diff --git a/python/core/raster/qgsrasterdataprovider.sip b/python/core/raster/qgsrasterdataprovider.sip
index 67208258091..f4da2bd2d52 100644
--- a/python/core/raster/qgsrasterdataprovider.sip
+++ b/python/core/raster/qgsrasterdataprovider.sip
@@ -135,12 +135,12 @@ class QgsRasterDataProvider : QgsDataProvider, QgsRasterInterface
     // TODO: Get the file masks supported by this provider, suitable for feeding into the file open dialog box
 
     /** Returns data type for the band specified by number */
-    virtual QgsRasterBlock::DataType dataType( int bandNo ) const;
+    virtual QgsRasterBlock::DataType dataType( int bandNo ) const = 0;
 
     /** Returns source data type for the band specified by number,
      *  source data type may be shorter than dataType
      */
-    virtual QgsRasterBlock::DataType srcDataType( int bandNo ) const;
+    virtual QgsRasterBlock::DataType srcDataType( int bandNo ) const = 0;
 
     /** Returns data type for the band specified by number */
     virtual int colorInterpretation( int theBandNo ) const;
@@ -388,9 +388,6 @@ class QgsRasterDataProvider : QgsDataProvider, QgsRasterInterface
     static QString makeTableCell( const QString & value );
     static QString makeTableCells( const QStringList & values );
 
-    /** \brief Set null value in char */
-    QByteArray noValueBytes( int theBandNo );
-
     /** Time stamp of data source in the moment when data/metadata were loaded by provider */
     virtual QDateTime timestamp() const;
 
diff --git a/python/gui/raster/qgsmultibandcolorrendererwidget.sip b/python/gui/raster/qgsmultibandcolorrendererwidget.sip
index 1237f5e99be..13cb3e9a0ae 100644
--- a/python/gui/raster/qgsmultibandcolorrendererwidget.sip
+++ b/python/gui/raster/qgsmultibandcolorrendererwidget.sip
@@ -20,5 +20,5 @@ class QgsMultiBandColorRendererWidget: QgsRasterRendererWidget
     int selectedBand( int index = 0 );
 
   public slots:
-    void loadMinMax( int theBandNo, double theMin, double theMax );
+    void loadMinMax( int theBandNo, double theMin, double theMax, int theOrigin );
 };
diff --git a/src/core/raster/qgsrasterblock.cpp b/src/core/raster/qgsrasterblock.cpp
index c2cd0f9db90..205138a891d 100644
--- a/src/core/raster/qgsrasterblock.cpp
+++ b/src/core/raster/qgsrasterblock.cpp
@@ -75,7 +75,8 @@ bool QgsRasterBlock::reset( DataType theDataType, int theWidth, int theHeight, d
   if ( typeIsNumeric( theDataType ) )
   {
     QgsDebugMsg( "Numeric type" );
-    int tSize = typeSize( theDataType ) / 8;
+    size_t tSize = typeSize( theDataType );
+    QgsDebugMsg( QString( "allocate %1 bytes" ).arg( tSize * theWidth * theHeight ) );
     mData = QgsMalloc( tSize * theWidth * theHeight );
     if ( mData == 0 )
     {
@@ -341,6 +342,36 @@ bool QgsRasterBlock::setColor( size_t index, QRgb color )
   return true;
 }
 
+bool QgsRasterBlock::setIsNoData( int row, int column )
+{
+  return setIsNoData(( size_t )row*column );
+}
+
+bool QgsRasterBlock::setIsNoData( size_t index )
+{
+  return setValue( index, mNoDataValue );
+}
+
+bool QgsRasterBlock::setIsNoData()
+{
+  if ( !mData )
+  {
+    QgsDebugMsg( "Data block not allocated" );
+    return false;
+  }
+
+  int dataTypeSize = typeSize( mDataType );
+  QByteArray noDataByteArray = valueBytes( mDataType, mNoDataValue );
+
+  char *nodata = noDataByteArray.data();
+  for ( size_t i = 0; i < ( size_t )mWidth*mHeight; i++ )
+  {
+    memcpy(( char* )mData + i*dataTypeSize, nodata, dataTypeSize );
+  }
+
+  return true;
+}
+
 char * QgsRasterBlock::bits( size_t index )
 {
   // Not testing type to avoid too much overhead because this method is called per pixel
@@ -481,7 +512,7 @@ QString QgsRasterBlock::printValue( double value )
 
