adaptivethresholdcv

Syntax

R = adaptivethresholdcv(handle, max, method, type, blocksize, cvalue)

Inputs

handle

Handle of a single channel (grayscale) image or a 2D, real matrix.

Type: integer | mat

max

Non-zero max value applied to the affected pixels of handle.

Type: scalar

method

Adaptive threshold method. Valid values are:

0

Type cv::ADAPTIVE_THRESH_MEAN_C.

1

Type cv::ADAPTIVE_THRESH_GAUSSIAN_C

Type: integer

type

Threshold type. Valid values are:

0

Type cv::THRESH_BINARY.

1

Type cv::THRESH_BINARY_INV

Type: integer

blocksize

Size of pixel neighborhood.

Type: integer

cvalue

Constant subtracted from mean or weighted mean.

Type: scalar

Outputs

R

Handle of the output image.

Type: integer

Example

Apply adaptive threshold to the given image:

src = imreadcv('bird1.jpg', 0);
m = 100;
method = 1;
ttype = 0;
blocksize = 3;
constantval = 5;
R = adaptivethresholdcv(src, m, method, ttype, blocksize, constantval);

Apply adaptive threshold to remove the shadow on a book page:

imgoriginal = imreadcv('adaptivethresholdcv_fig3.png',1);
figure(1);
imshowcv(imgoriginal);

%Conver the image to gray scale
img = cvtcolorcv(imgoriginal, 6);
   
%Apply thresholding technique
thresh = adaptivethresholdcv(img, 255, 0,0, 199, 5)

figure(2);
imshowcv(thresh);