VIS-IT The 3 Steps to filtering Open an image The user can either select an image from our pre-existing library or choose to upload an image from their own computer. Choose A Filter The user selects a filter to apply to the image in order to view the image how a person suffering from a color deficiency sees the image. Apply filter The filter is applied to the original image and a new filtered image is displayed. Filtered images can then be saved or printed. The Filtering Process The filtering works by running an algorithm over each pixel of an image. The algorithm is based on one developed by Brettel, Viénot and Mollon, which converts RGB pixel values into their LMS equivalent using a transformation matrix. Then the LMS values are corrected for the type of colour vision deficiency with some simple vector multiplication and converted back to RGB for redisplaying. The LMS co-ordinates are the Long, Medium and Short wave colour receptors in the eye. The types of colour vision deficiency we are dealing with correspond to one of those receptors not functioning. The algorithm removes the non-functional receptor and replaces it with the reduced stimuli version. VIS-IT has been designed and Implemented by: Bader Buallay - Computing and Accounting and Finance. Christopher Frost - Computer Science. Sophia Rainford - Computing and Philosophy. VIS-IT is a tool designed to teach individuals about colour vision deficiencies. For a person suffering from a colour vision deficiency, everyday tasks such as watching the weather forecast or even reading a webpage can become near to impossible. VIS-IT allows users to upload their own images and view them how a person suffering from a Protanopia, Deuteranopia or Tritanopia colour vision deficiency views them. Possible Extensions We plan to extend VIS-IT in the following ways: HTML Parser- This will allow designers to check that their work is accessible to people with colour vision deficiencies. ClearView- Create a clear window that filters anything placed under it by the selected filter. The user can drag the window around the desktop in order to see how the Operating System and other applications are viewed by people suffering with colour vision deficiencies Colour Vision Deficiencies Protanopia, Deuteranopia and Tritanopia are all forms of Dichromacy colour deficiency; where photoreceptors of a specific colour (red, green or blue) are either not functioning or absent within the retina. Those with Dichromacy (Dichromats) may see certain colours without any problem, they may however, confuse certain colours depending on the form of colour deficiency they suffer. Protanopia: Those who suffer from protanopia confuse the colours red and green due to missing/malfunctioning red photoreceptors. This form of colour deficiency is present in 1% of all males and in less than 1% of all females. Deuteranopia: Those who suffer from deuteranopia are similar to those who suffer from protanopia in that they confuse the colours red and green however those who suffer deuteranopia confuse colours because of missing/malfunctioning green photoreceptors. This form of colour deficiency is present in 1% of all males and in less than 1% of all females. Tritanopia: A very rare form of colour deficiency where an individual can perfectly perceive red and green however has troubles distinguishing between the colours blue and yellow. This form of colour deficiency is present in less than 1% of all males and in less than 1% of all females. Colour Spectrum Taken from: essibility_color_challenged.html