The MPEG-DASH Media Presentation Description (MPD) is an XML document containing information about media segments, their relationships and information necessary to choose between them, and other metadata that may be needed by clients.

In this post, I describe the most important pieces of the MPD, starting from the top level (Periods) and going to the bottom (Segments). In a later post, I cover common informative metadata. Other topics that I might cover include MPD events, in-band events (‘emsg’), and encryption (DRM).

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Most web browsers only support a few ancient image formats (mainly PNG, JPEG and GIF), but video formats have improved significantly since those formats were defined. Google is attempting to fix this with their WebP image format, based on VP8. Unfortunately, this only works with Google Chrome and Opera. Since what we want is to encode an image using the advancements in VP8 or h.264, I thought it would be interesting to try encoding single-frame videos and using them as images.

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I need to build Chromium on a machine that runs Fedora 20 today, and I had some trouble due to this error:

[12269/24399] LINK gles2_conform_support
FAILED: c++ -Wl,-z,now -Wl,-z,relro -Wl,--fatal-warnings -pthread -Wl,-z,noexecstack -fPIC -B/home/blong/workspace/chromium/src/third_party/binutils/Linux_x64 …

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