TIFF settings (LZW vs. ZIP)

Discussion in 'Photoshop Tutorials' started by Phil, Squid-in-Training, Oct 5, 2003.

  1. Hey all. I noticed when I saved in TIFF, there is an LZW and ZIP option.
    ,When I save files in LZW, they average 4 or 5MB, whereas when I save files
    in ZIP, they average 15MB. What's the difference? Are they both lossless?
    Other than the patent BS, is there any downside to using LZW comp?
     
    Phil, Squid-in-Training, Oct 5, 2003
    #1
    1. Advertisements

  2. Totally different algoritms, and probably by chance LZW is better this
    time. It wouldn't surprise me if you could also find a case where it's
    the other way round. Both are indeed lossless.
    Not really, except that some programs do not read compressed TIFF
    because of the patent issue. ZIP is worse though: TIFF files with LZW
    compression can be read by many other programs, but most programs cannot
    read TIFF files with ZIP (or JPEG) compression.
     
    Johan W. Elzenga, Oct 5, 2003
    #2
    1. Advertisements

  3. Phil, Squid-in-Training

    Eric Gill Guest

    You can do a web search for the technical details. Suffice it to say, I
    have no idea why Adobe bothered writing the code.
    LZW is the one form of compression allowed by the Tiff format that's been
    around for years - all the others were added in 6.x of Photoshop. I
    haven't the foggiest if there is much support for them in other
    applications as there is no good reason to use them, but I cannot imagine
    it's widespread.

    LZW is an excellent way to compress 1-bit lineart for transmission. Other
    than that, support in 3rd-party apps is still not universal all these
    years later, can cause odd problems in prepress, shows a small but
    noticeable performance hit whilst working in PSHOP. With hard drive space
    under 75 cents a gig, why bother?
     
    Eric Gill, Oct 5, 2003
    #3
  4. Because I'm a student on a budget with a laptop ;)

    Thanks all!
     
    Phil, Squid-in-Training, Oct 5, 2003
    #4
  5. Totally different algoritms, and probably by chance LZW is better this
    I found why my sizes were so different: I scanned in different resolutions
    when I used LZW and ZIP respectively... turns out that LZW seems to be
    slightly larger actually.
     
    Phil, Squid-in-Training, Oct 5, 2003
    #5
  6. Compressing tiff is not a good idea. LZW is certainly the only
    standard compression method for tiff. I do not know how many people
    accepted Zip. But LZW has the patten issue.

    Tony G. Smith
    Vizros - Realistic 3D page curl plug-ins and more
    Demo at http://www.vizros.com/gallery.html
     
    Vizros Plug-ins, Oct 5, 2003
    #6
  7. What's wrong with it?
     
    Johan W. Elzenga, Oct 5, 2003
    #7
  8. Phil, Squid-in-Training

    Eric Gill Guest

    Been there, pretty much. Once upon a time I was limited to a 286 with an 80
    *meg* hard drive and used on-the-fly compression on the entire hard drive
    (still an option, BTW. Microsoft stole the technology, then bought the
    company when sued). I wouldn't have done it but for neccesity, believe me.

    But LZW sounds like the best compromise for your situation. If you can
    manage it, remember to uncompress or at least tell the service boys if you
    have to send your files to be printed.
    You bet.
     
    Eric Gill, Oct 5, 2003
    #8
  9. Phil, Squid-in-Training

    Warren Sarle Guest

    I usually find that ZIP is much better than LZW for photos. Often, LZW
    actually increases the file size for 16-bit images. If Photoshop is the
    only image processing program you're using, ZIP is quite useful.
     
    Warren Sarle, Oct 6, 2003
    #9
  10. LZW is certainly the only standard compression method for tiff.

    Where does 'Deflate' compression fit into all of this? I find that using
    something like ACDSee to compress a TIFF image I generally get smaller files
    out of Deflate than LZW. And it seems that more applications have less
    objections to Deflate compression than they do with LZW compression.

    Just curious,
    Andrew.
     
