Proposal: Add thumbnails of different sizes to .kra files?

[Boudewijn Rempt]

On Mon, 6 Jun 2016, Dmitry Kazakov wrote:

> The only trouble I see with thumbnail generation is the speed. It would be great to see the speen benchmarks of saving a PNG of each size.

Well that needs checking indeed.

> People are complaining
> about Krita saving too slow :( I even heard a wish (during the KomMissia) to disable any preview and mergedimage.png saving into .kra to make the saving quicker.

That's just flat-out not going to happen.

> 
> 
> 
> 
> On Mon, Jun 6, 2016 at 3:44 PM, Boudewijn Rempt <boud at valdyas.org> wrote:
>       On Mon, 6 Jun 2016, Alvin Wong wrote:
>
>             Is that needed? I would imagine whatever plugins or programs would
>             already have known the absolute size they want in pixels, independent
>             of the dpi, and could just automatically take the closest thumbnail or
>             the mergedimage and scale it down accordingly.
> 
>
>       I don't know... Hidpi and Retina is still really confusing me across the board.
>
>             Perhaps you can also add a thumbnail of size 2048x2048 but I wonder
>             how much it would add to the file size...
>
>             By the way I remember seeing in the Krita git repo some scripts which
>             look like plugins for certain programs to extract the thumbnail, but I
>             can't seem to find them now. Does anyone know, other than the Windows
>             shell extension, what other file managers or programs currently
>             supports extracting thumbnails from Krita files/
> 
>
>       Code for Qt applications is in the kimageformats repo now, I moved
>       that some time ago. There are also scripts for nautilus and gnome.
> 
>
>             Best Regards,
>
>             Alvin
> 
>
>             2016-06-06 14:54 GMT+08:00 Boudewijn Rempt <boud at valdyas.org>:
>                   I think we can easily do this: but maybe we should at the same time
>                   add thumbnails with a @2 extension to prepare for hidpi and retina
>                   displays?
> 
>
>                   On Mon, 6 Jun 2016, Alvin Wong wrote:
>
>                         Hi,
>
>                         I would like to suggest Krita add (uncropped) thumbnail images of
>                         different sizes to the file to allow faster extraction of thumbnails
>                         by external applications.
>
>                         There is currently one preview.png which is at maximum 256x256, so
>                         generating thumbnails larger than that would require scaling down from
>                         the mergedimage.png which could be very large and may take a
>                         comparatively long time to process. Even though the actual time per
>                         file might not be much, it could add up for a lot of files.. Also, the
>                         preview.png is cropped to the non-transparent region
>                         (https://bugs.kde.org/show_bug.cgi?id=363968) which makes things a bit
>                         weird and inconsistent.
>
>                         I think having thumbnails for the sizes (maintaining aspect ratio) of
>                         256x256 and 1024x1024 would suffice, but boud suggested having 512x512
>                         might be nice too. Adding in these sizes means that, for thumbnails
>                         equal to or below the available sizes, they can be extracted and
>                         optionally scaled down from those instead of scaling down from the
>                         mergedimage.png. Obviously, sizes larger than that would still require
>                         using the mergedimage.png, but hopefully it would be quite rare for an
>                         application to request for thumbnails larger than 1024x1024... (4K
>                         displays aren't popular yet... right?)
>
>                         For the record, according to this MSDN page
>
>                         (https://msdn.microsoft.com/en-us/library/windows/desktop/cc144118(v=vs.85).aspx)
>                         Windows asks for the sizes 32/96/256/1024.
>
>                         I am asking for this as the developer of the Windows Shell Extension.
>
>                         Any suggestions?
>
>                         Best Regards,
>
>                         Alvin
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> 
> 
>
>                   --
>                   Boudewijn Rempt | http://www.krita.org, http://www.valdyas.org
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> 
>
>       --
>       Boudewijn Rempt | http://www.krita.org, http://www.valdyas.org
>       _______________________________________________
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>       https://mail.kde.org/mailman/listinfo/kimageshop
> 
> 
> 
> 
> --
> Dmitry Kazakov
> 
>

-- 
Boudewijn Rempt | http://www.krita.org, http://www.valdyas.org