diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 0000000..6c6da92
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1,89 @@
+#sources
+*.c text
+*.cc text
+*.cxx text
+*.cpp text
+*.c++ text
+*.hpp text
+*.h text
+*.h++ text
+*.hh text
+
+# Compiled Object files
+*.slo binary
+*.lo binary
+*.o binary
+*.obj binary
+
+# Precompiled Headers
+*.gch binary
+*.pch binary
+
+# Compiled Dynamic libraries
+*.so binary
+*.dylib binary
+*.dll binary
+
+# Compiled Static libraries
+*.lai binary
+*.la binary
+*.a binary
+*.lib binary
+
+# Executables
+*.exe binary
+*.out binary
+*.app binary
+###############################################################################
+# Set default behavior to automatically normalize line endings.
+###############################################################################
+* text=auto
+
+###############################################################################
+# Set the merge driver for project and solution files
+#
+# Merging from the command prompt will add diff markers to the files if there
+# are conflicts (Merging from VS is not affected by the settings below, in VS
+# the diff markers are never inserted). Diff markers may cause the following
+# file extensions to fail to load in VS. An alternative would be to treat
+# these files as binary and thus will always conflict and require user
+# intervention with every merge. To do so, just comment the entries below and
+# uncomment the group further below
+###############################################################################
+
+*.sln text eol=crlf
+*.csproj text eol=crlf
+*.vbproj text eol=crlf
+*.vcxproj text eol=crlf
+*.vcproj text eol=crlf
+*.dbproj text eol=crlf
+*.fsproj text eol=crlf
+*.lsproj text eol=crlf
+*.wixproj text eol=crlf
+*.modelproj text eol=crlf
+*.sqlproj text eol=crlf
+*.wmaproj text eol=crlf
+
+*.xproj text eol=crlf
+*.props text eol=crlf
+*.filters text eol=crlf
+*.vcxitems text eol=crlf
+
+
+#*.sln merge=binary
+#*.csproj merge=binary
+#*.vbproj merge=binary
+#*.vcxproj merge=binary
+#*.vcproj merge=binary
+#*.dbproj merge=binary
+#*.fsproj merge=binary
+#*.lsproj merge=binary
+#*.wixproj merge=binary
+#*.modelproj merge=binary
+#*.sqlproj merge=binary
+#*.wwaproj merge=binary
+
+#*.xproj merge=binary
+#*.props merge=binary
+#*.filters merge=binary
+#*.vcxitems merge=binary
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..4ba92b0
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,338 @@
+## Ignore Visual Studio temporary files, build results, and
+## files generated by popular Visual Studio add-ons.
+##
+## Get latest from https://github.com/github/gitignore/blob/master/VisualStudio.gitignore
+
+# User-specific files
+*.rsuser
+*.suo
+*.user
+*.userosscache
+*.sln.docstates
+
+# User-specific files (MonoDevelop/Xamarin Studio)
+*.userprefs
+
+# Build results
+[Dd]ebug/
+[Dd]ebugPublic/
+[Rr]elease/
+[Rr]eleases/
+x64/
+x86/
+[Aa][Rr][Mm]/
+[Aa][Rr][Mm]64/
+bld/
+[Bb]in/
+[Oo]bj/
+[Ll]og/
+
+# Visual Studio 2015/2017 cache/options directory
+.vs/
+# Uncomment if you have tasks that create the project's static files in wwwroot
+#wwwroot/
+
+# Visual Studio 2017 auto generated files
+Generated\ Files/
+
+# MSTest test Results
+[Tt]est[Rr]esult*/
+[Bb]uild[Ll]og.*
+
+# NUNIT
+*.VisualState.xml
+TestResult.xml
+
+# Build Results of an ATL Project
+[Dd]ebugPS/
+[Rr]eleasePS/
+dlldata.c
+
+# Benchmark Results
+BenchmarkDotNet.Artifacts/
+
+# .NET Core
+project.lock.json
+project.fragment.lock.json
+artifacts/
+
+# StyleCop
+StyleCopReport.xml
+
+# Files built by Visual Studio
+*_i.c
+*_p.c
+*_h.h
+*.ilk
+*.meta
+*.obj
+*.iobj
+*.pch
+*.pdb
+*.ipdb
+*.pgc
+*.pgd
+*.rsp
+*.sbr
+*.tlb
+*.tli
+*.tlh
+*.tmp
+*.tmp_proj
+*_wpftmp.csproj
+*.log
+*.vspscc
+*.vssscc
+.builds
+*.pidb
+*.svclog
+*.scc
+
+# Chutzpah Test files
+_Chutzpah*
+
+# Visual C++ cache files
+ipch/
+*.aps
+*.ncb
+*.opendb
+*.opensdf
+*.sdf
+*.cachefile
+*.VC.db
+*.VC.VC.opendb
+
+# Visual Studio profiler
+*.psess
+*.vsp
+*.vspx
+*.sap
+
+# Visual Studio Trace Files
+*.e2e
+
+# TFS 2012 Local Workspace
+$tf/
+
+# Guidance Automation Toolkit
+*.gpState
+
+# ReSharper is a .NET coding add-in
+_ReSharper*/
+*.[Rr]e[Ss]harper
+*.DotSettings.user
+
+# JustCode is a .NET coding add-in
+.JustCode
+
+# TeamCity is a build add-in
+_TeamCity*
+
+# DotCover is a Code Coverage Tool
+*.dotCover
+
+# AxoCover is a Code Coverage Tool
+.axoCover/*
+!.axoCover/settings.json
+
+# Visual Studio code coverage results
+*.coverage
+*.coveragexml
+
+# NCrunch
+_NCrunch_*
+.*crunch*.local.xml
+nCrunchTemp_*
+
+# MightyMoose
+*.mm.*
+AutoTest.Net/
+
+# Web workbench (sass)
+.sass-cache/
+
+# Installshield output folder
+[Ee]xpress/
+
+# DocProject is a documentation generator add-in
+DocProject/buildhelp/
+DocProject/Help/*.HxT
+DocProject/Help/*.HxC
+DocProject/Help/*.hhc
+DocProject/Help/*.hhk
+DocProject/Help/*.hhp
+DocProject/Help/Html2
+DocProject/Help/html
+
+# Click-Once directory
+publish/
+
+# Publish Web Output
+*.[Pp]ublish.xml
+*.azurePubxml
+# Note: Comment the next line if you want to checkin your web deploy settings,
+# but database connection strings (with potential passwords) will be unencrypted
+*.pubxml
+*.publishproj
+
+# Microsoft Azure Web App publish settings. Comment the next line if you want to
+# checkin your Azure Web App publish settings, but sensitive information contained
+# in these scripts will be unencrypted
+PublishScripts/
+
+# NuGet Packages
+*.nupkg
+# The packages folder can be ignored because of Package Restore
+**/[Pp]ackages/*
+# except build/, which is used as an MSBuild target.
