feat: Added cpp namespacev0.0.2

All functions and classes are now behind the cpp namespace `TehImage`

1 files changed, 309 insertions, 304 deletions

diff --git a/src/PNGImage.cpp b/src/PNGImage.cpp
index 7df04ad..9ba7404 100644
--- a/src/PNGImage.cpp
+++ b/src/PNGImage.cpp
@@ -15,385 +15,390 @@
 
 using std::cout, std::endl;
 
-PNGImage::PNGImage()
+namespace TehImage
 {
-	//cout << "Reader good" << endl;
-	REGISTER_CHUNK_READER(IHDR);
-	REGISTER_CHUNK_READER(iCCP);
-	REGISTER_CHUNK_READER(sRGB);
-	REGISTER_CHUNK_READER(eXIf);
-	REGISTER_CHUNK_READER(iDOT);
-	REGISTER_CHUNK_READER(pHYs);
-	REGISTER_CHUNK_READER(tIME);
-	REGISTER_CHUNK_READER(tEXt);
-	REGISTER_CHUNK_READER(IDAT);
-	REGISTER_CHUNK_READER(IEND);
 
-	//cout << "Chunk readers loaded" << endl;
+	PNGImage::PNGImage()
+	{
+		//cout << "Reader good" << endl;
+		REGISTER_CHUNK_READER(IHDR);
+		REGISTER_CHUNK_READER(iCCP);
+		REGISTER_CHUNK_READER(sRGB);
+		REGISTER_CHUNK_READER(eXIf);
+		REGISTER_CHUNK_READER(iDOT);
+		REGISTER_CHUNK_READER(pHYs);
+		REGISTER_CHUNK_READER(tIME);
+		REGISTER_CHUNK_READER(tEXt);
+		REGISTER_CHUNK_READER(IDAT);
+		REGISTER_CHUNK_READER(IEND);
 
+		//cout << "Chunk readers loaded" << endl;
 
-	idatData = nullptr;
-	idatDataSize = 0;
 
-	//cout << "PNG image initialised" << endl;
-}
-PNGImage::~PNGImage()
-{
-	free(idatData);
-	idatData = nullptr;
-	idatDataSize = 0;
-}
+		idatData = nullptr;
+		idatDataSize = 0;
 
-int PNGImage::readFromFile(std::string filename)
-{
-	std::unique_ptr<Reader> readerMem(new Reader(filename));
-	reader = readerMem.get();
-	
-	char signature[8];
-	uint8_t expected[] = {137, 80, 78, 71, 13, 10, 26, 10};
-	reader->readBytes(signature, 8);
-	if(strncmp(signature, (char*)expected, 8) != 0)
+		//cout << "PNG image initialised" << endl;
+	}
+	PNGImage::~PNGImage()
 	{
-		cout << "Not a PNG" << endl;
-		return 1;
+		free(idatData);
+		idatData = nullptr;
+		idatDataSize = 0;
 	}
 
-	while (readNextChunk()) {}
+	int PNGImage::readFromFile(std::string filename)
+	{
+		std::unique_ptr<Reader> readerMem(new Reader(filename));
+		reader = readerMem.get();
+	
+		char signature[8];
+		uint8_t expected[] = {137, 80, 78, 71, 13, 10, 26, 10};
+		reader->readBytes(signature, 8);
+		if(strncmp(signature, (char*)expected, 8) != 0)
+		{
+			cout << "Not a PNG" << endl;
+			return 1;
+		}
+
+		while (readNextChunk()) {}
 	
-	return 0;
-};
+		return 0;
+	};
 
-int PNGImage::writeToFile(std::string filename)
-{
-	cout << "Not implemented" << endl;
-	return 2;
-};
+	int PNGImage::writeToFile(std::string filename)
+	{
+		cout << "Not implemented" << endl;
+		return 2;
+	};
 
