# How to calculate i.MX6 IPU CSI capability.

Question asked by Satoshi Shimoda on Sep 3, 2015

Hi community,

I have a question about i.MX6 IPU CSI.

I want to know how to calculate the CSI capability by the equation in page 2818 in IMX6SDLRM Rev.2.

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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.

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If input 1080p@30 image (YUV422 over 8bit), which calculation is correct?

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Calculation A.

F = 1920 pixels * 1080 pixels * 30 fps * 1.35 * 2cycles/pixel

= 167,961,600 Hz

= 168.0 MHz (167,961,600/(1000*1000))

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Calculation B.

F = 1920 pixels * 1080 pixels * 30 fps * 1.35 * 2cycles/pixel

= 167,961,600 Hz

= 160.2MHz (167,961,600/(1024*1024))

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I think Calculation A is correct, right?

Best Regards,

Satoshi Shimoda