+!**/[Pp]ackages/build/
+# Uncomment if necessary however generally it will be regenerated when needed
+#!**/[Pp]ackages/repositories.config
+# NuGet v3's project.json files produces more ignorable files
+*.nuget.props
+*.nuget.targets
+
+# Microsoft Azure Build Output
+csx/
+*.build.csdef
+
+# Microsoft Azure Emulator
+ecf/
+rcf/
+
+# Windows Store app package directories and files
+AppPackages/
+BundleArtifacts/
+Package.StoreAssociation.xml
+_pkginfo.txt
+*.appx
+
+# Visual Studio cache files
+# files ending in .cache can be ignored
+*.[Cc]ache
+# but keep track of directories ending in .cache
+!*.[Cc]ache/
+
+# Others
+ClientBin/
+~$*
+*~
+*.dbmdl
+*.dbproj.schemaview
+*.jfm
+*.pfx
+*.publishsettings
+orleans.codegen.cs
+
+# Including strong name files can present a security risk
+# (https://github.com/github/gitignore/pull/2483#issue-259490424)
+#*.snk
+
+# Since there are multiple workflows, uncomment next line to ignore bower_components
+# (https://github.com/github/gitignore/pull/1529#issuecomment-104372622)
+#bower_components/
+# ASP.NET Core default setup: bower directory is configured as wwwroot/lib/ and bower restore is true
+**/wwwroot/lib/
+
+# RIA/Silverlight projects
+Generated_Code/
+
+# Backup & report files from converting an old project file
+# to a newer Visual Studio version. Backup files are not needed,
+# because we have git ;-)
+_UpgradeReport_Files/
+Backup*/
+UpgradeLog*.XML
+UpgradeLog*.htm
+ServiceFabricBackup/
+*.rptproj.bak
+
+# SQL Server files
+*.mdf
+*.ldf
+*.ndf
+
+# Business Intelligence projects
+*.rdl.data
+*.bim.layout
+*.bim_*.settings
+*.rptproj.rsuser
+
+# Microsoft Fakes
+FakesAssemblies/
+
+# GhostDoc plugin setting file
+*.GhostDoc.xml
+
+# Node.js Tools for Visual Studio
+.ntvs_analysis.dat
+node_modules/
+
+# Visual Studio 6 build log
+*.plg
+
+# Visual Studio 6 workspace options file
+*.opt
+
+# Visual Studio 6 auto-generated workspace file (contains which files were open etc.)
