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0.69 still can't create lossless webP
Posted: Sun Oct 12, 2014 8:18 am
by fireattack
It's related to an old bug:
http://newsgroup.xnview.com/viewtopic.php?f=79&t=29875
I'm not very sure the meaning of that bug (and its fix). was it about merely "can't set to 100%" or "can't save as lossless" or both? (Because in JPEG 100%!=lossless, not sure if it's the case in WebP)
Anyway, in 0.69, I can save as images as WebP 100%, but they're still not lossless. (the difference is small but can be observed with some photoshop).
Re: 0.69 still can't create lossless webP
Posted: Mon Oct 13, 2014 8:35 am
by xnview
when quality=100, i use lossless. Which app do you use to create lossless webp?
Re: 0.69 still can't create lossless webP
Posted: Mon Oct 13, 2014 1:30 pm
by fireattack
xnview wrote:when quality=100, i use lossless. Which app do you use to create lossless webp?
uh.. xnview MP 0.69?
Re: 0.69 still can't create lossless webP
Posted: Mon Oct 13, 2014 1:47 pm
by xnview
fireattack wrote:xnview wrote:when quality=100, i use lossless. Which app do you use to create lossless webp?
uh.. xnview MP 0.69?
ok
do you have tried official tools cwebp?
Re: 0.69 still can't create lossless webP
Posted: Mon Oct 20, 2014 1:33 am
by fireattack
xnview wrote:fireattack wrote:xnview wrote:when quality=100, i use lossless. Which app do you use to create lossless webp?
uh.. xnview MP 0.69?
ok
do you have tried official tools cwebp?
I didn't get your point, but I just read the parameters of cwebp. It separates lossy and lossless- with lossy, even you set the quality (-q) to 100 it's still lossy. Makes sense, but then what do you mean by "when quality=100, i use lossless"?
The problem still exists: XnView MP cannot create/produce lossless webP. I can use the official tool to do so for sure, but I think it's not the focus since we're talking about the bug of XnView itsefl.
By the way, this should be a bug report thread, I posted it here mistakenly. Could you help move it? Thanks.
Re: 0.69 still can't create lossless webP
Posted: Mon Oct 20, 2014 9:32 am
by xnview
fireattack wrote:
I didn't get your point, but I just read the parameters of cwebp. It separates lossy and lossless- with lossy, even you set the quality (-q) to 100 it's still lossy. Makes sense, but then what do you mean by "when quality=100, i use lossless"?
cwebp has a lossless parameter??
Re: 0.69 still can't create lossless webP
Posted: Tue Oct 21, 2014 3:52 am
by fireattack
xnview wrote:fireattack wrote:
I didn't get your point, but I just read the parameters of cwebp. It separates lossy and lossless- with lossy, even you set the quality (-q) to 100 it's still lossy. Makes sense, but then what do you mean by "when quality=100, i use lossless"?
cwebp has a lossless parameter??
If I read correctly, yes:
Code: Select all
-q float
Specify the compression factor for RGB channels between 0 and 100. The default is 75.
In case of lossy compression (default), a small factor produces a smaller file with lower quality. Best quality is achieved by using a value of 100.
In case of lossless compression (specified by the -lossless option), a small factor enables faster compression speed, but produces a larger file. Maximum compression is achieved by using a value of 100.
and
Code: Select all
-lossless
Encode the image without any loss.
Just tried, it works as it says.
Re: 0.69 still can't create lossless webP
Posted: Tue Oct 21, 2014 3:11 pm
by xnview
I've tried and it works. the webp.dll has which file date?
Re: 0.69 still can't create lossless webP
Posted: Thu Oct 23, 2014 12:22 am
by fireattack
xnview wrote:I've tried and it works. the webp.dll has which file date?
2013/03/31 (in both XnViewMP-win-x64.zip and XnViewMP-win.zip downloaded from
http://newsgroup.xnview.com/viewtopic.php?f=82&t=30761 )
And even if it could produce lossless image by setting q to 100.. it loses the ability to create q100 LOSSY webP images.
So, either way it will be less functional than the original lib. The ultimate solution should be adding a check box or option for "lossless". Then we can use it to produce both q0-100 lossy and any q0-100 of lossless image (in this case, q=compression ratio).
Re: 0.69 still can't create lossless webP
Posted: Fri Oct 24, 2014 2:40 pm
by xnview
See
Issue 518 for current status and details.
Re: 0.69 still can't create lossless webP
Posted: Fri Mar 03, 2017 9:28 pm
by helmut
This problem is supposed to be fixed in XnView MP 0.70 or later. Could you please try and confirm the bug fix, fireattack?
(Sorry for getting back to you that late!)