Go Down

Topic: Transferring CMOS Camera image to handheld device (Read 757 times) previous topic - next topic

Hello,

I've been reading lots of posts of users who wanted to process an image from a CMOS camera module in arduino and it seems that speed is a limiting factor.
For my project I need a video from my robots camera with a decent framerate on the handheld remote control. As my robot is under water,  the video signal has to be brought to surface via cable.

I am planning for the use of two arduinos, one in the robot and one on a buoy which are communicating via cable. The buoy has a WiFi module attached so that I can connect a laptop or another wifi-enabled device and send commands to the robot and receive the image from the camera.

If i get a camera module from which I can read a JPEG image in QVGA resolution, how would you estimate the maximum possible framerate to receive via WiFi?
I imagine as the compression is done by the camera, there will be no problem with the avr's speed, more with the bus speed.

If this is not possible, the only other chance I have is to drop the WiFi part and the buoy and control the robot directly via cable. With this, I can send back an analog video signal directly from the camera to a GLCD in the remote.

By the way, using an S-FTP ethernet cable, can I count with the same cable lengths as specified in the Cat.5e standard?

Thanks for your comments

Robert

AWOL

Quote
process an image from a CMOS camera module in arduino and it seems that speed is a limiting factor.

I'd say memory (and lack thereof) was the limiting factor
"Pete, it's a fool looks for logic in the chambers of the human heart." Ulysses Everett McGill.
Do not send technical questions via personal messaging - they will be ignored.

PaulS

Quote
If i get a camera module from which I can read a JPEG image in QVGA resolution, how would you estimate the maximum possible framerate to receive via WiFi?

Connect the camera to the PC. Download a few images. Compute the average size in bytes.

Divide the number of bytes in the image by the baud rate that the two Arduinos are communicating at (which is in bits per second; 10 bits get sent to transfer one byte).

At 115200, 11,502 bytes per second can be sent. If the average picture size is 30000 bytes, it will take nearly 3 seconds to transfer one image.

This all assumes that the camera will dole out the image in small enough parts so that the Arduino does not need to store the hole image.

Typical video has a frame rate between 15 and 30 frames per second. At 1/3 of a frame per second, your video will be very choppy.

bilbo

#3
Oct 27, 2011, 04:16 am Last Edit: Oct 27, 2011, 04:20 am by bilbo Reason: 1
Why not use the arduino for control and just use a regular IP camera for the video? You can probably find ones used for security or monitoring for pretty cheap: http://www.tigerdirect.com/applications/searchtools/item-details.asp?EdpNo=6480848&SRCCODE=GOOGLEBASE&cm_mmc_o=VRqCjC7BBTkwCjCECjCE
Or even this if you can use wired (or have a wifi-ethernet adapter) http://www.amazon.com/Internet-Camera-640X480-Motion-Detection/dp/B002Y4V64E

Obviously there are many better, higher quality cameras, but these were the cheapest I could find.
Alice asked the Chesire Cat, who was sitting in a tree, "What road do I take?"
The cat asked, "Where do you want to go?"
"I don't know," Ali

Go Up