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