Home-theatre technology is constantly offering new ways to deliver picture and sound at the best possible quality. Improvements to the way content is displayed, the way it is stored and the way it is transmitted from device to device has continued to evolve the home-theatre set-up. New technologies, however, may not always work correctly with older equipment, and even brand-new equipment may not work at all, such as when HDMI devices display green screens.
HDMI and HDCP
HDMI stands for High Definition Multimedia Interface and is a completely digital means of providing high-definition content from a device to a display. HDMI has a companion technology associated with it that can often cause problems with some devices. This technology is HDCP, which stands for High Bandwidth Digital Content Protection. HDCP is designed to protect content from being recorded. It encrypts the content being sent through HDMI and checks to ensure that the device receiving the content is HDCP-certified and is not able to record the signal or transmit it to another device.
Each time that HDMI connects to a new device, HDCP needs to sync with that device. This process is called the handshake. Occasionally this handshake process will fail, preventing any video from displaying. This can result in static, a black screen, an error message or a green screen, depending on the device.
Some devices are not compatible with each other or with HDCP. Some TiVo devices, for instance, will not work with certain TVs, which can result in a green screen or similar error. Older high-definition televisions are often susceptible to compatibility problems when connected to newer equipment using HDMI.
If you are seeing the green screen as a result of a syncing problem, disconnect and reconnect the HDMI cable several times to reattempt the handshake. Some devices will need to be powered down completely before they will make a successful handshake. If the green screen persists, then the problem may be with compatibility. Check device manufacturers for firmware updates that will correct the problem. If there is no firmware updates or the problem persists, then switching from HDMI to component cables will eliminate HDCP and compatibility problems. The quality loss when switching from HDMI to component video is often unnoticeable.
On some TVs the green screen is used as an error message, indicating that the signal is not being received properly. If you are using devices that do not have any known compatibility problems, then the problem may be with the HDMI cable. Replacing the defective cable should allow the content to display properly.