The process of marking a template target is fairly complex, has its limitations and cannot be used in every project. Limiting factors include:
• The amount of ‘noise’ in an image. Competing, relatively high contrast artifacts on or around a target can confuse the template target marker, especially when trying to mark idealized targets. Best results will be achieved when targets are very distinct on a clean background.
• The amount of distortion of a target. Although the target marker is robust enough to compensate for targets that are distorted due to perspective, if the target is too distorted, the target marker will have trouble matching the shape with the template.
• Target size variances. The target marker will compensate for changes in target size due to perspective. However, if the target size varies too much between images, target marking may not be consistent. It is best to use templates of a size that will at least somewhat resemble the target sizes in your image.
The Targets - Do’s and Don’t’s section mainly refers to circular target marking, but also has information that applies to template target marking.