This past week, I worked on camera recognition using the openMV camera. This included recognition of different colored blobs, as well as recognition of April tags.
To test the camera's April tag recognition, I put April tags on the wall and tested the distance that the April tags could be detected from. As you can see in the pictures below, the camera was unable to recognize all three tags at the same time, although it did correctly identify each of them individually (and occasionally two at the same time). This was at a distance of 1.82 meters (6 feet).
.jpg "openMV_apriltagtest_Moment%282%29")
The camera was unable to identify the tags at distances much larger than 2 meters using the original setup. In order to increase the range, I changed the frame size that the camera was viewing, effectively zooming in on the April tags. This zoom gave the camera the ability to identify the tags from farther away, although it also limits the area that the camera can search for tags at one time. The picture below was taken at a distance of about 2.74 meters (9 feet), and was also in far worse lighting conditions. The picture is very dark, but the camera was able to correctly identify the tags at a longer distance. In the future, I intend to continue testing the range of the camera in different lighting conditions, in order to determine the limits and attempt to improve the range at which the tags can be recognized.