 void * QgsRasterBlock::convert( void *srcData, QgsRasterBlock::DataType srcDataType, QgsRasterBlock::DataType destDataType, size_t size )
 {
-  int destDataTypeSize = typeSize( destDataType ) / 8;
+  int destDataTypeSize = typeSize( destDataType );
   void *destData = QgsMalloc( destDataTypeSize * size );
   for ( size_t i = 0; i < size; i++ )
   {
@@ -492,3 +523,53 @@ void * QgsRasterBlock::convert( void *srcData, QgsRasterBlock::DataType srcDataT
   }
   return destData;
 }
+
+QByteArray QgsRasterBlock::valueBytes( DataType theDataType, double theValue )
+{
+  size_t size = QgsRasterBlock::typeSize( theDataType );
+  QByteArray ba;
+  ba.resize(( int )size );
+  char * data = ba.data();
+  unsigned char uc;
+  unsigned short us;
+  short s;
+  unsigned int ui;
+  int i;
+  float f;
+  double d;
+  // TODO: define correct data types (typedef) like in GDAL
+  switch ( theDataType )
+  {
+    case QgsRasterBlock::Byte:
+      uc = ( unsigned char )theValue;
+      memcpy( data, &uc, size );
+      break;
+    case QgsRasterBlock::UInt16:
+      us = ( unsigned short )theValue;
+      memcpy( data, &us, size );
+      break;
+    case QgsRasterBlock::Int16:
+      s = ( short )theValue;
+      memcpy( data, &s, size );
+      break;
+    case QgsRasterBlock::UInt32:
+      ui = ( unsigned int )theValue;
+      memcpy( data, &ui, size );
+      break;
+    case QgsRasterBlock::Int32:
+      i = ( int )theValue;
+      memcpy( data, &i, size );
+      break;
+    case QgsRasterBlock::Float32:
+      f = ( float )theValue;
+      memcpy( data, &f, size );
+      break;
+    case QgsRasterBlock::Float64:
+      d = ( double )theValue;
+      memcpy( data, &d, size );
+      break;
+    default:
+      QgsDebugMsg( "Data type is not supported" );
+  }
+  return ba;
+}
diff --git a/src/core/raster/qgsrasterblock.h b/src/core/raster/qgsrasterblock.h
index 025dc568696..2afd703a1a8 100644
--- a/src/core/raster/qgsrasterblock.h
+++ b/src/core/raster/qgsrasterblock.h
@@ -92,41 +92,43 @@ class CORE_EXPORT QgsRasterBlock
     //bool isValid() const { return mValid; }
     bool isEmpty() const;
 
+    // Return data type size in bytes
     static int typeSize( int dataType )
     {
       // Modified and extended copy from GDAL
       switch ( dataType )
       {
         case Byte:
-          return 8;
+          return 1;
 
         case UInt16:
         case Int16:
-          return 16;
+          return 2;
 
         case UInt32:
         case Int32:
         case Float32:
         case CInt16:
-          return 32;
+          return 4;
 
         case Float64:
         case CInt32:
         case CFloat32:
-          return 64;
+          return 8;
 
         case CFloat64:
-          return 128;
+          return 16;
 
         case ARGB32:
         case ARGB32_Premultiplied:
-          return 32;
+          return 4;
 
         default:
           return 0;
       }
     }
 
+    // Data type in bytes
     int dataTypeSize( int bandNo ) const
     {
       Q_UNUSED( bandNo );
@@ -165,6 +167,9 @@ class CORE_EXPORT QgsRasterBlock
      * @return true if value is nodata */
     bool isNoDataValue( double value ) const;
 
+    // get byte array representing no data value
+    static QByteArray valueBytes( DataType theDataType, double theValue );
+
     /** \brief Read a single value
      *  @param row row index
      *  @param column column index
@@ -218,6 +223,21 @@ class CORE_EXPORT QgsRasterBlock
      *  @return true on success */
     bool setColor( int row, int column, QRgb color );
 
+    /** \brief Set no data on pixel
+     *  @param row row index
+     *  @param column column index
+     *  @return true on success */
+    bool setIsNoData( int row, int column );
+
+    /** \brief Set no data on pixel
+     *  @param index data matrix index
+     *  @return true on success */
+    bool setIsNoData( size_t index );
+
+    /** \brief Set the whole block to no data
+     *  @return true on success */
+    bool setIsNoData( );
+
     /** \brief Set color on index (indexed line by line)
      *  @param index data matrix index
      *  @param color the color to be set, QRgb value
@@ -289,7 +309,6 @@ class CORE_EXPORT QgsRasterBlock
     static QImage::Format imageFormat( QgsRasterBlock::DataType theDataType );
     static DataType dataType( QImage::Format theFormat );
 
-
     // Valid
     //bool isValid;
 
diff --git a/src/core/raster/qgsrasterdataprovider.cpp b/src/core/raster/qgsrasterdataprovider.cpp
index c4ec50e9803..d282e89028c 100644
--- a/src/core/raster/qgsrasterdataprovider.cpp
+++ b/src/core/raster/qgsrasterdataprovider.cpp
@@ -46,86 +46,12 @@ double QgsRasterDataProvider::noDataValue( int bandNo ) const
   return mInternalNoDataValue.value( bandNo -1 );
 }
 
-#if 0
-void QgsRasterDataProvider::readBlock( int bandNo, QgsRectangle
-                                       const & viewExtent, int width,
-                                       int height,
-                                       QgsCoordinateReferenceSystem theSrcCRS,
-                                       QgsCoordinateReferenceSystem theDestCRS,
-                                       void *data )
+QgsRasterBlock * QgsRasterDataProvider::block( int theBandNo, QgsRectangle  const & theExtent, int theWidth, int theHeight )
 {
-  QgsDebugMsg( "Entered" );
-  QgsDebugMsg( "viewExtent = " + viewExtent.toString() );
+  QgsDebugMsg( QString( "theBandNo = %1 theWidth = %2 theHeight = %3" ).arg( theBandNo ).arg( theWidth ).arg( theHeight ) );
+  QgsDebugMsg( QString( "theExtent = %1" ).arg( theExtent.toString() ) );
 
