With the increased use of multimedia technologies, image compression has become increasingly popular. Compression decreases the high demands for storage capacity and transmission bandwidth. However, when compressing an image, some part of the information is lost, since the compression smoothes high frequencies thereby distorting small details. This issue is crucial, especially in military, spying and medical systems. When planning these kinds of systems, the image compression quality must be considered as well as how it affects the mission performance carried out by the user. Our goal is to examine the behavior of the human eye during image scanning and try to quantify the effect of image compression on observer tasks such as target acquisition. For this task, we used the standard JPEG2000 in order to compress the images at different compression ratios ranging from 10% (the highest) to 100% (the original image). It was found that animation images were more influenced by compression than thermal images. In general, as the compression ratio increased the ability to acquire the targets decreased.