WEBP Export questions

[DarkClown]

All AP V2

Exporting WEBP: Just a stupid question - why can I select "lossless" and still can choose a quality "level" in percent. From my understanding you can either have the results "lossless" OR select a lower quality.

Edit: Since many other questions popped up wrt WEPP / Export I just decided to put them all in one topic

When exporting WEBP from pixel persona I can't choose "embedd ICC profile" (if this is not implemented - why do you offer it in the first place?). It works in the export persona.

If I want to choose a selected ICC profile I only get offered "Use document format" ... what if I want to select a dedicated other profile for export? And if that's not possible (or only by changing the document format) why offer it in the first place? I guess I don't understand when you want to offer more than the usual document format.

And since in terms of workflow all user input was continuosly ignored consequently export settings are NOT saved as default or stored as preset so users are forced to edit all settings for each exported picture again ... again .... again ... (I can see the programmers and marketeers laughing their butt of for still keeping the users busy with completely idiotic tasks). I tried to work with export persona hoping "default" settings would be remembered ... but I guess I'm getting to old to understand the concept (in case there is one). At least I wasn't able to somehow use the same export setting I had before again.

Frankly spoken it's no rocket science to save file- and advanced settings in customised presets (and not only thoses offered by default) and having one of these personal preset set as "default" for a certain time one works on a project.

Cheers, Timo

[R C-R]

Good questions that I have no answers for, so I am hoping someone else does & will share that with us....

[DarkClown]

10 hours ago, R C-R said:

Good questions that I have no answers for, so I am hoping someone else does & will share that with us....

I guess both of us hope so

[carl123]

14 hours ago, DarkClown said:

Just a stupid question - why can I select "lossless" and still can choose a quality "level" in percent. From my understanding you can either have the results "lossless" OR select a lower quality.

It's a complicated file format that entails spending a bit of time on the web to fully understand it but in brief...

"Lossy and lossless compression. WebP can be used for either lossy or lossless compression. These terms identify what happens when image compression is reversed. Lossy compression loses data when the file is decompressed, while lossless loses very little to no data. The advantage of lossy compression is it creates a much smaller file size than lossless can."

 

14 hours ago, DarkClown said:

And since in terms of workflow all user input was continuosly ignored consequently export settings are NOT saved as default or stored as preset so users are forced to edit all settings for each exported picture again ... again .... again ...

Presets for WebP can be created and saved and will remain the default export choice until you restart the app. Is there something specific that was not saving in a preset for you?

[DarkClown]

1 minute ago, carl123 said:

Presets for WebP can be created and saved and will remain the default export choice until you restart the app. Is there something specific that was not saving in a preset for you?

Thx, Carl - you mind explaining how that can be achieved? (aside that - as you said - this is a "temporary" feature - really?) All settings I tried to somehow "save" were lost when the nexxt pic came up ...

[carl123]

[DarkClown]

7 minutes ago, carl123 said:

It's a complicated file format that entails spending a bit of time on the web to fully understand it but in brief...

"Lossy and lossless compression. WebP can be used for either lossy or lossless compression. These terms identify what happens when image compression is reversed. Lossy compression loses data when the file is decompressed, while lossless loses very little to no data. The advantage of lossy compression is it creates a much smaller file size than lossless can."

I do understend that certain things are not as easy in life as the seem at first glimps .... but I'd appreciate (just in case people don't get the complexity instantly) some kind of "support" to understand the available option ... for me it's still: you have a lossless (compression - or not) or you have some kind of "lossy" compression ... how will that work together? Having a lossless format with 30% quality ... seems like an oxymoron to me ...

[DarkClown]

Thx for the preset hint - but it does not save file size and other settings ... 😞
Seriously - that's completely useless ...(certainly - and I did not test it - if it's gone after restart)

[carl123]

4 minutes ago, DarkClown said:

but it does not save file size and other settings

Neither do non WebP exports (this is not a specific problem for WebP)

 

5 minutes ago, DarkClown said:

but it does not save file size and other settings

Be specific (how do we know if there is a problem if you don't give details)

 

6 minutes ago, DarkClown said:

Seriously - that's completely useless ...(certainly - and I did not test it - if it's gone after restart)

The preset is still there after a restart, you just need to reselect it for that session

 

7 minutes ago, DarkClown said:

Seriously - that's completely useless ...(certainly - and I did not test it - if it's gone after restart)

Test first, ask questions later!!!!!!!!!!!!!

[carl123]

26 minutes ago, DarkClown said:

I do understend that certain things are not as easy in life as the seem at first glimps .... but I'd appreciate (just in case people don't get the complexity instantly) some kind of "support" to understand the available option ... for me it's still: you have a lossless (compression - or not) or you have some kind of "lossy" compression ... how will that work together? Having a lossless format with 30% quality ... seems like an oxymoron to me ...

