2 short-description: GStreamer Editing Services API reference.
5 # GStreamer Editing Services
7 The "GStreamer Editing Services" is a library to simplify the creation
8 of multimedia editing applications. Based on the GStreamer multimedia framework
9 and the GNonLin set of plugins, its goals are to suit all types of editing-related
12 The GStreamer Editing Services are cross-platform and work on most UNIX-like
13 platform as well as Windows. It is released under the GNU Library General Public License
16 ## Goals of GStreamer Editing Services
18 The GStreamer multimedia framework and the accompanying GNonLin set of
19 plugins for non-linear editing offer all the building blocks for:
21 - Decoding and encoding to a wide variety of formats, through all the
22 available GStreamer plugins.
24 - Easily choosing segments of streams and arranging them through time
25 through the GNonLin set of plugins.
27 But all those building blocks only offer stream-level access, which
28 results in developers who want to write non-linear editors to write a
29 consequent amount of code to get to the level of *non-linear editing*
30 notions which are closer and more meaningful for the end-user (and
31 therefore the application).
33 The GStreamer Editing Services (hereafter GES) aims to fill the gap
34 between GStreamer/GNonLin and the application developer by offering a
35 series of classes to simplify the creation of many kind of
36 editing-related applications.
40 ### Timeline and TimelinePipeline
42 The most top-level object encapsulating every other object is the
43 [GESTimeline](GESTimeline). It is the central object for any editing project.
45 The `GESTimeline` is a `GstElement`. It can therefore be used in any
46 GStreamer pipeline like any other object.
50 The GESTimeline can contain two types of objects (seen in
53 - Layers - Corresponds to the user-visible arrangement of clips, and
54 what you primarily interact with as an application developer. A
55 minimalistic timeline would only have one layer, but a more complex
56 editing application could use as many as needed.
58 - Tracks - Corresponds to the output streams in GStreamer. A typical
59 GESTimeline, aimed at a video editing application, would have an
60 audio track and a video track. A GESTimeline for an audio editing
61 application would only require an audio track. Multiple layers can
62 be related to each track.
64 ![Layers and Tracks](images/layer_track_overview.png)
66 In order to reduce even more the amount of GStreamer interaction the
67 application developer has to deal with, a convenience GstPipeline has
68 been made available specifically for Timelines : [GESPipeline](GESPipeline).