Sep 102014

REVO DAB radioThis was the first DAB radio to be launched by REVO. Designed to be retrofitted to cars the radio itself was removable and was a comfortable pocket size to be carried between cars. Although wiring harnesses were available to connect audio accessories to many cars they were problematic, often with expensive installation costs. At the time, the low power FM transmitters used for this purpose today were still unlicensed so along with an internal DAB aerial, we proposed and designed an active, FM modulator and low noise RF isolator. This allowed the signal from the DAB radio to be received as an extra station along with those received from the existing FM aerial.

Launched in the early years of DAB it won numerous awards and was very well received by both the audio and automotive press.

Westwood Rock - engineering your success

Sep 102014

Infusion pumpA complete electronic subsystem was developed for the control of a disposable infusion pump for applications such as analgesia. The device used an LCD screen and stored dose records in a non-volatile memory.

Challenges included low power battery management, DC motor control, safety interlocks, fault mitigation, and cost sensitive design.



Westwood Rock - engineering your success

Sep 102014

Solid State power control demonstrator for Passenger Airliners Traditional power control systems were electromechanical and solid state solutions promised significant weight and size reductions. The client came to us having supervised a previous prototype layout which had failed due to EMC problems within the PCB. We were engaged to produce a new circuit layout to the client’s specification paying particular attention to EMC radiation from the power circuits, and the susceptibility of the control signals.

Challenges included high voltage switching in close proximity to the small signal control circuitry. The solution had to meet sometimes conflicting requirements of safety, EMC and fast low loss switching.

The new circuit and layout worked as intended.

Achievement: Resolved a problem that enabled the client to demonstrate their first solid state power controller for passenger aircraft.

Westwood Rock - engineering your success

Sep 102014

Field scanner laserThe field scanner was used for counterfeit protection. It produced a digital signature for real objects based on a laser scan of their surface texture. The brief was to take a prototype to a pre-production model. The unit was to be powered from USB,. It was to use DC motors positioned using PWM drive from a PID control loop rather than stepper motors. The board outline was to be changed and significant cost reductions were required.

Challenges included USB power management, a dramatic cost reduction, the use of optical sensors with high precision ADC conversion and the team pre-empted the obsolescence of parts “not recommended for new designs”.

Achievement: All the requirements were met with a build cost reduction of 75%.



Westwood Rock - engineering your success

Sep 102014

Video Laryngoscope The Video Laryngoscope is a medical device. It is a hand-held endoscopic instrument used during laryngoscopy and endotracheal intubation.

Traditionally direct laryngoscopy involved using a device to move the tongue out of the way to allow the larynx to be viewed directly; sometimes incorporating a light source. The Video Laryngoscope relays an image from a sensor at the tip of the blade to a screen to the LCD viewer. It also provides a video output for display on a large screen, recording or for training purposes.

When the Laryngoscope was designed, the sensor used was the smallest of its kind in the world. Despite the quality of the sensor significant signal processing was required to control the image exposure and colour balance as the usual automatic algorithms for cameras tend to fall down when the image is predominantly one colour.

One of the challenges was the power management. It can be used as a traditional, stand-alone laryngoscope, with the LED in the tip powered from a conventional AA battery inside the handle. If the Video Viewer is mounted on the handle the Lithium rechargeable battery in the viewer takes over, powering both the viewer and the illuminating LED in the blade tip. The high image quality camera chip and high intensity white LED light source provide a clear image of the laryngeal structures.

Achievement: A complete electronic design and camera module design, incorporating power management, video signal processing and user interface.

The Venner AP Advance Video Laryngoscope was the winner of the 2011 Red Dot Design Award in the field of life sciences and medicine.
“The jury have returned a verdict that the Venner A.P. Advance is an outstanding piece of equipment right up to and including its finest details. A medical tool which is simple to understand, the video laryngoscope uses the benefits of modern technology, and also combines selected materials. This makes the Venner A.P. Advance a device which not only meets the demands of patients and medical staff, it also exceeds them.” [1]

[1] For red dot winners, product design, Subject: life science and medicine, See


Westwood Rock - engineering your success



Sep 102014

Electroencephalograph subsystem - Evaluation board for EEG and Processor

Evaluation boards for EEG and Processor

Part of a larger more complex medical product the electroencephalograph subsystem used a 24 bit 8 channel ADC with integrated ECG/EEG front end. The applications support for this device was almost exclusively for electrocardiograph designs rather than the more sensitive electroencephalograph required for this development. The EEG demonstrator incorporated signal processing in software to compensate for temperature drift and to reject mains pickup which is the dominant noise source in biosensors of this type.


