BBC & 4K

BBC R&D was lucky enough to be granted access to this year’s London New Year’s Eve Fireworks to undertake a test shoot of the festivities in “4k” Ultra High Definition (UHDTV) and Higher Dynamic Range (HDR). This blog describes the benefits of HDR and why it may be an important part of a future television system.

What is HDR?
BBC R&D is investigating a wide range of technologies that may feature in the next generation of broadcast. These may include a higher spatial resolution (more pixels on the screen), a higher frame rate (more pictures per second), wider colour gamut (more colours than before), and higher dynamic range.

As BBC R&Ds Andrew Cotton recently wrote in an article for DVB Scene – “Those who have been lucky enough to see High Dynamic Range (HDR) TV pictures cannot help but be blown away by their impact. They are more realistic, more colourful, subjectively sharper and more engaging than standard dynamic range (SDR) images. That is not just marketing: the “Hunt effect” is a well-known phenomenon whereby the colourfulness of an object increases with luminance; and video engineers have always known that increasing the contrast of an image makes it appear sharper as the gradient of edges increases. So it is no wonder that high brightness HDR images are so eye-catching.”

The dynamic range of a video signal is the range between the lowest and highest light level. Those who commonly take pictures on a digital camera may be familiar with the problem of capturing both bright and dark parts of the picture and maintaining high levels of detail in both of these areas. To overcome the shortcomings of the image sensors, many digital cameras and smart phones come equipped with a “HDR mode”.

For more information see the BBC Blog.