+*.vbw
+
+# Visual Studio LightSwitch build output
+**/*.HTMLClient/GeneratedArtifacts
+**/*.DesktopClient/GeneratedArtifacts
+**/*.DesktopClient/ModelManifest.xml
+**/*.Server/GeneratedArtifacts
+**/*.Server/ModelManifest.xml
+_Pvt_Extensions
+
+# Paket dependency manager
+.paket/paket.exe
+paket-files/
+
+# FAKE - F# Make
+.fake/
+
+# JetBrains Rider
+.idea/
+*.sln.iml
+
+# CodeRush personal settings
+.cr/personal
+
+# Python Tools for Visual Studio (PTVS)
+__pycache__/
+*.pyc
+
+# Cake - Uncomment if you are using it
+# tools/**
+# !tools/packages.config
+
+# Tabs Studio
+*.tss
+
+# Telerik's JustMock configuration file
+*.jmconfig
+
+# BizTalk build output
+*.btp.cs
+*.btm.cs
+*.odx.cs
+*.xsd.cs
+
+# OpenCover UI analysis results
+OpenCover/
+
+# Azure Stream Analytics local run output
+ASALocalRun/
+
+# MSBuild Binary and Structured Log
+*.binlog
+
+# NVidia Nsight GPU debugger configuration file
+*.nvuser
+
+# MFractors (Xamarin productivity tool) working folder
+.mfractor/
+
+# Local History for Visual Studio
+.localhistory/
diff --git a/CMakeLists.txt b/CMakeLists.txt
new file mode 100644
index 0000000..992774c
--- /dev/null
+++ b/CMakeLists.txt
@@ -0,0 +1,49 @@
+cmake_minimum_required(VERSION 3.16)
+
+project(libgrayworld LANGUAGES CXX)
+
+add_library(grayworld SHARED src/grayworld.cpp)
+
+target_include_directories(grayworld PRIVATE /usr/local/include/avisynth)
+
+if (NOT CMAKE_BUILD_TYPE)
+ set(CMAKE_BUILD_TYPE "Release" CACHE STRING "" FORCE)
+endif()
+
+string(TOLOWER ${CMAKE_BUILD_TYPE} build_type)
+if (build_type STREQUAL debug)
+ target_compile_definitions(grayworld PRIVATE DEBUG_BUILD)
+else (build_type STREQUAL release)
+ target_compile_definitions(grayworld PRIVATE RELEASE_BUILD)
+endif ()
+
+message(STATUS "Build type - ${CMAKE_BUILD_TYPE}")
+
+target_compile_features(grayworld PRIVATE cxx_std_17)
+
+find_package (Git)
+
+if (GIT_FOUND)
+ execute_process (COMMAND ${GIT_EXECUTABLE} describe --tags --abbrev=0
+ OUTPUT_VARIABLE ver
+ OUTPUT_STRIP_TRAILING_WHITESPACE
+ )
+ set_target_properties(grayworld PROPERTIES OUTPUT_NAME "grayworld.${ver}")
+else ()
+ message (STATUS "GIT not found")
+endif ()
+
+include(GNUInstallDirs)
+
+INSTALL(TARGETS grayworld LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}/avisynth")
+
+# uninstall target
+if(NOT TARGET uninstall)
+ configure_file(
+ "${CMAKE_CURRENT_SOURCE_DIR}/cmake_uninstall.cmake.in"
+ "${CMAKE_CURRENT_BINARY_DIR}/cmake_uninstall.cmake"
+ IMMEDIATE @ONLY)
+
+ add_custom_target(uninstall
+ COMMAND ${CMAKE_COMMAND} -P ${CMAKE_CURRENT_BINARY_DIR}/cmake_uninstall.cmake)
+endif()
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..f288702
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,674 @@
+ GNU GENERAL PUBLIC LICENSE
+ Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc.
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+ Preamble
+
+ The GNU General Public License is a free, copyleft license for
+software and other kinds of works.
+
+ The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works. By contrast,
+the GNU General Public License is intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
+software for all its users. We, the Free Software Foundation, use the
+GNU General Public License for most of our software; it applies also to
+any other work released this way by its authors. You can apply it to
+your programs, too.
+
+ When we speak of free software, we are referring to freedom, not
+price. Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+them if you wish), that you receive source code or can get it if you
+want it, that you can change the software or use pieces of it in new
+free programs, and that you know you can do these things.
+
+ To protect your rights, we need to prevent others from denying you
+these rights or asking you to surrender the rights. Therefore, you have
+certain responsibilities if you distribute copies of the software, or if
+you modify it: responsibilities to respect the freedom of others.
+
+ For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must pass on to the recipients the same
+freedoms that you received. You must make sure that they, too, receive
+or can get the source code. And you must show them these terms so they
+know their rights.
+
+ Developers that use the GNU GPL protect your rights with two steps:
+(1) assert copyright on the software, and (2) offer you this License
+giving you legal permission to copy, distribute and/or modify it.
+
+ For the developers' and authors' protection, the GPL clearly explains
+that there is no warranty for this free software. For both users' and
+authors' sake, the GPL requires that modified versions be marked as
+changed, so that their problems will not be attributed erroneously to
+authors of previous versions.
+
+ Some devices are designed to deny users access to install or run
+modified versions of the software inside them, although the manufacturer
+can do so. This is fundamentally incompatible with the aim of
+protecting users' freedom to change the software. The systematic
+pattern of such abuse occurs in the area of products for individuals to
+use, which is precisely where it is most unacceptable. Therefore, we
+have designed this version of the GPL to prohibit the practice for those
+products. If such problems arise substantially in other domains, we
+stand ready to extend this provision to those domains in future versions
+of the GPL, as needed to protect the freedom of users.
+
+ Finally, every program is threatened constantly by software patents.
+States should not allow patents to restrict development and use of
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+avoid the special danger that patents applied to a free program could
+make it effectively proprietary. To prevent this, the GPL assures that
+patents cannot be used to render the program non-free.
+
+ The precise terms and conditions for copying, distribution and
+modification follow.
+
+ TERMS AND CONDITIONS
+
+ 0. Definitions.
+
+ "This License" refers to version 3 of the GNU General Public License.
+
+ "Copyright" also means copyright-like laws that apply to other kinds of
+works, such as semiconductor masks.
+
+ "The Program" refers to any copyrightable work licensed under this
+License. Each licensee is addressed as "you". "Licensees" and
+"recipients" may be individuals or organizations.
+
+ To "modify" a work means to copy from or adapt all or part of the work
+in a fashion requiring copyright permission, other than the making of an
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+earlier work or a work "based on" the earlier work.
+
+ A "covered work" means either the unmodified Program or a work based
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+
+ To "propagate" a work means to do anything with it that, without
+permission, would make you directly or secondarily liable for
+infringement under applicable copyright law, except executing it on a
+computer or modifying a private copy. Propagation includes copying,
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+public, and in some countries other activities as well.
+
+ To "convey" a work means any kind of propagation that enables other
+parties to make or receive copies. Mere interaction with a user through
+a computer network, with no transfer of a copy, is not conveying.
