From nuevos@hp400.ccu.uniovi.es Mon Sep 13 07:01:01 1993 X-VM-VHeader: ("From:" "Sender:" "Resent-From" "To:" "Apparently-To:" "Cc:" "Subject:" "Date:" "Resent-Date:") nil X-VM-Bookmark: 1 Status: RO X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] [nil nil nil nil nil nil nil nil nil nil nil nil "^From:" nil nil nil]) Newsgroups: sci.data.formats Organization: Universidad de Oviedo Nntp-Posting-Host: hp400.ccu.uniovi.es X-Newsreader: TIN [version 1.2 PL0] From: nuevos@hp400.ccu.uniovi.es (Raul y Quique) Subject: Re: GIF Date: 13 Sep 93 09:23:16 +0100 Schr›der, Ragnar 7-94 (RAGNAR-S@gribb.hsr.no) wrote: : Greetings, : could anyone please help me get the GIF algorithm? : I have a GIF file that has been corrupted, and need to understand the : format in order to repair it. : This is all for fun, so please don't put too much effort in. You can get the GIF file format from telva.ccu.uniovi.es (156.35.31.31): /pub/graphics/Image/Format. And algorithms from ImageMagick, xli, xloadimage ... ( also from telva and other sites, try archie ). Cheers. ================================================================= = Raul Rivero = = LabCAD = nuevos@hp400.ccu.uniovi.es = = Mathematics Dept. = adm@hp400.ccu.uniovi.es = = University of Oviedo = rivero@oboe.etsiig.uniovi.es = = ------------------------------------------------------------- = = " If architects built buildings the way programmers write = = programs the first woodpecker that came along would destroy = = civilization " - Murphy's Laws of Computers. = ================================================================= From dean@phobos.cira.colostate.edu Tue Sep 14 21:50:16 1993 Newsgroups: sci.data.formats From: dean@phobos.cira.colostate.edu Subject: Re: TIFF format Date: Tue, 14 Sep 1993 18:59:44 GMT Reply-To: dean%phobos.dnet@sirius.cira.colostate.edu Nntp-Posting-Host: sol.cira.colostate.edu Organization: Colorado State Univ, CIRA Check out the newsgroup alt.graphics.pixutils FAQ. It will list several public domian packages to convert one format to another. For a PC I would use the PBMplus utilities to convert TIFF -> raw data. Kelly Dean From nuevos@hp400.ccu.uniovi.es Wed Sep 15 10:24:27 1993 Newsgroups: sci.data.formats Subject: Re: TIFF format From: nuevos@hp400.ccu.uniovi.es (Raul y Quique) Date: 15 Sep 93 09:48:17 +0100 Organization: Universidad de Oviedo Nntp-Posting-Host: hp400.ccu.uniovi.es X-Newsreader: TIN [version 1.2 PL0] Bi Mi - ang (bimi@iss.nus.sg) wrote: : Hello, everyone, : I am looking for the PC software which can convert image : data between TIFF and raw data format. Any kind of suggestion : would be appreciated. You can get our software from telva.ccu.uniovi.es(156.35.31.31): /uniovi/mathdept/stc/PC/lugbin.zip. You'll canb convert from/to gif, tiff, tga, alias, Utah RLE, ... and raw. Enjoy. ================================================================= = Raul Rivero = = LabCAD = nuevos@hp400.ccu.uniovi.es = = Mathematics Dept. = adm@hp400.ccu.uniovi.es = = University of Oviedo = rivero@oboe.etsiig.uniovi.es = = ------------------------------------------------------------- = = " If architects built buildings the way programmers write = = programs the first woodpecker that came along would destroy = = civilization " - Murphy's Laws of Computers. = ================================================================= From giovanne@ccrs.emr.ca Thu Sep 30 00:02:02 1993 Newsgroups: sci.data.formats From: giovanne@ccrs.emr.ca (Mark Giovannetti) Subject: Some comments on the CEOS Format Nntp-Posting-Host: nova.ccrs.emr.ca Organization: Canada Centre for Remote Sensing Date: Wed, 29 Sep 1993 22:32:10 GMT Lessons Learned from the CEOS Format This article summarizes the lessons learned from using and supporting the CEOS (Committee on Earth Observation Satellites) Computer Compatible Tape (CCT) Format at the Canada Centre for Remote Sensing (CCRS). A little background may be necessary. CCRS has been active in the design and specification of the CEOS CCT Format since its inception around 1980 and still maintains it as the standard for satellite and airborne imagery data exchange. CCRS's main use of the standard is for data distribution to research scientists who are our main user group. Almost all of the products available from CCRS or through CCRS are sent in the CEOS format in one form or another on 9-track tape. Exabyte tapes have also been adopted in the last few years. Pros: - The format was designed around tape media and this has the advantage of being easily shipped to the user. However with the advent of the current and future network technology, it will be necessary to include this in the design considerations for a future formatting system. - The format contains all the information required to successfully analyze, correct and interpret the imagery data. - The overall logical structure of the format is simple to grasp from a tape file point of view. - All Canadian data downlink processing facilities produce products conforming to the CEOS standard. These products can range from RAW data to highly processed scenes of imagery and are supported in the CEOS format document for a given sensor. Cons: - The format is well suited for tape media but does not lend itself well for disk media. The drawbacks to this are access times for reading the data (obviously disk is faster than tape) and the simple fact of the need for some tape-to-disk translation software. - The format is highly complex at the record level and requires careful interpretation of the format documents. - There are many variations of the format documents. Each sensor (visible, thermal, SAR...) on each platform (satellite, aircraft) requires a specific version of the standard. There are currently more than ten separate documents. (I may plan to standardize these in an electronic form and make them available for FTP or somesuch. They currently reside either on paper or on various computing platforms in incompatible forms.) - The specification of a CEOS document for a new sensor and/or product may have errors through propagation, carelessness or unfamiliarity with the standard. These errors become apparent when a research scientist attempts to read a new product with previously reliable software. - There was no consideration given to the design of software tools for accessing the CEOS format. It is up to the research scientist to create `one-of' programs for reading the data. - The format is not self-describing and the research scientist must have a copy of the format document in order to comprehend the contents of a CEOS product. - The format is not suitable for archiving large amounts of data. Summary: The CEOS format has been with us for years and will continue to be a standard to maintain. However, it must be upgraded or incorporated into a complete formatting system which includes software tools and more modern methods of format specification. These include the use of data dictionaries, metadata for self-description, and the production of object classes for object oriented software to list a few. Consideration must be given not only to the end user (research scientists) but also to those who maintain archives, offer browse products and maintain catalogs. Possible Solutions: It is important to build on the work done with the CEOS format. Many of the requirements for an imagery data product have been addressed by the format. Therefore, when designing a new formatting system the following may be taken into consideration. - Remove the binary based record type codes and replace then with an explanatory ASCII text message coupled with a sensible tagging scheme much like that used in the HDF format. - Tabulate all common record fields of the CEOS format and create standard text descriptions coupled with a tagging scheme. This could also be used to create software data structures with elements using the same name/tag scheme. The majority of these fields will contain ancillary data of some form. Included in the metadata for these fields should be units and data type information. This is where a data dictionary is needed. - Remove the tape media dependent records from the CEOS format while adopting a similar record/data structure as that used for the ancillary, auxillary and other supplemental data. * -- Mark Giovannetti Canada Centre for Remote Sensing giovanne@ccrs.emr.ca Ottawa, Canada