Linear time MSER implementation
[Image processing]

Classes and functions that implement linear time MSER algorithm. More...

Classes
class	QVMSER
	Maximally stable extremal region datatype. More...
Functions
QList< QVPolyline >	getLTMSERContours (QVImage< uChar > &input_image, const int minArea=20, const int maxArea=100000, const int delta=15, const float delta_threshold=0.03, const unsigned int downscaling=1)
	Obtains the MSER (linear time MSER) contours from a QVImage<uChar>.
QList< QVMSER >	getLTMSER (QVImage< uChar > &input_image, const int minArea=20, const int maxArea=100000, const int delta=15, const float delta_threshold=0.03, const unsigned int downscaling=1)
	Obtains the extracted MSER regions (QVMSER structures) using linear time MSER on a QVImage<uChar>
QList< QVPolyline >	getLTMSERContours (QVImage< uChar > &input_image, QList< QVMSER > mser_list)
	Obtains the MSER (linear time MSER) contours corresponding to a list of given QVMSER structures.

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Detailed Description

Classes and functions that implement linear time MSER algorithm.

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Function Documentation

QList<QVPolyline> getLTMSERContours	(	QVImage< uChar > &	input_image,
		const int	minArea = 20,
		const int	maxArea = 100000,
		const int	delta = 15,
		const float	delta_threshold = 0.03,
		const unsigned int	downscaling = 1
	)

Obtains the MSER (linear time MSER) contours from a QVImage<uChar>.

The obtained MSER are in fact only the MSER+ (regions darker than background). If you want to detect MSER- regions, you should manually negate the input image (using Not function, for example), and calling again this function. Besides the typical parameters (minArea, maxArea, delta and delta_threshold; see paper), the last parameter to this function allows to downscale the input image used to obtain the (intermediate) MSER seeds, though the final seed position values are returned rescaled back to the original size. This can be used to accelerate seed extraction (of course at the cost of discarding smaller regions) without loosing precision when obtaining the rest of contours (as the seeds are used on the original image, instead of the rescaled one, thus preserving original precission in the borders of each contour -in fact, this is not completely true, because the final threshold is also affected by downscaling; anyway, for many applications the approximation should behave acceptably-).

Parameters:

	input_image	Image to obtain MSERs from.
	minArea	Minimum area for each MSER.
	maxArea	Maximal area for each MSER.
	delta	Delta value for MSER algorithm (see paper).
	delta_threhold	Delta threshold value for MSER algorithm.
	downscaling	Initial scaling performed of input image; by default, no downscaling is performed

Returns:

output_contours List of output contours corresponding to detected MSERs.

See also:

getLTMSER getLTMSERContours(QVImage<uChar>&,QList<QVMSER>);

Definition at line 242 of file qvltmser.cpp.

QList<QVMSER> getLTMSER	(	QVImage< uChar > &	input_image,
		const int	minArea = 20,
		const int	maxArea = 100000,
		const int	delta = 15,
		const float	delta_threshold = 0.03,
		const unsigned int	downscaling = 1
	)

Obtains the extracted MSER regions (QVMSER structures) using linear time MSER on a QVImage<uChar>

This function differs from the one above in that it does not compute the corresponding contours.

Parameters:

	input_image	Image to obtain MSERs from.
	minArea	Minimum area for MSER.
	maxArea	Maximal area for MSER.
	delta	Delta value for MSER algorithm (see paper).
	delta_threhold	Delta threshold value for MSER algorithm.
	downscaling	Initial scaling performed of input image; by default, no downscaling is performed

Returns:

List of output obtained QVMSER structures.

See also:

getLTMSERContours(QVImage<uChar> &,const int,const int,const int,const float,const unsigned int) getLTMSERContours(QVImage<uChar> &,QList<QVMSER>) QVMSER

Definition at line 62 of file qvltmser.cpp.

Referenced by getLTMSERContours().

QList<QVPolyline> getLTMSERContours	(	QVImage< uChar > &	input_image,
		QList< QVMSER >	mser_list
	)

Obtains the MSER (linear time MSER) contours corresponding to a list of given QVMSER structures.

This function can be called with the output of the above function to get the list of contours corresponding to a list of given QVMSER structures.

Parameters:

	input_image	Image to obtain MSERs from.
	minArea	Minimum area for MSER.
	maxArea	Maximal area for MSER.
	delta	Delta value for MSER algorithm (see paper).
	delta_threhold	Delta threshold value for MSER algorithm.

Returns:

List of output contours obtained from the input QVMSER structures.

See also:

getLTMSERContours(QVImage<uChar> &,const int,const int,const int,const float,const unsigned int) getLTMSER QVMSER

Definition at line 228 of file qvltmser.cpp.

Referenced by getLTMSERContours().