Re: [OSGeo-Discuss] Israel and Romanian local chapter?
Hi Tyler: I'd certainly be pleased if there were more OSGeo activity here in Israel (and adoption of other open source software as well). However ESRI is very solidly implanted here. For the most part Israelis equate GIS with Arcview, and are not aware of alternatives. In my estimation, there's an uphill climb before reaching the level where we can start talking about a local chapter. Cheers, Micha Tyler Mitchell (OSGeo) wrote: Is anyone on this list interested in or working on local chapter work in Israel or Romania? ___ Discuss mailing list Discuss@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/discuss This mail was sent via Kinneret Mail-SeCure System. ___ Discuss mailing list Discuss@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/discuss
Re: [OSGeo-Discuss] Israel and Romanian local chapter?
Micha Silver ha scritto: ESRI is very solidly implanted here. For the most part Israelis equate GIS with Arcview, and are not aware of alternatives. In my estimation, there's an uphill climb before reaching the level where we can start talking about a local chapter. A more positive word: everybody thought the same just a few years ago, also here in Italy, but now things are definitely changed: our national reference INSPIRE implementations are largely based on GFOSS, and the Italian community is sizeable, mature, very active and vociferous. Things *can* change, and they do it rapidly. All the best. pc -- Paolo Cavallini, see: http://www.faunalia.it/pc ___ Discuss mailing list Discuss@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/discuss
RE: [OSGeo-Discuss] 'lossless' JPEG2000
François: When you say Mega-Images (- geo-sized images), just how big are you talking about? If you are in the 10-100GB range, I/LizardTech would be very interested in talking with you about the project, and also about supporting some of the geo metadata conventions. (Especially if you can do GB-sized data sets in less than 1GB of RAM without requiring the image be tiled!) ((Do you have any benchmark data you can share?) -mpg -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of François-Olivier Devaux Sent: Tuesday, February 26, 2008 12:47 AM To: discuss@lists.osgeo.org Subject: [OSGeo-Discuss] 'lossless' JPEG2000 Hi, Norman Vine has pointed to me this discussion about JPEG 2000, and I thought it might be interesting to give you a small overview on JPEG 2000 and present the OpenJPEG library on which we are working. FIELDS WHERE JPEG 2000 IS USED JPEG 2000 is becoming the reference in image compression for professional applications, where precision and flexibility is really necessary. The most know field using JPEG 2000 is Digital Cinema, where JPEG 2000 has been favored against MPEG2 and H.264. Linked to that field, High Quality Broadcast applications are also turning to JPEG 2000 because of its quality and scalability (low resolution versions can be extracted directly from a high resolution sequence without any re-encoding, and JPEG 2000 sequences are encoded in intra which eases video editing). More close to your field is Archiving, where we are feeling a trend to select JPEG 2000 as compression algorithm http://www.egov.vic.gov.au/index.php?env=-inlink/detail:m1780- 1-1-8-s-0:l-9669-1-1-- Medical imaging applications, where lossless compression is a important requirement, are also taking full advantage of JPEG 2000 remote browsing possibilities (with the JPIP protocol) http://www.earthtimes.org/articles/show/aware-inc-to-demonstra te-groundbreaking-medical-imaging-streaming-solution-at- himss08,290686.shtml - JPEG 2000 FEATURES The JPEG 2000 features that are interesting for GeoSpatial Imagery is of course the ability to achieve lossless compression, the scalability (lower quality and resolutions as well as spatial areas can be extracted from a compressed file, without the need of decompression the entire file), the high precision (most codecs can at least handle 16 bits per component, and up to 256 components) and the fact that the core coding system can be obtained free of charge. JPEG 2000 also has an inherent robustness higher than most compression schemes (JPEG, ...) and a great protocol to interactively remotely browse images called JPIP. - OPENJPEG OpenJPEG, is an open-source JPEG 2000 library. It has been very recently remodeled by the CNES and the french company CS to meet the requirements of applications using Mega-Images (- geo-sized images). Independent access to tiles has been improved, in order to increase the library encoding and decoding performances. This new version should be made accessible to users at the beginning of March. We are very happy of the performances of this new version, and are open to new contributions. Regarding other JPEG 2000 open source solutions in your field, the GDAL library has a JPEG 2000 module that is based on Jasper, which is a great library, but has unfortunately not evolved for the last years. - Cheers, François ___ Discuss mailing list Discuss@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/discuss ___ Discuss mailing list Discuss@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/discuss
