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October 2005

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2005.10.13 11:03 "Black image", by Katrina Maramba
2005.10.13 11:12 "Resend: Black image", by Katrina Maramba
2005.10.17 21:44 "Re: Resend: Black image", by Al Eridani
2005.10.19 06:09 "Re: Resend: Black image", by Katrina Maramba

2005.10.17 21:44 "Re: Resend: Black image", by Al Eridani

On 10/13/05, katrina maramba wrote:
>
> Anyway, I have images from the camera Olympus C2500L
> that have these properties:
>
> Image Width = 1712
> Image Height = 1368
> StripByteCount = 523872
>
> Notice that its strip byte count is extremely large.

I don't think this strip byte count is large at all. With the image
dimensions you have quoted, it indicates a density of about 4.4 pixels 
per byte. As you give no indication of the number of colors of the 
image, compression used, etc. it is hard to make a guess.

> Anyway, when I run this image through my parser that
> calls the API TIFFReadRGBAStrip(), it SOMETIMES
> outputs an all-black image.  There's nothing in it,
> its all black.  Note that I indicated "sometimes".
> This is not reproducible all the time.

When a program gives different results for different runs, it is
almost always due to variables that are used before being 
initialized, so they contain just whatever their corresponding 
memory positions contained when they were allocated. Make sure
that you correctly initialize any variables (both scalars and arrays)
before using them.