+
+ An interactive user interface displays "Appropriate Legal Notices"
+to the extent that it includes a convenient and prominently visible
+feature that (1) displays an appropriate copyright notice, and (2)
+tells the user that there is no warranty for the work (except to the
+extent that warranties are provided), that licensees may convey the
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+the interface presents a list of user commands or options, such as a
+menu, a prominent item in the list meets this criterion.
+
+ 1. Source Code.
+
+ The "source code" for a work means the preferred form of the work
+for making modifications to it. "Object code" means any non-source
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+(if any) on which the executable work runs, or a compiler used to
+produce the work, or an object code interpreter used to run it.
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+linked subprograms that the work is specifically designed to require,
+such as by intimate data communication or control flow between those
+subprograms and other parts of the work.
+
+ The Corresponding Source need not include anything that users
+can regenerate automatically from other parts of the Corresponding
+Source.
+
+ The Corresponding Source for a work in source code form is that
+same work.
+
+ 2. Basic Permissions.
+
+ All rights granted under this License are granted for the term of
+copyright on the Program, and are irrevocable provided the stated
+conditions are met. This License explicitly affirms your unlimited
+permission to run the unmodified Program. The output from running a
+covered work is covered by this License only if the output, given its
+content, constitutes a covered work. This License acknowledges your
+rights of fair use or other equivalent, as provided by copyright law.
+
+ You may make, run and propagate covered works that you do not
+convey, without conditions so long as your license otherwise remains
+in force. You may convey covered works to others for the sole purpose
+of having them make modifications exclusively for you, or provide you
+with facilities for running those works, provided that you comply with
+the terms of this License in conveying all material for which you do
+not control copyright. Those thus making or running the covered works
+for you must do so exclusively on your behalf, under your direction
+and control, on terms that prohibit them from making any copies of
+your copyrighted material outside their relationship with you.
+
+ Conveying under any other circumstances is permitted solely under
+the conditions stated below. Sublicensing is not allowed; section 10
+makes it unnecessary.
+
+ 3. Protecting Users' Legal Rights From Anti-Circumvention Law.
+
+ No covered work shall be deemed part of an effective technological
+measure under any applicable law fulfilling obligations under article
+11 of the WIPO copyright treaty adopted on 20 December 1996, or
+similar laws prohibiting or restricting circumvention of such
+measures.
+
+ When you convey a covered work, you waive any legal power to forbid
+circumvention of technological measures to the extent such circumvention
+is effected by exercising rights under this License with respect to
+the covered work, and you disclaim any intention to limit operation or
+modification of the work as a means of enforcing, against the work's
+users, your or third parties' legal rights to forbid circumvention of
+technological measures.
+
+ 4. Conveying Verbatim Copies.
+
+ You may convey verbatim copies of the Program's source code as you
+receive it, in any medium, provided that you conspicuously and
+appropriately publish on each copy an appropriate copyright notice;
+keep intact all notices stating that this License and any
+non-permissive terms added in accord with section 7 apply to the code;
+keep intact all notices of the absence of any warranty; and give all
+recipients a copy of this License along with the Program.
+
+ You may charge any price or no price for each copy that you convey,
+and you may offer support or warranty protection for a fee.
+
+ 5. Conveying Modified Source Versions.
+
+ You may convey a work based on the Program, or the modifications to
+produce it from the Program, in the form of source code under the
+terms of section 4, provided that you also meet all of these conditions:
+
+ a) The work must carry prominent notices stating that you modified
+ it, and giving a relevant date.
+
+ b) The work must carry prominent notices stating that it is
+ released under this License and any conditions added under section
+ 7. This requirement modifies the requirement in section 4 to
+ "keep intact all notices".
+
+ c) You must license the entire work, as a whole, under this
+ License to anyone who comes into possession of a copy. This
+ License will therefore apply, along with any applicable section 7
+ additional terms, to the whole of the work, and all its parts,
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+ permission to license the work in any other way, but it does not
+ invalidate such permission if you have separately received it.
+
+ d) If the work has interactive user interfaces, each must display
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+ interfaces that do not display Appropriate Legal Notices, your
+ work need not make them do so.
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+works, which are not by their nature extensions of the covered work,
+and which are not combined with it such as to form a larger program,
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+used to limit the access or legal rights of the compilation's users
+beyond what the individual works permit. Inclusion of a covered work
+in an aggregate does not cause this License to apply to the other
+parts of the aggregate.
+
+ 6. Conveying Non-Source Forms.
+
+ You may convey a covered work in object code form under the terms
+of sections 4 and 5, provided that you also convey the
+machine-readable Corresponding Source under the terms of this License,
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+
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+ (including a physical distribution medium), accompanied by the
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+ customarily used for software interchange.
+
+ b) Convey the object code in, or embodied in, a physical product
+ (including a physical distribution medium), accompanied by a
+ written offer, valid for at least three years and valid for as
+ long as you offer spare parts or customer support for that product
+ model, to give anyone who possesses the object code either (1) a
+ copy of the Corresponding Source for all the software in the
+ product that is covered by this License, on a durable physical
+ medium customarily used for software interchange, for a price no
+ more than your reasonable cost of physically performing this
+ conveying of source, or (2) access to copy the
+ Corresponding Source from a network server at no charge.
+
+ c) Convey individual copies of the object code with a copy of the
+ written offer to provide the Corresponding Source. This
+ alternative is allowed only occasionally and noncommercially, and
+ only if you received the object code with such an offer, in accord
+ with subsection 6b.
