Tag / multimedia

  • December 29, 2016 - Arun Raghavan

    Playback Synchronization & Video Walls with GStreamer

    Hello again, and I hope you’re having a pleasant end of the year (if you are, you might want to consider avoiding the news until next year). In a previous post, I wrote about synchronized playback with GStreamer, and work on this has continued apace. Since I last wrote about it, a bunch of work has been completed: Added support for sending a playlist to clients (instead of a single URI), Added the ability to start/stop playback, Cleaned up the API considerably to improve the potential for it to be included upstream, Turned the control protocol implementation into an interface to remove the necessity to use the built-in TCP server (different use-cases might want different transports), Improved overall robustness of code and documentation, Introduced an API for clients to send the server information about themselves, and finally Added an API for the server to send video transformations for each specific client to apply before rendering. […]

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  • The Linux Kernel Summit Media Workshop was held on October 26, 2015 in Seoul, South Korea. We had 21 attendees from various companies and places in the world gather to discuss the current state of Linux Media and the challenges that need to be overcome to push these technologies into the future. This article will cover the major topics that were discussed during this workshop and the decisions that were made about the direction of this community.   Codec API Improvements Currently, Video4Linux version 2 (V4L2) memory to memory devices uses the Stream API to handle coders/decoders (codecs), but it might be time for us to develop a Frame API to handle newer devices. Stream API The original V4L2 codec API was developed along with the Exynos codec driver. Since the device implements high-level operations in hardware, the resulting API was high-level as well with drivers accepting unprocessed raw streams. […]

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  • This article contains a summary of the discussions that took place at the Media Controller Workshop in Espoo, Finland from July 29 – 31, 2015. A more detailed breakdown of these discussions can be found on Linux TV. This is the first  workshop dedicated to the Linux Media Controller. It follows a v4l summit that took place back in 2010 in Finland that established the current foundation for the media controller. This was aimed at properly satisfying the needs of reporting pipelines on the smartphone System on a Chip (SoC). The focus of this year’s workshop was to clarify the kernel→userspace interfaces and extend the Media Controller to be used on other subsystems that need to represent graphs like Linux Digital Video Broadcasting (DVB), Advanced Linux Sound Architecture (ALSA), and Industrial I/O (IIO). Samsung had a strong representation at this workshop, including Shuah Khan and Mauro Carvalho Chehab from the […]

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