Message-Id: <199709260707.AAA41976@dns.ccit.arizona.edu> Date: Fri, 26 Sep 1997 09:02:08 +0200 From: Emil Levine <mailto:E.Levine@IAEA.ORG> Subject: TIFF Formats To: mailto:IMAGELIB@LISTSERV.ARIZONA.EDU
Louis,Thanks for nice explanation. He is a source I found for TIFF formats: http://www.visionshape.com/tools.html and see below. I will be send you an additional email after I study your reponse.
Regards,
Emil Levine Head, UN/IAEA/INIS Clearinghouse Vienna Austria
>From: Terry Kuny[SMTP:mailto:Terry.Kuny@xist.com]
>>Sent: Monday, 22 September 1997 21:28
>>To: LEVINE, Emil
>>Subject: TIFF Formats
>>
>>Hi,
>>
>>There is a wonderful text, now with a second edition,
>>called Encyclopedia of Graphics File Formats, by Murray and
>>VanRyper (O'Reilly and Associates, Inc.) which provides a
>>nice explanation of graphics standards.
>>
>>TIFF is now up to version 6.0
>>
>>TIFF 4.0 was released in April 1987 and added support for
>>uncompressed RGB color images.
>>
>>TIFF 5.0 was released in August 1988 and was the first version
>>to add the capability of storing palette color images and
>>support for the LZW compression algorithm.
>>
>>TIFF 6.0 was released in June 1992 and added support for
>>CMYK and YCbCr color images and the JPEG compression method.
>>
>>The TIFF 6.0 specification is at:
>>
>>http://www.adobe.com/supportservice/devrelations/PDFS/TN/TIFF6.pdf
>>
>>Note: this is a PDF file.
>>
>>Compression used between the versions is dependent upon the
>>application used to create the TIFF images. Not all TIFF
>>readers will support the encoding algorithm used to
>>compress the image data. This will be true for both TIFF 4.0, 5.0
>>and 6.0 versions. For example, if a TIFF reader does not support CCITT T.4
>>and T.6 compression methods, and you have a TIFF file that
>>uses those compression methods, then you will not be able to
>>view the file with that application.
>>
>>Some TIFF readers support the reading of color TIFF files,
>>stored either as raw uncompressed data or as RLE-compressed
>>data, but don't support the decompression of LZW-encoded data.
>>
>>So the application environment for reading TIFF files is
>>the big problem since there is significant variations among
>>applications regarding which compression algorithms they
>>will understand. But this is not a problem in TIFF, as
>>the standard does not specify a particular compression
>>format to be used, but supports a variety of compression
>>formats.
>>
>>As to applications, I had a problem with Photoshop not
>>understanding CCITT T.4 compression but I have been
>>told this is now supported in the latest version of
>>Photoshop.
>>
>>A great source of information about viewers and graphics
>>applications is the Graphics File Formats FAQ
>>
>>See:
>>
>>http://www.cis.ohio-state.edu/hypertext/faq/usenet-faqs/bygroup/comp/graphic
>>s/misc/top.html
>>
>>You might also want to take a peek at:
>>
>>The Unofficial TIFF page
>>http://home.earthlink.net/~ritter/tiff/#extensions
>>
>>-terry
>>
>>
>>>From: Emil Levine <mailto:E.Levine@IAEA.ORG>
>>>Subject: TIFF Formats
>>>MIME-Version: 1.0
>>>Content-Type: text/plain; charset="us-ascii"
>>>Content-Transfer-Encoding: 7bit
>>>
>>>Dear Colleagues,
>>>
>>>I am looking for a reference that will explain the difference in TIFF
>>>files, especially TIFF 4 and TIFF 5, compressed and uncompressed. Also,
>>>software that can convert TIFF 5 and TIFF 5 compressed to TIFF 4 and
>>>TIFF 4 compressed.
>>>
>>>Thanks
>>>
>>>Emil Levine
>>>Head, INIS Clearinghouse
>>>UN/IAEA Vienna Austria
>>>Date: Fri, 19 Sep 1997 08:57:57 -0700
>>>From: Paula Berinstein <mailto:pberinstein@WORLDNET.ATT.NET>
>>>Subject: Re: TIFF Formats
>>>MIME-Version: 1.0
>>>Content-Type: text/plain; charset=ISO-8859-1
>>>Content-Transfer-Encoding: 7bit
>>>
>>>> I am looking for a reference that will explain the difference in TIFF
>>>> files, especially TIFF 4 and TIFF 5, compressed and uncompressed. Also,
>>>> software that can convert TIFF 5 and TIFF 5 compressed to TIFF 4 and
>>>> TIFF 4 compressed.
