Video Sequence Editor Improvements - Individual strip previews and modification indicators - Proposal


Aditya Y Jeppu


Email :, d.b.o, devtalk : @quantimoney
Linkedin : adityayjeppu


The project focuses on the strips (video and image/sequence) in the video sequencer. The main goal is to add a preview of the clip in the corresponding strip of the sequencer to replace the current flat colour rectangles and, if time permits, to provide visible icons on the strip representing any strip modifications made by the user.


The current look of the strips in the sequencer has no indication of the clip it represents other than the name of the file. Similar file names and truncated display text in the smaller strips can lead to confusion in the orientation of the clips. Each clip cannot be viewed individually to check the contents. Enabling the ability to see the clip frames in the strips area will aid the user in basic strip layout tasks. Icons representing strip modifications for individual strips in the sequencer will provide a unified view of all changes (modifier wise), that can aid the user to keep track of the changes made and check the uniformity of changes across multiple strips.


The final result is an improved sequencer with the strips (of the video and the image/sequence) containing additional information. Each strip has

  • the preview of the clip
  • the icon representing the modifications applied.

The icons are there to only represent the pre-existing modifications which are already in blender. No new modifiers are proposed.

Project Details

Currently, blender uses flat rectangular colour tiles to represent individual clips in the video sequencer. A preview of the proposed final video sequencer UI is provided in the figures below (Figures a,b,c). Figure (a) shows a clip with the preview image. Here, the small rectangle width(vertical) for the strip should be changed to a default larger size to incorporate a clear enough view of the preview image(s) when a new movie clip strip is added. The preview image can be cut to the appropriate length of the strip as shown in (a). When the length (horizontal) of the strip is wide enough, multiple equally distributed frames of the video clip can be used as preview, with equal gaps between each frame, as shown in Figure (b). The size of each frame in this case is set based on the available width (vertical) of the rectangular strip and in accordance to the aspect ratio of the actual clip. For long strip thumbnail views, the number of such frames depend on the length of the rectangle strip.

This involves modifications to sequencer_draw.c and sequencer.c, providing a means to generate, store and draw the thumbnails. Drawing thumbnails might have to be its own operation to avoid slowing down the UI and the images loaded could be only those which are in view. This is done only for movie clip strips and image sequences. The display of the file name, waveforms and the handles on either side also would be layered over the thumbnails for a clean interface.

For the second half of the project, the icons for each of the modifiers will be provided in the positions represented by the white squares in Figure(c) . The icons can be shown only when the modifiers are applied and are arranged in alphabetical order, taking no more space than required. This should be done to have a uniform ordering of the icons, even when some icons aren’t needed. New icons for each modifier need to be designed and will be based on the blender icons design. This will require discussions with the UI team and done once the strip previews are working.

Timing Considerations

Due to the pandemic, my undergraduate college calendar has shifted and I have my final semester examinations spread across the month of August. So, I have chosen a relatively easy topic to account for conflicts with the GSoC coding period. I also have tests during the last week of June and July. Therefore, my primary goal for the project is the work on clip previews for the sequencer and I will continue to work on the icons if time permits. That leaves me around 6 weeks for intensive coding, plus any additional work that can be done before the coding period, especially project planning and in depth understanding of the related portions of the codebase to identify what changes can be made.


I am a 2nd year BTech student studying Computer Science and Engineering at RV College of Engineering, Bangalore, India. I am 20 years old. I started using Blender in 2013-14 by trying a step by step tutorial on making the street scene from the Inception movie. This gave me a good hold of the basics but I predominantly used blender for patent models and simulations. Over the last year I saw the true power of blender for art following artists like Ian Hubert and I wanted to contribute to Blender development. I have used C for over two years now and also have prior python experience. I have a good understanding of the blender code especially the sequencer code like adding and drawing strips, background UI and scroll bar, the overlays for the strips, Image Buffer and MovieClip structures and how they are used.