move whatsnew to gh-pages
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whats-new.md
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---
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title: What's new in 8.11
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---
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libvips 8.11 is almost now out, so here's a quick overview of what's new. Check
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the [ChangeLog](https://github.com/libvips/libvips/blob/master/ChangeLog)
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if you need more details.
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Credit to Zeranoe, DarthSim, Projkt-James, afontenot, 781545872, erdmann,
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kleisauke and others for their great work on this release.
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[Lunaphore](https://www.lunaphore.ch/) kindly sponsored the development of
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the new JPEG2000 features, see below.
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# Experimental JPEG-XL support
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We've added perimental support for[JPEG-XL](https://jpeg.org/jpegxl/).
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This is a new iteration of the JPEG standard,
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currently in development. The Chrome web browser supports it
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behind a flag, and it looks like it might be enabled by default this autumn
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in Chrome 89.
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There have been several attempts to replace JPEG with something better in the
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last few years. HEIC is perhaps the best known: it can compress files to
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about half the size of comparable JPEGs and supports a range of useful
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features like animations, transparency and lossless
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compression. Unfortunately, it has some patent issues which may limit its
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usefulness.
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AVIF is rather like HEIC, but has no patents attached to it. Sadly the
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available load and save libraries are extremely slow.
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JPEG-XL looks like it might avoid all these problems: it offers the same great
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compression and useful features as HEIC and AVIF, but has no problems with
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patents, and is fast enough for practical use.
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I made a sample image. You'll need to zoom in to check details:
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Compression and decompression is quite a bit quicker than HEIC:
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```
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$ time vips copy astronauts.png x.jxl
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real 0m0.218s
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user 0m0.291s
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sys 0m0.204s
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$ time vips copy astronauts.png x.heic
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real 0m0.413s
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user 0m1.273s
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sys 0m0.048s
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```
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JPEG-XL is still a little immature, so it's not enabled by default in
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libvips 8.11. Hopefully the missing features (metadata, progressive encode
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and decode, animation, etc.) will arrive soon, and the remaining bugs will
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be squeezed out.
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# Thread recycling
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We've revamped the libvips threading system.
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The new implementation uses a [GLib thread
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pool](https://developer.gnome.org/glib/stable/glib-Thread-Pools.html)
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to provide a single set of threads for the whole of libvips. This means
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threads get reused rather then being constantly created and destroyed.
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This was originally intended for WebAssembly but it turned out to be useful
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for native environments as well. Relative speed-ups are varying between ~4%
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and ~15% compared to the previous implementation. Especially for short-lived
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pipelines and long-running processes, a performance improvement can be observed.
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# Loadable modules for some dependencies
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libvips now supports building OpenSlide, libheif, Poppler and libMagick
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as dynamically loadable modules. This makes it easier for distributions to
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provide separate (optional) packages for these dependencies, making the core
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package much slimmer and thus reducing the attack surface. Distributing
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separate packages could also help to comply with GPL licensing (“mere
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aggregation” clause) or patent-encumbered software.
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[GModule](https://developer.gnome.org/glib/stable/glib-Dynamic-Loading-of-Modules.html)
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is used to accomplish this in a portable way. We already had a simple plugin
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system based on this, but the build part was not yet implemented.
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These loadable modules are built automatically when GModule is supported,
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which should be at least Linux, Windows and macOS. It can be disabled by
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passing `--disable-modules` while configuring libvips.
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# Full-colour text rendering
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The libvips `text` operator was designed a while ago, when fonts were still
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black and white. It outputs a one-band mask image which you then process with
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the other libvips operations to do things like rendering text on an image.
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Many fonts, especially emoji fonts, now have full-colour SVG characters.
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There's a new `rgba` flag to `text` to enable colour rendering. For example:
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```
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$ vips text x.png "😀<span foreground='red'>red</span><span background='cyan'>blue</span>" --dpi 300 --rgba
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```
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Makes this:
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You can then use `composite` to render these text RGBA images on to another
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image.
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# JPEG2000 support
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Thanks to generous sponsorship from Lunaphore, we've added support for the
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(now rather elderly) JPEG2000 format.
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The `jp2kload` and `jp2ksave` operations support all the file format
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features: shrink-on-load, 8-, 16- and 32-bit data, any number of
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image bands, tiled images, YCC colourspace, lossless compression, and
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optional chroma subsampling. The lossy compression profile (controlled
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by a `Q` parameter) is derived from the [British Museum's JPEG2000
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recommendations](https://purl.pt/24107/1/iPres2013_PDF/An%20Analysis%20of%20Contemporary%20JPEG2000%20Codecs%20for%20Image%20Format%20Migration.pdf).
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We've also added support for JPEG2000 as a codec for TIFF load and save. This
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means you can now directly load and save some popular slide image formats.
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This should be useful for people in the medical imaging community.
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It's very easy to use -- for example:
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```
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$ vips copy k2.jpg x.tif[compression=jp2k,Q=90,tile]
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$ vips copy k2.jpg x.tif[compression=jp2k,lossless]
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```
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# C++ API improments
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We've spent some time improving the C++ API.
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We now use [doxygen](https://www.doxygen.nl) to generate C++ API docs
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automatically, and we've written a set of API comments. Hopefully the [new
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documentation](link-to-cpp-docs) should be a big improvement.
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There are a couple of functional improvements too. There's support for
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`VipsInterpolate`, `guint64` and a new constructor,
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`VImage::new_from_memory_steal`, which can save a copy operation.
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# Minor improvements
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- The `perlin`, `worley` and `gaussnoise` operators have a new `seed`
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parameter to set the seed for their random number generator.
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- The `rank` operator has a new path for large windows on 8-bit images. It can
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be up to 20 times faster in some cases.
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- Image histograms on large images now use `double` values. Previously,
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we were limited to images with under 2^32 pixels.
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- There's a new `black_point_compensation` for colour operations involving
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ICC profiles, and detection of bad profiles and fallback to default
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profiles is much better.
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- The loaders and savers for PDFium, OpenSlide, vips, NIfTI, and FITS have
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been moved to the new libvips IO framework.
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- `vipsthumbnail` can now load and save to and from stdin and stdout.
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- PNG save selects between 8- and 16-bit output more intelligently, and
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supports background colour as metadata.
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- We've switched GIF load to the excellent libnsgif library, and libvips
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embeds the library code.
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- `tiffsave` can write premultipled alpha.
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- PDFium support has been revised. It should now build very simply, and ought
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to be much faster in threaded applications.
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- We've fixed a range of reference leaks in the mosaicing package, and we
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now run the leak checker as part of CI.
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As usual,
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the [ChangeLog](https://github.com/libvips/libvips/blob/master/ChangeLog)
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has more details, if you're interested.
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