Lumiera
The new emerging NLE for GNU/Linux

Lumiera is to be a professional tool for video editing on GNU/Linux systems. The vision of the development team defines a modern design for the core of a Non-Linear Editing software. A key aspect of Lumiera is the strong separation between the user interface and the processing core. We are developing Lumiera with a GTK GUI but that will in no way be exclusive; other GUIs can be written, as well as scripts to drive the core. This becomes possible by an ongoing effort to decrease coupling. Each major component in the application strives to be open to extensions, but closed against external modification. The presentation, the model and the “performing” of the model are separate and self-contained parts of the application. Lumiera as a processing core will be able to perform any conceivable task on video and audio, maybe even tasks entirely unrelated to video editing.

Workflow

The word “workflow” is used to name the way tasks can be achieved in an application. Any operation in Lumiera must be possible in the most suitable and stringent fashion. The workflow is closely related to how flexible the GUI is but is also the concern of deeper and more technical parts of the application.

Overview

Lumiera is built from numerous subsystems. This overview will provide a general description of the major components from the highest to the lowest level. Lumiera is composed of three main areas with a few additional extra components. We discuss these areas below.

Graphical User Interface

User interfaces are implemented as plug-ins. As a consequence, it is possible to interface with Lumiera through scripts. It is also possible to create specialised GUIs. The interface is the component that is closest to the user. It provides purely visual interaction with the user. Within this work environment, the user manipulates, organizes, loads, configures all sorts of data, especially MObjects (media objects) and Assets. These elements are contained within a structure called the Session.
GUI design documents

The Processing Layer

The processing layer (“Proc-layer” or “proc”) covers several closely related aspects. When the user works with the GUI, all the clips, effects and other visually presented components are actually stored within the Session model (“high-level model”). Any editing operation initiated by the user is actually executed in the context of the session. Next, after each change, a component known as the Builder assembles the contents of this session model to transform them into a network of nodes, which can be efficiently performed for rendering. Often, we refer to this node structure as the “low-level model”. On rendering or playback, the Proc-layer is responsible for accessing this low-level node structure to generate individual frame render jobs, ready to be handed over to the backend, which finally initiates the actual rendering calculations.
→ more about the Model
→ design of the Engine subsystem

The Backend

The backend attaches to the low-level model and the render jobs generated by Proc. It actually conducts the rendering operations and makes heavy use of the Input/Output System for accessing media content and sending generated data to the screen or to external output.
Backend design level documents
technical documentation

Extra Components

The Application

The application controls the initialization and shutdown procedures as well as loading external elements such as plug-ins, which are widely used throughout Lumiera. It acts as the framework which supports core component operations. This framework is complemented by a library of commonly used components, algorithms and data structures.
Application framework

Plugins

Plug-ins play an important role within Lumiera since the application relies heavily on current FLOSS implementations and external libraries. Moreover, the application will be configurable and can be extended in various ways; whenever some extension isn’t permanent or will be used only on demand, it is packaged as a separate module into a plug-in. For example, the GUI of Lumiera is a plugin.
→ design documents regarding the Plugins