Rewrite ColorQuantizer based on KGySoft.Drawing code (for saving imag…

…es in GIF format)
zenden2k · Jul 20, 2024 · 1c65cdd · 1c65cdd
1 parent 8eda4c0
commit 1c65cdd
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Showing 10 changed files with 572 additions and 729 deletions.
diff --git a/Source/3rdpart/QColorQuantizer.cpp b/Source/3rdpart/QColorQuantizer.cpp
diff --git a/Source/3rdpart/QColorQuantizer.h b/Source/3rdpart/QColorQuantizer.h
diff --git a/Source/Core/CMakeLists.txt b/Source/Core/CMakeLists.txt
@@ -202,8 +202,9 @@ if(WIN32)
         Images/WebpImageReader.cpp
         Images/HeifImageReader.cpp
         Images/ImageLoader.cpp
-        ../3rdpart/QColorQuantizer.cpp
         Images/GdiPlusImage.cpp
+        Images/ColorQuantizer.cpp
+        Images/OctreeColorQuantizer.cpp
         ../Func/GdiPlusInitializer.cpp
     )
 
@@ -236,7 +237,8 @@ if(WIN32)
         Images/HeifImageReader.h
         Images/AbstractImageReader.h
         Images/ImageLoader.h
-        ../3rdpart/QColorQuantizer.h
+        Images/ColorQuantizer.h
+        Images/OctreeColorQuantizer.h
     )
 else()
     list(APPEND SRC_LIST  

diff --git a/Source/Core/Images/ColorQuantizer.cpp b/Source/Core/Images/ColorQuantizer.cpp
@@ -0,0 +1,91 @@
+#include "ColorQuantizer.h"
+
+#include "OctreeColorQuantizer.h"
+
+using namespace Gdiplus;
+
+std::unique_ptr<Bitmap> ColorQuantizer::getQuantized(Bitmap* sourceBitmap, Gdiplus::Color backgroundColor, UINT nMaxColors /* = 256 */)
+{
+    BYTE alphaThreshold = 0;
+    UINT width = sourceBitmap->GetWidth();
+    UINT height = sourceBitmap->GetHeight();
+    Rect rc(0, 0, width, height);
+    std::unique_ptr<Bitmap> destBitmap;
+    BitmapData dataSource;
+
+    if (sourceBitmap->LockBits(&rc, ImageLockModeRead, PixelFormat32bppARGB, &dataSource) == Ok) {
+        BYTE* pScan0Source = (BYTE*)dataSource.Scan0;
+        UINT strideSource;
+
+        if (dataSource.Stride > 0) {
+            strideSource = dataSource.Stride;
+        } else {
+            pScan0Source += height * dataSource.Stride;
+            strideSource = -dataSource.Stride;
+        }
+
+        BYTE* pRowSource = pScan0Source;
+        OctreeColorQuantizer quantizer(nMaxColors, 8, &dataSource);
+        destBitmap = std::make_unique<Bitmap>(width, height, PixelFormat8bppIndexed);
+
+        for (UINT y = 0; y < height; y++) {
+            BYTE* pPixelSource = pRowSource;
+
+            for (UINT x = 0; x < width; x++) {
+                BYTE b = *pPixelSource++;
+                BYTE g = *pPixelSource++;
+                BYTE r = *pPixelSource++;
+                BYTE a = *pPixelSource++;
+                Gdiplus::Color c(a, r, g, b);
+                if (c.GetA() != 255) {
+                    c = c.GetA() < alphaThreshold ? Color() : BlendWithBackgroundSrgb(c, backgroundColor);
+                }
+
+                quantizer.addColor(c);
+            }
+
+            pRowSource += strideSource;
+        }
+
+        auto pallete = quantizer.generatePalette();
+        MyPalette mypal(pallete.get(), backgroundColor, alphaThreshold);
+
+        BitmapData dataDest;
+        destBitmap->SetPalette(pallete.get());
+        if (destBitmap->LockBits(&rc, ImageLockModeWrite, PixelFormat8bppIndexed, &dataDest) == Ok) {
+            BYTE* pRowSource = pScan0Source;
+
+            BYTE* pRowDest = (BYTE*)dataDest.Scan0;
+            UINT strideDest;
+
+            if (dataDest.Stride > 0) {
+                strideDest = dataDest.Stride;
+            } else {
+                pRowDest += height * dataDest.Stride;
+                strideDest = -dataDest.Stride;
+            }
+
+            for (UINT y = 0; y < height; y++) {
+                BYTE* pPixelSource = pRowSource;
+                BYTE* pPixelDest = pRowDest;
+
+                for (UINT x = 0; x < width; x++) {
+                    BYTE b = *pPixelSource++;
+                    BYTE g = *pPixelSource++;
+                    BYTE r = *pPixelSource++;
+                    BYTE a = *pPixelSource++;
+
+                    BYTE index = (BYTE)mypal.getNearestColorIndex(Gdiplus::Color(a, r, g, b));
+
+                    *pPixelDest++ = index;
+                }
+
+                pRowSource += strideSource;
+                pRowDest += strideDest;
+            }
+            destBitmap->UnlockBits(&dataDest);
+        }
+        sourceBitmap->UnlockBits(&dataSource);
+    }
+    return destBitmap;
+}
diff --git a/Source/Core/Images/ColorQuantizer.h b/Source/Core/Images/ColorQuantizer.h
@@ -0,0 +1,11 @@
+
+#pragma once
+#include <memory>
+
+#include <windows.h>
+#include "3rdpart/GdiplusH.h"
+
+class ColorQuantizer {
+public:
+    std::unique_ptr<Gdiplus::Bitmap> getQuantized(Gdiplus::Bitmap* pSource, Gdiplus::Color backgroundColor, UINT nMaxColors = 256);
+};