-bool PNGImage::readNextChunk()
-{
-	if(end)
-		return false;
-	uint32_t chunkSize = reader->readData<uint32_t>();
-	
-	char chunkType[4];
-	reader->readBytes(chunkType, 4);
-	std::string chunkName(chunkType, 4);
-	debug(
-		cout << "-------------" << endl;
-		cout << "|Chunk: " << chunkName << "|" << endl;
-		cout << "-------------" << endl;
-		);
-
-	if(chunkReaders.count(chunkName) == 0)
+	bool PNGImage::readNextChunk()
 	{
-		cout << "Chunk reader not found!!!" << endl;
-		reader->skipBytes(chunkSize + 4);
-		if(islower(chunkType[0]))
+		if(end)
+			return false;
+		uint32_t chunkSize = reader->readData<uint32_t>();
+	
+		char chunkType[4];
+		reader->readBytes(chunkType, 4);
+		std::string chunkName(chunkType, 4);
+		debug(
+			cout << "-------------" << endl;
+			cout << "|Chunk: " << chunkName << "|" << endl;
+			cout << "-------------" << endl;
+			);
+
+		if(chunkReaders.count(chunkName) == 0)
 		{
-			cout << "\tAble to skip chunk" << endl;
-			return true;
+			cout << "Chunk reader not found!!!" << endl;
+			reader->skipBytes(chunkSize + 4);
+			if(islower(chunkType[0]))
+			{
+				cout << "\tAble to skip chunk" << endl;
+				return true;
+			}
+			cout << "\tFatal error" << endl;
+			return false;
 		}
-		cout << "\tFatal error" << endl;
-		return false;
-	}
 
-	void(PNGImage::*chunkReader)(uint32_t chunkSize) = chunkReaders.find(chunkName)->second;
-	(this->*chunkReader)(chunkSize);
+		void(PNGImage::*chunkReader)(uint32_t chunkSize) = chunkReaders.find(chunkName)->second;
+		(this->*chunkReader)(chunkSize);
 
-	reader->skipBytes(4); // CRC
+		reader->skipBytes(4); // CRC
 		
-	return true;
-}
+		return true;
+	}
 
-DEFINE_CHUNK_READER(IHDR)
-{
-	width = reader->readData<uint32_t>();
-	height = reader->readData<uint32_t>();
-	bitDepth = reader->readData<uint8_t>();
-	colorType = reader->readData<uint8_t>();
-	compressionMethod = reader->readData<uint8_t>();
-	filterMethod = reader->readData<uint8_t>();
-	interlaceMethod = reader->readData<uint8_t>();
-	cout << "Width: " << width << ", Height: " << height << ", Bit depth: " << 0+bitDepth << ", Color type: " << 0+colorType << ", Compression method: " << 0+compressionMethod << ", Filter method: " << 0+filterMethod << ", Interlace method: " << 0+interlaceMethod << endl;
-
-	if(colorType != 2 && colorType != 6)
-		throw std::invalid_argument("Only color types 2 and 6 are supported");
-
-	if(bitDepth != 8)
-		throw std::invalid_argument("Only bit depth of 8 is supported");
-
-	switch(colorType)
+	DEFINE_CHUNK_READER(IHDR)
 	{
-	case 2: colorValues = 3; break;
-	case 6: colorValues = 4; break;
-	}
+		width = reader->readData<uint32_t>();
+		height = reader->readData<uint32_t>();
+		bitDepth = reader->readData<uint8_t>();
+		colorType = reader->readData<uint8_t>();
+		compressionMethod = reader->readData<uint8_t>();
+		filterMethod = reader->readData<uint8_t>();
+		interlaceMethod = reader->readData<uint8_t>();
+		cout << "Width: " << width << ", Height: " << height << ", Bit depth: " << 0+bitDepth << ", Color type: " << 0+colorType << ", Compression method: " << 0+compressionMethod << ", Filter method: " << 0+filterMethod << ", Interlace method: " << 0+interlaceMethod << endl;
+
+		if(colorType != 2 && colorType != 6)
+			throw std::invalid_argument("Only color types 2 and 6 are supported");
+
+		if(bitDepth != 8)
+			throw std::invalid_argument("Only bit depth of 8 is supported");
+
+		switch(colorType)
+		{
+		case 2: colorValues = 3; break;
+		case 6: colorValues = 4; break;
+		}
 
