Accessing ColorMatcher step results

Results of the ColorMatcher step are indicated in the Results pane. The ColorMatcher step also provides image results, as previously discussed in the Output images subsection of the Procedure for using the ColorMatcher step section earlier in this chapter.

Results are organized by region. For each region, the following details are available:

Best match.
Status.
Match Score.
AreaRelevance.
Distance (when Match set to Areas only).
Pixel Count (when Match set to Pixels only).
Area Pixel Count.
Sample Coverage (when Match set to Pixels only).
Outlier Coverage (when Match set to Pixels only).

When using the multiple regions (repeated regions) feature, the results for each region are indexed per occurrence of the fixture provider.

At design-time, you can also use the Quick Evaluate pane to examine the value of a feature. To change the index, move the cursor over the item in parentheses, and when the cursor changes shape (from an arrow to a hand), click to pop up the selection box.

Basic results

In the Results pane, the main rows indicate the match region results and, expandable underneath, are sub-rows indicating the results of the color-samples, as they apply to that specific match region. Color-sample results are within, and therefore specific to, a match region.

Results can apply to match regions, color-samples, or both. For example, the AreaRelevance only applies to the match region, while the Distance applies to the match region and the color-sample of that match region. However, the match region Distance indicates the color difference between the match region and the best match color-sample (if there is one), while the color-sample Distance indicates the color difference between the match region and that color-sample, even if it is not the best match.

An important result is typically the Best Match, which indicates the color-sample that most matches the match region. In addition to accessing this result from the Results pane, you can get this result, as well as other key results, by hovering on the match region in the image.

Note: Although the Best Match is the best possible match in the image, it still might not be good enough to pass. It is important to check the status of an area before checking the best match.

Match score and area relevance score

The ColorMatcher step calculates 2 main score results, in percent: the MatchScore and the AreaRelevance. For a match to have a pass status, the lowest limit for each score must be reached. To set the lowest limits, use the Minimum score and the Minimum area relevance settings in the Configuration pane. Typically, you will not need to modify these settings, however you can do so if you are having difficulty distinguishing the best match color-sample. Note that the match score and area relevance score can vary depending on the color space and color distance calculation.

The MatchScore result applies to the color-sample and indicates its similarity to the match region. In general, the higher the score, the closer the colors. If you are using an Areas match strategy, you will receive a MatchScore of 100% only if the color-sample is absolutely identical to the match region. For a MatchScore of 100% when using a Pixels match strategy, all pixels in the match region that are not outliers must vote for the same color-sample.

The AreaRelevance score result applies to the match region and indicates the significance (relevance) of the MatchScore result. For example, a high AreaRelevance score implies that the best match color-sample is a vastly superior match when compared to the other possible color-sample matches, while a low AreaRelevance score suggests that another color-sample is very close to being the best match.

If you are using an Areas match strategy, you will receive an AreaRelevance score of 100% only if the best match color-sample is the only color-sample considered. This can occur if all other color-samples fall outside of the distance tolerance. For an AreaRelevance score of 100% when using a Pixels match strategy, all pixels in the match region must vote for the same (best match) color-sample.