Digging HDMI Out Of UDP Packets

[Danman] was looking for a way to get the HDMI output from a camera to a PC so it could be streamed over the Internet. This is a task usually done with HDMI capture cards, either PCI or even more expensive USB 3.0 HDMI capture boxes. In his searches, [danman] sumbled across an HDMI extender that transmitted HDMI signals over standard Ethernet. Surely there must be a way to capture this data and turn it back.

The extender boxes [danman] found at everyone’s favorite chinese reseller were simple – just an Ethernet port, HDMI jack, and a power connector – and cheap – just $70 USD. After connecting the two boxes to his network and setting up his camera, [danman] listened in to the packets being set with Wireshark. The basic protocol was easy enough to grok, but thanks to the Chinese engineers and an IP header that was the wrong length, [danman] had to listen to the raw socket.

Once everything was figured out, [danman] was able to recover raw frames from the HDMI extenders, recover the audio, and stream everything to his PC with VLC. All the code is available, and if you’re looking for a way to stream HDMI to multiple locations on a network, you won’t find a better solution that’s this cheap.

RCA DSB772WE teardown shows that this cheap streaming box might have potential


[David Anders] wrote in to share some details of a cheap little gadget he picked up at his local Wal-Mart. He scored the RCA DSB772WE media streaming box for $48, and so far it looks like it could be a promising addition to his living room.

He started a project page for the box, detailing some of his findings thus far. The device is MIPS based and runs the Linux kernel version right out of the box. The networking components are based on the Broadcom BCM7615 chipset, though it looks to [David] that the Ethernet jack was removed at some point during production.

So far, he’s managed to get a serial console running on the device, along with an additional USB host connection. That’s about all the poking around he has done thus far, but seeing as the box can output a 1080p signal over HDMI, it could be a cheap substitute for an Apple TV or similar device.

If you happen to have one of these at home, or are planning on buying one, be sure to check out his project page and contribute any information you might be able to glean from it. We’re sure [David] would appreciate it, and we certainly look forward to seeing what else comes out of his hacking adventures.