Image Processing Toolbox User's Guide

bestblk

Determine block size for block processing

Syntax

• siz = bestblk([m n],k)
  [mb,nb] = bestblk([m n],k)
  

Description

siz = bestblk([m n],k) returns, for an m-by-n image, the optimal block size for block processing. k is a scalar specifying the maximum row and column dimensions for the block; if the argument is omitted, it defaults to 100. The return value siz is a 1-by-2 vector containing the row and column dimensions for the block.

[mb,nb] = bestblk([m n],k) returns the row and column dimensions for the block in mb and nb, respectively.

Algorithm

bestblk returns the optimal block size given m, n, and k. The algorithm for determining siz is

• If m is less than or equal to k, return m.
• If m is greater than k, consider all values between min(m/10,k/2) and k. Return the value that minimizes the padding required.

The same algorithm is then repeated for n.

Example

• siz = bestblk([640 800],72)
  
  siz =
  
      64    50
  

See Also

blkproc

axes2pix

blkproc

© 1994-2005 The MathWorks, Inc.