CHANGELOG.md

Notable Changes in OpenSlide

Version 4.0.0, 2023-10-11

Breaking changes

• Update soname to libopenslide.so.1
• Remove all deprecated functions
• Clear openslide_read_associated_image() output buffer on error
• Remove undocumented NULL dest support in openslide_read_associated_image()
• Change GLib log domain to OpenSlide
• Convert build system to Meson (thanks, Jan Harkes)

New features

• New format: DICOM WSI (thanks, John Cupitt and Jim O'Donnell)
• Add APIs to read ICC color profiles (thanks, John)
• Add APIs to configure tile cache size and share caches between slides
• Add properties for associated image metadata
• generic-tiff: Set MPP properties if available
• philips: Set objective power property if available
• Add slidetool command-line tool which supports all OpenSlide features
• Combine all command-line tools into the same binary
• Add ICC profile to PNG images written by command-line tools
• Add self-test that doesn't require sample data (run with meson test)

Changes

• Require libtiff ≥ 4, OpenJPEG ≥ 2.1, GLib ≥ 2.56, SQLite ≥ 3.14
• Require libdicom ≥ 1.0, with build-time fallback for now
• Remove support for including openslide.h in Visual Studio < 2013
• Fail openslide_open() with a broken pixman 0.38.x
• Avoid extra buffer copy in openslide_read_region()
• Replace goto-based cleanup with g_autoptr
• Stop using deprecated GLib slice allocator
• Use internal wrappers for file I/O
• Documentation improvements

Bug fixes

• Use UTF-8 filenames on Windows
• Improve openslide-write-png performance for very large regions
• Fix assertions on JPEG decode errors when compiled with Clang
• Portability fixes (thanks, Billy Robert O'Neal III and Kleis Auke Wolthuizen)
• aperio: Set objective power property even if floating point
• hamamatsu: Fix Restart marker not found on VMS slides with multiple Z-layers
• hamamatsu: Fix integer overflow in VMS parsing (thanks, Adam Goode)
• mirax: Fix Expected 1 value error
• philips: Don't cache missing tiles
• sakura: Fix memory leak reading missing tile

Version 3.4.1, 2015-04-20

• New formats: Philips TIFF, Ventana TIFF
• Support OpenJPEG 2.1.0
• Improve performance of JPEG and JP2K decoding
• Add openslide.region[i].* properties
• Improve MATLAB compatibility
• Enable function deprecation warnings with MSVC
• Many portability fixes
• aperio: Detect OpenJPEG chroma subsampling breakage during open
• aperio: Fill in missing tiles with downsampled data
• aperio: Report MPP for slides scanned in locales with decimal comma
• hamamatsu: Support NDPI files > 4 GB
• hamamatsu: Properly detect NDPI slides produced by NDP.toolkit
• hamamatsu: Support VMS/VMU slides without a NoLayers key
• hamamatsu: Report MPP for VMS/VMU
• leica: Support slides with 2010/03/10 XML namespace
• leica: Base64-decode leica.barcode property in 2010/10/01 namespace
• sakura: Support slides with multiple focal planes
• sakura: Support slides without tile table
• ventana: Support slides with multiple focal planes
• ventana: Improve positioning of AOIs within level
• ventana: Fix failure to recognize macro image on some slides

Version 3.4.0, 2014-01-25

• Major internal restructuring
• New formats: Hamamatsu NDPI, Sakura SVSLIDE, Ventana BIF (preliminary)
• Add openslide_detect_vendor()
• Deprecate openslide_can_open() (not very useful and often misused)
• Document performance considerations for openslide_open()
• Add properties giving the bounds of the non-empty region of the slide
• leica: Support multiple main images if their levels are coplanar
• leica: Use slide size as level size
• mirax: Support PNG- and BMP-formatted slides
• mirax: Fix Expected first 0 value error opening some slides
• mirax: Fix incorrect tile placement on some slides without overlaps
• mirax: Never synthesize downsampled levels
• Add OPENSLIDE_DEBUG environment variable (OPENSLIDE_DEBUG=? for help)
• Fix some crashes in error paths
• Add tests for many error paths

