Update on what happened in WebKit in the week from February 11 to February 18.
Cross-Port 🐱
Multimedia 🎥
GStreamer-based multimedia support for WebKit, including (but not limited to) playback, capture, WebAudio, WebCodecs, and WebRTC.
Several multimedia-related optimizations landed this week, memory allocations were reduced in the video rendering code path and in the MediaStreamAudioDestinationNode implementation.
On the WebRTC fronts, the GstWebRTC backend has gained support for stats rate limiting support and the send/receive buffer sizes were adjusted.
The GStreamer video frame converter, used to show video frames in the canvas or WebGL, has been fixed to use the right GL context and now supports DMA-BUF video frames, too.
Added support to the eotf
additional MIME type parameter when checking for supported multimedia content
types. This is required by some streaming sites like YouTube TV.
The GStreamer-based WebCodecs AudioData::copyTo() is now spec compliant, handling all possible format conversions defined in the WebCodecs specification.
Infrastructure 🏗️
The WebKit ports that use CMake as their build system—as is the case for the GTK and WPE ones—now enable C++ library assertions by default, when building against GNU libstdc++ or LLVM's libc++. This adds lightweight runtime checks to a number of C++ library facilities, mostly aimed at detecting out-of-bounds memory access, and does not have a measurable performance impact on typical browsing workloads.
A number of Linux distributions were already enabling these assertions as part of their security hardening efforts (e.g. Fedora or Gentoo) and they do help finding actual bugs. As a matter of fact, a number of issues were fixed before all the WebKit API and layout tests with the assertions enabled and the patch could be merged! Going forward, this will prevent accidentally introducing bugs new due to wrong usage of the C++ standard library.
That’s all for this week!
