On Thu, 2 Jan 2025 06:49:19 GMT, Jeremy <d...@openjdk.org> wrote: >> This adds support for parsing thumbnails in an APP1 Exif marker. >> >> This builds on an unfinished proposal by Brian Burkhalter (around 2016). In >> that previous work the only additional meta info he parsed was the image >> creation time; this PR similarly includes the same property. (I can't speak >> to why he included that property, but it looks like he has a lot of >> experience with ImageIO so I trust his judgment.) >> >> The test addresses the original images attached to the ticket plus a few >> extra images I found on my computer that include unusual properties. >> (Possibly those images are malformed, but if they exist in the wild and >> other platforms support them then I'd prefer to support them too.) > > Jeremy has updated the pull request incrementally with one additional commit > since the last revision: > > 8160327: fixing typo so `thumbnailPos` can be zero > > The `thumbnailLength` cannot be zero, but the position can be.
> In that previous work the only additional meta info he parsed was the image > creation time; this PR similarly includes the same property. (I can't speak > to why he included that property [...]. Note that the `DateTime` value extracted by `ExifMarkerSegment.getImageCreationTime` is that of the primary image, not the thumbnail. This is included to support the `ImageCreationTime` element of the Image I/O Standard Metadata Format Specification `javax_imageio_1.0`. For reference see the [Exif 3.0 specification](https://iptc.org/news/exif-3-0-released-featuring-utf-8-support), although the code from 2016 was based on Exif 2.x. The sections most pertinent to thumbnails are: - 4.5.8 Basic Structure of Thumbnail Data - 4.6.9.2 Thumbnail (1st IFD) Support Levels >From section 4.6.9.2 in particular, there does not appear to be any >thumbnail-specific metadata worth extracting. ------------- PR Comment: https://git.openjdk.org/jdk/pull/22898#issuecomment-2659934595 PR Comment: https://git.openjdk.org/jdk/pull/22898#issuecomment-2659938631
