Page 1 of 2 12 LastLast
Results 1 to 10 of 11

Thread: Inkscape Save Problem

  1. #1
    Guild Adept icosahedron's Avatar
    Join Date
    Feb 2009
    Posts
    337

    Post Inkscape Save Problem

    I'm experiencing a problem with inkscape saves (v0.46) - maybe I'm doing something wrong?

    Saving as svg is fine, but there is no option to save as png, it's not listed on the save as type list. There is an option to 'guess from file extension', and I have added .png to the filename, chosen 'guess from file extension and saved.

    However, there is no thumbnail generated when I browse for the png in Explorer, and my image browser (Xnview) can't see it. When I try to open the png again in Inkscape I get a runtime error and the program crashes, but Gimp opens the png with no problems. If I then do a Save As from Gimp, the png saves normally, I can see it in my browser, and Inkscape opens it.

    Any ideas what is happening? I don't want to have to use Gimp to open and resave every png I produce with Inkscape.
    Mapping a Traveller ATU.

    See my (fantasy-based) apprenticeship blog at:

    http://www.viewing.ltd.uk/cgi-bin/vi...forums&sx=1024

    Look for Chit Chat, Sandmann's blog. Enjoy.

  2. #2
    Guild Master Gracious Donor Midgardsormr's Avatar
    Join Date
    Aug 2007
    Location
    Los Angeles, CA
    Posts
    2,442

    Post

    I don't have Inkscape installed right now, but I suspect that you need to export rather than save as. PNG is a raster format, not a vector one, so Inkscape can't edit it once it's been made. Saving is for files that you can open and work on again. Exporting is for converting to another format which cannot be manipulated by the software.
    Last edited by Midgardsormr; 04-19-2009 at 11:48 AM.
    Bryan Ray, visual effects artist
    http://www.bryanray.name

  3. #3
      Naeddyr is offline
    Guild Adept Naeddyr's Avatar
    Join Date
    Jun 2008
    Location
    Finland
    Posts
    289

    Default

    Inkscape is not a raster program, so it won't save it as PNG or open your png files for editing! To save as a png, you will have to export it, using either menu > export or the export toolbar icon. To open a png in inkscape (or any raster image), you have to import it into inkscape as an object.

    I suspect that when you save it as ".png", you are saving it as a svg with a false .tag! When Inkscape tries to open this, it crashes; explorer doesn't make thumbnails out of SVG files; and GIMP actually converts your SVG file into a raster file for editing.

    Btw, exporting from Inkscape saves it as a 24-bit PNG, so if you want it indexed, you need to open it in GIMP anyhow.

  4. #4
    Guild Adept icosahedron's Avatar
    Join Date
    Feb 2009
    Posts
    337

    Default

    Thanks guys. You're right, I should have exported.
    Naeddyr, you were spookily right. Inkscape was saving as svg with a false tag and Gimp was converting it, so I never had a png until Gimp created one. I didn't notice what it was doing until you highlighted it.

    What is 'indexed'?
    Is 24-bit bad?
    Mapping a Traveller ATU.

    See my (fantasy-based) apprenticeship blog at:

    http://www.viewing.ltd.uk/cgi-bin/vi...forums&sx=1024

    Look for Chit Chat, Sandmann's blog. Enjoy.

  5. #5
      Naeddyr is offline
    Guild Adept Naeddyr's Avatar
    Join Date
    Jun 2008
    Location
    Finland
    Posts
    289

    Post

    Quote Originally Posted by icosahedron View Post
    Thanks guys. You're right, I should have exported.
    Naeddyr, you were spookily right. Inkscape was saving as svg with a false tag and Gimp was converting it, so I never had a png until Gimp created one. I didn't notice what it was doing until you highlighted it.

    Hu hu hu hu hu. :3



    What is 'indexed'?
    Is 24-bit bad?
    Colours on images are stored as sets of numbers. The simplest way is to use 0 and 1 for black and white (which one computers can be very very efficient), the next simplest is to have a small amount of unique colours, and just list what they are, and then you have when you simply leave out any inhibitions and encode everything with several bytes. 16-bit is when you have 255x255x255 (FF.FF.FF) combinations, red green and blue, and 24 is when one more channel is introduced in the form of alpha transparency.