-  if ( ! theSrcCRS.isValid() || ! theDestCRS.isValid() || theSrcCRS == theDestCRS )
-  {
-    readBlock( bandNo, viewExtent, width, height, data );
-    return;
-  }
-
-  QTime time;
-  time.start();
-
-  double mMaxSrcXRes = 0;
-  double mMaxSrcYRes = 0;
-
-  if ( capabilities() & QgsRasterDataProvider::ExactResolution )
-  {
-    mMaxSrcXRes = extent().width() / xSize();
-    mMaxSrcYRes = extent().height() / ySize();
-  }
-
-  QgsRasterProjector myProjector( theSrcCRS, theDestCRS, viewExtent, height, width, mMaxSrcXRes, mMaxSrcYRes, extent() );
-
-  QgsDebugMsg( QString( "create projector time  (ms): %1" ).arg( time.elapsed() ) );
-
-  // TODO: init data by nulls
-
-  // If we zoom out too much, projector srcRows / srcCols maybe 0, which can cause problems in providers
-  if ( myProjector.srcRows() <= 0 || myProjector.srcCols() <= 0 )
-    return;
-
-  // Allocate memory for not projected source data
-  size_t mySize = dataTypeSize( bandNo ) / 8;
-  void *mySrcData = malloc( mySize * myProjector.srcRows() * myProjector.srcCols() );
-
-  time.restart();
-
-  readBlock( bandNo, myProjector.srcExtent(), myProjector.srcCols(), myProjector.srcRows(), mySrcData );
-
-  QgsDebugMsg( QString( "read not projected block time  (ms): %1" ).arg( time.elapsed() ) );
-  time.restart();
-
-  // Project data from source
-  int mySrcRow;
-  int mySrcCol;
-  int mySrcOffset;
-  int myDestOffset;
-  for ( int r = 0; r < height; r++ )
-  {
-    for ( int c = 0; c < width; c++ )
-    {
-      myProjector.srcRowCol( r, c, &mySrcRow, &mySrcCol );
-      mySrcOffset = mySize * ( mySrcRow * myProjector.srcCols() + mySrcCol );
-      myDestOffset = mySize * ( r * width + c );
-      // retype to char is just to avoid g++ warning
-      memcpy(( char* ) data + myDestOffset, ( char* )mySrcData + mySrcOffset, mySize );
-    }
-  }
-  QgsDebugMsg( QString( "reproject block time  (ms): %1" ).arg( time.elapsed() ) );
-
-  free( mySrcData );
-}
-#endif
-
-//void * QgsRasterDataProvider::readBlock( int bandNo, QgsRectangle  const & extent, int width, int height )
-QgsRasterBlock * QgsRasterDataProvider::block( int bandNo, QgsRectangle  const & extent, int width, int height )
-{
-  QgsDebugMsg( QString( "bandNo = %1 width = %2 height = %3" ).arg( bandNo ).arg( width ).arg( height ) );
-
-  //void * data = QgsMalloc( dataTypeSize( bandNo ) * width * height );
-
-  QgsRasterBlock *block = new QgsRasterBlock( dataType( bandNo ), width, height, noDataValue( bandNo ) );
+  QgsRasterBlock *block = new QgsRasterBlock( dataType( theBandNo ), theWidth, theHeight, noDataValue( theBandNo ) );
 
   if ( block->isEmpty() )
   {
@@ -133,16 +59,145 @@ QgsRasterBlock * QgsRasterDataProvider::block( int bandNo, QgsRectangle  const &
     return block;
   }
 
