Best way to get intensity values of all visible pixels in a tiled layer

[s-n-i]

I am loading a Zarr pyramid, which creates a MultiscaleImageLayer. I would like to get the intensity values of all pixels within the viewport. I would like to use these intensity values to create a histogram.

Inside the draw() method of a deck.gl extension, this.props.channelData.data is available. However, it gives intensities for a whole tile.

[ilan-gold]

Yes, that's probably how it's going to work on some level no matter what you do. You will have to get all of the data of all of the tiles in the viewport. What did you have in mind besides that? To do this you can use a click handler or the like for the DeckGL component and then iterate over the layers visible in the current viewport.

[s-n-i]

Because this.props.channelData.data gives intensity values for whole tiles, this data also includes values for pixels that are offscreen. I was wondering if it is possible to get pixel intensity values from viv with these offscreen pixels already discarded. (If not, I could compute a bounding box based on viewport and exclude the offscreen pixels.)

[ilan-gold]

So yea, that's what you'll do. We don't provide that at the moment. If you come up with something, feel free to post here so other can benefit!