    Andrew Novinc, Oct 6, 2003
    #10
  11. It has nothing to do with file size. You need to think about your
    users and viewers. You need to ask youself

    1. If needed, which one they would like to pay? LZW license or disk
    drive?
    2. How many of them can decompress "Deflate"?

    Tony G. Smith
    Vizros - Realistic 3D page curl plug-ins and more
    Demo at http://www.vizros.com/gallery.html
     
    Vizros Plug-ins, Oct 6, 2003
    #11
  12. Phil, Squid-in-Training

    Tacit Guest

    It has nothing to do with file size. You need to think about your
    Users and viewers never have to pay the LZW license fee; it must be paid only
    by people who create software that *writes* LZW-compressed files.

    Or had to pay, that should be. The patent on LZW compression expired on June
    20, 2003.
     
    Tacit, Oct 6, 2003
    #12
  13. Phil, Squid-in-Training

    Bill Hilton Guest

    From: "Phil, Squid-in-Training"
    For 8 bit files this is what I saw too, in almost all cases ZIP was somewhat
    smaller.

    For 16 bit files it's not worth the effort, the savings are small or, in some
    cases, the "compressed" file is larger than the original.

    Bill
     
    Bill Hilton, Oct 7, 2003
    #13
  14. If you have the license to *Read*, you have the license to *write*. If
    you do not have the license to *write*, you do not have the license to
    *Read*. If you buy PS, for example, you have the license to *write*
    and *read* on your computer. But if you distribute the images to
    someone else, he needs the license himself.

    Tony G. Smith
    Vizros - Realistic 3D page curl plug-ins and more
    Demo at http://www.vizros.com/gallery.html
     
    Vizros Plug-ins, Oct 8, 2003
    #14
  15. Phil, Squid-in-Training

    Tacit Guest

    If you have the license to *Read*, you have the license to *write*.

    That is incorrect. There are many viewer programs which can read images but not
    write them.

    And if you have an image viewer which can write them, you have a license. Only
    the PROGRAMMER pays the fee.

    And it's a non-issue. The LZW patent expired on June 20, 2003.
     
    Tacit, Oct 8, 2003
    #15
  16. But your image user may not be someone just want to see it. Maybe he
    wants send it to a special printer, maybe he wants store it to an
    image system, maybe he wants do image analysis, maybe he wants wirte
    program to retrieve special information, maybe he wants decompressed
    it and save to database. If he does not have a LZW license or tools,
    he has a problem.


    Tony G. Smith
    Vizros - Realistic 3D page curl plug-ins and more
    Demo at http://www.vizros.com/gallery.html
     
    Vizros Plug-ins, Oct 10, 2003
    #16
  17. How could anyone even apply for a license for an expired patent? And
    why?

    Yours confused,

    --
    Kulvinder Singh Matharu
    Contact details : http://www.metalvortex.com/form/form.htm
    Website : http://www.metalvortex.com/

    "It ain't Coca Cola, it's rice" - The Clash
     
    Kulvinder Singh Matharu, Oct 10, 2003
    #17
  18. Phil, Squid-in-Training

    Tacit Guest

    But your image user may not be someone just want to see it. Maybe he
    All that can be done and always could be done without needing an LZW license.
    That can also be done without an LZW license.
    That is incorrect.

    And you aren't paying attention. The LZW patent expired on June 20, 2003. There
    is no patent on LZW any more. No license needed.
     
    Tacit, Oct 10, 2003
    #18
  19. How about the tools needed for LZW?

    Tony G. Smith
    Vizros - Realistic 3D page curl plug-ins and more
    Demo at http://www.vizros.com/gallery.html

     
    Vizros Plug-ins, Oct 10, 2003
    #19
  20. Phil, Squid-in-Training

    Tacit Guest

    How about the tools needed for LZW?

    What about the tools needed for LZW?

    The patent on LZW compression has expired. There are public-domain source code
    and tools for LZW compression and decompression everywhere. Because the patent
    has expired, none of these tools is encumbered by patent licensing concerns.
     
    Tacit, Oct 11, 2003
    #20
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.