ATmega8, video stream processing

Question

Arduino

Arduino (i.e. ATmega8 microcontroller) will handle very simple processing of a low-resolution video stream ...? If at all examples of this?

Answer 1

Let's count.
Let's say we have a video [email protected], the data stream will be 640*480*25=7.68 Mpix/s. The maximum clock frequency of the ATmega8 controller is 16MHz. That is, a little more than two clock cycles remain for processing each pixel of the image. It is unlikely that it will be possible to do something reasonable in 2 cycles. Two conclusions arise:
1) If the entire picture is processed, or the video signal is generated from scratch, then you can forget about any high resolutions. Text mode processing will work well. Here is an example of a simple atmega terminal: www.serasidis.gr/circuits/TV_terminal/Small_TV_terminal.htm
2) If a small part of the picture is processed (for example, overlaying text on an image), then this is quite real. As an example - OSD (on-screen display):garydion.com/projects/videoverlay/ True, an external clock detector (LM1881) is used here, but no one forbids you to use it either.

Answer 2

In such cases, the ATmega is not recommended. At least for the reasons that the respected Ocelot described. The ideal case for processing streams of images (or sounds) is either an FPGA or (even better) a DSP. If you use microcontrollers, then you need something similar to ARM with DMA (Direct Memory Access).

Answer 3

www.jrobot.net/Projects/AVRcam.html