grilo: easy access to online multimedia content (linuxcon europe 2012)

Grilo: Easy Access to Online Multimedia Content

LinuxCon Europe 2012, Barcelona

Juan A. Suarez Romero <[email protected]>


Introduction

Grilo: Easy Access to Online Multimedia Content LinuxCon Europe 2012, Barcelona

About me

Juan A. Suárez RomeroComputer engineer, Coruña UniversityWorking at Igalia since 2007Experience in multimediaInvolved in Maemo and MeeGoCo-author of MAFW


Outline

1 Current problems

2 Grilo

3 Conclusions

4 Thank you!



Current problems


Many sources of content

Online/offline sourcesDifferent protocol/APISources that do notprovide content(meta-information)


Many different devices

Different screen sizesDifferent hardwarecomponentsDifferent platforms


Current approach

Develop one application per serviceEach application with different UXNot easily scalable: new sources require new applicationsExpensive maintenance

In some cases, one application attending more than oneservice

Services of the same type (e.g., Photo storage service)Define a common layer between application and the service

Not shared effort! Reinventing the wheel all time


What we need?

Stop reinventing the wheel!

Platform-level solution for accessing multimedia contentProvide homogeneous access to all contentScalable with new sources of informationCollaboration!Consistent user experience

Users care about the content, not the provider



Grilo


What is Grilo?

Framework focused on making discovery and browsingeasy for application developers

A single, high-level API for all the sourcesA collection plugins that provides access to the sourcesAn extendable system to provide more plugins

http://live.gnome.org/Grilo



Architecture overview


Media types and Keys

Collection of keys andvaluesSeveral keys provided bycore: title, URL, author, . . .

Plugins can extend themwith new keys

Support for multiplevaluesSupport for relationsbetween keys


Plugins and Sources

Key component of thesystemPlugins are dynamicallyloaded by corePlugins create one or moresourcesSources support multipleoperations

Browse, Search, Store,Remove, . . .

All operations are optional


Plugins and Sources

Sources perform two mainroles:

Provide new mediacontentEnrich already existentmedia content

Sources collaborate amongthem to solve the requests


Example of collaboration

Developer wants to show content from UPnP server andplay itThey need the url to play, a title and a thumbnail to show

1 Perform the request through core API2 Core checks if the requested keys are supported by the

sourcethumbnail is not supported by UPnP source

3 Checks which sources are able to resolve thumbnail keyCoverArt source is able toBut it requires to know two keys: artist and album


Example of collaboration

4 Core checks if those required keys are supported byoriginal UPnP source

If not, repeat the process as in the case of thumbnail5 Perform the request in the UPnP source with the keys

requested plus the new keys6 When the results arrive, send them to CoverArt source to

include the thumbnail7 Send the final results to application

Developer only needs to deal with one provider


Implementing applications

Main language is COther languages supported through gobject introspection(Python, Javascript, Vala, . . . )

Support for C++ (grilomm)Some initial support for Qt/QML


Code example

1 # ! / usr / b i n / python23 import sys4 from gi . r e p o s i t o r y import Grl56 def main ( argv ) :7 i f len ( argv ) < 1 :8 print " Usage : make_l is t . py <se arc h_ te x t >"9 return 1

1011 Grl . i n i t ( [ ] )12 r e g i s t r y = Grl . Reg is t ry . g e t _ d e f a u l t ( )13 r e g i s t r y . l o a d _ a l l _ p l u g i n s ( )14 keys = [ Grl .METADATA_KEY_DURATION,15 Grl . METADATA_KEY_TITLE,16 Grl .METADATA_KEY_URL]17 opt ions = Grl . OperationOptions . new( None)18 opt ions . se t_count ( 2 0 0 ) ;19 r e s u l t s = Grl . mult iple_search_sync ( None , argv [ 0 ] , keys , opt ions )2021 print " #EXT3MU"22 for media in r e s u l t s :23 i f i s i n s t a n c e ( media , Grl . MediaAudio ) :24 print " #EXT3INF : " + s t r ( media . get_durat ion ( ) ) + " , " + media . g e t _ t i t l e ( )25 print media . g e t _ u r l ( )2627 i f __name__ == " __main__ " :28 main ( sys . argv [ 1 : ] )


Implementing plugins

Plugins must be written in CAdding support for writing plugins declaratively (in XML)Adding support for other languages (Lua)



Conclusions


Resources

Wikihttp://live.gnome.org/Grilo

Source codehttp://git.gnome.org/browse/grilohttp://git.gnome.org/browse/grilo-pluginshttp://git.gnome.org/browse/grilomm

IRC#grilo at irc.gnome.org

Mailing listhttp://mail.gnome.org/mailman/listinfo/grilo-list

Do not miss our booth in ground floor (in front of Rossiniroom)



http://git.gnome.org/browse/grilo

http://git.gnome.org/browse/grilo-plugins

http://git.gnome.org/browse/grilomm

http://mail.gnome.org/mailman/listinfo/grilo-list

http://mail.gnome.org/mailman/listinfo/grilo-list


Thank you!


Images used in this presentation

Hard Disk Icon by Mazenl77 (CC Attribution)http://www.iconspedia.com/icon/hard-disk-1600.html

Memory Card Icon by Custom Icon Design Studiohttp://www.gettyicons.com/free-icon/103/pretty-office-2-icon-set/free-memory-card-icon-png

Vimeo, Flickr, Jamendo, YouTube and UpnP logos under copyright of their ownbrands


http://www.iconspedia.com/icon/hard-disk-1600.html

http://www.gettyicons.com/free-icon/103/pretty-office-2-icon-set/free-memory-card-icon-png

http://www.gettyicons.com/free-icon/103/pretty-office-2-icon-set/free-memory-card-icon-png

grilo: easy access to online multimedia content (linuxcon europe 2012)

Technology

adding support

easy access

provider grilo

plugins

sources

service

grilo

keys