Abstract: The invention relates to pixel insertion on optical scanners. The invention increases the efficiency of video buffer in optical scanners and improves the speed of I/O device by locating the position of interpolation device in front of video buffer which is for temporarily storing image data and outputting the image data. Immediately after the video buffer is an input buffer which is for receiving the output of the video buffer. The input buffer provides an interface for video buffer and the interpolation device. The function of the interpolation device is for inserting pixels into the original pixels to increase the resolution of the image. When the host machine is requesting image data, an output buffer delivers the image data in the interpolation device to an I/O device for the host machine to read.