 
-	bpp = colorValues * (bitDepth/8);
+		bpp = colorValues * (bitDepth/8);
 
-	// unsigned long imageDataSize = width * height * bpp;
-	// imageDataSize = imageDataSize;
+		// unsigned long imageDataSize = width * height * bpp;
+		// imageDataSize = imageDataSize;
 
-	// cout << "Assigning " << imageDataSize << " bytes for image" << endl;
+		// cout << "Assigning " << imageDataSize << " bytes for image" << endl;
 
-	pixels = std::make_unique<Pixel[]>(width * height);
+		pixels = std::make_unique<Pixel[]>(width * height);
 	
 /*
-	Scanline<RGBPixel<uint8_t>>* lines = new Scanline<RGBPixel<uint8_t>> [height];
-	for(int i = 0; i < height; i++)
-	{
-		lines[i].pixels = new RGBPixel<uint8_t>[width];
-	}
-	imageData = (uint8_t*)lines;
+  Scanline<RGBPixel<uint8_t>>* lines = new Scanline<RGBPixel<uint8_t>> [height];
+  for(int i = 0; i < height; i++)
+  {
+  lines[i].pixels = new RGBPixel<uint8_t>[width];
+  }
+  imageData = (uint8_t*)lines;
 */
-}
+	}
 
-DEFINE_CHUNK_READER(iCCP)
-{
-	std::string profileName;
-	char c = reader->readByte();
-	chunkSize--;
-	while(c != 0)
+	DEFINE_CHUNK_READER(iCCP)
 	{
-		profileName.push_back(c);
-		c = reader->readByte();
+		std::string profileName;
+		char c = reader->readByte();
 		chunkSize--;
-	}
-	cout << profileName << endl;
-	uint8_t compresssionMethod = reader->readByte();
-	chunkSize--;
-	cout << 0+compresssionMethod << endl;
-	uint8_t CMF = reader->readByte();
-	uint8_t CM = CMF & 0b00001111;
-	uint8_t CINFO = (CMF & 0b11110000) >> 4;
-	chunkSize--;
-	uint8_t FLG = reader->readByte();
-	bool check = (CMF * 256 + FLG)%31 == 0;
-	bool FDICT = FLG & 0b00100000;
-	uint8_t FLEVEL = FLG & 0b11000000;
-	chunkSize--;
-	if(CM != 8)
-		cout << "Invalid CM: " << 0+CM << endl;
-	cout << 0+CM << ", " << 0+CINFO << ", " << (check?"Valid":"Failed checksum") << ", " << (FDICT?"Dict is present":"No dict present") << ", " << 0+FLEVEL << endl;
-	char compressedData[chunkSize - 4];
-	reader->readBytes(compressedData, chunkSize - 4);
-
-	char outData[1024];
-
-	ZLibInflator inflator;
-	inflator.decodeData((uint8_t*)compressedData, chunkSize - 4, (uint8_t*)outData, 1024);
-
-	cout << "iCCP not supported" << endl;
-	
-	uint32_t checkValue = reader->readData<uint32_t>();
+		while(c != 0)
+		{
+			profileName.push_back(c);
+			c = reader->readByte();
+			chunkSize--;
+		}
+		cout << profileName << endl;
+		uint8_t compresssionMethod = reader->readByte();
+		chunkSize--;
+		cout << 0+compresssionMethod << endl;
+		uint8_t CMF = reader->readByte();
+		uint8_t CM = CMF & 0b00001111;
+		uint8_t CINFO = (CMF & 0b11110000) >> 4;
+		chunkSize--;
+		uint8_t FLG = reader->readByte();
+		bool check = (CMF * 256 + FLG)%31 == 0;
+		bool FDICT = FLG & 0b00100000;
+		uint8_t FLEVEL = FLG & 0b11000000;
+		chunkSize--;
+		if(CM != 8)
+			cout << "Invalid CM: " << 0+CM << endl;
+		cout << 0+CM << ", " << 0+CINFO << ", " << (check?"Valid":"Failed checksum") << ", " << (FDICT?"Dict is present":"No dict present") << ", " << 0+FLEVEL << endl;
+		char compressedData[chunkSize - 4];
+		reader->readBytes(compressedData, chunkSize - 4);
 
