About ISP histogram data

Please provide the following info (check/uncheck the boxes after creating this topic):
Software Version
DRIVE OS Linux 5.2.6
DRIVE OS Linux 5.2.0
DRIVE OS Linux 5.2.0 and DriveWorks 3.5
NVIDIA DRIVE™ Software 10.0 (Linux)
NVIDIA DRIVE™ Software 9.0 (Linux)
other DRIVE OS version
other

Target Operating System
Linux
QNX
other

Hardware Platform
NVIDIA DRIVE™ AGX Xavier DevKit (E3550)
NVIDIA DRIVE™ AGX Pegasus DevKit (E3550)
other

SDK Manager Version
1.6.1.8175
1.6.0.8170
other

Host Machine Version
native Ubuntu 18.04
other

If I call GetImageData on a ISP output buffer, I will get an nvsipl::INvSIPLClient::ImageMetaData object container fields of “ISPHistogramxxx”.
Are those ISP histogram data generated by ISP or CPU?
Is there also histogram data for the ISP input (captured RAW image buffer)? who generates it?
If we don’t need that histogram data, is there a way to reduce memory bandwidth usage by not generating those histogram data?

Hi @leqiang.wang,
Histogram statistics data is generated by ISP. It is provided only with the ISP output buffer.

Histogram statistics are needed to compute the new ISP settings to process the frame in ISP. It can’t be disabled. Memory bandwidth usage due to the ISP statistics is insignificant compared to the usage from actual frames.
Thanks.

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For ISP output buffer which is in RGB format - would there there be histogram bins for each R, G and B plane ? Could size of histogram bins be contolled ? Can we have bins covering a pixel value range as opposed to bin per pixel ?