-  readBlock( bandNo, extent, width, height, block->data() );
+  // Read necessary extent only
+  QgsRectangle tmpExtent = extent().intersect( &theExtent );
+
+  if ( tmpExtent.isEmpty() )
+  {
+    QgsDebugMsg( "Extent outside provider extent" );
+    block->setIsNoData();
+    return block;
+  }
+
+  double xRes = theExtent.width() / theWidth;
+  double yRes = theExtent.height() / theHeight;
+  double tmpXRes, tmpYRes;
+  double providerXRes = 0;
+  double providerYRes = 0;
+  if ( capabilities() & ExactResolution )
+  {
+    providerXRes = extent().width() / xSize();
+    providerYRes = extent().height() / ySize();
+    tmpXRes = qMax( providerXRes, xRes );
+    tmpYRes = qMax( providerYRes, yRes );
+    if ( doubleNear( tmpXRes, xRes ) ) tmpXRes = xRes;
+    if ( doubleNear( tmpYRes, yRes ) ) tmpYRes = yRes;
+  }
+  else
+  {
+    tmpXRes = xRes;
+    tmpYRes = yRes;
+  }
+
+  if ( tmpExtent != theExtent ||
+       tmpXRes > xRes || tmpYRes > yRes )
+  {
+    // Read smaller extent or lower resolution
+
+    // Calculate row/col limits (before tmpExtent is aligned)
+    int fromRow = qRound(( theExtent.yMaximum() - tmpExtent.yMaximum() ) / yRes );
+    int toRow = qRound(( theExtent.yMaximum() - tmpExtent.yMinimum() ) / yRes ) - 1;
+    int fromCol = qRound(( tmpExtent.xMinimum() - theExtent.xMinimum() ) / xRes ) ;
+    int toCol = qRound(( tmpExtent.xMaximum() - theExtent.xMinimum() ) / xRes ) - 1;
+
+    QgsDebugMsg( QString( "fromRow = %1 toRow = %2 fromCol = %3 toCol = %4" ).arg( fromRow ).arg( toRow ).arg( fromCol ).arg( toCol ) );
+
+    if ( fromRow < 0 || fromRow >= theHeight || toRow < 0 || toRow >= theHeight ||
+         fromCol < 0 || fromCol >= theWidth || toCol < 0 || toCol >= theWidth )
+    {
+      // Should not happen
+      QgsDebugMsg( "Row or column limits out of range" );
+      return block;
+    }
+
+    // If lower source resolution is used, the extent must beS aligned to original
+    // resolution to avoid possible shift due to resampling
+    if ( tmpXRes > xRes )
+    {
+      int col = floor(( tmpExtent.xMinimum() - extent().xMinimum() ) / providerXRes );
+      tmpExtent.setXMinimum( extent().xMinimum() + col * providerXRes );
+      col = ceil(( tmpExtent.xMaximum() - extent().xMinimum() ) / providerXRes );
+      tmpExtent.setXMaximum( extent().xMinimum() + col * providerXRes );
+    }
+    if ( tmpYRes > yRes )
+    {
+      int row = floor(( extent().yMaximum() - tmpExtent.yMaximum() ) / providerYRes );
+      tmpExtent.setYMaximum( extent().yMaximum() - row * providerYRes );
+      row = ceil(( extent().yMaximum() - tmpExtent.yMinimum() ) / providerYRes );
+      tmpExtent.setYMinimum( extent().yMaximum() - row * providerYRes );
+    }
+    int tmpWidth = qRound( tmpExtent.width() / tmpXRes );
+    int tmpHeight = qRound( tmpExtent.height() / tmpYRes );
+    tmpXRes = tmpExtent.width() / tmpWidth;
+    tmpYRes = tmpExtent.height() / tmpHeight;
+
+    QgsDebugMsg( QString( "Reading smaller block tmpWidth = %1 theHeight = %2" ).arg( tmpWidth ).arg( tmpHeight ) );
+    QgsDebugMsg( QString( "tmpExtent = %1" ).arg( tmpExtent.toString() ) );
+
+    block->setIsNoData();
+
+    QgsRasterBlock *tmpBlock = new QgsRasterBlock( dataType( theBandNo ), tmpWidth, tmpHeight, noDataValue( theBandNo ) );
+
+    readBlock( theBandNo, tmpExtent, tmpWidth, tmpHeight, tmpBlock->data() );
+
+    int pixelSize = dataTypeSize( theBandNo );
+
+    double xMin = theExtent.xMinimum();
+    double yMax = theExtent.yMaximum();
+    double tmpXMin = tmpExtent.xMinimum();
+    double tmpYMax = tmpExtent.yMaximum();
+
+    for ( int row = fromRow; row <= toRow; row++ )
+    {
+      double y = yMax - ( row + 0.5 ) * yRes;
+      int tmpRow = floor(( tmpYMax - y ) / tmpYRes );
+
+      for ( int col = fromCol; col <= toCol; col++ )
+      {
+        double x = xMin + ( col + 0.5 ) * xRes;
+        int tmpCol = floor(( x - tmpXMin ) / tmpXRes );
+
+        if ( tmpRow < 0 || tmpRow >= tmpHeight || tmpCol < 0 || tmpCol >= tmpWidth )
+        {
+          QgsDebugMsg( "Source row or column limits out of range" );
+          block->setIsNoData(); // so that the problem becomes obvious and fixed
+          delete tmpBlock;
+          return block;
+        }
+
+        size_t tmpIndex = tmpRow * tmpWidth + tmpCol;
+        size_t index = row * theWidth + col;
+
+        char *tmpBits = tmpBlock->bits( tmpIndex );
+        char *bits = block->bits( index );
+        if ( !tmpBits )
+        {
+          QgsDebugMsg( QString( "Cannot get input block data tmpRow = %1 tmpCol = %2 tmpIndex = %3." ).arg( tmpRow ).arg( tmpCol ).arg( tmpIndex ) );
+          continue;
+        }
+        if ( !bits )
+        {
+          QgsDebugMsg( "Cannot set output block data." );
+          continue;
+        }
+        memcpy( bits, tmpBits, pixelSize );
+      }
+    }
+
+    delete tmpBlock;
+  }
+  else
+  {
+    readBlock( theBandNo, theExtent, theWidth, theHeight, block->data() );
+  }
 
   // apply user no data values
   // TODO: there are other readBlock methods where no data are not applied
-  QList<QgsRasterBlock::Range> myNoDataRangeList = userNoDataValue( bandNo );
+  QList<QgsRasterBlock::Range> myNoDataRangeList = userNoDataValue( theBandNo );
   if ( !myNoDataRangeList.isEmpty() )
   {
-    //QgsRasterBlock::DataType type = dataType( bandNo );
-    double myNoDataValue = noDataValue( bandNo );
-    size_t size = width * height;
+    double myNoDataValue = noDataValue( theBandNo );
+    size_t size = theWidth * theHeight;
     for ( size_t i = 0; i < size; i++ )
     {
       double value = block->value( i );
@@ -308,58 +363,6 @@ QString QgsRasterDataProvider::lastErrorFormat()
   return "text/plain";
 }
 
-QByteArray QgsRasterDataProvider::noValueBytes( int theBandNo )
-{
-  int type = dataType( theBandNo );
-  size_t size = QgsRasterBlock::typeSize( dataType( theBandNo ) ) / 8;
-  QByteArray ba;
-  ba.resize(( int )size );
-  char * data = ba.data();
-  double noval = noDataValue( theBandNo - 1 );
-  unsigned char uc;
-  unsigned short us;
-  short s;
-  unsigned int ui;
-  int i;
-  float f;
-  double d;
-  // TODO: define correct data types (typedef) like in GDAL
-  switch ( type )
-  {
-    case QgsRasterBlock::Byte:
-      uc = ( unsigned char )noval;
-      memcpy( data, &uc, size );
-      break;
-    case QgsRasterBlock::UInt16:
-      us = ( unsigned short )noval;
-      memcpy( data, &us, size );
-      break;
-    case QgsRasterBlock::Int16:
-      s = ( short )noval;
-      memcpy( data, &s, size );
-      break;
-    case QgsRasterBlock::UInt32:
-      ui = ( unsigned int )noval;
-      memcpy( data, &ui, size );
-      break;
-    case QgsRasterBlock::Int32:
-      i = ( int )noval;
-      memcpy( data, &i, size );
-      break;
-    case QgsRasterBlock::Float32:
-      f = ( float )noval;
-      memcpy( data, &f, size );
-      break;
-    case QgsRasterBlock::Float64:
-      d = ( double )noval;
-      memcpy( data, &d, size );
-      break;
-    default:
-      QgsLogger::warning( "GDAL data type is not supported" );
-  }
-  return ba;
-}
-
 bool QgsRasterDataProvider::hasPyramids()
 {
   QList<QgsRasterPyramid> myPyramidList = buildPyramidList();
@@ -401,7 +404,7 @@ QgsRasterBandStats QgsRasterDataProvider::bandStatistics( int theBandNo )
   int myNXBlocks = ( xSize() + xBlockSize() - 1 ) / xBlockSize();
   int myNYBlocks = ( ySize() + yBlockSize() - 1 ) / yBlockSize();
 
-  void *myData = CPLMalloc( xBlockSize() * yBlockSize() * ( dataTypeSize( theBandNo ) / 8 ) );
+  void *myData = CPLMalloc( xBlockSize() * yBlockSize() * ( dataTypeSize( theBandNo ) ) );
 
   // unfortunately we need to make two passes through the data to calculate stddev
   bool myFirstIterationFlag = true;
@@ -659,7 +662,7 @@ QgsRasterBandStats QgsRasterDataProvider::bandStatistics( int theBandNo,
   int myNXBlocks = ( myWidth + myXBlockSize - 1 ) / myXBlockSize;
   int myNYBlocks = ( myHeight + myYBlockSize - 1 ) / myYBlockSize;
 
-  void *myData = CPLMalloc( myXBlockSize * myYBlockSize * ( QgsRasterBlock::typeSize( dataType( theBandNo ) ) / 8 ) );
+  void *myData = CPLMalloc( myXBlockSize * myYBlockSize * ( QgsRasterBlock::typeSize( dataType( theBandNo ) ) ) );
 
   double myXRes = myExtent.width() / myWidth;
   double myYRes = myExtent.height() / myHeight;
@@ -935,7 +938,7 @@ QgsRasterHistogram QgsRasterDataProvider::histogram( int theBandNo,
   int myNXBlocks = ( myWidth + myXBlockSize - 1 ) / myXBlockSize;
   int myNYBlocks = ( myHeight + myYBlockSize - 1 ) / myYBlockSize;
 
-  void *myData = CPLMalloc( myXBlockSize * myYBlockSize * ( QgsRasterBlock::typeSize( dataType( theBandNo ) ) / 8 ) );
+  void *myData = CPLMalloc( myXBlockSize * myYBlockSize * ( QgsRasterBlock::typeSize( dataType( theBandNo ) ) ) );
 
   double myXRes = myExtent.width() / myWidth;
   double myYRes = myExtent.height() / myHeight;
diff --git a/src/core/raster/qgsrasterdataprovider.h b/src/core/raster/qgsrasterdataprovider.h
index 00b89c4ec24..abcf154908c 100644
--- a/src/core/raster/qgsrasterdataprovider.h
+++ b/src/core/raster/qgsrasterdataprovider.h
@@ -179,19 +179,12 @@ class CORE_EXPORT QgsRasterDataProvider : public QgsDataProvider, public QgsRast
     // TODO: Get the file masks supported by this provider, suitable for feeding into the file open dialog box
 
