How to find and decode a specific image in a multi-image TIFF file?

[ronjakoi]

I need to work with TIFF files with multiple images, i.e. multiple IFDs. It looks like the Decoder struct in the tiff crate has the next_image() method, but that's not exposed by this crate's TiffDecoder.

Do I have to use the tiff crate separately, find the IFD I need and then read into an ImageBuffer manually somehow?

[fintelia]

At the moment, yes. To do the read into the ImageBuffer you'd need something like this logic.

(There are plans to improve the situation in the next major release, but that's still in progress)

[197g]

It's possible via the approach here: #2672, so very timely issue. Details of how to communicate the relation of the images in the sequence are still in progress and probably be solved afterwards but you'll get the (supported) image data. What's curious is that this decoder unlike the other instances could have intermittent errors that resolve by iterating to the next image, if one IFD has invalid color types or heterogeneous sample depths for instance.