Partial Transparence in GFL_COLORS and GFL_GREY

[lazyeugene]

Do you plan to support alpha transparency for GFL_COLORS and GFL_GREY modes in gfl library (And XnView as well)?

For Example look at this attached file (save and use xnview or gfl-based app to view it):

RedbrushAlpha-0.5.png (113.15 KiB) Viewed 7379 times

Some examples may be found here:
http://entropymine.com/jason/testbed/pngtrans/

All RBGA pictures displays perfectly, but images with palette or grayscale images are viewed poorly

Thanking for your work, waiting for the answer.

[XnTriq]

It's a known limitation:

• Transparency & alpha
• 8 bit png with alpha (8 bits) mask

[lazyeugene]

Yes. I know. But my question is "Do you plan to support alpha transparency for GFL_COLORS and GFL_GREY modes in gfl library"?

[xnview]

Yes. I know. But my question is "Do you plan to support alpha transparency for GFL_COLORS and GFL_GREY modes in gfl library"?

I don't know, this feature has not a high priority

[lazyeugene]

Image viewer not showing images correctly, and showing them correctly is not a high priority. It's pretty sad.

[XnTriq]

I don't know, this feature has not a high priority

Ouch!

I certainly don't want to put you under pressure or get on your nerves, Pierre. We all know very well that you've got your hands full with GFL/GFLAx, (X)nConvert, XnView v1.96 incl. Shell Extension & Media Detector, versions for PocketPC + Smartphone, and — last but not least — the new MP project.

Of course, most people use XnView for working with photos. Although I do not have the numbers to prove my point, it's my firm belief that a significant portion of the user base sees it as imaging central (or a Rosetta Stone for file formats, if you will).

Full support for all flavors of the most common image formats (BMP, GIF, JPEG, and PNG) should not be relegated to a low-level priority. It sucks that I have to rely on the competition when I'm dealing with greyscale or palette-based/indexed PNGs plus alpha channel, which are no longer a rare occurrence “in the wild”.

• Wikipedia: Portable Network Graphics » Transparency of image
• Kevin Freitas: One PNG, two browsers, no hacks » Sample (12/Aug/2004)
• Adobe TechNote: Fireworks transparency issues » Alpha transparency and the PNG file format (19/Nov/2004)
• Punchkick Interactive: Learn how to cut the size of transparent images for the Web by more than 70% using Fireworks (09/Apr/2007)
• Trevor Morris Photographics: The PNG File Format » Photoshop and PNG (13/Jun/2007)
• SitePoint Blogs: PNG8 – The Clear Winner » Demo page (18/Sep/2007)
• David Stong: PNG8 alpha transparency from Fireworks » Test page (20/Sep/2007)
• Make Magazine Blog: HOWTO: cross-browser alpha PNGs (08/Feb/2008)
• Cozi Tech Blog: Transparent PNGs Can Deadlock IE6 (10/Mar/2008)
• Community MX: Creating 8-bit Alpha Transparent PNG Files (13/Mar/2008)
• SitePoint Blogs: Making ‘IE6-friendly’ PNG8 Images » Live example (20/Mar/2008)
• ArtzStudio: PNG Alpha Transparency – No Clear Winner (25/Jul/2008)
• BytesizeCSS: Alpha PNG8 in Fireworks (10/Aug/2008)
• CSSing: Альфа-каналы в PNG-8 » PNG-8 альфаканалы (07/Nov/2008)
• Jay Salvat: PNG 8 Bits avec transparence Alpha, c'est possible! (13/Nov/2008)
• John Dyer: PNG transparency in IE6 (without JavaScript) (02/Dec/2008)
• Brenelz's Web Development Tips: PNG-8 Alpha Transparency (screencast) (27/Jan/2009)
• Ethan Gardner Web Design: Alpha Transparency in PNG-8 Images Without Using Fireworks (13/Feb/2009)
• Pew Pew Laser Blog: Removing the Grey Background on .PNGs in IE6 Using Fireworks (18/Feb/2009)
• commadot.com: PNG-8 that acts like PNG-24 without Fireworks (24/Feb/2009)
• Make Magazine Blog: pngquant and pngnq – alpha PNG-8 images from the command-line (23/Mar/2009)
• ThemeForest Community Blog: Image Types and Usage in Web Design (01/Apr/2009)
• Jesse Schoberg: Degradable PNG Transparency for IE6 (03/Jul/2009)
• Smashing Magazine: Clever PNG Optimization Techniques (15/Jul/2009)
• Alan Ayoub: Taming your PNGs (04/Sep/2009)
• Usability Distilled: Getting good edge transparency with an bit png image (15/Sep/2009)
• porneL: Improved pngnq
• V-Methods: JPEG Imager » PNG Palette Semi-transparency Demo
• Gregg Hilferding: ImageMagick Convert PNG32 to Alpha PNG8

[MaxSt]

Fully agree with above posters. Core functionality should not be a low priority.

We all read stories how in the past Internet Explorer couldn't handle PNG files correctly.

Well, now we have IE8 that handles PNG better than XnView.

Isn't it sad?

[xnview]

Yes, my internal library doesn't support 8bits+alpha picture, so it's not very easy to change it.
But i'll try

[MaxSt]

I thought you use libpng...

It's very simple to use [256][4] array for palette.

a) save PLTE into [col][0] and [col][1] and [col][2]
b) save tRNS into [col][3].

[xnview]

I thought you use libpng...

The problem is not libpng, but my core library

[lazyeugene]

I want to say: Thank you, Pierre! Thank you not for doing this, but for saying "i'll try" and for your work.

[lazyeugene]

Today i received one psd file. There is a problem: if alpha channel is disabled, gfl (and xnview as well) still reads it. Could you fix gfl (and xnview) to not read disable channels? Thanks a lot!

[xnview]

Today i received one psd file. There is a problem: if alpha channel is disabled, gfl (and xnview as well) still reads it. Could you fix gfl (and xnview) to not read disable channels? Thanks a lot!

Could you send me a sample

[lazyeugene]

Here is the one: http://x.uch.net/dl.php?dl_id=35499&dl_ ... 3201912b9a

It's too big to attach here (approx 1.4M), so I put it on file exchange hosting. It will keep the file for three days. Please, tell me if you can't download it, so I'll try another service to keep this file for you.

[XnTriq]

How come that XnView v1.96.5 does a better job creating the thumbnail than with the preview?

• 
  Preview (left) & thumbnail (right) of 8bit-trans.png

• 
  TweakPNG