     /** Returns data type for the band specified by number */
-    virtual QgsRasterBlock::DataType dataType( int bandNo ) const
-    {
-      return srcDataType( bandNo );
-    }
+    virtual QgsRasterBlock::DataType dataType( int bandNo ) const = 0;
 
     /** Returns source data type for the band specified by number,
      *  source data type may be shorter than dataType
      */
-    virtual QgsRasterBlock::DataType srcDataType( int bandNo ) const
-    {
-      Q_UNUSED( bandNo );
-      return QgsRasterBlock::UnknownDataType;
-    }
+    virtual QgsRasterBlock::DataType srcDataType( int bandNo ) const = 0;
 
     /** Returns data type for the band specified by number */
     virtual int colorInterpretation( int theBandNo ) const
@@ -289,15 +282,8 @@ class CORE_EXPORT QgsRasterDataProvider : public QgsDataProvider, public QgsRast
     virtual void readBlock( int bandNo, QgsRectangle  const & viewExtent, int width, int height, void *data )
     { Q_UNUSED( bandNo ); Q_UNUSED( viewExtent ); Q_UNUSED( width ); Q_UNUSED( height ); Q_UNUSED( data ); }
 
-    /** read block of data using give extent and size */
-    // @note not available in python bindings
-    //virtual void readBlock( int bandNo, QgsRectangle  const & viewExtent, int width, int height, QgsCoordinateReferenceSystem theSrcCRS, QgsCoordinateReferenceSystem theDestCRS, void *data );
-
     /** Read block of data using given extent and size. */
-    // @note not available in python bindings
-    //virtual void *readBlock( int bandNo, QgsRectangle  const & extent, int width, int height );
-
-    virtual QgsRasterBlock *block( int bandNo, const QgsRectangle &extent, int width, int height );
+    virtual QgsRasterBlock *block( int theBandNo, const QgsRectangle &theExtent, int theWidth, int theHeight );
 
     /* Read a value from a data block at a given index. */
     virtual double readValue( void *data, int type, int index );
@@ -528,9 +514,6 @@ class CORE_EXPORT QgsRasterDataProvider : public QgsDataProvider, public QgsRast
     static QString makeTableCell( const QString & value );
     static QString makeTableCells( const QStringList & values );
 
-    /** \brief Set null value in char */
-    QByteArray noValueBytes( int theBandNo );
-
     /** Time stamp of data source in the moment when data/metadata were loaded by provider */
     virtual QDateTime timestamp() const { return mTimestamp; }
 
diff --git a/src/core/raster/qgsrasterfilewriter.cpp b/src/core/raster/qgsrasterfilewriter.cpp
index 4bd80573781..31aa477d17d 100644
--- a/src/core/raster/qgsrasterfilewriter.cpp
+++ b/src/core/raster/qgsrasterfilewriter.cpp
@@ -437,7 +437,7 @@ QgsRasterFileWriter::WriterError QgsRasterFileWriter::writeImageRaster( QgsRaste
   iter->setMaximumTileWidth( mMaxTileWidth );
   iter->setMaximumTileHeight( mMaxTileHeight );
 
-  //void* data = VSIMalloc( QgsRasterBlock::typeSize( inputDataType ) / 8 * mMaxTileWidth * mMaxTileHeight );
+  //void* data = VSIMalloc( QgsRasterBlock::typeSize( inputDataType ) * mMaxTileWidth * mMaxTileHeight );
   void* redData = VSIMalloc( mMaxTileWidth * mMaxTileHeight );
   void* greenData = VSIMalloc( mMaxTileWidth * mMaxTileHeight );
   void* blueData = VSIMalloc( mMaxTileWidth * mMaxTileHeight );
diff --git a/src/core/raster/qgsrasterlayer.cpp b/src/core/raster/qgsrasterlayer.cpp
index de20607a43f..59b5faa93db 100644
--- a/src/core/raster/qgsrasterlayer.cpp
+++ b/src/core/raster/qgsrasterlayer.cpp
@@ -2819,7 +2819,7 @@ QString QgsRasterLayer::projectionWkt()
 #if 0
 void *QgsRasterLayer::readData( int bandNo, QgsRasterViewPort *viewPort )
 {
-  int size = mDataProvider->dataTypeSize( bandNo ) / 8;
+  int size = mDataProvider->dataTypeSize( bandNo );
 
 #if 0
   QgsDebugMsg( "calling RasterIO with " +
diff --git a/src/core/raster/qgsrasterprojector.cpp b/src/core/raster/qgsrasterprojector.cpp
index d1aec58c8db..fa806bb392d 100644
--- a/src/core/raster/qgsrasterprojector.cpp
+++ b/src/core/raster/qgsrasterprojector.cpp
@@ -734,7 +734,7 @@ QgsRasterBlock * QgsRasterProjector::block( int bandNo, QgsRectangle  const & ex
     return outputBlock;
   }
 