    An indexed file is simply a file with a palette or certain set of colours encoded in it (usually 255 colours is the upper limit). GIF are always indexed, but PNG can be both 24-bit (with transparency) and indexed (without, iirc). If your image has only a small amount of unique colours, and indexing doesn't cause degradation, it usually is better to use indexed so that you get a much smaller sized file. If your image has a lot of unique colours, and it does not have large swathes of a single colour (red is an offender here), it's usually also better to use JPG than 24-bit PNG. The differences in size are usually considerable.
    Last edited by Naeddyr; 04-19-2009 at 05:52 PM.

  6. #6
    Guild Master Gracious Donor Midgardsormr's Avatar
    Join Date
    Aug 2007
    Location
    Los Angeles, CA
    Posts
    2,442

    Post

    Be aware, though, that an indexed PNG with transparency will tend to have rougher edges because it's more difficult to anti-alias (smooth away the "jaggies") with fewer colors. If you need good crisp edges for a stamp, you're usually best off sticking with a 24-bit PNG.
    Bryan Ray, visual effects artist
    http://www.bryanray.name

  7. #7
      Naeddyr is offline
    Guild Adept Naeddyr's Avatar
    Join Date
    Jun 2008
    Location
    Finland
    Posts
    289

    Post

    Quote Originally Posted by Midgardsormr View Post
    Be aware, though, that an indexed PNG with transparency will tend to have rougher edges because it's more difficult to anti-alias (smooth away the "jaggies") with fewer colors. If you need good crisp edges for a stamp, you're usually best off sticking with a 24-bit PNG.
    Just tried it out (thought PNG had only transparency support for 24-bit), and it seems like it can only support one transparent colour (so there's no alpha-channelled colours). Wonder why... I mean, adding alpha-channel support in a palette would only marginally increase file-sizes (that's what like, 255 bytes, 0.25 kbytes per file).
    Attached Images Attached Images  

  8. #8
    Guild Adept icosahedron's Avatar
    Join Date
    Feb 2009
    Posts
    337

    Default

    Phew, a lot of that is over my head, guys.
    I know that jpg takes up less space, but you can't use it for transparency, and if you keep tweaking and resaving it, errors build up with each save.
    I didn't know there were two types of PNG though. Most of my stuff is simple (simple is my limit. ) so 255 colours might be all I need. However, I'll just take whatever the software offers for now and worry about the differences when I have more knowledge.
    At least now I have some form of png saved.
    Thanks.
    Mapping a Traveller ATU.

    See my (fantasy-based) apprenticeship blog at:

    http://www.viewing.ltd.uk/cgi-bin/vi...forums&sx=1024

    Look for Chit Chat, Sandmann's blog. Enjoy.

  9. #9
    Guild Master Gracious Donor Midgardsormr's Avatar
    Join Date
    Aug 2007
    Location
    Los Angeles, CA
    Posts
    2,442

    Post

    Quote Originally Posted by Naeddyr View Post
    Just tried it out (thought PNG had only transparency support for 24-bit), and it seems like it can only support one transparent colour (so there's no alpha-channelled colours). Wonder why... I mean, adding alpha-channel support in a palette would only marginally increase file-sizes (that's what like, 255 bytes, 0.25 kbytes per file).
    But an indexed file doesn't use channels at all. PNG-8 can actually support more than one transparent color, but not translucency. It depends on your software whether or not you can designate more than one transparent color, though.

    Ico: There are actually four versions of PNG, but all that's important to know is that 8-bit PNG is smaller, but it doesn't do angled and round boundaries well. If your stamps are square, 8-bit is fine. If not, use 24-bit.
    Bryan Ray, visual effects artist
    http://www.bryanray.name

  10. #10
      Naeddyr is offline
    Guild Adept Naeddyr's Avatar
    Join Date
    Jun 2008
    Location
    Finland
    Posts
    289

    Post

    Quote Originally Posted by Midgardsormr View Post
    But an indexed file doesn't use channels at all. PNG-8 can actually support more than one transparent color, but not translucency. It depends on your software whether or not you can designate more than one transparent color, though.
    I meant in the colour definitions, where they have to use channels to define the palette. You might as well add translucency at this point.

Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •