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TIFF and LibTiff Mail List Archive

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2005.05.25 12:58 "Re: [Tiff] Help me on convert from TIFF 24 bit or 8 bit grayscale tobilevel image", by Joris
2005.05.25 12:20 "[Tiff] Help me on convert from TIFF 24 bit or 8 bit grayscale to bilevel image", by AnhTuan Nguyen
2005.05.25 13:27 "Re: [Tiff] Help me on convert from TIFF 24 bit or 8 bit grayscale tobilevel image", by Nguyen Anh Tuan
2005.05.25 16:29 "Re: [Tiff] Help me on convert from TIFF 24 bit or 8 bit grayscaletobilevel image", by Joris

2005.05.25 12:58 "Re: [Tiff] Help me on convert from TIFF 24 bit or 8 bit grayscale tobilevel image", by Joris

Tuan,

> I'm a newer on this mailing list. Now I'm developping my image processing program. I have tried converted a TIFF 24 bit RGB or 8 bit grayscale to bilevel TIFF image, but i'm fail. Please help me deal with the issue.

Strictly speaking, this is off-topic. It's not a TIFF issue, but a general imaging issue.

You probably want to 'dither'. Dithering is the art of taking the error after rounding one pixel, to the next, so that errors in neighbouring pixels compensate eachother, and thus the overall 'impression' the eye gets from a block of neighbouring pixels is quite accurate despite huge individual errors in individual pixels.

Google on 'dither', there are a number of different techniques, each having some advantages and some dissadvantages.

Joris Van Damme
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