Two simultaneous camera capture at 720p resolution, encode and stream with i.MX6 Dual

[DipenPatel1z]

Dear Support,

Is it possible to capture 2 simultaneous 1280x720p stream from two cameras on i.MX6 Dual/Quad?

My goal is simultaneous capture from two camera at 1280x720p resolution and perform H.264 encoding and stream or store.

Appreciate your earliest response.

Regards,

Dipen Patel

[igorpadykov · Accepted solution]

Hi Dipen,

yes, this is possible, however it may depend on desired fps (framerate).

CSI performance is given in sect.37.1.2.1.1 "Camera Ports"

i.MX6DQ Reference Manual (rev.1  4/2013)

http://cache.freescale.com/files/32bit/doc/ref_manual/IMX6DQRM.pdf

"For parallel interface, the maximum speed of the interface is 240Mhz. The required

operating frequency of the interface is calculated in the following way:

F = FH * FW * FPS * BI * DF

Where

• FH = frame height (in pixels)

• FW = Frame width (in pixels)

• fps = frame rate (frames per second)

• BI = typically 35% overhead, should be assumed as 1.35. The actual blanking

intervals are a parameter of the attached device.

• DF = data format, defines the number of cycles needed to send a single pixel."

For two two camera at 1280x720p@30fps it would require about 60MHz (assume 1 cycle/pixel).

H264 encode 720p@30fps two instances are possible with i.MX6DQ, please check p.31

presentation below

http://cache.freescale.com/files/training/doc/ftf/2014/FTF-CON-F0223.pdf

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[DipenPatel1z]

Hi Chipexpert,

Thank you for quick response and precise information.

So I can capture two camera streams of 720P@60fps (~166MHz).

But encode will be limited to 720P@30fps for two instances. Please confirm.

Regards,

Dipen Patel

[yangthomas]

Do you solve it?

[igorpadykov]

Hi Dipen,

yes confirm.

Best regards

chip