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I need help choosing a microcontroller for a project I'm doing.

This microcontroller needs to do the following:

1) Interface with a low resolution camera, obtain video feed from it, compress it and send it a wireless transmitter.

2) Obtain analogue data from 4-5 sensors and use that information to drive motors through PWM.

3) Obtain control data from a wireless receiver and use it to control 1-2 motors.

I am totally new to this stuff and I have no idea where to look. Basically I have no idea how to relate the specifications of a microcontroller to my specific needs. What microcontroller would suit my needs?

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  • \$\begingroup\$ The Raspberry Pi camera module is just becoming available, which might suit you. Otherwise, you're best off getting a separate wireless video solution. \$\endgroup\$ – pjc50 Mar 6 '13 at 15:48
  • \$\begingroup\$ Take a look at the TI DaVinci product lineup for video-specific ICs. \$\endgroup\$ – spearson Mar 6 '13 at 19:26
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Your bottleneck in term of processing power will be the live video processing and real time compression. Video compression done in software takes A LOT of computing time.

Simple evaluation:

you use a low res VGA sensor : 640 x 480 pixels black and white.

you have 640 x 480 = 307200 pixels.

you didn't specify the framerate. But let's decide 25 fps for the computation.

Now you have to process 307200 * 25 = 7.68 Megapixel/sec ! or 0.13us per pixel.

Imagine that you have a high-end ARM cortex-M3 microcontroller at 100 MIPS. or 0.01 us/cycle.

Then you have 0.13us / 0.01 = 13 single instructions available per pixel !

This assumes that you CPU is doing nothing else. Which is not your case. Thus your compression algorithm has to be very simple. Or you should find a chip that is able to do this for you in hardware or reduce a lot the frame rate.

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Blup1980's analysis is correct for raw frames. What I suggest is that you obtain a camera with integrated compression that will give you JPEG images, which you can read and transfer quickly using DMAs inside the processor.

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  • \$\begingroup\$ Do you know such camera. I also need similar project. Thanks \$\endgroup\$ – Arjun Jul 31 '15 at 8:08

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