Why does my TIF or TIFF image created by BLOCKPROC not open correctly outside of MATLAB in Image Processing Toolbox 7.0 (R2010a)?

I am using BLOCKPROC to perform "file to file" image processing on large TIF images.

fun = @(block_struct) imresize(block_struct.data,.5);

I = imread('penguin.tif');

%create and write with blockproc directly

blockproc(I,[20 20],fun,'Destination','TEST_blockproc.tif');

%create with blockproc and write with imwrite

I2=blockproc(I,[20 20],fun);

imwrite(I2,'TEST_imwrite.tif','tif')

%The image displays ok in MATLAB

imshow(I2) %just fine

%But if I open the file outside of MATLAB it may not open correctly

winopen('TEST_blockproc.tif') %fails

winopen('TEST_imwrite.tif')   %works

%Behavior may be different depending on your default TIF viewer that opens the image.

Answer 1

[MathWorks Support Team]

This may be expected behavior in Image Processing Toolbox 7.0 (R2010a) depending on your external TIF viewer.

BLOCKPROC, when used with the 'Destination' argument may create tiled TIF images. This is one of the advantages that allows large image file-to-file processing. If you wish to use an external application to view the TIF file, it must support tiled-tif images.