Log Message:
GraphicsMagick: Update to 1.3.34

1.3.34 (December 24, 2019)
==========================

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.

API Updates:

* None

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.