RE: [OSGeo-Discuss] 'lossless' JPEG2000
IMO: Michael, Again, I don't pretend to be an expert on JPEG2000. However, I'd like to know more about the format for future reference. Does the wiki article at the following URL represent a good overview of the format? http://en.wikipedia.org/wiki/JPEG_2000 If it is accurate, there is a section that leads me to conclude that the format is not suitable for a lot of remotely sensed spatial imagery: snip Color components transformation Initially, images have to be transformed from the RGB color space to another color space, leading to three components that are handled separately. There are two possible choices:... /snip If this *is* the case, then I wouldn't be able to use the format to store multi and hyper spectral imagery (ignoring other JP2 issues). As to what format are we using currently:The source format that the data came in with appropriate Geophysics, ERMapper and in some cases Erdas Imagine conversions. What are we using in the future: To be determined, probably a database oriented solution. As to data corruption: Many image processing algorithims and processes result in data loss. The aim for most people is to understand what is acceptable and to minimise the corruption of their data. In our situation, some of the imagery may result from many millions of dollars spent in capture and processing. Much of it is irreplacable. All of it must be protected for future use. Bruce Notice: This email and any attachments may contain information that is personal, confidential, legally privileged and/or copyright.No part of it should be reproduced, adapted or communicated without the prior written consent of the copyright owner. It is the responsibility of the recipient to check for and remove viruses. If you have received this email in error, please notify the sender by return email, delete it from your system and destroy any copies. You are not authorised to use, communicate or rely on the information contained in this email. Please consider the environment before printing this email. ___ Discuss mailing list Discuss@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/discuss
RE: [OSGeo-Discuss] 'lossless' JPEG2000
I've not read the whole Wikipedia article, but the statement images have to be transformed from the RGB color space to another color space is indeed incorrect. Images that are 3-banded MAY be encoded with the YCC transform, but this is not required; images with some other number of bands do NOT undergo a color transform step. If you're using ERMapper (ECW) files now, you're already deep into the world of lossy transforms. Imagine files (.img) are lossless, I believe, so you're safe there. My offer to encode a few GB of sample data for you still holds :-) -mpg From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: Tuesday, February 26, 2008 2:12 PM To: OSGeo Discussions Subject: RE: [OSGeo-Discuss] 'lossless' JPEG2000 IMO: Michael, Again, I don't pretend to be an expert on JPEG2000. However, I'd like to know more about the format for future reference. Does the wiki article at the following URL represent a good overview of the format? http://en.wikipedia.org/wiki/JPEG_2000 If it is accurate, there is a section that leads me to conclude that the format is not suitable for a lot of remotely sensed spatial imagery: snip Color components transformation Initially, images have to be transformed from the RGB color space http://en.wikipedia.org/wiki/Color_space to another color space, leading to three components that are handled separately. There are two possible choices:... /snip If this *is* the case, then I wouldn't be able to use the format to store multi and hyper spectral imagery (ignoring other JP2 issues). As to what format are we using currently:The source format that the data came in with appropriate Geophysics, ERMapper and in some cases Erdas Imagine conversions. What are we using in the future: To be determined, probably a database oriented solution. As to data corruption: Many image processing algorithims and processes result in data loss. The aim for most people is to understand what is acceptable and to minimise the corruption of their data. In our situation, some of the imagery may result from many millions of dollars spent in capture and processing. Much of it is irreplacable. All of it must be protected for future use. Bruce Notice: This email and any attachments may contain information that is personal, confidential, legally privileged and/or copyright. No part of it should be reproduced, adapted or communicated without the prior written consent of the copyright owner. It is the responsibility of the recipient to check for and remove viruses. If you have received this email in error, please notify the sender by return email, delete it from your system and destroy any copies. You are not authorised to use, communicate or rely on the information contained in this email. Please consider the environment before printing this email. ___ Discuss mailing list Discuss@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/discuss
