This week, I reviewed and studied on the color space to find the proper one for the color decomposition for the traffic sign content analysis. This is based on the analysis result done last week (Please read Result analysis for the further improvement) that the entropy-maximized line receptors directly applied to the raw traffic signs are not good enough in classification.
In traffic signs, colors whether used in the background or legends are very important in classifying the traffic sign categories. However, existing approaches are just mentioning that they used a specific color space without justified testing results applied to the real traffic sign scenes. I think that this experiment should be done and very important to find the proper color space specifically for traffic sign color decomposition or extraction from the real scene. I also found that there was some error in my previous color decomposition approach that the color information supplied at  is not matched with the real color using in printing the traffic signs. Hence, for following weeks, I will do survey and analysis on this topic and intermediate progress are summarized at here: Choosing a proper color space