+
+ d) Convey the object code by offering access from a designated
+ place (gratis or for a charge), and offer equivalent access to the
+ Corresponding Source in the same way through the same place at no
+ further charge. You need not require recipients to copy the
+ Corresponding Source along with the object code. If the place to
+ copy the object code is a network server, the Corresponding Source
+ may be on a different server (operated by you or a third party)
+ that supports equivalent copying facilities, provided you maintain
+ clear directions next to the object code saying where to find the
+ Corresponding Source. Regardless of what server hosts the
+ Corresponding Source, you remain obligated to ensure that it is
+ available for as long as needed to satisfy these requirements.
+
+ e) Convey the object code using peer-to-peer transmission, provided
+ you inform other peers where the object code and Corresponding
+ Source of the work are being offered to the general public at no
+ charge under subsection 6d.
+
+ A separable portion of the object code, whose source code is excluded
+from the Corresponding Source as a System Library, need not be
+included in conveying the object code work.
+
+ A "User Product" is either (1) a "consumer product", which means any
+tangible personal property which is normally used for personal, family,
+or household purposes, or (2) anything designed or sold for incorporation
+into a dwelling. In determining whether a product is a consumer product,
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+ When you convey a copy of a covered work, you may at your option
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+ All other non-permissive additional terms are considered "further
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+ You may not propagate or modify a covered work except as expressly
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+ Termination of your rights under this section does not terminate the
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+ 9. Acceptance Not Required for Having Copies.
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+ You are not required to accept this License in order to receive or
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+ 10. Automatic Licensing of Downstream Recipients.
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+ Each time you convey a covered work, the recipient automatically
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+ An "entity transaction" is a transaction transferring control of an
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+ You may not impose any further restrictions on the exercise of the
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+any patent claim is infringed by making, using, selling, offering for
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+
+ 11. Patents.
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+ A "contributor" is a copyright holder who authorizes use under this
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+ A contributor's "essential patent claims" are all patent claims
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+ Each contributor grants you a non-exclusive, worldwide, royalty-free
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+ In the following three paragraphs, a "patent license" is any express
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+(such as an express permission to practice a patent or covenant not to
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+available, or (2) arrange to deprive yourself of the benefit of the
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+consistent with the requirements of this License, to extend the patent
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+covered work in a country, or your recipient's use of the covered work
+in a country, would infringe one or more identifiable patents in that
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+ If, pursuant to or in connection with a single transaction or
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+you grant is automatically extended to all recipients of the covered
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+
+ A patent license is "discriminatory" if it does not include within
+the scope of its coverage, prohibits the exercise of, or is
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+in the business of distributing software, under which you make payment
+to the third party based on the extent of your activity of conveying
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+contain the covered work, unless you entered into that arrangement,
+or that patent license was granted, prior to 28 March 2007.
+
+ Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.
+
+ 12. No Surrender of Others' Freedom.
+
+ If conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License. If you cannot convey a
+covered work so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you may
+not convey it at all. For example, if you agree to terms that obligate you
+to collect a royalty for further conveying from those to whom you convey
+the Program, the only way you could satisfy both those terms and this
+License would be to refrain entirely from conveying the Program.
+
+ 13. Use with the GNU Affero General Public License.
+
+ Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU Affero General Public License into a single
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+section 13, concerning interaction through a network will apply to the
+combination as such.
+
+ 14. Revised Versions of this License.
+
+ The Free Software Foundation may publish revised and/or new versions of
+the GNU General Public License from time to time. Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+ Each version is given a distinguishing version number. If the
+Program specifies that a certain numbered version of the GNU General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation. If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+ If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+ Later license versions may give you additional or different
+permissions. However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+ 15. Disclaimer of Warranty.
+
+ THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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+IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+ 16. Limitation of Liability.
+
+ IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+ 17. Interpretation of Sections 15 and 16.
+
+ If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+
+ Copyright (C)
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see .
+
+Also add information on how to contact you by electronic and paper mail.
+
+ If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+ Copyright (C)
+ This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+ This is free software, and you are welcome to redistribute it
+ under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License. Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+ You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+.
+
+ The GNU General Public License does not permit incorporating your program
+into proprietary programs. If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library. If this is what you want to do, use the GNU Lesser General
+Public License instead of this License. But first, please read
+.
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..3a6ceab
--- /dev/null
+++ b/README.md
@@ -0,0 +1,48 @@
+## Description
+
+A color constancy filter that applies color correction based on the grayworld assumption.
+
+For more [info](https://www.researchgate.net/publication/275213614_A_New_Color_Correction_Method_for_Underwater_Imaging).
+
+This is [a port of the FFmpeg filter grayworld](https://github.com/FFmpeg/FFmpeg/blob/master/libavfilter/vf_grayworld.c).
+
+### Requirements:
+
+- AviSynth+ 3.6 or later
+
+- Microsoft VisualC++ Redistributable Package 2022 (can be downloaded from [here](https://github.com/abbodi1406/vcredist/releases)) (Windows only)
+
+### Usage:
+
+```
+grayworld (clip input)
+```
+
+### Parameters:
+
+- input\
+ A clip to process.\
+ Must be in RGB(A) 32-bit planar format and in linear light.
+
+### Building:
+
+- Windows\
+ Use solution files.
+
+- Linux
+ ```
+ Requirements:
+ - Git
+ - C++17 compiler
+ - CMake >= 3.16
+ ```
+ ```
+ git clone https://github.com/Asd-g/AviSynthPlus-grayworld && \
+ cd AviSynthPlus-grayworld && \
+ mkdir build && \
+ cd build && \
+
+ cmake ..
