Photo cannot enlarge the thumbnails to view them

[thomaso]

8 minutes ago, R C-R said:

But do we know which one it provides? From what I have seen from the column view, it may be a high resolution thumbnail, the same as or equivalent to opening the file in Affinity & zooming to the pixel view size.

Users don't need to know about the code but report their visual experience. From the users perspective it is sufficient to point Serif to the issue, which obviously occurs and obviously appears to be related to native Affinity documents (not to its exports).

[R C-R]

2 minutes ago, thomaso said:

Users don't need to know about the code but report their visual experience. From the users perspective it is sufficient to point Serif to the issue, which obviously occurs and obviously appears to be related to native Affinity documents (not to its exports).

It doesn't matter what users point Serif to if everything Serif can do to provide high resolution thumbnails already has been done.

[v_kyr]

1 hour ago, thomaso said:

Even if Quick Look generates previews it is Affinity who provides all info to Quick Look, including preview size. It can be an icon, a low res thumbnail or a thumbnail preview.

https://developer.apple.com/documentation/quicklook :

https://devstreaming-cdn.apple.com/videos/wwdc/2019/719dyb631z49zpjzk/719/719_whats_new_in_file_management_and_quick_look.pdf?dl=1 :

 

Yes the framework changed in newer (the latest) MacOS versions and offers different representation types, which in turn do offer different load speeds and also do affect the quality & size of shown thumbnails. Thus it depends highly on the representation type used and returned, since not all types (icon, lowQualityThumbnail, or thumbnail) might be available for a given thumbnail. And so on, see ...

• What’s New in File Management and Quick Look (from 9:15 & >= 11:00 there)

 

[R C-R]

11 minutes ago, v_kyr said:

Thus it depends highly on the representation type used and returned, since not all types (icon, lowQualityThumbnail, or thumbnail) might be available for a given thumbnail.

So might this mean that Affinity's Quick Look generator already is capable of providing all these types & which one is returned/used depends on some adaptive consideration of load speed vs. responsiveness?

I don't know if it is relevant but I have noticed that if I manually resize a Quick Look preview window, up to a certain size there is no noticeable lag & the image size updates smoothly, but if I go larger or choose the full screen view there sometimes is a (usually a very brief) one-time lag, as if it is loading a higher resolution image that replaces the lower resolution & more pixelated one.

I do not remember this happening with my older & much lower performance 2012 iMac -- IIRC, the image just got more pixelated & was never replaced with a  higher resolution version.

Anybody seeing anything similar on their Macs?

[lepr]

6 hours ago, R C-R said:

So might this mean that Affinity's Quick Look generator already is capable of providing all these types & which one is returned/used depends on some adaptive consideration of load speed vs. responsiveness?

I don't know if it is relevant but I have noticed that if I manually resize a Quick Look preview window, up to a certain size there is no noticeable lag & the image size updates smoothly, but if I go larger or choose the full screen view there sometimes is a (usually a very brief) one-time lag, as if it is loading a higher resolution image that replaces the lower resolution & more pixelated one.

I do not remember this happening with my older & much lower performance 2012 iMac -- IIRC, the image just got more pixelated & was never replaced with a  higher resolution version.

Anybody seeing anything similar on their Macs?

Using the 1.8.4 apps on macOS 10.13.6, an Affinity document's embedded thumbnail has 512 pixels in its longer dimension, and that embedded thumbnail is displayed by Finder and Quick Look.

[thomaso]

@R C-R, meanwhile I lost your approach, don't understand with what aim you are arguing.

Back to that thread and its two reports about an issue of preview size with native Affinity files we do KNOW that ...

1. previews for native Affinity files are smaller than for its exported files, e.g. JPGs and other previews.
2. an open preview window may manually get enlarged by the user but then makes its lower resolution obvious (again compared to other files, e.g. JPGs).
3. a manually upscaled preview window jumps back to its initially smaller size when it gets opened next time.

Why this happens, especially what piece of code in Affinity prevents the appearance as expected of a preview or what part disturbs a proper communication with Quick Look, is not necessary to know to point out this unexpecetd, unwanted and irregular, divergent visual user experience.

[R C-R]

27 minutes ago, thomaso said:

@R C-R, meanwhile I lost your approach, don't understand with what aim you are arguing.

I am just asking how manually resizing the Quick Look preview window behaves on other users' Macs, specifically if there is some 'threshold' size above which the preview changes from a lower to higher resolution image, & if there is any difference in this behavior for Macs running different macOS versions and/or for different hardware configurations.

For me on this iMac (specs below in my sig), as I explained I do not always see your #2 behavior. I am trying to understand why that happens.

EDIT: Also, regarding Quick Look previews for jpgs, pngs, & other raster image formats, depending on the pixel dimensions of the file & the filetype, the default Quick Look preview size I get may be anything from what appears to be that 'native' pixel size to a re-rendered & interpolated upscaled or downscaled version of it. IOW, it may be a scaled up low resolution preview that looks like a high resolution one because it has been anti-aliased (by what I am not sure) or a larger than screen-sized high resolution one that has been scaled down & anti-aliased to fit on the screen.

[thomaso]

26 minutes ago, R C-R said:

specifically if there is some 'threshold' size above which the preview changes from a lower to higher resolution image

(...) I do not always see your #2 behavior.

To me a native Affinity file preview never switches to a higher quality (resolution) when I enlarge the window, regardless of separate Quick Look window or finder window in any viewing mode.

Here also the native Affinity preview is not related to either pixel dimensions of the .afpub vs. of preview window size, nor to its saved DPI. For instance an .afpub with 2600 px width always shows a lower preview resolution than the same content exported as JPG or PDF, and it doesn't change with 72 or 300 DPI for the .afpub.

[R C-R]

1 minute ago, thomaso said:

To me a native Affinity file preview never switches to a higher quality (resolution) when I enlarge the window, regardless of separate Quick Look window or finder window in any viewing mode.

On this iMac it sometimes does switch. Like I said, I do not recall this ever happening with the old iMac but I am not certain about that or if it is somehow related to some adaptive process based on the hardware capabilities of the Mac, the performance preference settings, or something else, or even what controls that process if it does exist.

[lepr]

1 hour ago, R C-R said:

On this iMac it sometimes does switch. Like I said, I do not recall this ever happening with the old iMac but I am not certain about that or if it is somehow related to some adaptive process based on the hardware capabilities of the Mac, the performance preference settings, or something else, or even what controls that process if it does exist.

Please show evidence of a high res Quick Look view of an Affinity document: capture a screenshot (shift+cmd+3) of Quick Look in full screen mode and attach that screenshot to a reply. You might need to zip the huge screenshot for the forum to accept it.

[R C-R]

15 hours ago, R C-R said:

I think but am far from sure that these previews are separate from & independent of the embedded thumbnails that optionally can be included in native format Affinity files via the "Save thumbnails with documents" item in Preferences > General; & thus would not contribute anything to the native format file size like embedded thumbnails do.

I should have tested this before I wrote that. If I disable "Save thumbnails with documents" & do a 'save as' for an existing Affinity Designer document, the only preview I get apparently comes from an *.icns file in the /Applications/Affinity Designer.app/Contents/Resources/ folder. It can be displayed at large sizes (up to 1024x1024 px) but it is just a 'flat' icon version of the app's icon:

I did not test this with AP or APub but I assume they work the same way.

[v_kyr]

• Mark Ingram: We store a preview image in the file, for use with OS previews (so that we can quickly display the image, without having to render the entire document).

• AP: Quicklook previews wrong size again

 

[R C-R]

3 hours ago, anon2 said:

Please show evidence of a high res Quick Look view of an Affinity document: capture a screenshot (shift+cmd+3) of Quick Look in full screen mode and attach that screenshot to a reply. You might need to zip the huge screenshot for the forum to accept it.

Well, this is unsettling. Like I said, it only happens sometimes. While I was trying to figure out the steps that made it happen, I created & saved to the desktop this very simple Untitled 1.afdesign file. Then I switched to Finder, selected that file, tapped the spacebar to bring up the Quick Look view. But even before using shift+cmd+3, I could see that something was not working right because this is what I saw:

The zipped full screen version: screenshot.jpg.zip

So far I have not been able to figure out how to coerce the Quick Look view or the desktop thumbnail of the file to show anything different. The afdesign file opens normally, showing just the rectangle & diagonal line, but the QL view & thumbnail seem to be stuck showing what you see above.

I have never seen anything like this happen before (on this new or my older iMac) so I guess I have somehow done something that broke AD, the QL generator, or something else. I am not sure how much more effort I want to put into tracking down the cause of this for now -- I need to do some work around the house today & I would like to watch a football game this evening -- but I will try to update the topic in the next day or two if I find anything that seems relevant.

[lepr]

1 hour ago, R C-R said:

Well, this is unsettling. Like I said, it only happens sometimes. While I was trying to figure out the steps that made it happen, I created & saved to the desktop this very simple Untitled 1.afdesign file. Then I switched to Finder, selected that file, tapped the spacebar to bring up the Quick Look view. But even before using shift+cmd+3, I could see that something was not working right because this is what I saw:

The zipped full screen version: screenshot.jpg.zip

So far I have not been able to figure out how to coerce the Quick Look view or the desktop thumbnail of the file to show anything different. The afdesign file opens normally, showing just the rectangle & diagonal line, but the QL view & thumbnail seem to be stuck showing what you see above.

I have never seen anything like this happen before (on this new or my older iMac) so I guess I have somehow done something that broke AD, the QL generator, or something else. I am not sure how much more effort I want to put into tracking down the cause of this for now -- I need to do some work around the house today & I would like to watch a football game this evening -- but I will try to update the topic in the next day or two if I find anything that seems relevant.

 

Your zipped 5120 pixels wide screenshot (disregarding the JPEG compression artefacts) shows a 512 pixels wide image has been scaled 10-fold. That's consistent with what is known about the Affinity document thumbnail size - it is only 512 pixels in the longer dimension - and it is that thumbnail which is displayed by Quick Look.

Here is your Affinity document saved to a new file with an uncorrupted embedded thumbnail: Untitled 2.afdesign

(JPEG screenshots are bad form, by the way.)
 

 

[R C-R]

On 9/13/2020 at 2:50 PM, anon2 said:

Your zipped 5120 pixels wide screenshot (disregarding the JPEG compression artefacts) shows a 512 pixels wide image has been scaled 10-fold. That's consistent with what is known about the Affinity document thumbnail size - it is only 512 pixels in the longer dimension - and it is that thumbnail which is displayed by Quick Look.

What concerns me is that the thumbnail itself is not a preview of my file -- it looks like two different versions of it scaled to different sizes, with one of them only partially rendered.

As for the jpeg format of the screenshot, that is because long ago I set all my screen captures to use the jpeg format (via TinkerTool) & you requested I use shift-cmd-3 to take a screenshot of the QL output in full screen mode, so that is what I did. This has never been a problem in the past (on this or my older iMac) so I doubt that has anything to do with whatever caused the thumbnail to be corrupted.

Even using your Untitled 2 version I get something unexpected if I click the expand-to-full-screen button in the default QL view -- the first time I do that I just get the default size thumbnail on a full screen black background; thereafter if I close the QL view, open it again, & click the button again I get the expected enlarged version.

If, instead of using that button, I manually drag out a corner of the the default QL view to enlarge it, on my iMac this works very smoothly & incrementally up to some size that varies depending on (I think) the size & complexity of the Affinity format file; beyond that it hesitates briefly & jumps from one size to a larger one & I do seem able to set it to any size smaller than that increment. Also, the default screen position of the initial QL view keeps changing -- it always opens at the same screen location for any given file but for another file (whether of an Affinity document or not) the location may be at a completely different place on the screen. I never saw anything like that on my older iMac, or for that matter on my new one until a few days ago.

All this makes me think there is something broken somewhere in the QL routines on this Mac but so far I have not been able to figure out what that might be or how to fix it. I have run Disk Utility's checks, done a safe boot to flush caches, reinstalled the OS, & tried several other things suggested by Apple Support, but nothing has changed, other than I am becoming increasingly frustrated that this new iMac isn't working as it should.

For now, I am just going to live with it as is. I bought AppleCare+ for it so I have 3 years of 'premium' support. I have already used phone support for a total of 5+ hours spent just to solve another obscure issue & I suppose I will eventually try the same for this one. I am just too stressed out to do that now.

[thomaso]

38 minutes ago, R C-R said:

All this makes me think there is something broken somewhere in the QL routines on this Mac

Instead investigating & testing you could just reset QL via Terminal.app to see if it helps:

qlmanage -r cache

https://osxdaily.com/2018/08/21/clear-quick-look-cache-mac/

[R C-R]

16 minutes ago, thomaso said:

Instead investigating & testing you could just reset QL via Terminal.app to see if it helps:

qlmanage -r cache

https://osxdaily.com/2018/08/21/clear-quick-look-cache-mac/

Thanks for the suggestion, but from what I can tell the com.apple.QuickLook.thumbnailcache file on my iMac running Catalina is already empty (probably due to the safe boot restart I tried) or for some reason nothing is being written to it as I assume it should be.

But I tried the qlmanage -r cache Terminal command anyway so I will see if this changes anything in the next few days.

[thomaso]

9 minutes ago, R C-R said:

I will see if this changes anything in the next few days.

If it has an effect you should see it immediately after the terminal command + logging out + logging in, for instance by QL-ing the file of your screenshot above.

You also could read & try other options available for the command "qlmanage" (e.g. without "cache"). Type "man qlmanage" to get them listed, for instance:

DESCRIPTION
     qlmanage allows you to test your Quick Look generators and manage Quick
     Look Server.

     The following usages are available:

     1.       qlmanage -r resets Quick Look Server and all Quick Look client's
              generator cache.

     2.       qlmanage -m gets all sort of information on Quick Look server
              including the list of detected generators.

     3.       qlmanage -t displays the Quick Look generated thumbnails (if
              available) for the specified files.

     4.       qlmanage -p displays the Quick Look generated previews for the
              specified files.

     5.       qlmanage -h displays extensive help.

[R C-R]

11 minutes ago, thomaso said:

If it has an effect you should see it immediately after the terminal command + logging out + logging in, for instance by QL-ing the file of your screenshot above.

Nothing changed -- the thumbnail & QL view still shows that weird double-scaled thing. 😕

I will try using some of the other qlmanage options at some point to see if that turns up anything of interest but for now I am really tired of fighting with this iMac to get it to work as I think it should. When things work as expected, it is joy to use -- many times faster & smoother than with the old iMac -- but I keep running into a variety of issues large & small (most apparently not directly related to Affinity) that is turning it into a toxic love/hate relationship.

[lepr]

1 hour ago, R C-R said:

What concerns me is that the thumbnail itself is not a preview of my file -- it looks like two different versions of it scaled to different sizes, with one of them only partially rendered.

Indeed. That's the first time I've seen a thumbnail corrupted like that.

1 hour ago, R C-R said:

As for the jpeg format of the screenshot [...] I doubt that has anything to do with whatever caused the thumbnail to be corrupted.

Of course  your screenshot being a JPEG has absolutely nothing to do with whatever caused the file's embedded thumbnail to be corrupted. I have no idea why you even bothered to write that.

 

 

 

 

[lepr]

2 minutes ago, R C-R said:

Nothing changed -- the thumbnail & QL view still shows that weird double-scaled thing. 😕

I will try using some of the other qlmanage options at some point to see if that turns up anything of interest but for now I am really tired of fighting with this iMac to get it to work as I think it should. When things work as expected, it is joy to use -- many times faster & smoother than with the old iMac -- but I keep running into a variety of issues large & small (most apparently not directly related to Affinity) that is turning it into a toxic love/hate relationship.

Fiddling with QL isn't going to change anything about that weird thumbnail. QL is not generating that thumbnail; QL is only displaying the already weird thumbnail that is in the Affinity document file.

[R C-R]

7 minutes ago, anon2 said:

Of course  your screenshot being a JPEG has absolutely nothing to do with whatever caused the file's embedded thumbnail to be corrupted. I have no idea why you even bothered to write that.

If it is not obvious, I was just trying to supply as much info as I could about what is happening on this particular iMac, hoping that someone might have an idea about its cause & cure. I included the info about my screenshot format setting because if I did not I thought someone might wonder if that had anything to do with it.