-	//end = true;
-}
+		char outData[1024];
 
-DEFINE_CHUNK_READER(sRGB)
-{
-	renderingIntent = reader->readData<uint8_t>();
-	cout << "Rendering intent: " << 0+renderingIntent << endl;
-}
+		ZLibInflator inflator;
+		inflator.decodeData((uint8_t*)compressedData, chunkSize - 4, (uint8_t*)outData, 1024);
 
-DEFINE_CHUNK_READER(eXIf)
-{
-	char endian[4];
-	reader->readBytes(endian, 4);
-	for(int i = 0; i < 2; i++)
-	{
-		cout << endian[i];
+		cout << "iCCP not supported" << endl;
+	
+		uint32_t checkValue = reader->readData<uint32_t>();
+
+		//end = true;
 	}
-	for(int i = 2; i < 4; i++)
+
+	DEFINE_CHUNK_READER(sRGB)
 	{
-		cout << " " << 0+endian[i];
+		renderingIntent = reader->readData<uint8_t>();
+		cout << "Rendering intent: " << 0+renderingIntent << endl;
 	}
-	cout << endl;
-	char rest[chunkSize - 4];
-	reader->readBytes(rest, chunkSize - 4);
-	cout << std::hex;
-	for(int i = 0; i < chunkSize - 4; i++)
+
+	DEFINE_CHUNK_READER(eXIf)
 	{
-		cout << 0+rest[i] << " ";
+		char endian[4];
+		reader->readBytes(endian, 4);
+		for(int i = 0; i < 2; i++)
+		{
+			cout << endian[i];
+		}
+		for(int i = 2; i < 4; i++)
+		{
+			cout << " " << 0+endian[i];
+		}
+		cout << endl;
+		char rest[chunkSize - 4];
+		reader->readBytes(rest, chunkSize - 4);
+		cout << std::hex;
+		for(int i = 0; i < chunkSize - 4; i++)
+		{
+			cout << 0+rest[i] << " ";
+		}
+		cout << std::dec << endl;
 	}
-	cout << std::dec << endl;
-}
-
-DEFINE_CHUNK_READER(iDOT)
-{
-	cout << "!!! Ignoring iDOT !!!" << endl;
-	reader->skipBytes(chunkSize);
-}
-
-DEFINE_CHUNK_READER(pHYs)
-{
-	pixelsPerX = reader->readData<uint32_t>();
-	pixelsPerY = reader->readData<uint32_t>();
-	unit = reader->readData<uint8_t>();
-	cout << "Pixels per unit (x): " << pixelsPerX << ", Pixels per unit (y): " << pixelsPerY << ", unit: " << 0+unit << endl;
-}
 
-DEFINE_CHUNK_READER(tIME)
-{
-	year = reader->readData<uint16_t>();
-	month = reader->readData<uint8_t>();
-	day = reader->readData<uint8_t>();
-	hour = reader->readData<uint8_t>();
-	minute = reader->readData<uint8_t>();
-	second = reader->readData<uint8_t>();
-	cout << "Image last modified: " << 0+hour << ":" << 0+minute << ":" << 0+second << " " << 0+day << "-" << 0+month << "-" << 0+year << endl;
-}
+	DEFINE_CHUNK_READER(iDOT)
+	{
+		cout << "!!! Ignoring iDOT !!!" << endl;
+		reader->skipBytes(chunkSize);
+	}
 