+ make -j$(nproc)
+ sudo make install
+ ```
diff --git a/cmake_uninstall.cmake.in b/cmake_uninstall.cmake.in
new file mode 100644
index 0000000..c2d34d4
--- /dev/null
+++ b/cmake_uninstall.cmake.in
@@ -0,0 +1,21 @@
+if(NOT EXISTS "@CMAKE_BINARY_DIR@/install_manifest.txt")
+ message(FATAL_ERROR "Cannot find install manifest: @CMAKE_BINARY_DIR@/install_manifest.txt")
+endif()
+
+file(READ "@CMAKE_BINARY_DIR@/install_manifest.txt" files)
+string(REGEX REPLACE "\n" ";" files "${files}")
+foreach(file ${files})
+ message(STATUS "Uninstalling $ENV{DESTDIR}${file}")
+ if(IS_SYMLINK "$ENV{DESTDIR}${file}" OR EXISTS "$ENV{DESTDIR}${file}")
+ exec_program(
+ "@CMAKE_COMMAND@" ARGS "-E remove \"$ENV{DESTDIR}${file}\""
+ OUTPUT_VARIABLE rm_out
+ RETURN_VALUE rm_retval
+ )
+ if(NOT "${rm_retval}" STREQUAL 0)
+ message(FATAL_ERROR "Problem when removing $ENV{DESTDIR}${file}")
+ endif()
+ else(IS_SYMLINK "$ENV{DESTDIR}${file}" OR EXISTS "$ENV{DESTDIR}${file}")
+ message(STATUS "File $ENV{DESTDIR}${file} does not exist.")
+ endif()
+endforeach()
diff --git a/msvc/grayworld.sln b/msvc/grayworld.sln
new file mode 100644
index 0000000..bdc0911
--- /dev/null
+++ b/msvc/grayworld.sln
@@ -0,0 +1,31 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 16
+VisualStudioVersion = 16.0.32228.343
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "grayworld", "grayworld.vcxproj", "{87B408FB-CE98-40F7-8682-49001A17E14C}"
+EndProject
+Global
+ GlobalSection(SolutionConfigurationPlatforms) = preSolution
+ Debug|x64 = Debug|x64
+ Debug|x86 = Debug|x86
+ Release|x64 = Release|x64
+ Release|x86 = Release|x86
+ EndGlobalSection
+ GlobalSection(ProjectConfigurationPlatforms) = postSolution
+ {87B408FB-CE98-40F7-8682-49001A17E14C}.Debug|x64.ActiveCfg = Debug|x64
+ {87B408FB-CE98-40F7-8682-49001A17E14C}.Debug|x64.Build.0 = Debug|x64
+ {87B408FB-CE98-40F7-8682-49001A17E14C}.Debug|x86.ActiveCfg = Debug|Win32
+ {87B408FB-CE98-40F7-8682-49001A17E14C}.Debug|x86.Build.0 = Debug|Win32
+ {87B408FB-CE98-40F7-8682-49001A17E14C}.Release|x64.ActiveCfg = Release|x64
+ {87B408FB-CE98-40F7-8682-49001A17E14C}.Release|x64.Build.0 = Release|x64
+ {87B408FB-CE98-40F7-8682-49001A17E14C}.Release|x86.ActiveCfg = Release|Win32
+ {87B408FB-CE98-40F7-8682-49001A17E14C}.Release|x86.Build.0 = Release|Win32
+ EndGlobalSection
+ GlobalSection(SolutionProperties) = preSolution
+ HideSolutionNode = FALSE
+ EndGlobalSection
+ GlobalSection(ExtensibilityGlobals) = postSolution
+ SolutionGuid = {FB7A8026-76E8-4DC9-9709-B05301AD40CB}
+ EndGlobalSection
+EndGlobal
diff --git a/msvc/grayworld.vcxproj b/msvc/grayworld.vcxproj
new file mode 100644
index 0000000..d32ba26
--- /dev/null
+++ b/msvc/grayworld.vcxproj
@@ -0,0 +1,148 @@
+
+
+
+
+ Debug
+ Win32
+
+
+ Release
+ Win32
+
+
+ Debug
+ x64
+
+
+ Release
+ x64
+
+
+
+ 16.0
+ {87B408FB-CE98-40F7-8682-49001A17E14C}
+ Win32Proj
+ 10.0
+
+
+
+ Application
+ true
+ v142
+
+
+ DynamicLibrary
+ false
+ Intel C++ Compiler 2022
+
+
+ DynamicLibrary
+ true
+ v142
+
+
+ DynamicLibrary
+ false
+ Intel C++ Compiler 2022
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+ true
+
+
+ false
+ ..\..\AviSynthPlus\avs_core\include;$(IncludePath)
+
+
+ ..\..\AviSynthPlus\avs_core\include;$(IncludePath)
+
+
+ ..\..\AviSynthPlus\avs_core\include;$(IncludePath)
+ false
+
+
+ true
+
+
+
+ WIN32;_DEBUG;_WINDOWS;%(PreprocessorDefinitions)
+ MultiThreadedDebugDLL
+ Level3
+ ProgramDatabase
+ Disabled
+
+
+ MachineX86
+ true
+ Windows
+
+
+
+
+ WIN32;NDEBUG;_WINDOWS;%(PreprocessorDefinitions)
+ MultiThreadedDLL
+ Level3
+ ProgramDatabase
+ AnySuitable
+ true
+ Speed
+ true
+ stdcpp17
+
+
+ MachineX86
+ true
+ Windows
+ true
+
+
+
+
