15 replies to this topic

[Cartogirl]

Hello all,

I have just over 10,000 points that are symbolized as circles. These points are areas of interest that need to be overlaid on a shaded relief image of the same area. The image then needs to be exported as a .tif/.tfw so that our client can import them into thier software for use. The problem is that when the final image is viewed the symbols no longer hold there shape as they become lost in the pixels (so to speak)
Is there a way to take the file and create a box or circle or some other shape based on the center node of each point?
As far as I know a .tif/.twf is all that can be used as the client uses the info associated with this file type to generate the data they need for their applications.

Cheers

Robyn

[Greg]

What software are you using?
If you are working with vectors, it could just be a resolution issue when converting to a raster tiff..

What is your client using the tiff for? I assume they need a tiff so they can georeference the tile?

[Cartogirl]

What software are you using?
If you are working with vectors, it could just be a resolution issue when converting to a raster tiff..

What is your client using the tiff for? I assume they need a tiff so they can georeference the tile?

I am working in ArcMap 9.2 and the client has their own software which is used for the navigaition of ships.
They take the tiff and run it through their own processes that allow them to use the data I supply.
I am dealing with two files that in the end are exported as one raster image. The point file contains vectors which are based on lat/long and a few other factors. Is there a way to change the resoultion of the points? when I export it I have the option of changing the resolution, as in dpi, but is that not for plotting purposes?

Cheers

Robyn

[Greg]

From what I understand, you would be best to export the point layer as a separate tiff at a much higher resolution (while keeping the same dimensions) then merge that tiff with your other layer. This should keep your point data clean & fine.

[Hans van der Maarel]

Hands up everybody who suspected I'd bring up FME here...

But yeah, if you can export the locations as points from ArcGIS, I can create circles with a specified radius on those locations, then send them back as a shapefile.

[Cartogirl]

Hands up everybody who suspected I'd bring up FME here...

But yeah, if you can export the locations as points from ArcGIS, I can create circles with a specified radius on those locations, then send them back as a shapefile.

I have one shp file with 1700+ points as a tester. is that what you would need one file with all the points or multiple files for each point?

[gregsd]

Hands up everybody who suspected I'd bring up FME here...

But yeah, if you can export the locations as points from ArcGIS, I can create circles with a specified radius on those locations, then send them back as a shapefile.

Can't you do a buffer in ArcGIS?

[Cartogirl]

Hands up everybody who suspected I'd bring up FME here...

But yeah, if you can export the locations as points from ArcGIS, I can create circles with a specified radius on those locations, then send them back as a shapefile.

Can't you do a buffer in ArcGIS?

What do you mean by doing a buffer? I know what a buffer is but what would that do for me? the issue really comes with final resolution...I think. :-)

[BioGeoMan]

If I am understanding the problem correctly, you need the points to be larger or some other shape so they do not blend into the pixels of the TIF file? Couldn't this be done by changing the symbology of the points in ArcMap or changing their size?

[sara.m.]

Is there a way to change the resoultion of the points? when I export it I have the option of changing the resolution, as in dpi, but is that not for plotting purposes?

Cheers

Robyn

DPI stands for dots per inch, and higher numbers will increase the resolution for both screen and print images. Maybe you're thinking of LPI which stands for Lines per inch, will is a resolution term used in offset printing.

I would increase the DPI (try doubling it) and see if that helps. Note that doubling your DPI will quadruple your file size (unless your image is compressed).

[gregsd]

Hands up everybody who suspected I'd bring up FME here...

But yeah, if you can export the locations as points from ArcGIS, I can create circles with a specified radius on those locations, then send them back as a shapefile.

Can't you do a buffer in ArcGIS?

What do you mean by doing a buffer? I know what a buffer is but what would that do for me? the issue really comes with final resolution...I think. :-)

Well, in MapInfo you can create buffers around points at a specified radius and I was just curious to see if you could or couldn't do this in ArcGIS, rather than having to use FME.

Sorry, it doesn't really help with your problem though

Greg.

[frax]

Robyn, I am not 100% sure exactly what you want to do - but isn't this mostly a limitation/problem with your client and their software/routine/processing.

If they have some custom software that can ONLY have TIFF as indata, I guess you (or they!) have to make the circles more visible in terms of contrast/size and/or tweak the overlay process.

Do they treat the TIFF as an image, or as a data grid? Maybe you could have pixel points in a one-channel TIFF, and the magnitude/size as the value? (normalized to 0-255).

[Cartogirl]

Robyn, I am not 100% sure exactly what you want to do - but isn't this mostly a limitation/problem with your client and their software/routine/processing.

If they have some custom software that can ONLY have TIFF as indata, I guess you (or they!) have to make the circles more visible in terms of contrast/size and/or tweak the overlay process.

Do they treat the TIFF as an image, or as a data grid? Maybe you could have pixel points in a one-channel TIFF, and the magnitude/size as the value? (normalized to 0-255).

They have their own proprietary format. We take a geotiff and create a bunch of “registration files” using an app that was created in-house, our client feeds that to their software vendor and their software vendor gives them back a data set that can be loaded into the software on the vessels. Which makes it very restricted that way.

We are still waiting to see if there is another way to give them just the point data and have them load it directly into thier program.

Thanks for all the help and suggestions

[Kalai Selvan]

Hi Cartogirl..

With your post i understand that WANT the point file to be converted into a tif file ---- COrrect..
And the problem is after converting them into an image file you are not able to view the points ---- Correct..
Well its not going to happen that way, coz as mentioned below you loose the resolution...

And you are talking about tif/tfw files... Tif is an image file and Tfw is a co-ordinates tranformation records, which tends to place into real world co-ordinates.. may be you need to work around the other way around..
Create an images file, do some sort of resolution setting in illustrator/photoshop and later goe-reference it and overlay over your shaded things..

Hope it makes some sense.

Thanks
GISGURU..


As far as I know a .tif/.twf is all that can be used as the client uses the info associated with this file type to generate the data they need for their applications.

Cheers

Robyn
[/quote]

[Cartogirl]

Hi Cartogirl..

With your post i understand that WANT the point file to be converted into a tif file ---- COrrect..
And the problem is after converting them into an image file you are not able to view the points ---- Correct..
Well its not going to happen that way, coz as mentioned below you loose the resolution...

And you are talking about tif/tfw files... Tif is an image file and Tfw is a co-ordinates tranformation records, which tends to place into real world co-ordinates.. may be you need to work around the other way around..
Create an images file, do some sort of resolution setting in illustrator/photoshop and later goe-reference it and overlay over your shaded things..

Hope it makes some sense.

Thanks
GISGURU..


As far as I know a .tif/.twf is all that can be used as the client uses the info associated with this file type to generate the data they need for their applications.

Cheers

Robyn

I have come ot the conclusion that what they want will likly not happen the way they want it to. I have spent the past few days trying everything I (and others) could think of to resolve this problem, without any true results. I am now waiting for what is now needed.
As for the tiff and tfw, both are generated as both are needed in the long run.

Thanks for all the help on this topic and Cheers

Robyn