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Showing posts from June, 2017

Chromecast audio: mirroring, streaming, authenticating

I was curious about what the Chromecast audio is and how it works - both in terms of hardware and software. After a lot of needless thrashing about, I realized that the wikipedia page has the specifications for the system on a chip, though the ifixit teardown is more detailed and also points out that the Chromecast and Chromecast audio basically have the same system-on-a-chip. Interestingly, the Synology NAS also has a Marvell Armada system. Exploitee.rs says that the system runs a modified Android system.

I was most curious about was how the software works: specifically, when I play music through the chromecast audio what is the flow of data? My web-search-fu failed me, and could not get any descriptions of this that went beyond user-level, google marketing speak. What I gather is that there are two modes of data transfer: mirroring and streaming.

Mirroring takes the audio data stream playing from a computer (laptop, smart phone, iPad) and redirects it to the Chromecast. Software on …