The purpose of this paper is to design and to implement proper color modification methods for enhancing visual perception of digital images for people with protanopia (one of the types of Color Vision Deficiency). This paper proposes one simulation method and two daltonization methods for the modification of digital colored images, implementing the additional step of quantization for a faster modification of colors which are not correctly perceived. In order to avoid color confusion a color checking module is implemented and optimal daltonization parameters are selected. The ultimate objective of this paper is to minimize the total processing time to such an extent that it is possible to apply the proposed methods to real-time sequences (online video). The entire application is tested in a set of artificial and real images, while the performance of the proposed algorithms is evaluated in an appropriately selected set of colored images.