This instructable explains how to make a monochrome camera using an Omnivision OV7670 image sensor, an Arduino microcontroller, a few jumper wires, and Processing 3 software.
Experimental software for obtaining a color image is also presented.
Press the c key to capture a 640*480 pixel image … press the s key to save the image to file. Successive images are sequentially numbered should you wish to create a short time-lapse movie.
The camera is not fast (each scan takes 6.4 seconds) and is only suitable for use in fixed lighting.
The cost, excluding your Arduino and PC, is less than a cup of coffee.

Images

The component parts, without jumper wiring, are shown in the opening photo.
The second photo is a screen-shot showing the Arduino camera software and the Processing 3 frame-grabber. The inset shows how the camera is connected.
The video demonstrates the camera in action. When the c capture key is pressed there is a brief flash followed by a burst of activity as the image is scanned. The image automatically appears in the display window once the scan is complete. The images are then seen to appear in the Processing folder following each press of the s key. The video concludes by cycling rapidly through each of the three saved images.”

Link