move swffilter use of BitmapEx::GetAlpha inside vcl

Change-Id: I22f489a26b8566ddc00c0c77f95127adb8eb2489
Reviewed-on: https://gerrit.libreoffice.org/51324
Reviewed-by: Michael Meeks <michael.meeks@collabora.com>
Tested-by: Jenkins <ci@libreoffice.org>

3 files changed, 80 insertions, 75 deletions

diff --git a/filter/source/flash/swfwriter1.cxx b/filter/source/flash/swfwriter1.cxx
index 09ed4f647efc..57923f8dbd13 100644
--- a/filter/source/flash/swfwriter1.cxx
+++ b/filter/source/flash/swfwriter1.cxx
@@ -694,71 +694,6 @@ void Writer::Impl_writeText( const Point& rPos, const OUString& rText, const lon
     }
 }
 
-// AS: Because JPEGs require the alpha channel provided separately (JPEG does not
-//  natively support alpha channel, but SWF lets you provide it separately), we
-//  extract the alpha channel into a separate array here.
-void getBitmapData( const BitmapEx& aBmpEx, sal_uInt8*& tgadata, sal_uInt8*& tgaAlphadata, sal_uInt32& nWidth, sal_uInt32& nHeight )
-{
-    if( !aBmpEx.IsEmpty() )
-    {
-        Bitmap aBmp( aBmpEx.GetBitmap() );
-        Bitmap::ScopedReadAccess pRAcc(aBmp);
-
-        if( pRAcc )
-        {
-            AlphaMask   aAlpha;
-            nWidth = pRAcc->Width();
-            nHeight = pRAcc->Height();
-            tgadata = new sal_uInt8[nWidth*nHeight*4];
-            tgaAlphadata = new sal_uInt8[nWidth*nHeight];
-            sal_uInt8* p = tgadata, *pAlpha = tgaAlphadata;
-
-
-            if( aBmpEx.IsAlpha() )
-                aAlpha = aBmpEx.GetAlpha();
-            else if( aBmpEx.IsTransparent() )
-                aAlpha = aBmpEx.GetMask();
-            else
-            {
-                sal_uInt8 cAlphaVal = 0;
-                aAlpha = AlphaMask( aBmp.GetSizePixel(), &cAlphaVal );
-            }
-
-            AlphaMask::ScopedReadAccess pAAcc(aAlpha);
-
-            if( pAAcc )
-            {
-                for( sal_uInt32 nY = 0; nY < nHeight; nY++ )
-                {
-                    Scanline pScanlineAA = pAAcc->GetScanline( nY );
-                    for( sal_uInt32 nX = 0; nX < nWidth; nX++ )
-                    {
-                        const sal_uInt8     nAlpha = pAAcc->GetIndexFromData( pScanlineAA, nX );
-                        const BitmapColor   aPixelColor( pRAcc->GetColor( nY, nX ) );
-
-                        if( nAlpha == 0xff )
-                        {
-                            *p++ = 0;
-                            *p++ = 0;
-                            *p++ = 0;
-                            *p++ = 0;
-                        }
-                        else
-                        {
-                            *p++ = 0xff-nAlpha;
-                            *p++ = aPixelColor.GetRed();
-                            *p++ = aPixelColor.GetGreen();
-                            *p++ = aPixelColor.GetBlue();
-                        }
-                        *pAlpha++ = 0xff - nAlpha;
-                    }
-                }
-            }
-        }
-    }
-}
-
-
 sal_uInt16 Writer::defineBitmap( const BitmapEx &bmpSource, sal_Int32 nJPEGQualityLevel )
 {
     BitmapChecksum bmpChecksum = bmpSource.GetChecksum();
@@ -776,21 +711,22 @@ sal_uInt16 Writer::defineBitmap( const BitmapEx &bmpSource, sal_Int32 nJPEGQuali
     //  or Lossless compress it.
 
     // Figure out lossless size
-    sal_uInt8 *pImageData, *pAlphaData;
-    sal_uInt32 width(0), height(0);
+    std::vector<sal_uInt8> aImageData, aAlphaData;
 
-    getBitmapData( bmpSource, pImageData, pAlphaData, width, height );
+    sal_uInt32 width = bmpSource.GetPrefSize().Width();
+    sal_uInt32 height = bmpSource.GetPrefSize().Height();
+    bmpSource.GetSplitData(aImageData, aAlphaData );
     sal_uInt32 raw_size = width * height * 4;
     uLongf compressed_size = raw_size + static_cast<sal_uInt32>(raw_size/100) + 12;
     std::unique_ptr<sal_uInt8[]> pCompressed(new sal_uInt8[ compressed_size ]);
 
 #ifdef DBG_UTIL
-    if(compress2(pCompressed.get(), &compressed_size, pImageData, raw_size, Z_BEST_COMPRESSION) != Z_OK)
+    if(compress2(pCompressed.get(), &compressed_size, aImageData.data(), raw_size, Z_BEST_COMPRESSION) != Z_OK)
     {
         SAL_WARN( "filter.flash", "compress2 failed!" ); ((void)0);
     }
 #else
-    compress2(pCompressed.get(), &compressed_size, pImageData, raw_size, Z_BEST_COMPRESSION);
+    compress2(pCompressed.get(), &compressed_size, aImageData.data(), raw_size, Z_BEST_COMPRESSION);
 #endif
 
