[geotk] Reading and displaying tif file in geotoolkit

sorel johann johann.sorel at geomatys.fr
Fri Jan 6 07:09:20 EST 2012 

Yes the *-WF stands for WorldFile (so it will read the .prj and .tfw)
what is strange is that you don't see the TIFF-WF, since it's registered 
at the same time as other -WF .

about the DBF. we have classes to read such files but the current image 
readers do not use them.
It is not something usual, you are actually the first one to ask for 
support of a dbf aside the tiff.
Perhaps i'm wrong, you have any documents 
(specification,de-facto,recomandation,...) about a dbf related to image 
files ?


The way I would see it is a bit different, here is another approach :
Since the 'depth' information is not enough to know if it's a related to 
geoidal hight, sea level ... or if the value are upward or downward (200 
over or under the sea level ?).
Another approach would be to define a 3 or 4 dimension CRS in the prj 
file and have a 3 or 4 dimension matrix in the .tfw.
this way you could store image as usual and potential height or/and time 
informations.
We can already handle N dimension CRS definitions in the prj file so it 
should only requiere to fix the tfw parsing for N dimensions matrix.
The down side about it : the additional matrix values will not be handle 
by other applications, but anyway I don't think they read the dbf files, 
so it might not be a real problem.

johann



On 06/01/2012 10:51, Westgård Trond wrote:
> Hi Johann,
> And thank you for a quick answer (and a happy new year ;-) ).
>
> It is right, I use the Oasis-dialog to choose the filetype (and consequently to find the correct imagereader).
> For JPEG, BMP PNG, GIF I get two entries in the list of possible readers (example: GIF-WF and GIF), that must mean that the GIF-WF reader take for granted that there exists a "world file".
>
> But in the case of TIFF there comes only one alternative (the TIFF-WF alternative is missing in the list).
>
> The list is build by a call to:
>
>          final IIORegistry registry = IIORegistry.getDefaultInstance();
>          final Iterator<? extends ImageReaderWriterSpi>  it = registry.getServiceProviders(ImageReaderSpi.class, true);
>
> Then this iterator is "looped" to get a set of file-filters that maps to the correct service.
>
> Is there a missing reference to a .jar file in the pom.xml file ???
>
> A related question that Martin said he would test - read a "native" ESRI grid dataset. Such a set is stored in:
>
> ftp://ftp.imr.no/nmd/geomatys/
>
> Here is an example of a tiff-file with world and .prj file. But equally important an example where depth data is stored in the .dbf file, it is important for us to access such datasets to find out the depth at different locations and areas.
> Is there a reader for such a dataset ?
>
> Best Regards
>
> Trond
>
>
> -----Original Message-----
> From: geotoolkit-bounces at lists.osgeo.org [mailto:geotoolkit-bounces at lists.osgeo.org] On Behalf Of sorel johann
> Sent: 6. januar 2012 09:18
> To: Westgård Trond; geotoolkit at lists.osgeo.org
> Subject: Re: [geotk] Reading and displaying tif file in geotoolkit
>
> Hello trond,
>
> I guess you are using the widget in the oasis project.
> When you select the file, you must choose the correct Tiff reader in the file format combo box.
> there should be 3 differents readers available that handle tiff files.
>
> - Standard Java tiff reader - TIFF (*.tif, *.tiff)
> - WorldImage reader - TIFF-WF (*.tif, *.tiff)
> - GeoTiff reader - geotiff (*.tif, *.tiff)
>
> since you have the : Com.sun.media.imageioimpl.plugin.tiff.TIFFImageReader
> I think you selected the standard java reader, which doesn't read the projection informations in the tfw and prj which explains the transformation issue you had. You should select the World Image reader.
>
> I hope this helps.
>
> johann
>
>
> On 03/01/2012 09:55, Westgård Trond wrote:
>> Hello Martin,
>> And a happy new year to you too ;)
>>
>> What I use is not the classes directly, Johann has made calls to different file types in the "MapHandler" we have in our project.
>>
>> Both .jpg and .tif ends up in a call to the same static method (factory) in the geotk-coverage-3.x-SNAPSHOT library:
>>
>> In the "MapHandler" the class org.geotoolkit.coverage.io.CoverageIO is used like this:
>>
>>       public MapLayer createLayer(final File imageFile) {
>>           try {
>>               final String name = imageFile.getName();
>>               final GridCoverageReader reader = CoverageIO.createSimpleReader(imageFile);
>>               final MutableStyle style = new RandomStyleBuilder().createRasterStyle();
>>               final CoverageMapLayer layer = MapBuilder.createCoverageLayer(reader, style, name);
>>               layer.setDescription(SF.description(name, "")); // BREAK POINT HERE
>>               layer.setName(name);
>>               return layer;
>>           } catch (CoverageStoreException ex) {
>>               LOGGER.log(Level.WARNING, ex.getMessage(),ex);
>>           }
>>           return null;
>>       }
>>
>> The service found for the .tif file (debugs CoverageMapLayer's reader) is:
>>
>> Com.sun.media.imageioimpl.plugin.tiff.TIFFImageReader
>>
>> I suspect that this is a reader for geoTiff files because when I go to the source:
>>
>> http://www.java2s.com/Open-Source/Java-Document/6.0-JDK-Modules/Java-A
>> dvanced-Imaging/com/sun/media/imageioimpl/plugins/tiff/TIFFImageReader
>> .java.htm
>>
>> it looks to me that this reader looks for the information that is stored in a .tfw file is looked up within the .tif file itself.
>> And where is the .prj file used ?
>> So maybe it should be a check that if a .tfw file exists another ImageReader should be used ?
>>
>> But what I really want is a coverageReader that takes for instance the format that ESRI ArcMap use, then I get the extra information on the depth of each pixel for GEBCO depth data. I want to use this to find the depth at any point for example for a Oceanographic station. Then I need a reader that also goes into the attribute data stored in the .dbf file. An example of such a dataset you will find at:
>>
>> ftp://ftp.imr.no/nmd/geomatys/
>>
>> Here is the .tif, .tfw and .prj files in the example stored as well.
>>
>> Best Regards
>>
>> Trond
>>
>>
>>
>> -----Original Message-----
>> From: geotoolkit-bounces at lists.osgeo.org
>> [mailto:geotoolkit-bounces at lists.osgeo.org] On Behalf Of Martin
>> Desruisseaux
>> Sent: 2. januar 2012 16:52
>> To: geotoolkit at lists.osgeo.org
>> Subject: Re: [geotk] Reading and displaying tif file in geotoolkit
>>
>> Hello Trond
>>
>> I'm not sure if this is the cause, but there is a particular issue with the TIFF format to consider. Experience suggests that on some platforms, new codecs appear magically after an AWT window has been created, especially the "Standard TIFF image reader". This is independant of Geotk. For graphical applications, we recommend to invoke the following methods, in that order, after the Window has been created but before it is made visible (It is okay to invoke those methods more than once):
>>
>> org.geotoolkit.image.jai. setDefaultCodecPreferences();
>> org.geotoolkit.image.io.plugin.WorldFileImageReader.Spi.registerDefaul
>> ts(ServiceRegistry);
>>
>> The idea is to make sure that the "Standard TIFF image reader" is registered before to invoke the above initialization methods. Does it help?
>>
>>> A related questions: Does geotoolkit read the native ESRI-grid format
>>> (where we have the info catalog storing the attribute values) ?
>>>
>> Johann is in better position for this question...
>>
>>        Regards,
>>
>>            Martin
>>
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