-  size_t pixelSize = QgsRasterBlock::typeSize( mInput->dataType( bandNo ) ) / 8;
+  size_t pixelSize = QgsRasterBlock::typeSize( mInput->dataType( bandNo ) );
 
   if ( !outputBlock->reset( QgsRasterBlock::ARGB32_Premultiplied, width, height ) )
   {
diff --git a/src/gui/raster/qgsmultibandcolorrendererwidget.cpp b/src/gui/raster/qgsmultibandcolorrendererwidget.cpp
index 40fd9bc7e16..0448fa70bb9 100644
--- a/src/gui/raster/qgsmultibandcolorrendererwidget.cpp
+++ b/src/gui/raster/qgsmultibandcolorrendererwidget.cpp
@@ -35,8 +35,8 @@ QgsMultiBandColorRendererWidget::QgsMultiBandColorRendererWidget( QgsRasterLayer
     mMinMaxWidget = new QgsRasterMinMaxWidget( layer, this );
     mMinMaxWidget->setExtent( extent );
     layout()->addWidget( mMinMaxWidget );
-    connect( mMinMaxWidget, SIGNAL( load( int, double, double ) ),
-             this, SLOT( loadMinMax( int, double, double ) ) );
+    connect( mMinMaxWidget, SIGNAL( load( int, double, double, int ) ),
+             this, SLOT( loadMinMax( int, double, double, int ) ) );
 
     connect( mRedBandComboBox, SIGNAL( currentIndexChanged( int ) ),
              this, SLOT( onBandChanged( int ) ) );
@@ -191,7 +191,7 @@ void QgsMultiBandColorRendererWidget::onBandChanged( int index )
   mMinMaxWidget->setBands( myBands );
 }
 
-void QgsMultiBandColorRendererWidget::loadMinMax( int theBandNo, double theMin, double theMax )
+void QgsMultiBandColorRendererWidget::loadMinMax( int theBandNo, double theMin, double theMax, int theOrigin )
 {
   QgsDebugMsg( QString( "theBandNo = %1 theMin = %2 theMax = %3" ).arg( theBandNo ).arg( theMin ).arg( theMax ) );
 
diff --git a/src/gui/raster/qgsmultibandcolorrendererwidget.h b/src/gui/raster/qgsmultibandcolorrendererwidget.h
index bb5b958539c..2a0cb5c4da1 100644
--- a/src/gui/raster/qgsmultibandcolorrendererwidget.h
+++ b/src/gui/raster/qgsmultibandcolorrendererwidget.h
@@ -48,7 +48,7 @@ class GUI_EXPORT QgsMultiBandColorRendererWidget: public QgsRasterRendererWidget
     int selectedBand( int index = 0 );
 
   public slots:
-    void loadMinMax( int theBandNo, double theMin, double theMax );
+    void loadMinMax( int theBandNo, double theMin, double theMax, int theOrigin );
 
   private slots:
     //void on_mLoadPushButton_clicked();
diff --git a/src/providers/gdal/qgsgdalprovider.cpp b/src/providers/gdal/qgsgdalprovider.cpp
index e5838db5119..c50405a7953 100644
--- a/src/providers/gdal/qgsgdalprovider.cpp
+++ b/src/providers/gdal/qgsgdalprovider.cpp
@@ -378,10 +378,10 @@ void QgsGdalProvider::readBlock( int theBandNo, QgsRectangle  const & theExtent,
     QgsDebugMsg( QString( "transform : %1" ).arg( mGeoTransform[i] ) );
   }
 
-  int dataSize = dataTypeSize( theBandNo ) / 8;
+  int dataSize = dataTypeSize( theBandNo );
 
   // fill with null values
-  QByteArray ba = noValueBytes( theBandNo );
+  QByteArray ba = QgsRasterBlock::valueBytes( dataType( theBandNo ), noDataValue( theBandNo ) );
   char *nodata = ba.data();
   char *block = ( char * ) theBlock;
   for ( int i = 0; i < thePixelWidth * thePixelHeight; i++ )
@@ -835,7 +835,7 @@ QMap<int, void *> QgsGdalProvider::identify( const QgsPoint & point )
     // Outside the raster
     for ( int i = 1; i <= GDALGetRasterCount( mGdalDataset ); i++ )
     {
-      void * data = VSIMalloc( dataTypeSize( i ) / 8 );
+      void * data = VSIMalloc( dataTypeSize( i ) );
       QgsRasterBlock::writeValue( data, dataType( i ), 0, noDataValue( i ) );
       results.insert( i, data );
     }
@@ -884,7 +884,7 @@ QMap<int, void *> QgsGdalProvider::identify( const QgsPoint & point )
         }
       }
 #endif
-      int typeSize = dataTypeSize( i ) / 8;
+      int typeSize = dataTypeSize( i );
       void * tmpData = VSIMalloc( typeSize * width * height );
 
