parker@mprvaxa.UUCP (Ross Parker) (03/01/86)
Can anyone describe to me or let me know where I can find a method of calculating pixel colours for the following situation: I have a 2D colour raster image. Each pixel in the image has associated with it an index into a colour table, where each entry in the colour table contains a field for red, green, and blue (0-255 each). There are much fewer than 256x256x256 entries in the colour table. I would like to be able to physically shrink this image by a factor of 2 or 4. I do not have any information about the original image except the pixel values and locations, i.e. I have no access to the data prior to scan conversion. Can anyone tell me how I can calculate the colours of the new pixels? How do I use the red, green, and blue values of the surrounding pixels to get red, green, and blue values for the pixels in the new image? I put this problem on the net a week or so ago, and while I did recieve a number of replies, I suspect that either I had not stated the problem clearly enough (although I am grateful to the people who took the time to reply), or that I don't have the necessary background knowledge to be able to use the information (I'm not a graphics wizard!). I hope that by restating the problem in this way, I will receive equally good response (surely there MUST be someone who has done this before!). As usual, thanks in advance for any help that you may be able to give. RHP