Version 3.3.3, 2013-04-13

• Fix inclusion of openslide.h with MSVC
• Properly handle Aperio JP2K slides with zero-length tiles
• Support Hamamatsu slides with blank MacroImage key

Version 3.3.2, 2012-12-01

• Fix seams in MIRAX 2.2 slides (thanks, Agelos Pappas)
• Fix associated image naming in single-level Aperio slides
• Stop decoding MIRAX tiles outside requested region
• Stop decoding unneeded tiles during tile-aligned accesses
• Increase Hamamatsu VMU tile size to reduce rendering overhead
• Document performance considerations for openslide_can_open()

Version 3.3.1, 2012-10-14

• Parallelize concurrent openslide_read_region calls on an openslide_t
• Eliminate background scanning of tile headers in MIRAX
• Scan many fewer tiles during first accesses to Hamamatsu VMS
• Ignore Leica Z-planes other than 0
• Add experimental tile-size properties
• Document API thread safety

Version 3.3.0, 2012-09-08

• Support Leica SCN format (requires libtiff ≥ 4) (thanks, Agelos Pappas)
• Allow opening MIRAX 2.2 slides (though there are seams, bug #92)
• Add standardized microns-per-pixel and objective-power properties
• Add macro associated image in Trestle
• Rename layer to level throughout the API (deprecate layer functions; remove layer properties)
• Report parse errors in openslide_open() by returning an openslide_t in error state
• Deprecate openslide_get_comment()
• Add openslide_get_version()
• Improve command-line tools; add manpages
• Support building with MinGW-w64; drop CMake, MSVC, mingw32
• Add tests for many error paths

Version 3.2.6, 2012-02-23

• Support downsampled MIRAX files
• Improve performance on MIRAX slides without tile overlaps
• Fix openslide_read_region for large dimensions on layer > 0 (3.2.5 regression)
• Correct subpixel error in MIRAX tile placement
• Fix unlikely use-after-free with Hamamatsu VMU

Version 3.2.5, 2011-12-16

• Support MIRAX 1.03 files (thanks, Jan Harkes)
• Fix openslide_read_region for large dimensions
• Use subpixel precision in all backends
• Don't keep associated images in memory
• Disable quickhash-1 for TIFF files with very large top layer
• Various build fixes (thanks, Jan, Marco Feuerstein, and Mathieu Malaterre)
• Fix some unlikely memory leaks

Version 3.2.4, 2011-03-07

• Support MIRAX files that do not have non-hierarchical data (thanks, Jan Harkes)
• Fix compilation on Windows (thanks Hauke Heibel)
• Work around a bug in GKeyFile parser (thanks, Jan)

Version 3.2.3, 2010-09-09

• Support MIRAX files that use a variant format for tile positions (thanks, Hauke Heibel and Marco Feuerstein)
• Update location of website
• Add background color property, for slides that have it
• Update CMake scripts and other Windows fixes (thanks Hauke and Marco)
• Fix some test.c bugs
• Fix incorrect MIRAX drawing at certain resolutions (thanks Hauke and Marco)
• Support quickhash-1 on older systems (thanks, Jan Harkes)

Version 3.2.2, 2010-06-16

• Rework some internals of openslide_read_region
• Support negative coordinates and zero-sized dimensions in openslide_read_region
• Clarify the documentation about openslide_read_region
• Fix Windows build bug with new NGR support
• Enable untested BigTIFF support

Version 3.2.1, 2010-06-03

• Fix crashes on Windows when trying to read Hamamatsu files
• Fix jpeg 7 problems in read_from_one_jpeg
• Quiet the error handling system after the first error

