Special Issues:
It has been discovered that the 'ICU' library (a perhaps 30MB C++ library) which is now often a libxml2 dependendency causes huge process initialization overhead. This is noticed as unexpected slowness when GraphicsMagick utilities are used to process small to medium sized files. The time to initialize the 'ICU' library is often longer than the time that GraphicsMagick would otherwise require to read the input file, process the image, and write the output file. If the 'ICU' dependency can not be avoided, then make sure to use the modules build so there is only impact for file formats which require libxml2. Please lobby the 'ICU' library developers to change their implementation to avoid long start-up times due to merely linking with the library.
Security Fixes:
GraphicsMagick is now participating in Google's oss-fuzz project due to the contributions and assistance of Alex Gaynor. Since February 4 2018, 386 issues have been opened by oss-fuzz (some of which were benign build issues) and 376 of those issues have been resolved. The issues list is available at
https://bugs.chromium.org/p/oss-fuzz/issues/list under search term "graphicsmagick". Issues are available for anyone to view and duplicate if they have been in "Verified" status for 30 days, or if they have been in "New" status for 90 days. There are too many fixes to list here. Please consult the GraphicsMagick ChangeLog file, Mercurial repository commit log, and the oss-fuzz issues list for details.
Bug fixes:
DPS: Eliminate a memory leak.
Debug Trace: Only output text to terminate an XML format log file if XML format is active.
EXIF Parser: Detect non-terminal parsing and report an error.
EXIF Parser: Eliminate heap buffer overflows.
HuffmanDecodeImage(): Fix heap overflow in 32-bit applications.
MAT: Implement subimage/subrange support.
MVG: Address non-terminal loops, excessive run-time, thrown assertions, divide-by-zero, heap overflow, and memory leaks.
OpenModule(): Now properly case-insensitive, as it used to be.
PCX: Verify that pixel region is not negative. Assure that opacity channel is initialized to opaqueOpacity. Update DirectClass representation while PseudoClass representation is updated. Improve read performance with uncompressed PCX.
PICT: Fix heap overflow in PICT writer.
PNG: Fix validation of raw profile length.
PNG: Skip coalescing layers if there is only one layer.
PNM: Fix denial of service opportunity by limiting the length of PNM comment text.
WPG: Avoid Avoid dereferencing a null pointer.
WPG: Implement subimage/subrange support.
WPG: Improve performance when reading an embedded image.
Wand library: In MagickClearException(), destroy any existing exception info before re-initializing the exception info or else there will be a memory leak.
XPM: Rquire that image properties appear in the first 512 bytes of the XPM file header.
New Features:
Visual Studio build supports JBIG and WebP compression in TIFF format.
Feature improvements:
Compliles clean using GCC 9.
Windows Delegate Updates/Additions:
bzlib: bzip is updated to 1.0.8 release.
jbig: jbigkit is updated to 2.1 release.
lcms: lcms2 is updated to 2.9 release.
libxml: libxml2 is updated to 2.9.10 release.
png: libpng is updated to 1.6.37 release.
tiff: libtiff is updated to 4.1.0 release.
webp: libwebp is updated to the 1.0.3 release.
zlib: zlib is updated to 1.2.11 release.
TIFF: Now also supports reading JBIG-compressed TIFF, and reading/writing WebP-compressed TIFF. A number of libtiff feature options which are now commonly enabled were disabled and are now enabled by default.
Build Changes:
MinGW: Static and shared library builds were not working. Only the modules build was actually working!
Python scripts related to the build (enabled by --enable-maintainer-mode) are now compatible with Python 3.
Now supports using Google gperftools tcmalloc library for the memory allocator. This improves performance for certain repetitive work-loads and heavily-threaded algorithms.
Configure now reports the status of zstd (FaceBook Zstandard) compression in its configuration summary.
TclMagick: Address many issues mentioned by SourceForge issue #420 "TclMagick issues and patch".
Behavior Changes:
PNG: Post-processing to convert the image type in the PNG reader based on a specified magick prefix string is now disabled. This can (and should) be done after the image has been returned.
Trace Logging: The compiled-in logging default is always to stderr, which may be over-ridden using log.mgk as soon as it is loaded.
Windows Build: Search registry key HKEY_CURRENT_USER as well as HKEY_LOCAL_MACHINE when searching for Ghostscript. By following the procedure documented in SourceForge bug 615 "GhostScript installation check", this allows for local user installations without "administrator" privileges.
