Build histogram data

Submitted by ju2pom on

Hi,

I didn't find anything about histogram in the documentation, is there a way to build such data with LibRaw ?

Thanks.

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Histogram is built during

Submitted by lexa on

Histogram is built during postprocessing stage if auto-exposure is used.

Raw data are accessible after LibRaw::unpack() call, so histogram calculation is trivial single loop over all pixels.

-- Alex Tutubalin @LibRaw LLC

Thanks for the answer, is

Submitted by ju2pom on

Thanks for the answer, is there any api to get a sub-sampled version of the image data buffer because I guess it should be enough to calculate an histogram.

raw data are stored into

Submitted by lexa on

raw data are stored into imgdata.rawdata.raw_image[] array, available for both read and write.

This 'API' allows easy sampling with any stride, if you need sampled data.

-- Alex Tutubalin @LibRaw LLC