when using a luma map, how soft to make the
1206 edges between A and B. 0.0 = no softness. 1.0 =
1208 Any property starting with "luma." is passed to the non-PGM luma
1211 Deprecated Properties
1213 string start - a geometry specification as X,Y:WxH[!][:mix]
1214 - X, Y, W, H are assumed to pixel units unless they
1216 - '!' is a shortcut to specify distort, see below.
1217 - mix is always a 2 digit percentage, defaults to 100.
1218 - default is "85%,5%:10%x10%"
1219 string end - the ending size and position.
1220 string key[F] - X,Y:WxH[:mix] - set a key frame for geometry between
1221 the in and out. F is a frame number and can be
1222 negative to make it relative to the out point.
1230 Assumes lower field first during field rendering.
1236 A generic dissolve and wipe transition processor.
1241 from how it uses a grayscale "map" file. As the luma value varies
1242 over time, a threshold filter is applied to the map to determine
1243 what parts of frame A vs. frame B to show. It reads PGM files
1244 up to 16 bits! Alternatively, it can use the first frame from any
1245 producer that outputs yuv, but it will be limited to the luma
1246 gamut of 220 values.
1247 This performs field-based rendering unless the A frame property
1248 "progressive" or "consumer_progressive" or the transition property
1249 "progressive" is set to 1.
1251 Constructor Argument
1253 string resource - the luma map file name - either PGM or any other
1255 - If not supplied, a dissolve.
1257 Initialisation Properties
1261 string factory - The name of a factory service used as a non-PGM
1262 producer loader. The default is Fezzik.
1266 string resource - same as above
1267 double softness - only when using a luma map, how soft to make the
1268 edges between A and B. 0.0 = no softness. 1.0 =
1270 int reverse - reverse the direction of the transition.
1271 Any property starting with "producer." is passed to the non-PGM luma
1274 Read Only Properties
1284 Assumes lower field first output.
1290 An two stream audio mixer.
1292 Constructor Argument
1296 Initalisation Properties
1303 double start - the mix level to apply to the second frame.
1304 - any negative value causes an automatic crossfade from 0 to 1.
1305 double end - the ending value of the mix level. mix level will be interpolated
1306 from start to end over the in-out range.
1307 int reverse - set to 1 to reverse the direction of the mix.
1309 Read Only Properties
1319 Samples from the longer of the two frames are discarded.
1326 Apply zero or more filters to B frame as it is composited onto
1327 a region of the A frame. The "shape" of the region can be defined
1328 by the alpha channel of a third producer.
1330 Constructor Argument
1332 resource - a shape producer
1334 Initialisation Properties
1336 string resource - nothing is rectangle, "circle" is a pixbuf-
1337 generated SVG circle, anything else is loaded by the factory.
1338 string factory - the service that creates the shape producer.
1339 - the default is fezzik.
1340 string filter[N] - one or more filters to apply. All filter
1341 properties are passed using the same filter "key"
1342 Any property starting with "composite." is passed to the
1343 encapsulated composite transition.
1345 Read Only Properties
1351 transition_composite
1365 Multiformat transcoding consumer.
1367 Constructor Argument
1369 string target - the filename to write to, e.g. test.mpeg.
1371 Initialisation Properties
1373 int buffer - the number of frames to buffer, minimum 1, default 25.
1374 string rescale - a rescale method, see the Filters/rescale.
1375 int progressive - indicates whether to use progressive or field-
1376 based rendering, default 0 (off).
1378 Read Only Properties
1390 bluefish (Proprietary)
1394 BlueFish444 audio and video output module.
1396 Constructor Argument
1398 card - a numeric card id starting at 1, default is 1.
1400 Initialisation Properties
1402 string standard - "PAL" (default) or "NTSC"
1403 - default is based upon MLT_NORMALISATION
1404 environment variable, which defaults to PAL.
1405 int frames - the number of DMA video frames. default is 8.
1406 minimum is 2. maximum on my system is 11.
1407 int buffer - the number of frames to buffer within MLT, minimum 1,
1409 string rescale - a rescale method, see the Filters/rescale.
1411 Read Only Properties
1417 BlueVelvet SDK installed parallel to mlt in "bluefish."
1421 Does not work with any service that uses pipes!
1423 If mlt crashes, you might need to reload the BlueDriver kernel
1424 module due to unreleased DMA buffers.
1426 Only supports 2 channel audio at the moment.
1434 Constructor Argument
1436 string target - the filename to write to, e.g. /dev/dv1394.
1438 Initialisation Properties
1440 int buffer - the number of frames to buffer, minimum 1, default 25.
1441 string rescale - a rescale method, see the Filters/rescale.
1445 int progressive - indicates whether to use progressive or field-
1446 based rendering, default 0 (off).
1448 Read Only Properties
1464 Mainconcept MPEG encoder.
1466 Constructor Argument
1468 string target - the filename to write to.
1470 Initialisation Properties
1472 int buffer - the number of frames to buffer, minimum 1, default 25.
1473 string rescale - a rescale method, see the Filters/rescale.
1474 string format - vcd [default], svcd or dvd provide base settings
1475 int motion_search_type - 0 to 16 - reduces quality/cpu usage
1476 int gop - group of picture size (default: format dependent)
1480 int progressive - indicates whether to use progressive or field-
1481 based rendering, default 0 (off).
1483 Read Only Properties
1489 Mainconcept MPEG SDK
1499 Simple DirectMedia Layer audio and video output module.
1501 Constructor Argument
1503 string video_standard - "PAL" (default), "NTSC", or "WxH"
1505 Initialisation Properties
1507 int buffer - the number of frames to buffer, minimum 1, default 25.
1508 string rescale - a rescale method, see the Filters/rescale.
1509 - Hint: "none" works very good with SDL output.
1513 double volume - audio level factor
1514 int video_off - if 1, disable video output
1515 int audio_off - if 1, disable audio output
1517 int progressive - indicates whether to use progressive or field-
1518 based rendering, default 0 (off).
1519 int audio_buffer - size of the sdl audio buffer (default: 1024)
1521 Read Only Properties
1527 libSDL-1.2, libasound, libaudio, libXt, libX11, libXext, libSM, libICE
1537 Serialise the service network to XML.
1538 See docs/westley.txt for more information.
1540 Constructor Argument
1542 resource - the name of a file in which to store the XML.
1543 - stdout is default.
1545 Initialisation Properties
1547 string resource - same as above.
1555 Untested arbitrary nesting of multitracks and playlists.
1556 Property "id" is generated as service type followed by number if
1557 no property named "id" exists, but it fails to guarantee uniqueness.