This article – based on an EBU contribution to the WBU-TC Digital Radio Systems Handbook – introduces the concept of Internet Radio (IR) and provides some technical background. It gives examples of IR services now available in different countries and provides some guidance for traditional radio broadcasters on how to adapt to the rapidly changing multimedia environment.

With the introduction of digital transmission, broadcasters have experienced significant problems with cascaded audio coding in the broadcast chain. It has been found that cascading different codecs can result in an overall degradation in the sound quality that many listeners find objectionable. A comprehensive investigation of this problem has been conducted by members of the EBU project group B/AIM.

This article, based on a presentation given at IBC-2005, describes typical cascades of codecs found in radio broadcast chains, and aims to identify the most critical combinations. The intention is to guide broadcasters in deciding which codec combinations should be avoided in order to maximize the sound quality.

Digital video coding standards offer flexibility in their encoding techniques and enable coding efficiency improvements, in compliance with the standard, over a period of time. The MPEG-2 video coding standard [1] employs the adaptive DCT coding scheme with motion-compensated prediction. The amount of overhead information, including motion vector codes and coding modes, is often large for critical HDTV sequences at lower bitrates.

NHK’s new coding method [2] – conforming to the MPEG-2 Main Profile – significantly reduces the amount of overhead information and makes digital HDTV services possible at lower bitrates, while maintaining compatibility with conventional digital broadcast receivers.

TPEG technology has been quite a long while in the making – compared with some other technology developments. This article explains how the development of a worldwide standard necessarily takes time to obtain a wide ranging understanding and buy-in from the relevant business sectors. Furthermore, it describes the need for long-term ongoing development and support of the TPEG “tooklkit”, which shall be extensible to allow for future needs.

The year 2005 marks the 25th anniversary of the development of the 4:2:2 component DTV standard. This standard – as documented in SMPTE 125, several EBU Recommendations and ITU-R Recommendation 601 – was the first international standard adopted for interfacing equipment directly in the digital domain, avoiding the need to first restore the signal to an analogue format.

This article – one of three published in this edition to celebrate the 25th anniversary of “Rec. 601” – presents an overview of this historic achievement. It provides a history of the standard’s origins, explaining how it came into being, why various parameter values were chosen, the process that led the world community to an agreement, and how the 4:2:2 standard led to today’s digital high-definition production standards.

David Wood interviews pathfinder Peter Rainger (ex-BBC and a former Chairman of the joint EBU-SMPTE Task Force) on his major contribution to the standardization of 4:2:2 digital video, aka ITU Recommendation BT.601

In the late 1970s it was clear that the time was right to standardize the sampling parameters for digital video signals. This would allow the emerging digital “islands” to be connected over the course of time, to form a complete digital programme chain. However, many broadcast engineers preferred composite digital video standards, with the sampling frequency linked to the PAL or NTSC subcarrier, while others looked forward to a universal standard based on sampling separate luminance and colour difference components.

The resolution came from work at BBC Research Department on standards conversion. The BBC became convinced that digital component standards were the way forward and was able to demonstrate how composite signals can be accommodated in a component world – based on line-locked orthogonal sampling patterns.