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Is there any possibility to use smartphone camera modules without their smartphone? those modules are relativity cheap and provide good results, can someone explain how to do it?

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  • \$\begingroup\$ It might help to know which module you are considering. \$\endgroup\$ – Phil Frost Apr 29 '13 at 23:02
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    \$\begingroup\$ To see how an experienced engineer approaches repurposing smartphone parts, you may like Reverse Engineering the iPod Nano 6 LCD interface and followup. Leftpondians and we other lesser mortals may need the half-speed button on their video player. Mike's delivery is not exactly laid-back. \$\endgroup\$ – RedGrittyBrick Apr 30 '13 at 13:23
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Depends on the camera and how "raw" it is.

A raw CMOS sensor usually spits data out in a 16-24 bit framed parallel bus. It's the same kind of system you see on the input of HDMI transmitters or some LCD panels. There is usually also an I2C interface for controlling the sensor. Other sensors use the same thing but transmit via LVDS (this is very common with bare LCDs). If you want an overview of how a CMOS sensor actually works, wikipedia is a good place to start.

Basically you are looking at driving the sensor with a pixel clock and a few control signals to tell it when to capture and shift the pixel data out. The clock is usually on the order of at least a few dozen MHz for bare sensors (say 5MP capturing at 30 frames a second, that's 150MHz at a minimum).

Newer sensors make use of the MIPI (Mobile Industry Processor Interface) standards and implement a high speed, multi-lane differential communications link, usually CIS-1 or CIS-2. Interfacing to these cameras is very difficult without specialized hardware, as it's a communications link similar to PCI Express.

To muddy the waters even more, some sensors have image processors built in to them and you talk to the image processor rather than the sensor itself. This isn't a bad thing, but it's something you need to be aware of. The image processor does all the black level adjustment, dead pixel correction, white balance, anti-shake, bayer compensation and other fun things that make the image sensors create such nice pictures in the first place.

Without more information from you regarding what specific module you're looking at, we can't give you a straightforward answer.

Edit 1

Given that you want it small and simple, take a look at the TCM8240MD as a starting point. It's $10 on Sparkfun. It's 1.3MP, uses an 8-bit parallel bus output with the standard pixel bus signals and an I2C control interface. It'll even output JPEG data for you. You can easily connect that to a CPLD/FPGA or something like a Cypress FX2LP to give you a two-chip USB2 streaming camera.

That's just a starting point. As I said, different sensors have different interfaces and different requirements (this one does AWB and lots of other processing that a "raw-er" camera wouldn't do).

Edit 2

If you don't need the digital image data, you have lots of easier options. this is essentially the guts of a regular old analogue security camera. It all depends on what you're after.

Edit 3

This guy seems to have gotten it working. The source is in the tcm820 directory. It was found buried in the sparkfun forum for the part.

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  • \$\begingroup\$ so basically there is no simple solution or at least cost-effective solution?? i hoped to find some kind of evaluation board, something like Leopard Imaging sells for other CMOS MIPI based sensors. (these sensor cost around ~150$ while cellphone sensor costs only a few dollars) \$\endgroup\$ – Dudas Apr 30 '13 at 12:38
  • \$\begingroup\$ Again, give us some more information on the sensor or sensors you'd like to interface with. We can't give specific answers without better questions. That specific Leopard Imaging system includes the camera, image processor and is basically an entire HW eval kit. Price seems about right for what it is, but that isn't anything like what you'd asked about. \$\endgroup\$ – akohlsmith Apr 30 '13 at 12:41
  • \$\begingroup\$ I need to assemble a small,chip & high quality imaging device. Currently I'm using Xperia arc cell-phone (back-illuminated Exmor-R CMOS) as my imaging device but i thought to build a device with the CMOS sensor only with my lenses and without the entire cell-phone. so mainly whatever sensor is the easiest to interface might do the job. \$\endgroup\$ – Dudas Apr 30 '13 at 13:27
  • \$\begingroup\$ Nota bene: The TCM8240MD is not particularly easy to work with. Nobody has been able to get usable high-resolution or JPG images out of it, due to insufficient documentation. \$\endgroup\$ – mng Apr 30 '13 at 15:27
  • \$\begingroup\$ The documentation seems to match lots of standard camera register maps... Might want to look at OmniVision's docs to see what you can match up... \$\endgroup\$ – akohlsmith Apr 30 '13 at 16:15
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Yes, but you will likely need the module's data sheet to see how to interface them.

If this wasn't what you expected, you might be over your head.

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