Skip to Main content Skip to Navigation
Journal articles

Vectorising Bitmaps into Semi-Transparent Gradient Layers

Christian Richardt 1 Jorge Lopez-Moreno 1 Adrien Bousseau 1 Maneesh Agrawala 2 George Drettakis 1 
1 REVES - Rendering and virtual environments with sound
CRISAM - Inria Sophia Antipolis - Méditerranée
2 Visualization Lab
Computer Science Division [Berkeley]
Abstract : We present an interactive approach for decompositing bitmap drawings and studio photographs into opaque and semi-transparent vector layers. Semi-transparent layers are especially challenging to extract, since they require the inversion of the non-linear compositing equation. We make this problem tractable by exploiting the parametric nature of vector gradients, jointly separating and vectorising semi-transparent regions. Specifically, we constrain the foreground colours to vary according to linear or radial parametric gradients, restricting the number of unknowns and allowing our system to efficiently solve for an editable semi-transparent foreground. We propose a progressive workflow, where the user successively selects a semi-transparent or opaque region in the bitmap, which our algorithm separates as a foreground vector gradient and a background bitmap layer. The user can choose to decompose the background further or vectorise it as an opaque layer. The resulting layered vector representation allows a variety of edits, such as modifying the shape of highlights, adding texture to an object or changing its diffuse colour.
Document type :
Journal articles
Complete list of metadata

Cited literature [24 references]  Display  Hide  Download
Contributor : Team Reves Connect in order to contact the contributor
Submitted on : Thursday, September 4, 2014 - 11:58:44 AM
Last modification on : Monday, July 25, 2022 - 3:44:25 AM
Long-term archiving on: : Friday, April 14, 2017 - 1:02:34 PM


Files produced by the author(s)


  • HAL Id : hal-01060820, version 1


Christian Richardt, Jorge Lopez-Moreno, Adrien Bousseau, Maneesh Agrawala, George Drettakis. Vectorising Bitmaps into Semi-Transparent Gradient Layers. Computer Graphics Forum, Wiley, 2014, Proceedings of Eurographics Symposium on Rendering (EGSR), 33 (4). ⟨hal-01060820⟩



Record views


Files downloads