Look at the slider for 0 and 100% quality when lossless is selected

0% is called WEBP (Lossless fastest)

100% is called WEBP (Lossless, smallest)

So, the "Quality" slider for Lossless is varying the file export from fastest to smallest

Although in the Affinity world smallest produces a file size bigger than when using fastest. And none of the default preset dropdown options for Lossless actually activate the Lossless checkbox.

Understandably confusing at times!

 

 

[R C-R]

21 minutes ago, carl123 said:

Understandably confusing at times!

More than confusing, it really does not seem to make much sense.

[Pšenda]

6 hours ago, DarkClown said:

Having a lossless format with 30% quality ... seems like an oxymoron to me ...

In this case, "quality" apparently does not refer to the quality of the resulting image (it should be identical to the original), but to the quality of the compression - that is, the size of the compressed file vs the complexity and thus the speed of the calculation.

[Pšenda]

6 hours ago, carl123 said:

Although in the Affinity world smallest produces a file size bigger than when using fastest.

For me work fine.
  

 

6 hours ago, carl123 said:

And none of the default preset dropdown options for Lossless actually activate the Lossless checkbox.

This must be some problem in the dialog, because the Lossless function itself is activated - after checking the box, the file size and even the preset do not change.
But after unchecking the checkbox, the size will increase, and the name of the preset will change.

 

Edited December 18, 2022 by Pšenda
Addition of Bug reporting information

[DarkClown]

7 hours ago, carl123 said:

Neither do non WebP exports (this is not a specific problem for WebP)

True! And thats an even bigger problem that has been ignored for 6 years now by serif! File size as part of a preset is essential for an efficient workflow.

[v_kyr]

The WebP file format either way (lossy or lossless) uses compression technics, thus the compression degree can be adjusted.

• Compression (lossy): WebP's lossy compression is based on VP8's keyframe-encoding.
• Compression (lossless): Lossless compression with WebP is based on various techniques that transform the parameters and image data. This includes the LZ77 algorithm.

An easier read in german about the WebP capabilities, its construction etc. would be ...

• WebP: Das effiziente Format für Bilder im Web (DE)

... in order to read the linked article in english, just throw the german article URL through the Google translate website translator and perform an german to english website translation!

[DarkClown]

7 hours ago, carl123 said:

7 hours ago, DarkClown said:

Seriously - that's completely useless ...(certainly - and I did not test it - if it's gone after restart)

Test first, ask questions later!!!!!!!!!!!!!

LOL ... I was "quoting" and trusting your comment! If your statements are not trustworthy I will have to test features myself again in future

7 hours ago, carl123 said:

Presets for WebP can be created and saved and will remain the default export choice until you restart the app.

 

[carl123]

41 minutes ago, Pšenda said:

For me work fine.
  

 

I was checking with much larger files as I wanted to test various compression settings

See what you get with the .afphoto file I have attached.

Here are my results...

 

 

 

trees.afphoto

[carl123]

4 minutes ago, DarkClown said:

LOL ... I was "quoting" and trusting your comment! If your statements are not trustworthy I will have to test features myself again in future

 

You may need to reread what I said. My statement was accurate and tested

[Pšenda]

The size difference is minimal in the given case, but it's a fairly common thing that algorithms that should lead to smaller/faster progress can in certain cases do the opposite.

[DarkClown]

6 hours ago, carl123 said:

So, the "Quality" slider for Lossless is varying the file export from fastest to smallest

Thanks for that explanation!

Did I get it right, that the "Quality" Slider changes the meaning depending on the "lossless" setting"? So it's either selecting between "size" and "Speed" (when lossless is active) - or really meaning "Quality as in JPG compression quality when lossless is NOT selected

[carl123]

 

1 minute ago, DarkClown said:

Thanks for that explanation!

Did I get it right, that the "Quality" Slider changes the meaning depending on the "lossless" setting"? So it's either selecting between "size" and "Speed" (when lossless is active) - or really meaning "Quality as in JPG compression quality when lossless is NOT selected

 

I believe so

Lossless is truly lossless as far as image quality is concerned

Just a very confusing dialog

 

[DarkClown]

Since I did some more testing I realised that the quality slider moves synchronous in the "file section" and "advanced" section (seems to be an identical setting) - while the "Lossless" checkbox can be activated in the file setting and deactivated in the advanced settings. Honestly - I'm struggeling.

Setting that are NOT saved are "File size/dimensions" and the "Area". (The ICC profile setting do not seem to work at all so it's hard to say if they are saved or not)

[DarkClown]

4 minutes ago, carl123 said:

Just a very confusing dialog

It's always difficult to use the same slider with identical name for different operations. At least the naming should change so people are aware it's a different parameter.

[Pšenda]

Whether it's WebP or JPEG, lossy or lossless compression, it's always about compression quality. Which is of course directly related to image quality, and at the same time related to compressed file size and compression/decompression speed.

[DarkClown]

7 minutes ago, Pšenda said:

lossy or lossless compression, it's always about compression quality. Which is of course directly related to image quality

How can lossless compression be about "image quality"?? I can undestand that it may be about compression speed and file size - but not "image quality". If that's the case "lossless" is the completely wrong term!