[gs-devel] 'null' output device?

[Jeroen Janssen]

Hi everyone,

Thanks for all the ideas and suggestions.
When I'm back at work on monday I'll have a go at it and see what
works best for us.

For now, have a nice weekend.

Best regards,

Jeroen Janssen

On 8/31/07, Ray Johnston <Ray.Johnston at artifex.com> wrote:
> Jeroen,
>
> I recommend the 'bit' family of devices, bit, bitrgb, bitcmyk
> since these devices perform full rendering and can be configured
> with -dGrayValues=### for 1 bit per component (the default),
> 2 bit, 4 bit or 8 bit using -dGrayValues of 2, 4, 16, 256
> respectively.
>
> This device has a special internal check for the OutputFile
> file name being '/dev/null' or 'nul' and doesn't even make the
> 'fwrite' calls, thus avoiding even IO calls on the OS which can
> slow down the timing on some systems.
>
> Also the 'bit' family of devices are good because they perform no
> compression of the data. This timing closely mimics the timing when
> a bitmap is to be DMA'ed to a printer or is being 'displayed' directly
> from a buffer.
>
> I hope this helps.
>
> Best Regards,
> Ray Johnston
> ------------------------------------------------------------------------
>
> Jeroen Janssen wrote:
> > Hello,
> >
> > I'm going to run some tests that will result in lots of (bitmap)
> > output if I save it it to disk, so
> > I was wondering which device can be used to measure the 'raw'
> > performance of ghostscript rendering without saving the output to disk
> > (a 'null' output device?).
> >
> > I found the 'bounding box' device, but the source states:
> >  * One way to use a bounding box device is simply to include bbox.dev in the
> >  * value of DEVICE_DEVSn in the makefile.  This produces a free-standing
> >  * device named 'bbox' that can be selected in the usual way (-sDEVICE=bbox)
> >  * and that prints out the bounding box at each showpage or copypage without
> >  * doing any drawing.
> >
> > And (I think) this means that the bouding box will not perform the
> > actual drawing (and thus will not result in correct performance
> > results).
> >
> > Any ideas / suggestions?
> >
> > Thanks in advance,
> >
> > Jeroen Janssen
> > _______________________________________________
> > gs-devel mailing list
> > gs-devel at ghostscript.com
> > http://www.ghostscript.com/mailman/listinfo/gs-devel
> >
> >
>
>