Lets assume this is a 24 bit .bmp image. I estimate that the size would be 3.9 MB. JPEG uses some pretty amazing compression techniques and can reduce files of that resolution down to less than one megabyte without sacrificing much quality.
1.3 megapixels is referring to all of the pixels in the image, not to just one line of pixels. 1024x768 is is roughly 0.78 mp.
1.3 megapixels is referring to all of the pixels in the image, not to just one line of pixels. 1024x768 is is roughly 0.78 mp.