[Done] Range adjustement by band

[emmanuelmathot]

Today, titiler API allows to rescale values from a min and max for all the bands values. Would it be possible to submit an array of ranges corresponding to each bands selected to make the RGB?
something like

assets=swir22,nir,red&rescale=[[0,5000],[0.7000],[0,10000]]

[vincentsarago]

It's not document this is already possible thanks to rio/tiler
If you pass something like
rescale=1,100,1,1000,1,2555 rio-tiler will split the array for each band (I think)

This is not a great way to define it
I would prefer something like
rescale="1,1000"&rescale="1,100"&rescale="1,255" which seems a better way to pass multiple parameters 🤷‍♂️

[emmanuelmathot]

Great! Thank you for the answer. So I understand we should test with rescale=1,100,1,1000,1,2555 in the current implementation and it should work.

[emmanuelmathot]

I confirm it works! Thx @vincentsarago

[vincentsarago]

FYI https://github.com/cogeotiff/rio-tiler/blob/6c8da5e88ca562205998fae73aa42a0e9a0014b5/rio_tiler/models.py#L218-L228 is where the magic happens

[vincentsarago]

@emmanuelmathot FYI this is going to change in next titiler version per #319

As I mentioned in #304 (comment) we are going to move to rescale=1,1000&rescale=1,100&rescale=1,255 which seems to be a better way to define multiple values.

[emmanuelmathot]

Thank you for the heads up. Is the same logic applicable for nodata param?

[vincentsarago]

nodata is a unique value!

The other multiple parameter is bidx which is provided via coma (,) delimited sting (e.g: "1,2,3"). We could switch to bidx=1&bidx=2&bidx=3 but this might impact much more people so I'll need to first start the conversation before switching this