Let me ask my question a different way...

Here's what I need to do, can someone tell me what I should use:

I need to capture a digital image (med - high res color), and send that image to a remote computer via modem. I know I could do this with a laptop and other devices, but I need to do it relatively low cost using an single board computer.

Any suggestions, much appreciated.

Thanks JS

Reply to
Junior Sanders
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To provide the best answer to your question, we'll need to know a few more things.

  1. Saying medium to high res color isn't nearly enough information. What are the dimensions (horizontal, vertical, bits-per-pixel) and frames per second? How are the images being captured and how are they being presented to the system? Is the capturing device stationary or in motion? How much preprocessing will the system be expected to perform?
  2. Saying that your device will send images to a remote computer via modem is also insufficient. At how many bits-per-second can the modems communicate, will they be synchronous or asynchronous, always connected or not? These parameters will give you a rough esitmate of the bandwidth you have available. This in turn will tell you, again roughly, how long it will take to transmit a single image. If the time is inadequate, can you compress the image to reduce transmit time? Do you plan to send images as they are acquired or batch them up for mass transmittal? Will the images need to be time-tagged?
  3. You've said nothing about environmental conditions. The requirements for a rocket-mounted image capture system are quite a bit different from those of a stationary hallway monitoring system. What are the ranges of temperature, pressure & humidity to which your system may be subjected? How much power is available to your system (and in what form)? Is the shape of the system an issue?
  4. What is your budget and is the system intended to be a one-time project or a production unit? What is the intended lifespan of the system? What MTBF is acceptable?

Answering these questions in greater detail will help you decide how much processing power, memory & mass storage (if any) will be required. It will help you determine what systems, if any, meet your operational requirements.

I appreciate that you may not want to be too specific about the details of your project, but the more information you can share, the more help any answers here are likely to be.

Let me speculate, given your email address, and say that you are looking for a system intended for use inside a manufacturing shop of some sort. Cleanliness will probably be a big issue there - the cleanliness of the power getting to your system (shop power is often spikey), the cleanliness of the signal between the modems and the cleanliness of the air (can you imagine what metallic dust could do if it got inside your computer?) If this is meant to be part of a quality & uniformity inspection you'll need real-time transmittal of images. This suggests greater need for processing power (because they'll need to be packaged and possibly compressed for rapid transmittal) and lesser need for mass storage (because once sent, the images can be forgotten.)

good luck

Joe Power

Reply to
Joseph Power

Forget about JackRabbit, microcontroller and USB host/bridge adaptor. None of them give you the resources and low-level access you need. I am running a 233MHz Geode GX1 (approx 88 BogusMIPs) with 128M SDRAM for an USB web-cam. I am getting 2 to 3 frames (approx. 300x200) per second without doing anything else.

You need a fast processor to grab the video frames and lock them in RAM. Otherwise, you will be losing frames or mixing data from adjacent frames. You also need to compress the raw data into jpeg or mpeg. The expensive webcams compress the images for you. The cheaper ones don't.

On a 900 MHz Celeron with 512M SDRAM, I got about 15 fps. USB is the bottle neck here.

You probably need something in-between, perhaps a 500 MHz CPU. Beyond that, your CPU is just waiting for the USB.

Reply to
Linnix

Ok, let me try to be more specific. The environment will be outdoors. I can handle this with an enclosure. It will have to run off battery since there will be no other power available. The device will only have to take 1 picture and transmit it about every 5 or 10 minutes, so the connection speed and image size is not that big of an issue. The image will need to be a jpeg similar to that of a 3 megapixel digital camera. The device will not have a permanent connection to the remote computer, it will dial up to the remote computer each time a picture is taken. Budget is still in the air, I will be producing more than one of these, so I would like to stay as low cost as possible.

Reply to
Junior Sanders

Run off battery for how long? IOW, how often do you plan to go out there and exchange the battery? Are you aware how hard it is to make an enclosure that is weather-proof, yet still accessible enough to allow for regular exchanges of a battery?

I would advise to re-think that decision. An analog modem takes on the order of a minute just to dial and set up a connection. Doing that every 5 minutes is quite a waste of time, and possibly also of money, since you won't be transmitting any payload data during that time. On the other hand: if you have a connection to a telephone line, how come you don't have a connection to a power line?

For most other purposes, you've just described a GSM/GPRS cell-phone equipped with a camera. Now all you need is a Java program that tells it to take a picture and send it, every couple of minutes. And somebody rich enough to pay the GPRS service fees for all that.

--
Hans-Bernhard Broeker (broeker@physik.rwth-aachen.de)
Even if all the snow were burnt, ashes would remain.
Reply to
Hans-Bernhard Broeker

Look at

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for a module which will give a JPEG image over a serial link. To send it over a modem a small 8 bit micro will handle this.

Regards Anton Erasmus

Reply to
Anton Erasmus

Well, that would elimate all the webcams and most of the low end digital cameras. I assume that you want a computer controlled digital camera, not just downloading images. Only a few high end digital camera would do so, perhaps two to three hundred dollars each. Have you selected the camera? The camera might be more important than the SBC. Another consideration is: Is your target location secured enough to put in a three hundred dollar camera?

Reply to
Linnix

Round Solutions have a GSM modem that has a digital camera interface, the GM-862-PCS. They sell the camera, connector and GSM/GPRS modem for about EU 115. Alternately, they have a kit for evaluation of the camera for EU 275

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Reply to
dmm

I hope he meant auto battery, perhaps with a solar charger. If you need

5 Watts (such as ours: lower power CPU & Compact Flash Drives), you need at least a 15 Watts solar charger (including overnight stand-by). The newest solar panels can probably do it in three to four square foot.

Since it is unlikely to be a digital telephone loop, 33K is the max. and takes several miniutes for a typical jpeg image anyway.

Except that he is not just taking about tiny camera phone quality (160x140); not just cheap webcam quality (320x280); not just good webcam quality (640x480); not just low-end camera quality (800x600); but 3M pixels high-end camera quality (1200x1000). It is possible to build such super camera phone, but we are taking about hundreds, perhaps thousand dollars each.

Reply to
Linnix

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