Task #13106 (new)
Opened 8 years ago
Last modified 8 years ago
TiffReader: Does not handle YCbCr conversion
Reported by: | rleigh | Owned by: | |
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Priority: | minor | Milestone: | Unscheduled |
Component: | Bio-Formats | Version: | BIo-Formats-5.1.5 |
Keywords: | TiffReader YCbCr, external | Cc: | stephane.dallongeville@… |
Resources: | n.a. | Referenced By: | n.a. |
References: | n.a. | Remaining Time: | n.a. |
Sprint: | n.a. |
Description
http://lists.openmicroscopy.org.uk/pipermail/ome-users/2015-November/005733.html
This contains a sample TIFF with a YCbCr PhotometricInterpretation?. Bio-Formats seems to treat it as plain RGB, which leads to downstream clients such as the ImageJ importer and ImageInfo? displaying garbage since they treat it as RGB.
Examples of how it should display are in
http://lists.openmicroscopy.org.uk/pipermail/ome-users/2015-November/005736.html as well as the other earlier messages in the thread.
Not sure the problem is necessarily in TiffReader?; the model has no concept of PhotometricInterpretation?--maybe we need to add it? If TiffReader? should not convert the data to RGB (and I can see there are good reasons for leaving it untouched), where should this be handled?
Change History (1)
comment:1 Changed 8 years ago by mlinkert
- Keywords external added
- Owner mlinkert deleted
It's not entirely true that YCbCr is not supported - plenty of other TIFF files with YCbCr photometric interpretations are read correctly. The problem is this line: https://github.com/openmicroscopy/bioformats/blob/develop/components/formats-bsd/src/loci/formats/tiff/TiffParser.java#L733
...which seems to enable YCbCr correction, when it's actually not necessary (setting options.ycbcr to false results in the same image as shown by ImageMagick?). Worst case, the TIFF reader may need to check the software tag and disable YCbCr correction if NDP.scan is found. Storing PhotometricInterpretation? in the model should definitely not be a prerequisite here.