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eL_PuSHeR
Posts: 267
Joined: Sat Apr 25, 2009 9:23 am

Can the pngout addon be updated to current version?

Ken Silverman's PNGOUT

Xnview version is from 2011. Current PNGOUT version is from 2013 (February)
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DOS386
Posts: 291
Joined: Sun Jun 11, 2006 2:43 pm

> Can the pngout addon be updated to current version?

Bundling PNGOUT with XN is legally problematic. Solution (but needs work): include PNGZopfli code into LIB + NC + XN
There is indeed no WinZIP under my rock.

Noel80
Posts: 7
Joined: Tue Nov 19, 2013 10:35 am

I asked for it some time ago by email me too.
Now I simply replace pngout file in xnview folder with the last version.
By the way, there is no appreciable compression difference between old and new pngout

eL_PuSHeR
Posts: 267
Joined: Sat Apr 25, 2009 9:23 am

No. I don't think there is any noticeable compression benefits either. Ken Silverman just added a few parameters and changed some minor things here and there.
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omniplex
Posts: 127
Joined: Thu Feb 10, 2011 1:52 pm
Location: Hamburg
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DOS386 wrote:Bundling PNGOUT with XN is legally problematic.
FWIW, the newer (2013-02) pngout.exe can be started on a Windows 2000 cmd.exe command line. In other words, it should be fine for a classic XnView 2.13 32bits installation for older Windows platforms. Just keep PNGout.xnp and PNGout.lng in the XnView/AddOn folder, and replace the older pngout.exe in this folder by a newer download. The license page confirms that bundling other programs with pngout.exe would require an agreement, IANAL.

I hate obscure stuff on my box, where I have no clue what it really does. But the pngout story is mostly clear: This tool tries (hard) to find a better lossless ZIP-compression than other implementations of the ZIP-deflate algorithm. Any tool supporting PNG at all can still un-compress these smaller PNGs. If I understood it correctly pngout.exe additionally switches to the smallest possible palette if the picture uses at most 256 colours. XnView already allows to use a palette for at most 256 colours (= 8 bits), but I think XnView doesn't try to use less than 8 bits; ignoring black and white cases with one bit.

DOS386
Posts: 291
Joined: Sun Jun 11, 2006 2:43 pm

> If I understood it correctly pngout.exe additionally switches to the smallest
> possible palette if the picture uses at most 256 colours

many PNG optimizers do this ... PNGOUT additionally rersorts/messes-up the palette (???) and optimizes the Deflate compression, but it doesn't brute-force through the filters, it uses f0 for palette and f5 for true color, same as LIBPNG does.

PS: http://x128.ho.ua/pngutils.html
There is indeed no WinZIP under my rock.

omniplex
Posts: 127
Joined: Thu Feb 10, 2011 1:52 pm
Location: Hamburg
Contact:

ACK, I missed your comment here, but I saw the DOS386 there.

For blarg.xpm.png I used PNGOUT + TRUEPNG. I found the latter in a fascinating PNG tool comparison.

omniplex
Posts: 127
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Location: Hamburg
Contact:

Meanwhile (2016) TruePNG is at version 0.6.2.0, and the author of the tutorial linked on the x128 page found another tool ect for his ScripPNG (ordinary cmd-script based on TruePNG and ect among others, binaries contained in the download.)

ECT (Efficient-Compression-Tool) is on github, and unwilling to start a compiler I cheated: The ScriptPNG ZIP contains a working "ECT for PNG" thingy, I copied it to where I have TruePNG as command line tool, and ignored the rest of the ZIP.

DOS386
Posts: 291
Joined: Sun Jun 11, 2006 2:43 pm

### Re: Addons -> PNGOUT (+ TruePNG)

> Meanwhile (2016) TruePNG is at version 0.6.2.0

Version 0.6.2.2 - 2016-Apr-03
http://css-ig.net/articles/truepng wrote:Updated 1 April 2015, by Cédric Louvrier.
This text looks very interesting ... just the date is a bit silly. I downloaded all the binaries (and source where discoverable) and will test them occasionally.
There is indeed no WinZIP under my rock.

DOS386
Posts: 291
Joined: Sun Jun 11, 2006 2:43 pm

### PNG optimization

Some test results:

- binary of "Efficient-Compression-Tool" from "fast-image-optimizer.zip" does something (works on XP and DOS) ... but is absurdly bloated (1.2 MiO) and compression effect is weak even with "-s2"

Code: Select all

C:\>ect
ECT tweaked (PNG support only)
(C) 2014-2015 Felix Hanau.
Tweaks from http://css-ig.net/
Version 06.04.2016

Usage: ect [options] file.png

Options:
-s1 : fast (default)
-s2 : intense

"tweaked" seems to mean "crippled off the higher levels" ...

