Image resolution

[Lluís Garcia i Mestres]

Hi Jacob,

After few days out, I'm working again with my raster files. I don't
think I've solved. I'm getting the tif image and the tfw file from
grass. I've tried with the png and jpeg (better) but I'm losing image
quality. The image in the map file is the same than in the template.
Also I have tried with gtiff format but is not displayed in my
application, perhaps a jBox disavantge, but is created in the tmp
folder.

Any suggestion?

On 4/19/05, Lluís Garcia i Mestres <lluisgm at gmail.com> wrote:
> Thanks Jacob,
> 
> It looks that I get the same quality of image. Therefor I was using
> the same image size. With jpg format it seems correct the quality
> level.
> 
> Lluís
> 
> On 4/19/05, Jacob Delfos <jacob.delfos at maunsell.com> wrote:
> > Lluís,
> >
> > If you are using PNG, it is possible you only get 256 colours. Put these
> > statements in your mapfile (comment out your existing outputformat and
> > imagetype, if any), and check whether it gets any better:
> >
> > OUTPUTFORMAT
> >   NAME jpeg
> >   DRIVER "GD/JPEG"
> >   MIMETYPE "image/jpeg"
> >   IMAGEMODE RGB
> >   EXTENSION "jpg"
> >   FORMATOPTION "QUALITY=80"
> > END
> >
> > IMAGETYPE jpeg
> >
> > When I mentioned about changing the image size, I meant in your template. Do
> > you have an "<image" statement around your [img] parameter, and if so, is
> > the width of it the same as the mapimage in your mapfile?
> >
> > Regards,
> >
> > Jacob
> >
> > JACOB DELFOS
> > SPATIAL INFORMATION ANALYST
> > Maunsell Australia Pty Ltd
> > 629 Newcastle Street, WA 6007
> > PO Box 81, WA 6902
> > Leederville
> > Western Australia
> > ABN 20 093 846 925
> >
> > Tel     + 61 8 9281 6185
> > Fax    + 61 8 9281 6297
> > jacob.delfos at maunsell.com
> >
> >
> >
> > -----Original Message-----
> > From: Lluís Garcia i Mestres [mailto:lluisgm at gmail.com]
> > Sent: 19 April 2005 15:40
> > To: Jacob Delfos
> > Cc: MAPSERVER-USERS at lists.umn.edu
> > Subject: Re: [UMN_MAPSERVER-USERS] Image resolution
> >
> > I didn´t change the image size, it's the original from the tfw. My tif
> > is a composition of 6 RGB and is displayed as a raster layer in the
> > correct position. The resolution of the image and the map is the
> > same:72 dpi.
> >
> > The output format is png, and I think the problem should be there.
> >
> > Lluís
> >
> >
> > On 4/19/05, Jacob Delfos <jacob.delfos at maunsell.com> wrote:
> > > Is your map-image being displayed at its normal resolution, or did you
> > > specify a size for the image ( <img width=x height=x ) which does not
> > match
> > > your map-image size?
> > > Or are you by any chance using GIF as an output format? Or another format
> > > that is not rgb? Sometimes using indexed colour (8bit, 256 colours) can
> > > create the illusion of reduced resolution, because pixels of similar
> > colour
> > > get merged.
> > >
> > > Regards,
> > >
> > > Jacob
> > >
> > >
> > >
> > > -----Original Message-----
> > > From: UMN MapServer Users List [mailto:MAPSERVER-USERS at LISTS.UMN.EDU] On
> > > Behalf Of Lluís Garcia i Mestres
> > > Sent: 18 April 2005 22:04
> > > To: MAPSERVER-USERS at LISTS.UMN.EDU
> > > Subject: [UMN_MAPSERVER-USERS] Image resolution
> > >
> > > Hi
> > >
> > > I'm working with a tif file of 0,5 meter per pixel. I don't know why,
> > > when I check this tif out of mapserver the quality is greater than
> > > when I display it in my mapserver application. I´ve try with different
> > > resolution in the map file but the quality is still the same.
> > >
> > > Thanks
> > >
> > > Lluís
> > >
> >
>