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> > 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.

500KB is pretty big for firmware with limited memory. 
You'd have to allocate the whole thing and that would
take a lot.  

> > 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.

I dont think its because of the variables.  I use the
same codes.  The difference is the ENVIRONMENT, which
can be the host (PC) or integrated in the firmware. 
Of course, when I run it in the host, it works well
everytime because of the availability of memory.  

In TIFFReadRGBAStrip, what are the variables/buffers
that you allocate inside?  This API has the output and
input buffer as its parameters.  What else does it
need inside?  Does it allocate a very big amount of
memory inside?

Thanks.


AWARE [SYSTEMS]		Imaging expertise for the Delphi developer
		TIFF and LibTiff Mailing List Archive
	LibTiff Mailing List TIFF and LibTiff Mailing List Archive October 2005 Previous Thread Next Thread Previous by Thread Next by Thread Previous by Date Next by Date Contact The TIFF Mailing List Homepage This list is run by Frank Warmerdam Archive maintained by AWare Systems	Thread 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 2005.10.19 06:09 "Re: Resend: Black image", by Katrina Maramba > > 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. 500KB is pretty big for firmware with limited memory. You'd have to allocate the whole thing and that would take a lot. > > 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. I dont think its because of the variables. I use the same codes. The difference is the ENVIRONMENT, which can be the host (PC) or integrated in the firmware. Of course, when I run it in the host, it works well everytime because of the availability of memory. In TIFFReadRGBAStrip, what are the variables/buffers that you allocate inside? This API has the output and input buffer as its parameters. What else does it need inside? Does it allocate a very big amount of memory inside? Thanks.

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2005.10.19 06:09 "Re: Resend: Black image", by Katrina Maramba