Method and arrangement for estimating at least one cross-channel colour mapping model from an set of tuples of corresponding colours relative to at least two images

Patent metadata

Field	Value
Publication number	US-10116919-B2
Application number	US-201314442748-A
Country	US
Kind code	B2
Filing date	Nov 5, 2013
Priority date	Nov 14, 2012
Publication date	Oct 30, 2018
Grant date	Oct 30, 2018

Abstract

The present invention generally relates to a method and arrangement for estimating said at least one cross-channel color mapping model from a set of tuples of corresponding colors relative to at least two images. The method is characterized in that it uses a processor for selecting at least one intermediate tuple of corresponding colors from the set of tuples of corresponding colors by using at least one channel-wise color mapping model, and for estimating the at least one cross-channel color mapping model from the at least one intermediate selected tuple of corresponding colors.

First claim

The invention claimed is:

1. A method for compensation of colour differences between at least two images imaging a same scene, the colours of which are represented according to m colour channels, comprising:
extracting from said images a set of tuples of corresponding colours;
estimating from said set of tuples of corresponding colours a channel-wise colour mapping model for each of said m colour channels;
selecting within said set of tuples of corresponding colours at least one intermediate tuple having colours with a difference to said estimated channel-wise colour mapping model that are smaller than a determined threshold;
estimating from said at least one selected intermediate tuple of corresponding colours at least one cross-channel coulour mapping model for at least one of said m colour channels;
generating a final set of final tuples of corresponding colours from said at least one selected intermediate tuple of corresponding colours such that said final tuples have colors with a difference to said estimated cross-channel colour mapping model that are smaller than a determined threshold; and
compensating colour difference between said images based on said final set of final tuples of corresponding colours.

2. The method for compensation of colour differences according to claim 1 , wherein said extracting is based on matching feature points between said images.

3. The method for compensation of colour differences according to claim 1 , wherein estimating the channel-wise colour mapping model for each of said m colour channels is performed such as to model, in said colour channel, colour differences between colours of each tuple.

4. The method for compensation of colour differences according to claim 1 , wherein said at least one cross-channel colour mapping model is based on thin plate splines.

5. An arrangement for compensation of colour differences between at least two images imaging a same scene, the colours of which are represented according to m colour channels, comprising:
a processor coupled to a memory, the processor being configured to:
extract from said images a set of tuples of corresponding colours;
estimate from said set of tuples of corresponding colours a channel-wise colour mapping model for each of said m colour channels;
select within said set of tuples of corresponding colours at least one intermediate tuple having colours with a difference to said estimated channel-wise colour mapping model that are smaller than a determined threshold;
estimate from said at least one selected intermediate tuple of corresponding colours at least one cross-channel coulour mapping model for at least one of said m colour channels;
generate a final set of final tuples of corresponding colours from said at least one selected intermediate tuple of corresponding colours such that said final tuples have colors with a difference to said estimated cross-channel colour mapping model that are smaller than a determined threshold; and
compensate colour difference between said images based on said final set of final tuples of corresponding colours.

6. The arrangement for compensation of colour differences according to claim 5 , wherein said extracting is based on matching feature points between said images.

7. The arrangement for compensation of colour differences according to claim 5 , wherein estimating the channel-wise colour mapping model for each of said m colour channels is performed such as to model, in said colour channel, colour differences between colours of each tuple.

8. The arrangement for compensation of colour differences according to claim 5 , wherein said at least one cross-channel colour mapping model is based on thin plate splines.

Assignees

• Thomson Licensing

Inventors

• Sheikh Faridul Hasan
• Stauder Jurgen
• Jolly Emmanuel

Classifications

• H04N1/6058

  Reduction of colour to a range of reproducible colours, e.g. to ink- reproducible colour gamut · CPC title

• H04N1/6063

  dependent on the contents of the image to be reproduced · CPC title

• H04N13/15 Primary

  for colour aspects of image signals · CPC title

• H04N1/6061

  involving the consideration or construction of a gamut surface · CPC title

• G01J2003/466

  Coded colour; Recognition of predetermined colour; Determining proximity to predetermined colour · CPC title