       CPLErr err = GDALRasterIO( gdalBand, GF_Read, col, row, width, height,
diff --git a/src/providers/grass/qgsgrassrasterprovider.cpp b/src/providers/grass/qgsgrassrasterprovider.cpp
index aa2e9d98d7a..f6801d9b5c0 100644
--- a/src/providers/grass/qgsgrassrasterprovider.cpp
+++ b/src/providers/grass/qgsgrassrasterprovider.cpp
@@ -128,7 +128,7 @@ QgsGrassRasterProvider::QgsGrassRasterProvider( QString const & uri )
   // memory, not too small to result in too many calls to readBlock -> qgis.d.rast
   // for statistics
   int cache_size = 10000000; // ~ 10 MB
-  mYBlockSize = cache_size / ( dataTypeSize( dataType( 1 ) ) / 8 ) / mCols;
+  mYBlockSize = cache_size / ( dataTypeSize( dataType( 1 ) ) ) / mCols;
   if ( mYBlockSize  > mRows )
   {
     mYBlockSize = mRows;
@@ -232,7 +232,7 @@ void QgsGrassRasterProvider::readBlock( int bandNo, int xBlock, int yBlock, void
   QgsDebugMsg( QString( "%1 bytes read from modules stdout" ).arg( data.size() ) );
   // byteCount() in Qt >= 4.6
   //int size = image->byteCount() < data.size() ? image->byteCount() : data.size();
-  int size = mCols * mYBlockSize * dataTypeSize( bandNo ) / 8;
+  int size = mCols * mYBlockSize * dataTypeSize( bandNo );
   QgsDebugMsg( QString( "mCols = %1 mYBlockSize = %2 dataTypeSize = %3" ).arg( mCols ).arg( mYBlockSize ).arg( dataTypeSize( bandNo ) ) );
   if ( size != data.size() )
   {
@@ -279,7 +279,7 @@ void QgsGrassRasterProvider::readBlock( int bandNo, QgsRectangle  const & viewEx
   QgsDebugMsg( QString( "%1 bytes read from modules stdout" ).arg( data.size() ) );
   // byteCount() in Qt >= 4.6
   //int size = image->byteCount() < data.size() ? image->byteCount() : data.size();
-  int size = pixelWidth * pixelHeight * dataTypeSize( bandNo ) / 8;
+  int size = pixelWidth * pixelHeight * dataTypeSize( bandNo );
   if ( size != data.size() )
   {
     QMessageBox::warning( 0, QObject::tr( "Warning" ),
@@ -439,7 +439,7 @@ QMap<int, void *> QgsGrassRasterProvider::identify( const QgsPoint & thePoint )
       QgsDebugMsg( "Cannot convert string to double" );
     }
   }
-  void * data = malloc( dataTypeSize( 1 ) / 8 );
+  void * data = malloc( dataTypeSize( 1 ) );
   QgsRasterBlock::writeValue( data, dataType( 1 ), 0, value );
 
   results.insert( 1, data );
diff --git a/src/providers/wcs/qgswcsprovider.cpp b/src/providers/wcs/qgswcsprovider.cpp
index 15abcc2dbda..8b35a6c1afe 100644
--- a/src/providers/wcs/qgswcsprovider.cpp
+++ b/src/providers/wcs/qgswcsprovider.cpp
@@ -503,7 +503,7 @@ void QgsWcsProvider::readBlock( int bandNo, QgsRectangle  const & viewExtent, in
   QgsDebugMsg( "Entered" );
 
   // TODO: set block to null values, move that to function and call only if fails
-  memset( block, 0, pixelWidth * pixelHeight * QgsRasterBlock::typeSize( dataType( bandNo ) ) / 8 );
+  memset( block, 0, pixelWidth * pixelHeight * QgsRasterBlock::typeSize( dataType( bandNo ) ) );
 
   // Requested extent must at least partialy overlap coverage extent, otherwise
   // server gives error. QGIS usually does not request blocks outside raster extent
@@ -579,7 +579,7 @@ void QgsWcsProvider::readBlock( int bandNo, QgsRectangle  const & viewExtent, in
       // Rotate counter clockwise
       // If GridOffsets With GeoServer,
       QgsDebugMsg( tr( "Rotating raster" ) );
-      int pixelSize = QgsRasterBlock::typeSize( dataType( bandNo ) ) / 8;
+      int pixelSize = QgsRasterBlock::typeSize( dataType( bandNo ) );
       QgsDebugMsg( QString( "pixelSize = %1" ).arg( pixelSize ) );
       int size = width * height * pixelSize;
       void * tmpData = malloc( size );
@@ -1643,7 +1643,7 @@ QMap<int, void *> QgsWcsProvider::identify( const QgsPoint & thePoint )
     // Outside the raster
     for ( int i = 1; i <= bandCount(); i++ )
     {
-      void * data = VSIMalloc( dataTypeSize( i ) / 8 );
+      void * data = VSIMalloc( dataTypeSize( i ) );
       QgsRasterBlock::writeValue( data, dataType( i ), 0, noDataValue( i ) );
       results.insert( i, data );
     }
@@ -1708,7 +1708,7 @@ QMap<int, void *> QgsWcsProvider::identify( const QgsPoint & thePoint )
   {
     GDALRasterBandH gdalBand = GDALGetRasterBand( mCachedGdalDataset, i );
 
-    void * data = VSIMalloc( dataTypeSize( i ) / 8 );
+    void * data = VSIMalloc( dataTypeSize( i ) );
     CPLErr err = GDALRasterIO( gdalBand, GF_Read, col, row, 1, 1,
                                data, 1, 1, ( GDALDataType ) mGdalDataType[i-1], 0, 0 );