USB-based Peoplemeter Devices

The need for Peoplemeters...
Increasing numbers of channels, multiple broadcasting platforms, increased number of TV sets and remote controls per family have lead to a complex TV environment. AGB Lab's TVM peoplemeters are installed on every TV set in the panel** home. Each meter is capable of accurately monitoring, at every and any moment, what is being viewed on each TV set, by whom, and of storing this data. The meter then transmits all the stored data to a Production Center, by means of a telephone line or a dedicated cellular (analog and GSM) telephone line.

** The panel is a statistical sample of the universe to be measured and refers to the group of homes, which accept the installation of the peoplemeter on all the TV sets in their home.

AGB Lab's TVM5
TVM5 consists of a Base Unit, Display Unit and Transmission Unit. The Base Unit and Display Unit serve as the user interface. The Transmission Unit collects data from all the Base Units in the household using ***SRD wireless communication and establishes a connection with the computer center via a landline or GSM/GPRS modem using a direct or internet connection. Time shifted viewing (viewing from pre-recorded VCR tape) is also processed on the Transmission Unit. All Base Units and Transmission Units include a USB port used to configure and monitor the units running set up software on the personal computer.

***SRD = Short-range radio devices

Each time a TVM5 unit is installed in the field, it must be configured. AGB Lab's technicians use a Windows based application to set up the unit and verify its functionality. Part of this set-up procedure requires transfer of large amounts of data from the unit to the PC (video image capturing), or fast and reliable data transfers (system logging). TVM5 uses USB as the main communication port between the unit and the setup software running on the PC. AGB Lab chose to implement a USB interface in the 5th generation product due to the prevalence of USB on PCs as well as the fact that it is a fast, reliable and uses a very defined protocol.

A detailed look at AGB Lab's TVM5
AGB Lab's TVM5 contains features to measure all known TV platforms and devices, can easily detect the source and broadcaster of a TV picture without any reference needed at the calling center. It is not just a measuring system but also actively simplifies the multiple video connections to a TV and acts as an active A/V switch.

TVM5 design is based on a non-intrusive concept, emphasizing high reliability, resistance to panel member tampering, easy installation, and full off-site remote control including remote on-line checks, configuration and programming. This is achieved using latest technologies and measuring principles and has sufficient redundancy to facilitate any future modifications or extensions. The powerful DSP controller core, controlling all TV environment formats and combinations available, enables the system to recognise and measure any theoretically known detection method routine.

TVM5 detection is able to digitize any video signal and then create a digital picture into its own memory. This digital image is mainly to read the banner content of any decoder/receiver box using an OCR technology.

USB Driver Development on Windows
AGB Lab engineers noted that utilizing the USB port on Windows platforms requires an extensive knowledge of the USB protocol as well as knowledge of Windows based driver programming. AGB Lab specializes in data acquisition hardware, signal processing software and hardware, video image analysis (OCR, etc.) and measurement technology. Developing a USB driver with the DDK would mean diverting resources from their main task, thereby delaying time to market and increasing development costs.

AGB engineers searched for a tool that would provide a performance-optimized API for their specific USB-based hardware. AGB Lab did market research, trying out different tools available on the market. They explained that their selection of WinDriver was a rational decision based on tests that revealed:

• WinDriver provided an API specific for their driver
• They didn't have to study the DDK nor the USB protocol details, and WinDriver promised to save time (and therefore money).
• The documentation was very well written, examples are clear.
• The WinDriver API was easy to use