-DEFINE_CHUNK_READER(tEXt)
-{
-	
-	std::string keyword;
-	char c = reader->readByte();
-	chunkSize--;
-	while(c != 0)
+	DEFINE_CHUNK_READER(pHYs)
 	{
-		keyword.push_back(c);
-		c = reader->readByte();
-		chunkSize--;
+		pixelsPerX = reader->readData<uint32_t>();
+		pixelsPerY = reader->readData<uint32_t>();
+		unit = reader->readData<uint8_t>();
+		cout << "Pixels per unit (x): " << pixelsPerX << ", Pixels per unit (y): " << pixelsPerY << ", unit: " << 0+unit << endl;
 	}
-	cout << keyword << endl;
-	std::string textString;
-	c = reader->readByte();
-	chunkSize--;
-	while(chunkSize > 0)
+
+	DEFINE_CHUNK_READER(tIME)
 	{
-		textString.push_back(c);
-		c = reader->readByte();
-		chunkSize--;
+		year = reader->readData<uint16_t>();
+		month = reader->readData<uint8_t>();
+		day = reader->readData<uint8_t>();
+		hour = reader->readData<uint8_t>();
+		minute = reader->readData<uint8_t>();
+		second = reader->readData<uint8_t>();
+		cout << "Image last modified: " << 0+hour << ":" << 0+minute << ":" << 0+second << " " << 0+day << "-" << 0+month << "-" << 0+year << endl;
 	}
-	textString.push_back(c);
-	cout << textString << endl;
-}
 
-DEFINE_CHUNK_READER(IDAT)
-{
-	if(idatDataSize == 0)
+	DEFINE_CHUNK_READER(tEXt)
 	{
-		uint8_t CMF = reader->readByte();
-		uint8_t CM = CMF & 0b00001111;
-		uint8_t CINFO = (CMF & 0b11110000) >> 4;
+	
+		std::string keyword;
+		char c = reader->readByte();
 		chunkSize--;
-		uint8_t FLG = reader->readByte();
-		bool check = (CMF * 256 + FLG)%31 == 0;
-		bool FDICT = FLG & 0b00000100;
-		uint8_t FLEVEL = FLG & 0b00000011;
+		while(c != 0)
+		{
+			keyword.push_back(c);
+			c = reader->readByte();
+			chunkSize--;
+		}
+		cout << keyword << endl;
+		std::string textString;
+		c = reader->readByte();
 		chunkSize--;
-		if(CM != 8)
-			cout << "Invalid CM: " << 0+CM << endl;
-		cout << 0+CM << ", " << 0+CINFO << ", " << (check?"Valid":"Failed checksum") << ", " << (FDICT?"Dict is present":"No dict present") << ", " << 0+FLEVEL << endl;
-		idatData = (uint8_t*)malloc(0);
+		while(chunkSize > 0)
+		{
+			textString.push_back(c);
+			c = reader->readByte();
+			chunkSize--;
+		}
+		textString.push_back(c);
+		cout << textString << endl;
 	}
 
-	idatData = (uint8_t *)realloc(idatData, idatDataSize + chunkSize);
-	reader->readBytes((char *)&idatData[idatDataSize], chunkSize);
-	idatDataSize += chunkSize;
+	DEFINE_CHUNK_READER(IDAT)
+	{
+		if(idatDataSize == 0)
+		{
+			uint8_t CMF = reader->readByte();
+			uint8_t CM = CMF & 0b00001111;
+			uint8_t CINFO = (CMF & 0b11110000) >> 4;
+			chunkSize--;
+			uint8_t FLG = reader->readByte();
+			bool check = (CMF * 256 + FLG)%31 == 0;
+			bool FDICT = FLG & 0b00000100;
+			uint8_t FLEVEL = FLG & 0b00000011;
+			chunkSize--;
+			if(CM != 8)
+				cout << "Invalid CM: " << 0+CM << endl;
+			cout << 0+CM << ", " << 0+CINFO << ", " << (check?"Valid":"Failed checksum") << ", " << (FDICT?"Dict is present":"No dict present") << ", " << 0+FLEVEL << endl;
+			idatData = (uint8_t*)malloc(0);
+		}
+
+		idatData = (uint8_t *)realloc(idatData, idatDataSize + chunkSize);
+		reader->readBytes((char *)&idatData[idatDataSize], chunkSize);
+		idatDataSize += chunkSize;
 