>>>
>>>Encyclopedia of Graphics File Formats by James D. Murray and William
>>>vanRyper (published by O'Reilly) mentions some differences and refers the
>>>reader to the Adobe Developer's Association at
>>>www.adobe.com/Support/ADA.html for further information. There is a BBS in
>>>Europe reachable through mailto:eurosupport@adobe.com; phone number is +44 131 458
>>>4666 (this is in Edinburgh, Scotland).
>>>
>>>The bibliography for the TIFF chapter in the encyclopedia also cites:
>>>
>>>ftp://ftp.sgi.com/graphics/tiff/
>>>http://www-mipl.jpl.nasa.gov/~ndr/tiff/index.html
>>>TIFF Developer's Toolkit, Revision 5.0, Aldus Corporation, Seattle,
>>>Washington (USA)
>>>HP TIFF Developer's Manual, 1988, published by Hewlett-Packard Company
>>>Murray, James. "TIFF File Format," C Gazette, Winter 1990-1, pp. 27-42.
>>>
>>>Hope this is helpful.
>>>
>>>Paula Berinstein
>>>Berinstein Research
>>>Woodland Hills, CA
>>>mailto:pberinstein@worldnet.att.net
>>>
>>
>>
>----------
>From: Louis H. Sharpe II[SMTP:mailto:lsharpe@PICTUREL.COM]
>Sent: Thursday, 25 September 1997 08:56
>To: mailto:IMAGELIB@LISTSERV.ARIZONA.EDU
>Subject: Re: TIFF Formats
>
>At 04:07 PM 9/19/97 +0200, you wrote:
>
>>I am looking for a reference that will explain the difference in TIFF
>>files, especially TIFF 4 and TIFF 5, compressed and uncompressed. Also,
>>software that can convert TIFF 5 and TIFF 5 compressed to TIFF 4 and
>>TIFF 4 compressed.
>
>Reading between the lines, I am wondering if you have a piece of software
>which claims to read TIFF 4 files, which is choking on some later vintage
>file you are submitting to it.
>
>In that narrow context or in the wider one of your question, there are a
>few things to say.
>
>1. TIFF files of a single version still come in multiple "flavors," each
>supporting different compression types, pixel depths, number of colors, etc.
>
>2. The practical difference between files having different TIFF versions
>may well be much smaller than the difference between TIFF files of the same
>version which are of different "flavors."
>
>3. The above said, the best approach is to "dump" the structure of the
>offending ("TIFF 5") files and of an instance of the files of the desired
>("TIFF 4") type. This is most easily accomplished using a public domain DOS
>utility we have compiled and placed on our web site at:
>
> http://www.picturel.com/utils.html
>
>The utility is called TIFFLOAD.EXE. After downloading to an appropriate
>machine, run the command lines:
>
> tiffload tiff5im.tif > tiff5im.txt
> tiffload tiff4im.tif > tiff4im.txt
>
>A careful look at the two text files will tell you what the differences are.
>
>4. These differences may be of several sorts:
>
> a. The TIFF 5 file may have compression types not supported in TIFF 4
>(likely). In particular, the early TIFF versions used a variant version of
>CCITT Group 3 compression (sometimes called "TIFF Group 3") for binary
>images, which has no end of line (EOL) codes. This method is no longer
>advisable to use.
> b. The TIFF 5 file may have tags not supported in TIFF 4 (guaranteed, but
>good TIFF readers are supposed to ignore tags they do not understand,
>without dying). Utilities exist to remove tags deemed offensive, although
>important semantics can be lost in this way. One utility called tiffcp is
>available on a wide variety of machines as part of the libtiff TIFF library
>package (a good TIFF dumper is also included).
>
>I seem to have mislaid my copies of the TIFF 4 and 5 specifications. If
>anyone can provide a copy of either, I would be grateful.
>
>Hope this helps!
>
>Lou
>
>Louis H. Sharpe II mailto:lsharpe@picturel.com
>Picture Elements, Inc. +1 303-444-6767
>410 22nd Street, Boulder, CO 80302 USA fax +1 303-415-1392
>http://www.picturel.com PGP Key Available: http://www.pgp.com
>