Memory for image processing

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Memory for image processing

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Jamo
Contributor I

Hi,

 

I am still new at choosing appropriate processors. I am looking at a 32bit processor that can do the function below:

 

 This processing function is to receive a JPG image of around 100KB from one ethernet port, shrink the image to 5KB and send it quicky out the other ethernet port as quickly as possible.

As this is MJPEG handling, it is a process of receiving, processing and outputing lots of these images as quickly as possible.

To achieve this function, I assume I would require some form of external memory (non permanent but fast).

My question is:

What advice is availble in the choice, size and type of memory to use?

If there are other solutions, I would be interested to understand

 

Jamo

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JWW
Contributor V

Jamo,

 

The first assumption is that you need dual independent ethernets?  Any other hardware contraints or technology that you want to avoid or prefer?

 

The MCF5445x family (superset chip in family is the MCF54455) should be capable of doing this application.

 

Key feature here is dual ethernet with internal high speed ram and dsp extensions in core (called eMAC) that can be used for some graphics routines.

 

Would be happy to provide guidance if needed.

 

-JWW

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Jamo
Contributor I

Hi JWW,

 

Thanks for that one,

 

As for my hardware restraints / preferences:

 

Specs

## Dual independant Ethernet (10/100 is fine) - Looking for something that can send a packet between ethernet ports at a speed of at least 1Mbps.

##  2 x Serial Ports

##  1 x port to talk to an SD card

##  at least 20 General Purpose IO (GPIO). Need to drive around 12LEDS

##  Sufficient processing power to perform a specific function. This processing function is to receive a JPG image of around 100KB from one ethernet port, shrink the image to 5KB and send it quicky out the other ethernet port.

## Capacity to add some memory (your advice here to acccomodate for processing function above and to hold firmware OS)

## Pricing range for processor is $40USD (assuming volumes of 50 at a time)

## Processor must be available gor at least the next 5 years

 

I have plenty of room on the PCB so there is not a space issue

Power is not an issue either

 

Thanking you,

 

Jamo

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TomE
Specialist II

 


> As for my hardware restraints / preferences:

> Specs

> ## Dual independant Ethernet

 

Are you sure? The dual ethernets may cause more trouble then they're worth. They should ramp up the network configuration problems by a factor of a few hundred and makes the required network support on that box a lot more complicated.


The whole POINT of networking is to save us from the tyranny of the wires. It doesn't matter where the services are on the network, we can link ports on programs with each other nomatter where they're running.

 

So a good "network application" should run with the picture source (presumably a camera), picture processor (this thing your building) and the "picture sink" on the same machine, different machines or in different countries. It shouldn't matter. If it DOES matter then something is wrong with the design and will cause problems.


So in that case,the simplest interconnection has the three things connecting to each other via an Ethernet hub or switch, and in that case the "picture processor" doesn't need two ethernet ports.

 

The Camera sends to a TCP port on the processor which is connected to the "input" side of the compression program. The "output" side connects via a different TCP port to wherever the output is going.

 

That makes the hardware cheaper, gives you a wider choice of parts and makes the programming a LOT simpler .You'll have to run something like Linux on it to support two Ethernet ports, because you're going to be "dual-hosting" to be able to send and receive packets on the right cables. It'll also mean you'll need the cables to be on separately configured networks, which means it won't be able to "plug and play" with DHCP.

 

If the camera expects DHCP to configure itself and get an IP address, then your box is going to have to run a managed DHCP server on that port, configured differently (so it doesn't clash) to the DHCP-configured port on the other side.

 

If you're going to need Linux in there to handle the networking you're going to need a LOT of RAM just for the OS and network stack, and mass storage, file system, a way to load it (USB sticks or SD cards) and so on.

 

If it only needs a single network port then it can run a very cut down OS and network stack and could fit in a part with on-chip FLASH.

 

I'd suggest you implement your "application" in C or C++ on a PC first and find out how much RAM in needs. That's going to be your limiting factor.

 

 

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Jamo
Contributor I

Oh- I would like to re-comfim that the JPG processing funtion is part of digital video so to have a processor that has the must grunt is desired. I looking to conirrm if I can do this function as multiple times a second - as quickly as possible and I assume this does depend heavily on the processor.

 

(of course keeping to the budget)

 

Thanking you

 

Jamo

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JWW
Contributor V

Jamo,

 

The dual ethernet need of your product is the single feature that immediately narrows the options for you.  I say that in a good way.  As Freescale has 100s of parts that might be able to do this job if you didn't need dual ethernet.

 

Today...  And there are always new parts coming.

But for today I would look into the MCF5445x ColdFire family ('x' is one of several digits and a 5 is the superset part).

I would also look at our recently announced MPC5125 PowerA aka PowerPC based.   Also the MPC83xx (PowerA based) family has many parts with dual ethernet in your price point.

 

All of these parts probably have the processing performance you need.  The 5445x and the 5125 have very low price points for the performance and lots of example code for simple RTOS usage with networking stack.  Linux BSPs are available for all of the above, but in your application it sounds more like a closed system, so maybe a RTOS like MQX running your network stack would be more in your liking.  (forums for MQX exist on this site if you want to learn more).

 

We have CodeWarrior available for all the previously mentioned products as well. 

 

Hope this helps.

-JWW

 

 

 

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Jamo
Contributor I

Thanks for that one JJW

 

I have acontacted at least 6 of your suppliers that service the Australian market.  Of these, only 2 responded and both of them claimed "no bid".

 

The parts I were looking for were:

 

MPC8378E Freescale Chips
MCF54453  Freescale Chips

 

If they cant acces these parts easily, is there a reason for this and is there another way to acces these parsts from Australia?

Thanks Ken

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JWW
Contributor V

Jamo,

 

Would love to help.

You can send me a private message with the distributors that you contacted, as I'd like to followup on the response.  As both of the mentioned parts are available.

 

Depending on the quantity size, you could try to use Freescale's "buydirect" button.

 

I know that the 54453 parts are available for buydirect.

Just go to the product's homepage and click the shopping cart tab at the top of the page.  You can then scroll through all the options...pick the one you want and purchase online.

 

There is also a distributor link there that you can click on for more information.

 

When you say no bid...where you suggesting that the distributor told you that your order size was too small?  Or did they have zero instock inventory?

 

-JWW

 

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