-	/*
-	unsigned long compressedSize = chunkSize - 4;
+		/*
+		  unsigned long compressedSize = chunkSize - 4;
 	
-	unsigned long imageDataSize = height * (width * 3 + 1);
-	cout << zlib.decodeData((uint8_t*)compressedData, compressedSize, imageData, imageDataSize) << endl;
-	//cout << (int)puff((unsigned char*)imageData, &imageDataSize, (const unsigned char*)compressedData, &compressedSize) << endl;
-	*/
+		  unsigned long imageDataSize = height * (width * 3 + 1);
+		  cout << zlib.decodeData((uint8_t*)compressedData, compressedSize, imageData, imageDataSize) << endl;
+		  //cout << (int)puff((unsigned char*)imageData, &imageDataSize, (const unsigned char*)compressedData, &compressedSize) << endl;
+		  */
 	
-	//uint32_t checkValue = reader->readData<uint32_t>();
+		//uint32_t checkValue = reader->readData<uint32_t>();
 
-	//end = true;
-}
+		//end = true;
+	}
 
-uint8_t paethPredictor(uint8_t a, uint8_t b, uint8_t c)
-{
-	int p = a + b - c;
-	int pa = abs(p - a);
-	int pb = abs(p - b);
-	int pc = abs(p - c);
-	if (pa <= pb && pa <= pc)
-		return a;
-	else if (pb <= pc)
+	uint8_t paethPredictor(uint8_t a, uint8_t b, uint8_t c)
+	{
+		int p = a + b - c;
+		int pa = abs(p - a);
+		int pb = abs(p - b);
+		int pc = abs(p - c);
+		if (pa <= pb && pa <= pc)
+			return a;
+		else if (pb <= pc)
 			return b;
-	else
-		return c;
-}
+		else
+			return c;
+	}
 
-DEFINE_CHUNK_READER(IEND)
-{
-	unsigned long imageDataSize = height * (width * bpp + 1);
-	uint8_t* pngImageData = new uint8_t[imageDataSize];
-	uint8_t* rawImage = new uint8_t[width * height * bpp];
-	cout << "My inflate " << zlib.decodeData(idatData, idatDataSize, pngImageData, imageDataSize) << endl;
-	end = true;
-	reader->close();
+	DEFINE_CHUNK_READER(IEND)
+	{
+		unsigned long imageDataSize = height * (width * bpp + 1);
+		uint8_t* pngImageData = new uint8_t[imageDataSize];
+		uint8_t* rawImage = new uint8_t[width * height * bpp];
+		cout << "My inflate " << zlib.decodeData(idatData, idatDataSize, pngImageData, imageDataSize) << endl;
+		end = true;
+		reader->close();
 
 #define imageDataIndex(x, y) rawImage[y*width*bpp + x]
 #define pngImageDataIndex(x, y) pngImageData[y*(width*bpp + 1) + x + 1]
 #define filterByte(y) pngImageDataIndex(-1, y)
 
