Re: [udig-devel] GeoTiff - tif + tfw

[Andrea Antonello <andrea.antonello@xxxxxxxxx>]

> Hm, Jgrass bloating stuff is surely not the answer. 

Agreed

> Is current code for loading rasters house made or incorporated from another
> open source projects?

The image code is taken from the geotools project. It does much more
than just deal with images for their visualization ;)

> I do not know if there are any algorithms available out there for loading
> and viewing images like geotiff and world images (open source). Surely they
> are, but do not know, have not searched any. 
> Would there be any way to just load projection data into memory not images
> themselves (surely it is not a lot of data, even for a very large set of
> tiffs) for every image available in folder. uDig SDK can surely do the
> "math" thing of converting view windows coordinates into world coordinates
> and searching for right images through memory (just projection data), and
> then loading images with a same name. In a way "intersecting" coordinates of
> viewer extents with all the available from images and projecting them onto
> viewer if they appear in a result set.

That is the part I would be willing to code if there was an easy way to
deal with the images. There is a way in the new geotools versions, but
udig is for now some version behind, that is the problem.

> The main part is surely the imaging
> algorithm...This is probably the solution Andrea is talking about with
> geotools, or maybe I am just way off course.
>  
> Ok I must admit I am very green in uDig SDK and image algorithms. And aint
> saying it is a correct or easy solution or a solution at all :) , just
> "brainstorming" ...

Brainstroming is good for me, in te hope we can find a feasible
solution, better if for all of us :)

Ciao
Andrea




> 
> Zlatko.
> 
> -----Original Message-----
> From: udig-devel-bounces@xxxxxxxxxxxxxxxxxxxxx
> [mailto:udig-devel-bounces@xxxxxxxxxxxxxxxxxxxxx] On Behalf Of Andrea
> Antonello
> Sent: Wednesday, March 21, 2007 1:50 PM
> To: User-friendly Desktop Internet GIS
> Subject: Re: [udig-devel] GeoTiff - tif + tfw
> 
> Hi Zlatko, Jesse,
> I have tested the RC10 udig and regarding to tiffs and images it shows
> up the same problems: in both windows and linux the images are loaded
> with an extreme slowlyness and sometimes even do not load (the jpg at
> it's layer extent zoom).
> To try the same, I'm testing the thing with the jpg and tiff I put here
> (it is not a free dataset):
> www.hydrologis.com/testfiles/udigdata.tar.gz
> 
> The JGrass way is a bit a problem, since when imported into a JGrass
> workspace, the data are converted to GRASS raster format, which has a
> different compression mechanism, since is uses the tiff like a dataset
> and not an image. That way a tiff risks to explode. I have 300 megs of
> tiffs like the ones in the example and we realized that use them in a
> GRASS format, would make 10 giga out of it. So no way to handle them
> like that. The GRASS format is for analysis purposes.
> 
> I too need a mechanism to load automagically tiffs (let's say given a
> folder with tiffs and a file describing their position and so on) and
> would be very willing to code it into udig.
> 
> However our biggest and not in short time solvable problem is that tiffs
> and jpgs are not handled in the best way right now and that the new
> geotools with reviewed coverage is not here and now for udig.
> 
> So what I'm really thinking of, is to code the viewer with geotools,
> even if it makes me very, very sad, since I would like to put all of my
> efforts into udig and only udig! Since udig is THE desktop part, udig
> should be able to supply a configurable lightweight version of itself,
> like for axample arcexplore (not sure it is called like that :))
> 
> What do you think? Anyone any idea on how to solve that?
> 
> Ciao,
> Andrea
> 
> 
> 
> Zlatko Perenda probaly wrote:
>> Ok, maybe I will rephrase. JGrass plugin would be great. With all the
>> raster algorithms included in a plugin in udig, awsome. It would sure
>> cover all my needs, maybe Andrea would know little more about it.
>>
>> All I need is a possibilty to load appropriate tile (world file - tif +
>> tfw, ~4gb all together; I can convert them to geotiff) and project
>> shapes on them. So I would like to see loading of tifs handled by udig.
>> The question is how much time, of course we are talking estimations
>> only, will it take to write a Jgrass plugin? And to become available for
>> developing an application based on udig?
>>
>>  
>>
>> Oh, your feedback is really appreciated.
>>
>>  
>>
>> Zlatko.
>>
>>  
>>
>>  
>>
>> ------------------------------------------------------------------------
>>
>> *From:* udig-devel-bounces@xxxxxxxxxxxxxxxxxxxxx
>> [mailto:udig-devel-bounces@xxxxxxxxxxxxxxxxxxxxx] *On Behalf Of *Zlatko
>> Perenda
>> *Sent:* Wednesday, March 21, 2007 11:57 AM
>> *To:* 'User-friendly Desktop Internet GIS'
>> *Subject:* RE: [udig-devel] GeoTiff - tif + tfw
>>
>>  
>>
>> Hi,
>>
>>  
>>
>> Ok, if it is simple to fix then great.
>>
>>  
>>
>> So I can expect support for geotiff , or world files (tif + tfw),
>> somwhere in the upcoming fixes?
>>
>>  
>>
>> Thanks.
>>
>>  
>>
>> Zlatko.
>>
>>  
>>
>> ------------------------------------------------------------------------
>>
>> *From:* udig-devel-bounces@xxxxxxxxxxxxxxxxxxxxx
>> [mailto:udig-devel-bounces@xxxxxxxxxxxxxxxxxxxxx] *On Behalf Of *Jesse
>> Eichar
if you want to be called wise."
Skuggsja' - The King's mirror - 1240 Reykjavik
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