cv.StereoSGBM - mexopencv

Class for computing stereo correspondence using the semi-global block matching algorithm

The class implements the modified H. Hirschmuller algorithm [HH08] that differs from the original one as follows:

By default, the algorithm is single-pass, which means that you consider only 5 directions instead of 8. Set Mode='HH' in the contructor to run the full variant of the algorithm but beware that it may consume a lot of memory.
The algorithm matches blocks, not individual pixels. Though, setting BlockSize=1 reduces the blocks to single pixels.
Mutual information cost function is not implemented. Instead, a simpler Birchfield-Tomasi sub-pixel metric from [BT96] is used. Though, the color images are supported as well.
Some pre- and post- processing steps from K. Konolige algorithm cv.StereoBM are included, for example: pre-filtering (XSobel type) and post-filtering (uniqueness check, quadratic interpolation and speckle filtering).

Usage

bm = cv.StereoSGBM('MinDisparity',0, ...);
bm.BlockSize = ...;
disparity = bm.compute(left, right);

References

[HH08]:

Heiko Hirschmuller. "Stereo processing by semiglobal matching and mutual information". Pattern Analysis and Machine Intelligence, IEEE Transactions on, 30(2):328-341, 2008.

[BT96]:

Stan Birchfield and Carlo Tomasi. "A pixel dissimilarity measure that is insensitive to image sampling". Pattern Analysis and Machine Intelligence, IEEE Transactions on, 20(4):401-406, 1998.

Superclasses	handle
Sealed	false
Construct on load	false

BlockSize	Matched block size (SAD window size), default 3
Disp12MaxDiff	Maximum allowed difference (in integer pixel units) in the
MinDisparity	Minimum possible disparity value, default 0
Mode	Algorithm Mode, default 'SGBM'
NumDisparities	Maximum disparity minus minimum disparity, positive and divisble by
P1	first parameter controlling the disparity smoothness, default 0
P2	second parameter controlling the disparity smoothness, default 0
PreFilterCap	Truncation value for prefiltering image pixels, default 0
SpeckleRange	Maximum disparity variation within each connected component (when
SpeckleWindowSize	Maximum size of smooth disparity regions to consider their noise
UniquenessRatio	uniqueness ratio, Decides when to accept the computed disparity in
id	Object ID

	addlistener	Add listener for event.
	clear	Clears the algorithm state
	compute	Computes disparity map for the specified stereo pair
	delete	Destructor
	empty	Checks if algorithm object is empty
	eq	== (EQ) Test handle equality.
	findobj	Find objects matching specified conditions.
	findprop	Find property of MATLAB handle object.
	ge	>= (GE) Greater than or equal relation for handles.
	getDefaultName	Returns the algorithm string identifier
	gt	> (GT) Greater than relation for handles.
Sealed	isvalid	Test handle validity.
	le	<= (LE) Less than or equal relation for handles.
	listener	Add listener for event without binding the listener to the source object.
	load	Loads algorithm from a file or a string
	lt	< (LT) Less than relation for handles.
	ne	~= (NE) Not equal relation for handles.
	notify	Notify listeners of event.
	save	Saves the algorithm to a file