Here's one of the easiest capture solutions for getting HDMI data into your computer or Raspberry Pi, really any system with a USB port..
Use this capture device to convert a video signal from a camera (or another device) into a digital format your computer can recognize. Its trivially easy to use: connect one end to an HDMI output up to 1080p. Connect the other end to a mainboard USB port.
This dongle doesn't have the quality of $100 or $1000 converters, but for every day HDMI capture it works very well for the price! No drivers to install. Plug and play with Windows, Mac, Linux - shows up like a video source and a great option for streaming data from game consoles.
Supports up to 1920x1080 (1080p) up/down conversion. Please note that we removed the heat-sink in the disassembled photo, normally there is a heat sink bonded on.
Product Dimensions: 65.0mm x 30.0mm x 15.0mm / 2.6" x 1.2" x 0.6"