- "TruePNG" works (on XP and even DOS) ... the various reductions (to > 256 colours, ...) are interesting, no exhaustive tests ... why isn't TFM included in the ZIP file ?
There is indeed no WinZIP under my rock.

omniplex
Posts: 127
Joined: Thu Feb 10, 2011 1:52 pm
Location: Hamburg
Contact:

### Re: PNG optimization

DOS386 wrote:compression effect is weak even with "-s2"
Apparently a moving target, you found a version 06.04.2016, I had a version 0.2.1 linked on 2016-03-20. The news for the 2016/04/19 : Update claim that ECT was buggy before 2016-04-06, IOW, I've deleted my old copy with extreme prejudice.

Likewise I don't trust anymore that truepng.exe or any other wannabe-PNG-optimizer is good unless there is clear evidence in the form of an FFMpeg MD5 for the raw bitmap comfirming lossless. The scriptpng/lib as of today contains a truepng.exe 0.6.2.3 2016-04-08. The official version is apparently still 0.6.2.2 2016-04-03.

There's a decisive lack of README or any other kind of documentation in TruePNG_0622.ZIP, scriptpng.zip, or fast-image-optimizer.zip. And on a completely unrelated topic; the only reason why I did not nominate the enwiki FLIF page for deletion is because this is just not done without WikiMedia login.
why isn't TFM included in the ZIP file ?
You lost me here, and Google wasn't my friend since they closed iGoogle.

Ob on topic, the FLIF plugin is not contained in the XnView 2.36 full ZIP, it's a separate download. It's not listed as an installed plugin, but shows up in "supported formats" directly after FIT. There's also a new Nconvert (32bit contained in the full ZIP as always, 64bit as separate download), and a new (for me) 48x48 skin.

SharkD
Posts: 37
Joined: Sun Jul 30, 2006 6:57 am

I am having trouble understanding this thread because some of the posts are very old, and because some users' English is not very good.

Should I still be using PNGOUT today in 2016? Is there something else that works better?

In the XnView Filters menu it says the PNGOUT version is 1.00. Is this correct? Is there a newer, better version?

The reason I ask is because the version I have is stripping the alpha channel from the attached image, which is something that should never happen.

Thanks.
Attachments

XnTriq
Moderator & Librarian
Posts: 5496
Joined: Sun Sep 25, 2005 3:00 am
Location: Ref Desk

Hi SharkD.
SharkD wrote:In the XnView Filters menu it says the PNGOUT version is 1.00. Is this correct? Is there a newer, better version?
This version number refers to the file XnView/AddOn/PNGout.xnp which acts as an “intermediary” between xnview.exe and pngout.exe. The version of pngout.exe distributed with XnView v2.39 dates back to 02/Jul/2011. I believe you can replace XnView/AddOn/pngout.exe with the latest version (13/Feb/2015).

Another way of optimizing PNGs from within XnView is the RIOT add-on:
SharkD wrote:Should I still be using PNGOUT today in 2016? Is there something else that works better?
I'm using mainly pngcrush

Code: Select all

X:\pngcrush\pngcrush.exe -d X:\pngcrush\out\ -oldtimestamp -rem alla -reduce -brute X:\pngcrush\in\*.png
… and the GUI edition of PngOptimizer, but AFAIC there's nothing wrong with PNGOUT.
SharkD wrote:The reason I ask is because the version I have is stripping the alpha channel from the attached image, which is something that should never happen.
PNGOUT might have converted background_rain_shaped_c_test.png from truecolor with alpha channel to grayscale with alpha channel which is not supported by XnView.
• Original
• 97'990 bytes (truecolor + alpha channel)
• Optimized
• PngOptimizer v2.5
85'770 bytes (truecolor + alpha channel, pHYs chunk removed, IDAT chunks consolidated)
• pngcrush v1.8.10
53'683 bytes (grayscale + alpha channel, pHYs chunk removed, IDAT chunks consolidated)
• XnView + PNGOUT
51'969 bytes (grayscale + alpha channel, pHYs chunk removed, IDAT chunks consolidated)
• TinyPNG
31'647 bytes (paletted + “cheap alpha”, pHYs chunk removed, IDAT chunks consolidated)

SharkD
Posts: 37
Joined: Sun Jul 30, 2006 6:57 am

Thanks for your awesome answer! Do you know which browsers support grayscale+alpha channel? Because even if XnView does not support it, it still might be a good idea to use it on my website.

XnTriq
Moderator & Librarian
Posts: 5496
Joined: Sun Sep 25, 2005 3:00 am
Location: Ref Desk