+ stdcpp14
+
+
+
+
+ true
+ AnySuitable
+ true
+ Speed
+ true
+ stdcpp17
+
+
+ true
+
+
+ true
+ libmmds.lib;%(AdditionalDependencies)
+
+
+
+
+
+
+
+
+
+
+
+
+
\ No newline at end of file
diff --git a/msvc/grayworld.vcxproj.filters b/msvc/grayworld.vcxproj.filters
new file mode 100644
index 0000000..5370633
--- /dev/null
+++ b/msvc/grayworld.vcxproj.filters
@@ -0,0 +1,27 @@
+
+
+
+
+ {4FC737F1-C7A5-4376-A066-2A32D752A2FF}
+ cpp;c;cc;cxx;def;odl;idl;hpj;bat;asm;asmx
+
+
+ {93995380-89BD-4b04-88EB-625FBE52EBFB}
+ h;hh;hpp;hxx;hm;inl;inc;xsd
+
+
+ {67DA6AB6-F800-4c08-8B7A-83BB121AAD01}
+ rc;ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe;resx;tiff;tif;png;wav
+
+
+
+
+ Source Files
+
+
+
+
+ Resource Files
+
+
+
\ No newline at end of file
diff --git a/src/grayworld.cpp b/src/grayworld.cpp
new file mode 100644
index 0000000..fa61785
--- /dev/null
+++ b/src/grayworld.cpp
@@ -0,0 +1,220 @@
+#include
+#include
+
+#include "avisynth.h"
+
+void apply_matrix(const float matrix[3][3], const float input[3], float output[3])
+{
+ output[0] = matrix[0][0] * input[0] + matrix[0][1] * input[1] + matrix[0][2] * input[2];
+ output[1] = matrix[1][0] * input[0] + matrix[1][1] * input[1] + matrix[1][2] * input[2];
+ output[2] = matrix[2][0] * input[0] + matrix[2][1] * input[1] + matrix[2][2] * input[2];
+}
+
+static constexpr float lms2lab[3][3]{
+ {0.5774f, 0.5774f, 0.5774f},
+ {0.40825f, 0.40825f, -0.816458f},
+ {0.707f, -0.707f, 0.0f}
+};
+
+static constexpr float lab2lms[3][3]{
+ {0.57735f, 0.40825f, 0.707f},
+ {0.57735f, 0.40825f, -0.707f},
+ {0.57735f, -0.8165f, 0.0f}
+};
+
+static constexpr float rgb2lms[3][3]{
+ {0.3811f, 0.5783f, 0.0402f},
+ {0.1967f, 0.7244f, 0.0782f},
+ {0.0241f, 0.1288f, 0.8444f}
+};
+
+static constexpr float lms2rgb[3][3]{
+ {4.4679f, -3.5873f, 0.1193f},
+ {-1.2186f, 2.3809f, -0.1624f},
+ {0.0497f, -0.2439f, 1.2045f}
+};
+
+void rgb2lab(const float rgb[3], float lab[3])
+{
+ float lms[3];
+
+ apply_matrix(rgb2lms, rgb, lms);
+
+ lms[0] = (lms[0] > 0.0f) ? logf(lms[0]) : -1024.0f;
+ lms[1] = (lms[1] > 0.0f) ? logf(lms[1]) : -1024.0f;
+ lms[2] = (lms[2] > 0.0f) ? logf(lms[2]) : -1024.0f;
+
+ apply_matrix(lms2lab, lms, lab);
+}
+
+void lab2rgb(const float lab[3], float rgb[3])
+{
+ float lms[3];
+
+ apply_matrix(lab2lms, lab, lms);
+
+ lms[0] = expf(lms[0]);
+ lms[1] = expf(lms[1]);
+ lms[2] = expf(lms[2]);
+
+ apply_matrix(lms2rgb, lms, rgb);
+}
+
+void convert_frame(float* tmpplab, PVideoFrame& src, float* line_sum, int* line_count_pels, const int pitch, const int width, const int height)
+{
+ const float* r{ reinterpret_cast(src->GetReadPtr(PLANAR_R)) };
+ const float* g{ reinterpret_cast(src->GetReadPtr(PLANAR_G)) };
+ const float* b{ reinterpret_cast(src->GetReadPtr(PLANAR_B)) };
+
+ float rgb[3];
+ float lab[3];
+
+ for (int y{ 0 }; y < height; ++y)
+ {
+ float* acur{ tmpplab + y * width + width * height };
+ float* bcur{ tmpplab + y * width + 2 * width * height };
+ float* lcur{ tmpplab + y * width };
+
+ line_sum[y] = 0.0f;
+ line_sum[y + height] = 0.0f;
+ line_count_pels[y] = 0;
+
+ for (int x{ 0 }; x < width; ++x)
+ {
+ rgb[0] = r[x];
+ rgb[1] = g[x];
+ rgb[2] = b[x];
+
+ rgb2lab(rgb, lab);
+
+ *(lcur++) = lab[0];
+ *(acur++) = lab[1];
+ *(bcur++) = lab[2];
+
+ line_sum[y] += lab[1];
+ line_sum[y + height] += lab[2];
+ line_count_pels[y]++;
+ }
+
+ r += pitch;
+ g += pitch;
+ b += pitch;
+ }
+}
+
+std::pair compute_correction(float* line_sum, int* line_count_pels, const int height)
+{
+ float asum = 0.0f;
+ float bsum = 0.0f;
+ int pixels = 0;
+
+ for (int y{ 0 }; y < height; ++y)
+ {
+ asum += line_sum[y];
+ bsum += line_sum[y + height];
+ pixels += line_count_pels[y];
