Effectiveness & Efficiency

The "preparation" program is relatively quick to calculate, save, and load points of interest. The heavier phase is the stage of calculating feature points using KAZE. Although it is a fast algorithm, it can take some time to calculate and save depending on the system you are running on.

Calibration of the camera takes place very quickly, however, a slight delay of 500 ms has been introduced for each image, in order to allow the user to verify if the pattern to be searched in the image was actually identified.

The "augment" program is also relatively quick to calculate the compass and center. It may take some time if there are a considerable number of points of interest to calculate the distance. Since you use KAZE to calculate the feature points of the zoom image, it may take some time depending on the system you are running on. The calculation of the homography matrix is instantaneous, as is the inverse homography. In "debug" mode the algorithm still presents the matches between the original image and the augmented; the original image with the transformations of the homography matrix; the augmented image with the transformations of the inverse matrix of homography. These calculations can also take some time. The time does not scale depending on the size of the images because, before being processed, the images are uploaded and resized to a maximum width and height of 1000 pixels and 600 pixels respectively. The ratio of width to height is maintained. An "INTER_AREA" interpolation is used to do the resizing.

Regarding the efficacy of the results, they depend a lot on the type of map, in this case, a satellite image of Porto was used, which allowed KAZE to obtain hundreds of feature points. This allowed for a very accurate homography matrix that results in a very credible and realistic "augment".