examples/Multimedia/ICL/ICLCodec/PngScanlineEncoder.h

/*
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modification, are permitted provided that the following conditions are met:

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  list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright notice,
  this list of conditions and the following disclaimer in the documentation
  and/or other materials provided with the distribution.
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  may be used to endorse or promote products derived from this software
  without specific prior written permission.

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AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Description:  
*/



#ifndef __PNGSCANLINEENCODER_H__
#define __PNGSCANLINEENCODER_H__

#include "PNGCodec.h"
#include "ImageUtils.h"

//
// These classes specialise the PNG writer to write
// scanlines with different bitmap depths/colour types
//

const TInt KPngScanlineFilterTypeLength = 1;

//
// CBitDepth1Encoder: specialised writer for 1bpp
//

const TInt KPngDepth1PixelsPerByte = 8;
const TInt KPngDepth1RoundUpValue = 7;
const TInt KPngDepth1ShiftValue = 1;

class CBitDepth1Encoder : public CPngWriteSubCodec
        {
private:
        virtual void DoConstructL();
        virtual TInt ScanlineBufferSize(TInt aPixelLength);
        virtual void DoEncode(const CFbsBitmap* aSource, const TInt aScanline,
                                        TUint8* aDataPtr, const TUint8* aDataPtrLimit);
        };

//
// CBitDepth2Encoder: specialised writer for 2bpp
//

const TInt KPngDepth2PixelsPerByte = 4;
const TInt KPngDepth2RoundUpValue = 3;
const TInt KPngDepth2ShiftValue = 2;
class CBitDepth2Encoder : public CPngWriteSubCodec
        {
private:
        virtual void DoConstructL();
        virtual TInt ScanlineBufferSize(TInt aPixelLength);
        virtual void DoEncode(const CFbsBitmap* aSource, const TInt aScanline,
                                        TUint8* aDataPtr, const TUint8* aDataPtrLimit);
        };

//
// CBitDepth4Encoder: specialised writer for 4bpp
//

const TInt KPngDepth4PixelsPerByte = 2;
const TInt KPngDepth4RoundUpValue = 1;
const TInt KPngDepth4ShiftValue = 4;
class CBitDepth4Encoder : public CPngWriteSubCodec
        {
private:
        virtual void DoConstructL();
        virtual TInt ScanlineBufferSize(TInt aPixelLength);
        virtual void DoEncode(const CFbsBitmap* aSource, const TInt aScanline,
                                        TUint8* aDataPtr, const TUint8* aDataPtrLimit);
        };

//
// CBitDepth8ColorType2Encoder: specialised writer for 8bpp, RGB colour
//
const TInt KPngDepth8RgbBytesPerPixel = 3;
class CBitDepth8ColorType2Encoder : public CPngWriteSubCodec
        {
private:
        virtual TInt ScanlineBufferSize(TInt aPixelLength);
        virtual void DoEncode(const CFbsBitmap* aSource, const TInt aScanline,
                                        TUint8* aDataPtr, const TUint8* aDataPtrLimit);
        };

//
// CBitDepth8Encoder: specialised writer for 8bpp
//

const TInt KPngDepth8PixelsPerByte = 1;
const TInt KPngDepth8ShiftValue = 0;
class CBitDepth8Encoder : public CPngWriteSubCodec
        {
private:
        virtual void DoConstructL();
        virtual TInt ScanlineBufferSize(TInt aPixelLength);
        virtual void DoEncode(const CFbsBitmap* aSource, const TInt aScanline,
                                        TUint8* aDataPtr, const TUint8* aDataPtrLimit);
        };

#endif // __PNGSCANLINEENCODER_H__

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