1 files changed, 99 insertions, 0 deletions
diff --git a/vcl/source/bitmap/BitmapPopArtFilter.cxx b/vcl/source/bitmap/BitmapPopArtFilter.cxx
new file mode 100644
index 000000000..ce37c91fd
--- /dev/null
+++ b/vcl/source/bitmap/BitmapPopArtFilter.cxx
@@ -0,0 +1,99 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ */
+
+#include <tools/solar.h>
+#include <vcl/bitmap.hxx>
+#include <vcl/bitmapex.hxx>
+#include <vcl/BitmapPopArtFilter.hxx>
+
+#include <bitmap/BitmapWriteAccess.hxx>
+
+BitmapEx BitmapPopArtFilter::execute(BitmapEx const& rBitmapEx) const
+{
+    Bitmap aBitmap(rBitmapEx.GetBitmap());
+
+    bool bRet = isPalettePixelFormat(aBitmap.getPixelFormat())
+                || aBitmap.Convert(BmpConversion::N8BitColors);
+
+    if (bRet)
+    {
+        bRet = false;
+
+        BitmapScopedWriteAccess pWriteAcc(aBitmap);
+
+        if (pWriteAcc)
+        {
+            const sal_Int32 nWidth = pWriteAcc->Width();
+            const sal_Int32 nHeight = pWriteAcc->Height();
+            const int nEntryCount = 1 << pWriteAcc->GetBitCount();
+            int n = 0;
+            std::vector<PopArtEntry> aPopArtTable(nEntryCount);
+
+            for (n = 0; n < nEntryCount; n++)
+            {
+                PopArtEntry& rEntry = aPopArtTable[n];
+                rEntry.mnIndex = static_cast<sal_uInt16>(n);
+                rEntry.mnCount = 0;
+            }
+
+            // get pixel count for each palette entry
+            for (sal_Int32 nY = 0; nY < nHeight; nY++)
+            {
+                Scanline pScanline = pWriteAcc->GetScanline(nY);
+                for (sal_Int32 nX = 0; nX < nWidth; nX++)
+                {
+                    aPopArtTable[pWriteAcc->GetIndexFromData(pScanline, nX)].mnCount++;
+                }
+            }
+
+            // sort table
+            std::sort(aPopArtTable.begin(), aPopArtTable.end(),
+                      [](const PopArtEntry& lhs, const PopArtEntry& rhs) {
+                          return lhs.mnCount > rhs.mnCount;
+                      });
+
+            // get last used entry
+            sal_uLong nFirstEntry;
+            sal_uLong nLastEntry = 0;
+
+            for (n = 0; n < nEntryCount; n++)
+            {
+                if (aPopArtTable[n].mnCount)
+                    nLastEntry = n;
+            }
+
+            // rotate palette (one entry)
+            const BitmapColor aFirstCol(pWriteAcc->GetPaletteColor(
+                sal::static_int_cast<sal_uInt16>(aPopArtTable[0].mnIndex)));
+
+            for (nFirstEntry = 0; nFirstEntry < nLastEntry; nFirstEntry++)
+            {
+                pWriteAcc->SetPaletteColor(
+                    sal::static_int_cast<sal_uInt16>(aPopArtTable[nFirstEntry].mnIndex),
+                    pWriteAcc->GetPaletteColor(
+                        sal::static_int_cast<sal_uInt16>(aPopArtTable[nFirstEntry + 1].mnIndex)));
+            }
+
+            pWriteAcc->SetPaletteColor(
+                sal::static_int_cast<sal_uInt16>(aPopArtTable[nLastEntry].mnIndex), aFirstCol);
+
+            // cleanup
+            pWriteAcc.reset();
+            bRet = true;
+        }
+    }
+
+    if (bRet)
+        return BitmapEx(aBitmap);
+
+    return BitmapEx();
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */