getBlock

Read specific block of blocked image

Since R2021a

Syntax

blockdata = getBlock(bim,blocksub)

blockdata = getBlock(bim,blocksub,'Level',L)

[blockdata,blockinfo] = getBlock(___)

Description

blockdata = getBlock(bim,blocksub) returns blockdata, the block specified by the subscripts in blocksub.

blockdata = getBlock(bim,blocksub,'Level',L) gets the specified block from the L'th level of the multiresolution blockedImage, bim. By default, L is 1.

[blockdata,blockinfo] = getBlock(___) also returns block metadata in blockinfo.

Examples

Read Block from Blocked Image

Create a blocked image and display it.

bim = blockedImage('tumor_091R.tif');
bigimageshow(bim,...
    'GridVisible','on', 'GridLevel', 1,...
    'GridLineWidth', 2, 'GridColor','k','GridAlpha',0.3);

Display the value of the SizeInBlocks property.

disp(bim.SizeInBlocks)

     5     6     1
     2     2     1
     1     1     1

Specify the block you want to read.

block = getBlock(bim, [3, 2, 1]);

Display the block.

imshow(block)   

Input Arguments

bim — Blocked image

blockedImage object

Blocked image, specified as a blockedImage object.

blocksub — Block subscript vector

integer-valued vector

Block subscript vector, specified as a 1-by-N integer-valued vector. Valid elements range from 1 to the corresponding element in the SizeInBlocks property.

Example: [3, 2, 1]

Output Arguments

blockdata — Block of pixels from blocked image

numeric array

Block of pixels from blocked image, returned as a numeric array. Partial blocks around the edges can be smaller than the BlockSize property.

blockinfo — Metadata of block of pixels

scalar struct

Metadata of block of pixels, returned as a scalar struct. The blockinfo struct contains these fields.

Field	Description
Start	Subscripts of the first element in blockdata
End	Subscripts of the last element in blockdata
Level	Image level

Version History

Introduced in R2021a