Jpeg Namespace Reference

A wrapper around the libjpeg provinding higher level C++ functions. More...

Functions
bool	ReadFileParams (const string &fileName, int &width, int &height, int &nChannels)
bool	DecompressFile (const string &fileName, unsigned char *dstBuffer, int &width, int &height, int &nChannels)
bool	DecompressBuffer (unsigned char *srcBuffer, int size, unsigned char *dstBuffer, int &width, int &height, int &bpp)
bool	CompressToFile (unsigned char *buffer, int width, int height, int bpp, const string &fileName, int quality=75)
bool	CompressToBuffer (unsigned char *srcBuffer, int width, int height, int bpp, unsigned char *dstBuffer, int &len, int quality)
TL_DLL bool	ReadFileParams (const std::string &fileName, int &width, int &height, int &nChannels)
TL_DLL bool	DecompressFile (const std::string &fileName, unsigned char *dstBuffer, int &width, int &height, int &nChannels)
TL_DLL bool	CompressToFile (unsigned char *buffer, int width, int height, int bpp, const std::string &fileName, int quality=75)

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Detailed Description

A wrapper around the libjpeg provinding higher level C++ functions.

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Function Documentation

TL_DLL bool Jpeg::CompressToBuffer	(	unsigned char *	srcBuffer,
		int	width,
		int	height,
		int	bpp,
		unsigned char *	dstBuffer,
		int &	len,
		int	quality = 75
	)

Compresses an image buffer to a JPEG image in memory

Parameters:

srcBuffer	address of the image in memory
width	width of image in pixels
height	height of image in pixels
bpp	number of bytes per pixel (1 or 3)
dstBuffer	pointer to a buffer to buffer to return the compressed data. The function assumes that it was allocated with enough space to hold the compressed data
len	returns the size of the compressed data. Initially this parameter should contain the size of the pre-allocated buffer
quality	image quality as a percentage

Returns:

true or false whether the compressing was successfull or not

bool Jpeg::CompressToFile	(	unsigned char *	buffer,
		int	width,
		int	height,
		int	bpp,
		const string &	fileName,
		int	quality = 75
	)

TL_DLL bool Jpeg::CompressToFile	(	unsigned char *	buffer,
		int	width,
		int	height,
		int	bpp,
		const std::string &	fileName,
		int	quality = 75
	)

Compresses an image buffer to a JPEG image file

Parameters:

buffer	address of the buffer that contains the image in memory
width	width of image in pixels
height	height of image in pixels
bpp	number of bytes per pixel (1 or 3)
fileName	name of the compressed file
quality	image quality as a percentage value

Returns:

true or false whether the compressing was successfull or not

TL_DLL bool Jpeg::DecompressBuffer	(	unsigned char *	srcBuffer,
		int	size,
		unsigned char *	dstBuffer,
		int &	width,
		int &	height,
		int &	bpp
	)

Decompresses a JPEG image buffer to a buffer in memory

Parameters:

srcBuffer	memory address containing jpeg compressed data
size	size in bytes of the jpeg compressed data
dstBuffer	pointer to a buffer to return the decompressed data. The function assumes that it was allocated with enough space to hold the decompressed data
width	return the number of columns of the data
height	return the number of lines of the data
bpp	return the number of bytes per pixel

Returns:

true or false whether the decompressing was successfull or not

TL_DLL bool Jpeg::DecompressFile	(	const std::string &	fileName,
		unsigned char *	dstBuffer,
		int &	width,
		int &	height,
		int &	nChannels
	)

Reads and decompresses a JPEG image file to a buffer in memory

Parameters:

fileName	name of the file
dstBuffer	pointer to a buffer to return the decompressed data. The function assumes that it was allocated with enough space to hold the decompressed data
width	returns the number of columns of the data
height	returns the number of lines of the data
nChannels	returns the number of bands, or channels, of the data

Returns:

true or false whether the decompressing was successfull or not

bool Jpeg::DecompressFile	(	const string &	fileName,
		unsigned char *	dstBuffer,
		int &	width,
		int &	height,
		int &	nChannels
	)

bool Jpeg::ReadFileParams	(	const string &	fileName,
		int &	width,
		int &	height,
		int &	nChannels
	)

TL_DLL bool Jpeg::ReadFileParams	(	const std::string &	fileName,
		int &	width,
		int &	height,
		int &	nChannels
	)

Reads the main informations about a JPEG image file

Parameters:

fileName	name of the file
width	return the number of columns of the data
height	return the number of lines of the data
nChannels	return the number of bands, or channels, of the data

Returns:

true or false whether the raster was imported successfully