Photoflow

[TheBlackCat]

Has anyone looked at the new Pictureflow replacement called Photoflow?  Apparently the original program was written as a tech demo, not as a real product.  As such it is very inefficient, written instead for clarity.  This new one, which was made by the same person and does basically the same thing, has been optimized for use on real-life mobile devices.  The main optimization, at least according to the blog post by the author, is that it only loads the few pictures just off-screen on either side in order to cut down on the memory footprint and startup time considerably.

There is more info on it here:
http://code.google.com/p/photoflow/
http://ariya.blogspot.com/2008/03/introducing-photoflow.html
http://ariya.blogspot.com/2008/03/photoflow-as-plasmoid.html

Will these improvements fix any of the problems people have been having with pictureflow (particularly not allowing music to play at the same time)?  

[bluebrother]

Will these improvements fix any of the problems people have been having with pictureflow (particularly not allowing music to play at the same time)?

No.

This is just an implementation of the same (a similar?) feature for other targets. To work on Rockbox it needs to be a Rockbox plugin. The page you linked is based on Qt, which is something completely different.

And the "problem" with not allowing music to play at the same time is simply related to the fact that all available memory is used for audio playback, so the available memory isn't enough for displaying the pictures the same time.

[TheBlackCat]

I understand that it isn't a rockbox plugin right now, but the previous version (pictureflow) was also qt-based  but was still ported to rockbox.  They may have different levels of dependence on qt which would make porting this version impossible, but I don't know so I thought I should point it out since it supposed to have all-around better performance.

[bluebrother]

"Porting" means to rewrite the program to work on the Rockbox API. This API has nothing in common with Qt (Qt is c++ while Rockbox it c), and an updated version of the original program doesn't make anything different for the Rockbox port. Also, Rockbox does not have dynamic memory which requires you to allocate each buffer you need in prior (i.e. when writing the application) and makes unused buffer simply a waste of memory. The only buffer plugins can use if they need lots of memory is the playback buffer, which in turn requires you to stop playback.

[NicolasP]

The PictureFlow Rockbox plugin is a rather heavily modified version of the Qt program. It already implements caching optimisations similar to what you describe. Those were secondary concerns for the program's original developer, but for the Rockbox port they were obviously at the top of the priority list, given the radically different constraints. Basically, although there is still plenty of room for improvement in PicturFlow, I don't see anything revolutionary for us in this new version of the PC program.

[TheBlackCat]

Alright, that makes sense.  I wasn't sure about the details of the relationship between the original photoflow and the rockbox port.