Re: Hard limits on output raster dimension

At 09:54 16/04/2018 -1000, Paul Wessel wrote:

>I wonder if there are any 32-bit count limitations on the raster image 
>output that ghostscript can produce? I.e., if I ask ghostscript to 
>rasterize an image plotted in PostScript using the image operator that has 
>dimensions NX * NY = NM pixels where NM > 2^32, is that supported.  I.e., 
>do you use 64-bit variables for counts (int64_t or size_t) in ghostscript?

The PostScript language is, basically, 32-bit, so if you exceed a signed 
32-bit integer at any point you are immediately into uncharted territory. 
Some values are represented internally by a fixed point representation, for 
performance reasons. Again exceeding that might lead to problems.

Beyond that, its impossible to tell from the limited amount of information 
supplied.


>I ask because I am getting an image that seems to suffer from 32/64 bit 
>issues.  Here is my image call (129600 by 64800 source image):
>
>V N 0 0 T 10800 5400 scale [/Indexed /DeviceRGB 1 <0000FFFF0000>] 
>setcolorspace
><< /ImageType 1 /Decode [0 1] /Width 129600 /Height 64800 /BitsPerComponent 1
>    /ImageMatrix [129600 0 0 -64800 0 64800] /DataSource currentfile 
> /ASCII85Decode filter /FlateDecode filter
> >> image
>G[BaQ!<E0#!.^11YO2Z'zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz
>.....

You haven't described the 'issues' and its not possible for us to 
investigate because you haven't given us enough to work with.

Please note that this mailing list is for questions regarding development 
of applications using Ghostscript (or development of Ghostscript itself), 
not bug reports or PostScript questions. If you think you have found a bug, 
please open a bug report and attach an example file.

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                     Ken