-	for(int y = 0; y < height; y++)
-	{
-		for(int x = 0; x < width*bpp; x++)
+		for(int y = 0; y < height; y++)
 		{
-			if(filterByte(y) == 0)
-			{
-				imageDataIndex(x, y) = pngImageDataIndex(x, y);
-			}
-			else if(filterByte(y) == 1)
-			{
-				uint8_t sub = pngImageDataIndex(x, y);
-				uint8_t raw = (x>=bpp)?imageDataIndex((x-bpp), y):0;
-				imageDataIndex(x, y) = sub + raw;
-			}
-			else if(filterByte(y) == 2)
-			{
-				uint8_t up = pngImageDataIndex(x, y);
-				uint8_t prior = (y>=1)?imageDataIndex(x, (y-1)):0;
-				imageDataIndex(x, y) = up + prior;
-			}
-			else if(filterByte(y) == 3)
+			for(int x = 0; x < width*bpp; x++)
 			{
-				uint8_t avg = pngImageDataIndex(x, y);
-				uint8_t a = (x>=bpp)?imageDataIndex((x-bpp), y):0;
-				uint8_t b = (y>=1)?imageDataIndex(x, (y-1)):0;
-				imageDataIndex(x, y) = avg + std::floor((a + b)/2);
+				if(filterByte(y) == 0)
+				{
+					imageDataIndex(x, y) = pngImageDataIndex(x, y);
+				}
+				else if(filterByte(y) == 1)
+				{
+					uint8_t sub = pngImageDataIndex(x, y);
+					uint8_t raw = (x>=bpp)?imageDataIndex((x-bpp), y):0;
+					imageDataIndex(x, y) = sub + raw;
+				}
+				else if(filterByte(y) == 2)
+				{
+					uint8_t up = pngImageDataIndex(x, y);
+					uint8_t prior = (y>=1)?imageDataIndex(x, (y-1)):0;
+					imageDataIndex(x, y) = up + prior;
+				}
+				else if(filterByte(y) == 3)
+				{
+					uint8_t avg = pngImageDataIndex(x, y);
+					uint8_t a = (x>=bpp)?imageDataIndex((x-bpp), y):0;
+					uint8_t b = (y>=1)?imageDataIndex(x, (y-1)):0;
+					imageDataIndex(x, y) = avg + std::floor((a + b)/2);
 				
-			}
-			else if(filterByte(y) == 4)
-			{
-				uint8_t a = (x>=bpp)?imageDataIndex((x-bpp), y):0;
-				uint8_t b = (y>=1)?imageDataIndex(x, (y-1)):0;
-				uint8_t c = (x>=bpp && y>=1)?imageDataIndex((x-bpp), (y-1)):0;
-				uint8_t paeth = pngImageDataIndex(x, y);
-				uint8_t predictor = paethPredictor(a, b, c);
-				imageDataIndex(x, y) = paeth + predictor;
-			}
-			else
-			{
-				cout << "No method for filter type: " << (int)filterByte(y) << ", row: " << y << endl;
-				throw std::invalid_argument("Filter type not implemented");
+				}
+				else if(filterByte(y) == 4)
+				{
+					uint8_t a = (x>=bpp)?imageDataIndex((x-bpp), y):0;
+					uint8_t b = (y>=1)?imageDataIndex(x, (y-1)):0;
+					uint8_t c = (x>=bpp && y>=1)?imageDataIndex((x-bpp), (y-1)):0;
+					uint8_t paeth = pngImageDataIndex(x, y);
+					uint8_t predictor = paethPredictor(a, b, c);
+					imageDataIndex(x, y) = paeth + predictor;
+				}
+				else
+				{
+					cout << "No method for filter type: " << (int)filterByte(y) << ", row: " << y << endl;
+					throw std::invalid_argument("Filter type not implemented");
+				}
 			}
 		}
-	}
 
 #undef imageDataIndex
 #undef pngImageDataIndex
 #undef filterByte
 
-	for(int y = 0; y < height; y++)
-	{
-		for(int x = 0; x < width; x++)
+		for(int y = 0; y < height; y++)
 		{
-			(*this)[x, y].r = rawImage[(y*width + x)*colorValues];
-			(*this)[x, y].g = rawImage[(y*width + x)*colorValues + 1*bitDepth/8];
-			(*this)[x, y].b = rawImage[(y*width + x)*colorValues + 2*bitDepth/8];
-			(*this)[x, y].a = (colorValues == 4)?rawImage[(y*width + x)*colorValues]:255;
+			for(int x = 0; x < width; x++)
+			{
+				(*this)[x, y].r = rawImage[(y*width + x)*colorValues];
+				(*this)[x, y].g = rawImage[(y*width + x)*colorValues + 1*bitDepth/8];
+				(*this)[x, y].b = rawImage[(y*width + x)*colorValues + 2*bitDepth/8];
+				(*this)[x, y].a = (colorValues == 4)?rawImage[(y*width + x)*colorValues]:255;
 			
+			}
 		}
-	}
 	
-	delete [] pngImageData;
-	delete [] rawImage;
+		delete [] pngImageData;
+		delete [] rawImage;
+	}
+
 }