[digiKam-users] Version 6 idea: store thumbnails as JPEG instead of PGF

[Tac Tacelosky]

I've been playing around with using the digikiam database as the back-end to a web-based view of my photos.  Using MySQL as the backend database makes this a pretty natural idea.

The thumbnails are stored in the database in PGF format.  Although there are some advantages to using this, I'd like to propose that version 6 have the option to store the thumbnail images in jpeg, even though it'll take up more space.  

I'm trying to avoid re-creating the thumbnails in the web view, and I can't find anything that will convert PGF to JPEG or PNG within PHP, the language I'm using for the web-based ui.

Thanks for your consideration.

Tac

[Gilles Caulier-4]

Hi,

Typically, using JPEG as a really disadvantage about thumbnail quality, especially with Hdpi screen. For that, I'm not favorable to propose JPEG as thumbs storage in DB.

But i still open. Your request is to create a digiKam back-end to a web-based view photo collections. There are other standards for the web, emerging step by step, based on wavelets compression, as Webp or Heic.

https://www.cnet.com/news/google-offers-jpeg-alternative-for-faster-web/

https://www.cnet.com/news/google-mozilla-av1-photo-format-could-outdo-aging-jpeg/

Both Webp and Heic are supported by ImageMagick, so PHP must do the conversion in background :

https://www.imagemagick.org/script/formats.php

In other words, we need space optimization, quality and speed. For the 2 first ones, JPEG is not the right solution.

Else about PGF, which is not supported by ImageMagick, a simple converter exists with libpgf, and can be called easily by PHP on you web server...

https://sourceforge.net/p/libpgf/code/HEAD/tree/trunk/pgf/

Best

Gilles Caulier

[Tac Tacelosky]

Thanks, Gilles,

Poking around the source code, I see that at one point there was some support for storing JPEG thumbnails, but it's been hard-coded to PGF files:

https://github.com/KDE/digikam/blob/9330f9c1e25ce754f374abac840bef2521a032ca/libs/threadimageio/thumbnailcreator.cpp#L737-L762

Unfortunately, my C skills are ancient, and my sys-admin skills are pretty weak as well, so I haven't been able to get the PGF console command to work on my 64-bit Ubuntu installation.  I think I've compiled the pgf library okay, but the pgf console tool fails on finding freeimageplus, even after installing it (well, I think I installed it).

So I'll keep playing around with alternative solutions to at least prototype my idea.

Has anyone else worked on a web-based interface to DigiKam?  I'll like to brainstorm about it, is another thread on this forum the right place to start?

Tac
 

On Sun, Mar 11, 2018 at 1:01 PM, Gilles Caulier <[hidden email]> wrote:

Hi,

Typically, using JPEG as a really disadvantage about thumbnail quality, especially with Hdpi screen. For that, I'm not favorable to propose JPEG as thumbs storage in DB.

But i still open. Your request is to create a digiKam back-end to a web-based view photo collections. There are other standards for the web, emerging step by step, based on wavelets compression, as Webp or Heic.

https://www.cnet.com/news/google-offers-jpeg-alternative-for-faster-web/

https://www.cnet.com/news/google-mozilla-av1-photo-format-could-outdo-aging-jpeg/

Both Webp and Heic are supported by ImageMagick, so PHP must do the conversion in background :

https://www.imagemagick.org/script/formats.php

In other words, we need space optimization, quality and speed. For the 2 first ones, JPEG is not the right solution.

Else about PGF, which is not supported by ImageMagick, a simple converter exists with libpgf, and can be called easily by PHP on you web server...

https://sourceforge.net/p/libpgf/code/HEAD/tree/trunk/pgf/

Best

Gilles Caulier

[Gilles Caulier-4]

I github, there is a project to build a PHP based web interface to digiKam. I Never tested.

https://github.com/mehdilauters/digikamWebUi

But why you need a web interface when a UPNP/DLNA solution already exists ?

Gilles Caulier

2018-03-14 15:47 GMT+01:00 Tac Tacelosky <[hidden email]>:

Thanks, Gilles,

Poking around the source code, I see that at one point there was some support for storing JPEG thumbnails, but it's been hard-coded to PGF files:

https://github.com/KDE/digikam/blob/9330f9c1e25ce754f374abac840bef2521a032ca/libs/threadimageio/thumbnailcreator.cpp#L737-L762

Unfortunately, my C skills are ancient, and my sys-admin skills are pretty weak as well, so I haven't been able to get the PGF console command to work on my 64-bit Ubuntu installation.  I think I've compiled the pgf library okay, but the pgf console tool fails on finding freeimageplus, even after installing it (well, I think I installed it).

So I'll keep playing around with alternative solutions to at least prototype my idea.

Has anyone else worked on a web-based interface to DigiKam?  I'll like to brainstorm about it, is another thread on this forum the right place to start?

Tac
 

On Sun, Mar 11, 2018 at 1:01 PM, Gilles Caulier <[hidden email]> wrote:

Hi,

Typically, using JPEG as a really disadvantage about thumbnail quality, especially with Hdpi screen. For that, I'm not favorable to propose JPEG as thumbs storage in DB.

But i still open. Your request is to create a digiKam back-end to a web-based view photo collections. There are other standards for the web, emerging step by step, based on wavelets compression, as Webp or Heic.

https://www.cnet.com/news/google-offers-jpeg-alternative-for-faster-web/

https://www.cnet.com/news/google-mozilla-av1-photo-format-could-outdo-aging-jpeg/

Both Webp and Heic are supported by ImageMagick, so PHP must do the conversion in background :

https://www.imagemagick.org/script/formats.php

In other words, we need space optimization, quality and speed. For the 2 first ones, JPEG is not the right solution.

Else about PGF, which is not supported by ImageMagick, a simple converter exists with libpgf, and can be called easily by PHP on you web server...

https://sourceforge.net/p/libpgf/code/HEAD/tree/trunk/pgf/

Best

Gilles Caulier

[Eneka Mujika]

Good Morning
Sorry for the writing, it's a Google translator.

I use Digikam as a home user, not a professional user. I think it's a great
program.
Using php I like to do kml for Google Earth with tour and so on.
I have the same problem with the thumbnails.
Does any page explain how to use libPGF with php?

Congratulations for Digikam.

P.S. Hello Tac, I also play with the web,
Do we change sql's?



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