Lumiera
The new emerging NLE for GNU/Linux

State

Parked

Date

2007-06-07

Proposed by

ct

Render Optimizer

Render only parts of a frame which are necessary for the Output; optimize render pipeline for efficiency

Description

This Idea is just stored here for later reference/implementation.

Effects give some information on which data their output depends (like transitions, temporal dependencies, color/alpha etc) and what the operation costs. Based on this information we optimize the render pipeline, for example if the output is a zoom, then we only need to calculate the parts of a frame which will be viewable in the output (plus some more dependencies, like blur has radius and so on). Further in some cases it might be favorable to reorder some effects for the actual render process, as long it would produce the same output as the original sequence of effects.

Comments

Possible classification for video filters:

  1. The filter only changes the color of each pixel in the same way

  2. The filter deforms the image but leaves the color

  3. The filter makes complex things. The only additional hint it can export is the number of referenced past frames, if such a limit exists (sometimes it doesn’t).

Filters of type 1 and type 2 never use any previous frames, and are strictly one frame in — one frame out. Filters of type 1 can always be swapped with filters of type 2, the output is the same. All other filters cannot be swapped in general.

The good news is, that:

  1. All commonly used filters are either type 1 or type 2 (type 3 are more the fun effects)

  2. Filters of type 2 are colormodel agnostic

  3. If a filter of type 1 makes only linear transformations of the color vectors
    (i.e.: new_color ≔ matrix · old_color), then the matrix can be transformed from e.g. RGB to YUV, so these filters can always work in both colorspaces directly

State → Parked

Generally this is accepted but needs some more polishing when we go over it.

Christian Thaeter

Thu 14 Apr 2011 03:06:42 CEST

Reassessment : remains valid

Relevance confirmed 2025. This RfC is written narrow enough to just define the goal of an optimised render pipeline — which was and is a central goal of the Lumiera project.

Approaching this topic however requires much more work and notably a detailed analysis of the possibilities, based on facts and measurements. There is the real danger to get attached to some implementation idea deemed enticing, leading to very specific tweaks which limit the ability to adapt to other relevant requirements.

Furthermore, since Lumiera aims at being library / framework agnostic, a significant difficulty to overcome first is the build-up of an abstract framework to describe and engage viable optimisations, which can then be applied as transformations within the Builder — quite similar to the proceedings of an optimising compiler. The description of possible optimisations likely involves elements of knowledge representation, combined with heuristical aspects, possibly augmented by machine learing.

To summarise: this is a long-term vision.

Ichthyostega

2025-09-20

Back to Lumiera Design Process overview