+ }
+
+ return std::make_pair(asum / pixels, bsum / pixels);
+}
+
+void correct_frame(PVideoFrame& dst, float* tmpplab, std::pair& avg, const int pitch, const int width, const int height)
+{
+ float* r{ reinterpret_cast(dst->GetWritePtr(PLANAR_R)) };
+ float* g{ reinterpret_cast(dst->GetWritePtr(PLANAR_G)) };
+ float* b{ reinterpret_cast(dst->GetWritePtr(PLANAR_B)) };
+
+ float rgb[3];
+ float lab[3];
+
+ for (int y{ 0 }; y < height; ++y)
+ {
+ float* lcur{ tmpplab + y * width };
+ float* acur{ tmpplab + y * width + width * height };
+ float* bcur{ tmpplab + y * width + 2 * width * height };
+
+ for (int x{ 0 }; x < width; ++x)
+ {
+ lab[0] = *lcur++;
+ lab[1] = *acur++;
+ lab[2] = *bcur++;
+
+ // subtract the average for the color channels
+ lab[1] -= avg.first;
+ lab[2] -= avg.second;
+
+ //convert back to linear rgb
+ lab2rgb(lab, rgb);
+ r[x] = rgb[0];
+ g[x] = rgb[1];
+ b[x] = rgb[2];
+ }
+
+ r += pitch;
+ g += pitch;
+ b += pitch;
+ }
+}
+
+class grayworld : public GenericVideoFilter
+{
+ std::pair avg;
+
+ std::unique_ptrtmpplab;
+ std::unique_ptrline_count_pels;
+ std::unique_ptrline_sum;
+
+public:
+ grayworld(PClip _child, IScriptEnvironment* env)
+ : GenericVideoFilter(_child)
+ {
+ if (!vi.IsRGB() || !vi.IsPlanar() || vi.ComponentSize() != 4)
+ env->ThrowError("grayworld: clip must be in RGB 32-bit planar format.");
+
+ tmpplab = std::make_unique(vi.height * vi.width * 3);
+ line_count_pels = std::make_unique(vi.height);
+ line_sum = std::make_unique(vi.height * 2);
+ }
+
+ PVideoFrame __stdcall GetFrame(int n, IScriptEnvironment* env)
+ {
+ PVideoFrame src{ child->GetFrame(n, env) };
+ PVideoFrame dst{ env->NewVideoFrameP(vi, &src) };
+
+ const int pitch{ src->GetPitch() };
+ const int dst_pitch{ dst->GetPitch() };
+ const int width{ src->GetRowSize() / 4 };
+ const int height{ src->GetHeight() };
+
+ convert_frame(tmpplab.get(), src, line_sum.get(), line_count_pels.get(), pitch / 4, width, height);
+ avg = compute_correction(line_sum.get(), line_count_pels.get(), height);
+ correct_frame(dst, tmpplab.get(), avg, dst_pitch / 4, width, height);
+
+ if (vi.NumComponents() == 4)
+ env->BitBlt(dst->GetWritePtr(PLANAR_A), dst_pitch, src->GetReadPtr(PLANAR_A), pitch, src->GetRowSize(), height);
+
+ return dst;
+ }
+
+ int __stdcall SetCacheHints(int cachehints, int frame_range)
+ {
+ return cachehints == CACHE_GET_MTMODE ? MT_MULTI_INSTANCE : 0;
+ }
+};
+
+AVSValue __cdecl Create_grayworld(AVSValue args, void* user_data, IScriptEnvironment* env)
+{
+ return new grayworld(args[0].AsClip(), env);
+}
+
+const AVS_Linkage* AVS_linkage;
+
+extern "C" __declspec(dllexport)
+const char* __stdcall AvisynthPluginInit3(IScriptEnvironment * env, const AVS_Linkage* const vectors)
+{
+ AVS_linkage = vectors;
+
+ env->AddFunction("grayworld", "c", Create_grayworld, 0);
+
+ return "grayworld";
+}
diff --git a/src/grayworld.rc b/src/grayworld.rc
new file mode 100644
index 0000000..806a9dc
--- /dev/null
+++ b/src/grayworld.rc
@@ -0,0 +1,29 @@
+#include
+
+VS_VERSION_INFO VERSIONINFO
+FILEVERSION 1,0,0,0
+PRODUCTVERSION 1,0,0,0
+FILEFLAGSMASK VS_FFI_FILEFLAGSMASK
+FILEFLAGS 0x0L
+FILEOS VOS__WINDOWS32
+FILETYPE VFT_DLL
+FILESUBTYPE VFT2_UNKNOWN
+BEGIN
+ BLOCK "StringFileInfo"
+ BEGIN
+ BLOCK "040904E4"
+ BEGIN
+ VALUE "Comments", "Adjust white balance using LAB gray world algorithm."
+ VALUE "FileDescription", "grayworld for AviSynth+"
+ VALUE "FileVersion", "1.0.0"
+ VALUE "InternalName", "grayworld"
+ VALUE "OriginalFilename", "grayworld.dll"
+ VALUE "ProductName", "grayworld"
+ VALUE "ProductVersion", "1.0.0"
+ END
+ END
+ BLOCK "VarFileInfo"
+ BEGIN
+ VALUE "Translation", 0x409, 1252
+ END
+END