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2005.04.27 14:34 "How to find a Image is Bilevel", by Naveen Mamidi
2005.04.27 16:07 "Re: How to find a Image is Bilevel", by Joris Van Damme

2005.04.27 16:07 "Re: How to find a Image is Bilevel", by Joris Van Damme

Kumar,

> 1] How to find an image is only  Bilevel image  ( black and white ) ?

The SamplesPerPixel and BitsPerSample tag are the ones to consult. If both are
1, you've got a single bit per pixel image. Theoretically, this could also be a
palette image, though that is rare. If you want to exclude this possibility,
check also the PhotometricInterpretation flag, to see if it is either MinIsBlack
or MinIsWhite, and not Palette.

SamplesPerPixel:
http://www.awaresystems.be/imaging/tiff/tifftags/samplesperpixel.html

BitsPerSample:
http://www.awaresystems.be/imaging/tiff/tifftags/bitspersample.html
(note that LibTiff only supports all values being the same, and pretends this is
a single value tag to the upper layer)

PhotometricInterpretation
http://www.awaresystems.be/imaging/tiff/tifftags/photometricinterpretation.html


> 2]  I am able to read a raw and strip format image  using  TIFFReadScanline I
> do even want  to   READ TILED IMAGES line by line how do  i doso?

See http://www.remotesensing.org/libtiff/libtiff.html#Tiles


Joris Van Damme
info@awaresystems.be
http://www.awaresystems.be/
Download your free TIFF tag viewer for windows here:
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