From A for AGF Videoforschung to Z for zapping, the most important technical terms in video research are explained here.

DAP GmbH is an IT service provider in the field of market and media research, which has been engaged by AGF to develop evaluation software for the AGF data. The AGF offering of software programmes comprises VIDEOSCOPE, VIDEOSCOPE PLUS, TV CONTROL, PLAN TV and WEBCROSS.

The data rate refers to the number of bits transmitted per unit of time and is decisive for the transmission quality of TV images. It is stated in megabits per second (MBit/s).

The fact “Deliveries” is sub-divided into “Content Deliveries” and “Advertising Deliveries.” It indicates the gross number of call-ups a programme or ad spot in an offering unit.

In line with the company’s hybrid approach, streaming measurement is performed both in the census measurement and in the Desktop Panel. This data includes structural information on persons (e.g. age, sex). The census and panel measurements are aligned in the calibration process (usage level adjustment). The Desktop Panel is composed of around 15,000 active panelists who allow their video-streaming usage to be measured via their private/personal PCs or notebooks/laptops.

Digital receivers are auxiliary devices or modules integrated directly with the TV set for the reception of television and digitally broadcast radio programmes. Depending on the equipment, digital receivers can also receive other digital services.

Digital television refers to the digital transmission of TV programmes. In digital transmission, conventional (analog) video and audio are converted into a binary code (0s and 1s). Unlike analog transmission, however, not every individual picture is transmitted in full, but only the part that actually changes from frame to frame. Thanks to the method of data compression (e.g. mpeg), more digital than analog programmes can be transmitted at each frequency. A digital receiver is needed to receive digital video and audio signals.

DVB-C is the standard for the transmission of digital broadcasting signals via cable.

DVB-S is the standard for the transmission of digital broadcasting signals via satellite.

DVB-T is the standard for the transmission of digital terrestrial television signals.

The digitization is a key figure for measuring the digitization of TV reception in Germany. It indicates the percentage of households that receive their TV programming via digital transmission technologies such as digital cable or IPTV.

DSL is an acronym that stands for Digital Subscriber Line. It refers to a transmission standard under which data can be transmitted and received at high transmission rates via a bifilar copper line of the telephone network. Because DSL data is transmitted in a different frequency range than telephone data (voice or fax), users can speak on the telephone and surf the Internet at the same time. A DSL connection offers much faster Internet speeds than earlier modem and ISDN connections.

The dual-frame-method describes the telephone, randomly controlled sampling using a combination of landline and mobile phone numbers. As a result, those people who can be reached primarily or only by mobile (mobile onlys) are also included in the sample. In the case of dual frames, the sample is drawn from two frames or selection frames that completely cover the population: fixed network plus mobile. A suitable design weighting is then necessary to combine the two samples.

The duration indicates the average viewing duration of the users of a programme. It only includes the persons who actually watched TV.

DVB is an acronym that stands for Digital Video Broadcasting. It refers to the international transmission standard for digital television. Under this standard, digital broadcasting signals are transmitted by way of data compression (see mpeg). The suffixes C, S, and T indicate the transmission channel for the signals, i.e. cable, satellite or terrestrial. In Germany, the development of DVB-H – which enables the transmission of digital television to mobile terminal devices such as smartphones – is currently not being further pursued. The suffixes S2, C2 and T2 describe the standard for high-resolution television.

DVR is an acronym that stands for Digital Video Recorder. It refers to a recording device that contains a hard drive for recording programs. Users can begin playing a program even while it is being recorded. This is referred to as time shift.