     // AS: SWF files let you provide an Alpha mask for JPEG images, but we have
@@ -803,15 +739,19 @@ sal_uInt16 Writer::defineBitmap( const BitmapEx &bmpSource, sal_Int32 nJPEGQuali
         pAlphaCompressed.reset(new sal_uInt8[ compressed_size ]);
 
 #ifdef DBG_UTIL
-        if(compress2(pAlphaCompressed.get(), &alpha_compressed_size, pAlphaData, width * height, Z_BEST_COMPRESSION) != Z_OK)
+        if(compress2(pAlphaCompressed.get(), &alpha_compressed_size, aAlphaData.data(), width * height, Z_BEST_COMPRESSION) != Z_OK)
         {
             SAL_WARN( "filter.flash", "compress2 failed!" ); ((void)0);
         }
 #else
-        compress2(pAlphaCompressed.get(), &alpha_compressed_size, pAlphaData, width * height, Z_BEST_COMPRESSION);
+        compress2(pAlphaCompressed.get(), &alpha_compressed_size, aAlphaData.data(), width * height, Z_BEST_COMPRESSION);
 #endif
     }
 
+    // clear these early for less peak memory usage
+    aImageData.resize(0);
+    aAlphaData.resize(0);
+
     // Figure out JPEG size
     const sal_uInt8* pJpgData = nullptr;
     sal_uInt32 nJpgDataLength = 0xffffffff;
@@ -843,9 +783,6 @@ sal_uInt16 Writer::defineBitmap( const BitmapEx &bmpSource, sal_Int32 nJPEGQuali
     else
         Impl_writeBmp( nBitmapId, width, height, pCompressed.get(), compressed_size );
 
-    delete[] pImageData;
-    delete[] pAlphaData;
-
     return nBitmapId;
 }
 
diff --git a/include/vcl/bitmapex.hxx b/include/vcl/bitmapex.hxx
index 9ab88686df36..4876180e10c4 100644
--- a/include/vcl/bitmapex.hxx
+++ b/include/vcl/bitmapex.hxx
@@ -95,6 +95,11 @@ public:
 
 public:
 
+    /**
+     * @brief extract the bitmap and alpha data separately. Used by the SWF filter.
+     */
+    void GetSplitData( std::vector<sal_uInt8>& rvColorData, std::vector<sal_uInt8>& rvAlphaData ) const;
+
     /** Convert bitmap format
 
         @param eConversion
diff --git a/vcl/source/gdi/bitmapex.cxx b/vcl/source/gdi/bitmapex.cxx
index 07d5d19e7869..1dcc72befeaf 100644
--- a/vcl/source/gdi/bitmapex.cxx
+++ b/vcl/source/gdi/bitmapex.cxx
@@ -1378,4 +1378,67 @@ void BitmapEx::AdjustTransparency(sal_uInt8 cTrans)
     }
     *this = BitmapEx( GetBitmap(), aAlpha );
 }
+
+// AS: Because JPEGs require the alpha channel provided separately (JPEG does not
+//  natively support alpha channel, but SWF lets you provide it separately), we
+//  extract the alpha channel into a separate array here.
+void BitmapEx::GetSplitData( std::vector<sal_uInt8>& rvColorData, std::vector<sal_uInt8>& rvAlphaData ) const
+{
+    if( IsEmpty() )
+        return;
+
+    Bitmap aBmp( GetBitmap() );
+    Bitmap::ScopedReadAccess pRAcc(aBmp);
+
+    assert( pRAcc );
+
+    AlphaMask   aAlpha;
+    sal_uInt32 nWidth = pRAcc->Width();
+    sal_uInt32 nHeight = pRAcc->Height();
+    rvColorData.resize(nWidth*nHeight*4);
+    rvAlphaData.resize(nWidth*nHeight);
+    sal_uInt8* p = rvColorData.data(), *pAlpha = rvAlphaData.data();
+
+
+    if( IsAlpha() )
+        aAlpha = GetAlpha();
+    else if( IsTransparent() )
+        aAlpha = GetMask();
+    else
+    {
+        sal_uInt8 cAlphaVal = 0;
+        aAlpha = AlphaMask( aBmp.GetSizePixel(), &cAlphaVal );
+    }
+
+    AlphaMask::ScopedReadAccess pAAcc(aAlpha);
+
+    assert( pAAcc );
+
+    for( sal_uInt32 nY = 0; nY < nHeight; nY++ )
+    {
+        Scanline pScanlineAA = pAAcc->GetScanline( nY );
+        for( sal_uInt32 nX = 0; nX < nWidth; nX++ )
+        {
+            const sal_uInt8     nAlpha = pAAcc->GetIndexFromData( pScanlineAA, nX );
+            const BitmapColor   aPixelColor( pRAcc->GetColor( nY, nX ) );
+
+            if( nAlpha == 0xff )
+            {
+                *p++ = 0;
+                *p++ = 0;
+                *p++ = 0;
+                *p++ = 0;
+            }
+            else
+            {
+                *p++ = 0xff-nAlpha;
+                *p++ = aPixelColor.GetRed();
+                *p++ = aPixelColor.GetGreen();
+                *p++ = aPixelColor.GetBlue();
+            }
+            *pAlpha++ = 0xff - nAlpha;
+        }
+    }
+}
+
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */