Hello ,
I am using plasma 5 on arch, while i have previews for images and videos, I would really like to have preview for Krita files (.Kra)
I am an artist and my work involves huge amount of kra, ora and psd files, so it would be great to have preview for these.
I am sure other artists using kde will also benefit from this feature.

Please let me know if I need to file a bug report ( wishlist which i'll do in a moment) or if there is any other workaround for getting the previews

your help is really appreciated.

thank you

The KDE applications can show a thumbnail for a file if there is a thumb creator plugin installed for the file type.

The KDE is using freedesktop specifications: http://freedesktop.org/wiki/Specifications/ and there the specification for storing file thumbnails: http://specifications.freedesktop.org/thumbnail-spec/thumbnail-spec-latest.html.

KDE api for the thumbnailers:

KDE4: http://api.kde.org/4.x-api/kdelibs-apid ... eator.html
KF5: http://api.kde.org/frameworks-api/frame ... eator.html

There is a thumbnailer for the .kra: https://git.reviewboard.kde.org/r/121886/ . The Arch package 'calligra-krita' has it for the KDE4. The thumbnailer probably will be ported to the KF5 when the Krita will be ported to the KF5. As a workaround you could use the Dolphin-KDE4. Arch package: dolphinpart4.



The bug reports will be useful - same kind of - KF5 missing thumbnailers:
- https://bugs.kde.org/show_bug.cgi?id=351894
- https://bugs.kde.org/show_bug.cgi?id=351913

Hi Rog131,

Thank for the links and suggestion,
i know that there is thumbnail support for kra in dolphin 4, I was hoping for the thumbnails in new dolphin, I will wait till krita is completely ported to kf5,
If this matters - I have built krita kf5 port ( master from the krita git) from the git too but that doesn't enable or bring back the option in dolphin.

Also what about other file types, i recently asked help about webp and it was solved check this review apparently the file type was not recognized properly, while discussing about that I saw photoshop filetype mentioned in their so i asked about thumbnails for psd , the good person replying to me tried to get that sorted with this patch here but it didn't get the psd thumbnails. Is there any other way to get those.

And what about .ORA do I need to do something to make it work?

Thank you very much for your reply and time.


thank you

P.S. just as an additional information, with nemo in cinnamon I used a script and thumbnailer entries for .ORA and .KRA ( by David Revoy) and photoshop thumbnailer that did the trick to generate the thumbnails is there something similar in dolphin. Pardon me if I seem silly or stupid.

kamathraghavendra wrote:If this matters - I have built krita kf5 port ( master from the krita git) from the git too but that doesn't enable or bring back the option in dolphin.

Works fine here with krita's git master from about 2 weeks ago. I can see previews for .kra and .ora files in dolphin 15.08.3 (i.e. the KF5 version).
Previews for .psd files are shown as well (by the standard image thumbnailer in kio-extras5), but a test file I created with Krita showed as completely black. It is shown correctly in the KDE4 version, so this seems to be a bug/regression, or it's just still work in progress... It opens as completely black in other KF5 applications as well.

Did you enable the preview for .kra files in dolphin's settings? (General->Previews)
Do you have the file /usr/share/kservices5/krita_kra_thumbnail.desktop? Maybe it is installed in the wrong location...
Try running "kbuildsycoca5 --noincremental" to recreate the system configuration cache.

Hi wolfi323,

(by the standard image thumbnailer in kio-extras5

I have kio-extras ( arch version) but still I don't have psd thumbnails, the person trying to solve my problem ( check the git review link I shared) too doesn't have it so this is not only me.

Did you enable the preview for .kra files in dolphin's settings? (General->Previews)

I don't get this option

Do you have the file /usr/share/kservices5/krita_kra_thumbnail.desktop? Maybe it is installed in the wrong location...

No I searched I have the file in build directory but not in usr/share, did you install krita in /usr
manually copying it to the location you mentioned crashes dolphin when I go to configuration

Try running "kbuildsycoca5 --noincremental" to recreate the system configuration cache.

I tried to but that is giving me error, also i thought it was not necessary for krita

kamathraghavendra wrote:
P.S. just as an additional information, with nemo in cinnamon I used a script and thumbnailer entries for .ORA and .KRA ( by David Revoy) and photoshop thumbnailer that did the trick to generate the thumbnails is there something similar in dolphin. Pardon me if I seem silly or stupid.

Looking how the G side is doing it: http://moritzmolch.com/1749

So they are using unzip - hmm - writing a generic KDE thumbnailer plugin aka keneric.

The keneric is executing a short script:

Code: Select all

#!/bin/sh
# Usage: stripPicture fileaname

fullname="$1"
filename=$(basename "$1")
extension="${filename##*.}"

exportPicture=$HOME/.config/keneric/UseThisPicture.png

# thumbnail options by extension type
case "$extension" in


      kra)
      unzip -p "$fullname" preview.png > "$exportPicture"
      exit
      ;;
     
      ora)
      unzip -p "$fullname" Thumbnails/thumbnail.png > "$exportPicture"
      exit
      ;;

      *)
#     case trap
      exit
     
esac

The script is stripping the thumbnail to the $HOME/.config/keneric/UseThisPicture.png and the plugin is 'converting' the png image to the thumbnail.

Seems to work...


Full image: http://imgur.com/3PJIS9s

but as 'wolfi323' wrote the proper KDE thumbnailer is coming.


... and adding to the KDE-Apps: http://kde-apps.org/content/show.php/Ke ... ent=174485

----------------- EDIT -------------------

Now (2016-08-03) the Keneric is at: KDE Look - Other KDE Extensions : https://www.kde-look.org/browse/cat/157/ord/latest/ --> https://www.kde-look.org/p/1080815/

kamathraghavendra wrote:

(by the standard image thumbnailer in kio-extras5

I have kio-extras ( arch version) but still I don't have psd thumbnails, the person trying to solve my problem ( check the git review link I shared) too doesn't have it so this is not only me.

As indicated, there seems to be a general issue with .psd files. As I wrote, the thumbnail is just completely black here, and the same happens when opening a .psd file with *any* KF5 application. I tried with kolourpaint, okular, gwenview and showFoto/digikam.

Do you have the file /usr/share/kservices5/krita_kra_thumbnail.desktop? Maybe it is installed in the wrong location...

No I searched I have the file in build directory but not in usr/share, did you install krita in /usr
manually copying it to the location you mentioned crashes dolphin when I go to configuration

Well, if it is not there, this explains why you don't have the option.

I didn't copy it manually, but I use openSUSE's build macros which pass some installation path options to cmake. In this particular case, try to add -DSERVICES_INSTALL_DIR=/usr/share/kservices5 to the cmake command line...

And you need the actual thumbnailer as well: /usr/lib64/qt5/plugins/kritathumbnail.so
For this try -DKDE_INSTALL_PLUGINDIR=/usr/lib64/qt5/plugins (or whereever your Qt5 plugins are located...)
Although dolphin should not crash if that's not there. But maybe it tried to load the KDE4 version instead (causing a Qt4/Qt5 clash).

Try running "kbuildsycoca5 --noincremental" to recreate the system configuration cache.

I tried to but that is giving me error, also i thought it was not necessary for krita

It shouldn't be necessary, but it might happen that the cache is outdated and (new) plugins are therefore not noticed. That's not specific to Krita, but rather a general KDE thing.
In your case it won't help though, as apparently the plugin is not installed (to the correct location) in the first place.

But what error did you get? It's quite normal that it prints some warnings about certain .desktop files though (deprecated stuff being used e.g.).

Linking to https://bugs.kde.org/show_bug.cgi?id=356227


PSD thumbnails with the Keneric 0.3 - little help with the ImageMagick

1) Disabling the kio-extras PSD thumbnailing

The kio-extras psd thumbnailer is blocking the Keneric PSD thumbnailer.

Copying the /usr/share/kservices5/imagethumbnail.desktop to the ~/.local/share/kservices5/imagethumbnail2.desktop
Removing the 'image/vnd.adobe.photoshop' from the 'MimeType' list of the ~/.local/share/kservices5/imagethumbnail2.desktop


Full: http://i.imgur.com/pyJR0tm.png


and adding 'Not PSD' to the ~/.local/share/kservices5/imagethumbnail2.desktop

Code: Select all

Name=Images (GIF, PNG, BMP, ... Not PSD)

2) Adding PSD thumbnailer to the 'Keneric' thumbnailer.

Making ~/.local/share/kservices5/kenericpsd.desktop

Code: Select all

[Desktop Entry]
Type=Service
Name=Photoshop images (Keneric)
Name[x-test]=xxPhotoshop imagesxx

X-KDE-ServiceTypes=ThumbCreator
MimeType=image/vnd.adobe.photoshop;

X-KDE-Library=keneric
CacheThumbnail=true


Adding few lines to the /usr/local/bin/stripPicture
Using as template the Keneric-0.3 readme.html - Examples/Windows metafiles .wmf

Code: Select all

      image/vnd.adobe.photoshop)
      convert "$fullname[0]" png:"$exportPicture"
      exit
      ;;


More of the ImageMagick & Convert with flatten:
- http://www.imagemagick.org/discourse-se ... hp?t=11169
- http://www.imagemagick.org/discourse-se ... hp?t=15768
- https://davidwalsh.name/export-photoshop-file-image


3) Enabling

Disabling the standard 'Images' thumbnailer.
Enabling the 'Not PSD Images' thumbnailer.
Enabling the 'Keneric' PSD Thumbnailer.


