Phonon

    From KDE UserBase Wiki
    Revision as of 22:30, 21 December 2010 by Periliocastrol (talk | contribs) (Created page with "* ''Configuración centralizada de audio y vídeo:'' La configuración de hardware e infraestructuras multimedia se ofrecen en un único y centralizado diálogo, de forma que las...")

    Si bien Phonon está desarrollado principalmente con la mente puesta en los desarrolladores de software, y el diseño se centra en la facilidad de desarrollo, Phonon también proporciona varias características y beneficios al usuario final.

    Características

    • Configuración centralizada de audio y vídeo: La configuración de hardware e infraestructuras multimedia se ofrecen en un único y centralizado diálogo, de forma que las aplicaciones no tienen que reimplementar diálogos de configuración especializados.
    • Diseño de propósito dirigido: En lugar de pedirte que selecciones salidas especiales de audio para aplicaciones especiales, las aplicaciones de Phonon describen que tipo de salida de sonido hacen (notificaciones, música, vídeo, comunicación), y te permiten seleccionar salidas para esas categorías individualmente.
    • Selección automatizada de dispositivos: La utilización de dispositivos extraíbles de audio y vídeo como auriculares USB o Bluetooth es casi omnipresente en la actualidad. Phonon funciona con la información y señales recibidas desde Solid, que es el subsistema de hardware de KDE, y automáticamente hace uso de los nuevos dispositivos.

    Troubleshooting

    No sound

    There are many possible reasons for no sound at all.

    Incorrect default ordering of devices

    Phonon automatically tries to order available audio devices using information available and a database with device information shipped with it. Unfortunately this doesn't always works, but look under Getting Involved for information on how you can help fix this.

    Missing device entries

    This can be caused by Solid or other system libraries reporting the same name for several devices, which makes Phonon unable to properly display these devices to you. Please see Getting Involved on how to help fix this.

    Unable to access audio device

    If your user account has insufficient permissions to access the audio device, Phonon will be unable to play sound. Please consult the documentation of your distribution on how to ensure that your user account is properly set up (make sure that your user account is a part of the audio user account group).

    Sound out of the wrong device

    This is related to the point above this. Also make sure that the correct device is listed at the top in the Sound and Video area of System Settings. In case an audio device isn't available (an USB-headset unplugged, for example), Phonon will attempt the next device in the list.

    Phonon causes a crash

    Please search on bugs.kde.org to see if the bug is already reported. If it isn't, please report it, and if it already exists but you have new information not already reported, please add your new information to the existing report.

    Devices from ~/.asoundrc or /etc/asound.conf are not listed

    Make sure you have a name hint set for your device. An example of a complete device entry, with a hint:

    pcm.softvolPhonon {
             type softvol
             slave.pcm "default:CARD=0"
             control {
                    name "Phonon"
                    card 0
             }
             min_dB -51.0
             max_dB 0.0
             resolution 100
             hint {
                    show on
                    description "My Soundcard with extra Volume Control"
             }
    }

    Backend libraries

    Phonon itself is just a thin shim, and makes use of backend libraries to provide the actual functionality.

    • Phonon-Xine: This is the first proper backend for Phonon, and is currently the most mature and recommended backend to use.
    • Phonon-VLC: VLC is a very popular cross-platform media player, and it is written using a multimedia library named libvlc, which we also use to power a backend for Phonon. This is also under active development, and is receiving a lot of work from both VLC and Phonon developers.
    • Phonon-GStreamer: GStreamer is a multimedia library from the GNOME project. This backend is not recommended due to a lack of volunteers for maintaining it.
    • Phonon-DS9: This is a native backend for Microsoft Windows utilizing DirectShow 9.
    • Phonon-QT7: This is a native backend for Mac OS X, utilizing QuickTime 7.
    • Phonon-MPlayer: This is a third-party backend for Phonon, utilizing the popular mplayer application for playback.
    • Phonon-NMM: This is an abandoned and unmaintained backend started by the Graphics Lab at Saarland University and Motama.

    Getting Involved

    There are several ways you can get involved as a user.

    • Reporting audio hardware: Download the soundcard.sh script and run it, and attach the output to bugs.kde.org. This enables us to add your hardware information to our audio device database.
    • Quality assurance: Simply run and use Phonon, and report bugs and irregularities to the developers.
    • Documentation: You can help expand this page and other Phonon documentation. It doesn't take much to help, and it helps!
    • Promotion: Spreading the word about KDE and Phonon is always welcome.
    • Appreciation: Encouraging words can help lift the spirits of weary multimedia developers way beyond the clouds, when faced with nasty bugs and other challenges. Positive emails, messages on IRC, beer, pizza, gadgets and other developer fuel is very welcome!