Version 3.2.0, 2010-06-01

• Add experimental CMake support and fixes for building with MSVC (thanks to Hauke Heibel!)
• Enable detecting runtime errors
• Add initial Hamamatsu Nanozoomer VMU support (thanks to Steve Lamont)
• Add openslide-write-png tool

Version 3.1.1, 2010-04-27

• Fix a crash when reading an invalid VMS file
• Fix memory leaks when reading an invalid VMS file
• Accept VMS files that have more than one focal plane (non-0 planes ignored)
• Fix bug that could cause problems with libtiff 4
• Relax the required version of Microsoft.VC80.CRT

Version 3.1.0, 2010-04-01

• Enable large file access on Windows (requires Microsoft.VC80.CRT)
• Support newer Aperio files (compression 33005)
• Be more robust in reading raw TIFF tiles
• Reject invalid TIFF files earlier
• Fix many memory leaks when probing for TIFF files

Version 3.0.3, 2010-03-01

• Fix nasty artifacts in some MIRAX files (seen at some zoom levels)

Version 3.0.2, 2010-02-17

• Restore ability to build with glib 2.12, at the expense of not having "quickhash-1" in that configuration

Version 3.0.1, 2010-02-04

• Fix edge-drawing bug in TIFF backend
• Ship CHANGELOG.txt

Version 3.0.0, 2010-01-28

• Switch from GPLv2 to LGPLv2
• Reduce some unlikely memory leaks
• Support of more MIRAX files
• Improve performance of MIRAX rendering, vastly in some cases
• Reduce appearance of seams in MIRAX
• Add "quickhash-1" hash property
• Add openslide-quickhash1sum and openslide-show-properties tools
• Rework the API documentation
• Remove never-implemented prefetch functions from openslide.h (but retain with warnings in the library)
• Start attempting to figure out Trestle tile position files
• Add some defined property names to the header file

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Version 2.3.1, 2009-12-14

• Eliminate Aperio regression introduced in Version 2.3.0

Version 2.3.0, 2009-12-11

• Support for generic tiled TIFF format (for InterScope files)
• Bug fixes
• Reduction of some TIFF error messages
• Fixes for some build problems
• Deprecate prefetch functions (never implemented)

Version 2.2.1, 2009-10-23

• Fixes for thread safety problems in 2.2.0

Version 2.2.0, 2009-09-15

• Thread safety (lockless with Hamamatsu and MIRAX files)

Version 2.1.0, 2009-08-18

• Support for MIRAX mrxs

Version 2.0.0, 2009-07-16

• Support for image metadata and associated images
• Support Aperio variant
• Internally rework a lot in preparation for MIRAX
• Win32 support

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Version 1.1.1, 2009-02-25

• Remove never-functional generic JPEG 2000 support
• Switch Aperio to use the released version of OpenJPEG
• Be more robust to errors in general

Version 1.1.0, 2008-12-20

• Greatly speed up Hamamatsu with a tile cache and background scanning thread

Version 1.0.0, 2008-12-09

• Renamed to "OpenSlide"
• Multi-file Hamamatsu support
• Switch to 64-bit signed integers in public API where possible

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Version 0.5.0, 2008-10-21

• GPLv2 release
• Working Aperio support
• More work on generic JPEG 2000

Version 0.4.2, 2008-09-05

• Documentation updates
• For Aperio, remove Jasper in lieu of using OpenJPEG
• Preliminary and non-functional generic JPEG 2000 support

Version 0.4.0, 2008-03-12

• Update simple test program

Version 0.3.0, 2008-01-31

• Broken and unusably slow Aperio support

Version 0.2.0, 2008-01-19

• Using glib
• Layers are numbered instead of named
• Actual start of implementation
• Initial Trestle support
• Initial Aperio support (without tile codec)
• Initial slow and incomplete Hamamatsu support
• Initial test program
• Documentation updates

Version 0.1.0, 2007-12-06

• Unreleased, just documentation and headers (called "Wholeslide")