Full: http://i.imgur.com/w32dVnb.png


Sample PSD pictures: http://ito.hkbu.edu.hk/eng/training/cou ... ample.html

HI wolfi323

even when I manually copied the .desktop file in kservices5 directory the thumbnails didn't appear, I got the option in preview setting in dolphin though, I guess this is because there is no thumbnailer in /usr/lib64/qt5/plugins/kritathumbnail.so

however I talked to Boud ( krita developer) he said that the thumbnailers can be added to upstream and are not dependent on krita , he has added a review request for this here -> https://git.reviewboard.kde.org/r/126674/ and here-> https://git.reviewboard.kde.org/r/126675/

I think it will not be in dolphin even for users who don't install krita

regarding photoshop thumbnails I am trying what Rog131 suggested, I hope this come to dolphin as well

kamathraghavendra wrote:even when I manually copied the .desktop file in kservices5 directory the thumbnails didn't appear, I got the option in preview setting in dolphin though, I guess this is because there is no thumbnailer in /usr/lib64/qt5/plugins/kritathumbnail.so

Yes, as I wrote.

/usr/lib64/qt5/plugins/kritathumbnail.so is the actual thumbnailer. the .desktop file just describes which thumbnailer to use for that filetype.

You probably need to copy that to the correct place manually as well.

however I talked to Boud ( krita developer) he said that the thumbnailers can be added to upstream and are not dependent on krita , he has added a review request for this here -> https://git.reviewboard.kde.org/r/126674/ and here-> https://git.reviewboard.kde.org/r/126675/

I think it will not be in dolphin even for users who don't install krita

Right.
This should make previews for .kra and .ora files available without Krita(5) installed.

regarding photoshop thumbnails I am trying what Rog131 suggested, I hope this come to dolphin as well

The psd thumbnailer *is* in kio-extras already, psd files are actually handled by the general image thumbnailer (imagethumbnail.so).

But again, there apparently is a general problem with opening PSD files in KF5 at the moment, they also show up completely black here when trying to open it with any other KF5 application (e.g. gwenview5 or kolourpaint5), not only in Krita5 or the thumbnailer.
So it's rather a bug in the psd plugin in kimageformats, I'd say.

wolfi323 wrote:But again, there apparently is a general problem with opening PSD files in KF5 at the moment, they also show up completely black here when trying to open it with any other KF5 application (e.g. gwenview5 or kolourpaint5), not only in Krita5 or the thumbnailer.
So it's rather a bug in the psd plugin in kimageformats, I'd say.

PS, I found the bug and fixed it, see here:
https://git.reviewboard.kde.org/r/126684
With this, thumbnails for PSD files work fine here, and I can also load them in KF5 based okular, gwenview, or kolourpaint. (haven't tried krita, as that just crashes here when loading any file at the moment)

The decoding length "overflowed", so depending on the image size RLE compressed psd files were loaded correctly (images smaller than 256x256 pixels), turned completely black or were not able to be loaded at all (because the RLE decoding failed).

Hi wolfi323

thank you for your time and thanks for fixing this,
now eagerly awaiting it to ship in next versions

thank you once more

My fix is in, this should work with Frameworks 5.19.0.
You might have to delete ~/.cache/thumbnails/ though, if there's already a thumbnail in there (black or otherwise broken), it won't get regenerated.

Also note that kimageformats's psd plugin does not support all types of psd files, only RGB (not greyscale e.g.). And only uncompressed or RLE compressed, not ZIP.
But that's how it was in KDE4 too...

Btw, the .kra/.ora thumbnailer has been submitted to kio-extras too today, so will be in KDE Applications 16.04.

I just moved over to Dolphin for good about 6 months ago. I was wondering what the process is for requesting a file type being supported in preview. I was kinda hoping there was a plugin methodology for preview where a script could gen the image for the preview, but it doesn't seem to work that way on the surface. I'm a KiCad user and would like to have preview work with kicad_mod, kicad_pcb, pro, and sch files. They are simple to parse and would be similar to svg files. And pointers?

rhowlett wrote:I was wondering what the process is for requesting a file type being supported in preview. I was kinda hoping there was a plugin methodology for preview where a script could gen the image for the preview, but it doesn't seem to work that way on the surface.

It (or rather KIO) does indeed use a plugin methodology.
The thumbnailers (plugins) are binaries though, with a .desktop file in /usr/share/kservices5 that describes them.

But there is a generic thumbnailer ("keneric"), that uses arbitrary scripts to generate the thumbnails. See Rog131's post (from Dec 3rd) for that:
viewtopic.php?f=223&t=129633#p346752