Electroencephalograph subsystem -Test Waveforms on touchscreen LCD demonstration

Test Waveforms on touchscreen LCD demonstration

Achievement: A fully functional subsystem was demonstrated using evaluation boards reducing the development risk dramatically and custom PCBs were then developed and integrated into the product.





Westwood Rock - engineering your success

Sep 102014

Broadcast Archive Quality AssuranceThis system was a bespoke development for a National Broadcaster. The Quality assurance of material that is being transferred from different types of media to digital storage for archival purposes is very time consuming and expensive. When problems are missed it can be years before the problem is discovered and the originals may have been lost.

Challenges included interfacing with both the now obsolete tape machines and the digital work stations as well as automating the validation process.

Achievements included integrating test sequences developed by the client to check the tape machines that were being used to play the material to be transferred.



Westwood Rock - engineering your success

Sep 102014

Fibre optic link for Outside Broadcast camerasThe electronics team have considerable experience from working in the broadcast television industry, designing equipment that has been used by the majority of the world’s national broadcasters including amongst others the BBC and ITV in the UK, PBS in the USA. For example they have worked on digital video effects machines, one of the first digital serial video signal routers and the ETSI codec used to link television studios with digitally compressed video, audio and data.

Because broadcast signals pass through multiple processes and links between the cameras and the viewer’s television sets any degradation accumulates so the team are used to working to very accurate colourimetry.

When shooting a drama on location or a live broadcast from a concert hall, race track or Grand Prix a host of signals have to be passed to and from the camera. These include high quality program video and audio, viewfinder video and headphone audio for the cameraman to monitor, remote control of camera functions and a three way intercom between the camera man and both engineering and production staff.

Our first design was the earliest aftermarket camera link to use digital modulation of the light on the fibre, previous systems had used analogue modulation. Now all similar systems use digital modulation.

This was a power efficient design to maximise battery life when powered from industry standard rechargeable batteries. It included safety interlocks to protect operators when high voltages are supplied via the cable.

A ground breaking product followed by many others in the same field, including a number of patents.

Westwood Rock - engineering your success

Sep 102014

Military and Security CommunicationsThis project was a communications system for military and security markets. The military, coastguard and security services around the world are making increasing use of Commercial Off The Shelf (COTS) equipment, where it is available and meets the operational and environmental requirements. In this case available equipment did not meet all our clients’ requirements, and the application did not need secure procedures for its development. The environmental specifications were challenging, but we were able to develop a bespoke architecture, custom circuit boards, firmware and software, using “off the shelf” semiconductors and materials.

Challenges included the combination of extreme environmental specifications and a cost sensitive market.

Achievements were summed up by the client’s observation that the main selling point was not the feature set that they had foreseen and specified but the flexibility of the system to implement those that they had not foreseen.

Westwood Rock - engineering your success

Sep 102014

Video compression - DiracIn 2009, Westwood Rock announced that it was releasing the first of a series of video codec cores compliant with the BBC-developed Dirac Pro compression system [SMPTE ST 2042]. Westwood Rock’s VC-2 Dirac core set provides a rapid and cost effective method for deploying VC-2 Dirac compression.

Shipping in equipment since 2015


A Background to VC-2 Dirac

In 2002, the BBC identified a set of video codec requirements that it recognised as important for both a quality broadcast infrastructure and for video film production. Despite there being a wide range of compression systems and equipment on the market, the BBC was unable to source a system that addressed all its requirements.

The problem was significant enough for the BBC to embark on a programme at its internationally-respected Kingswood Warren Research Department to conceive a compression system that fulfilled all of its requirements for quality broadcasting and film production. The outcome of this extensive R&D is the compression system known as Dirac.

As the BBC is a public broadcaster, it chose that the Dirac specification should be an open technology, free from royalties. The BBC is a world-renowned broadcaster and video film originator of high quality productions. In Dirac they had designed a complementary quality compression system which is very practical, flexible and elegant.

Westwood Rock

The engineers at Westwood Rock had been designing video hardware and core IP for over 20 years. Besides the prevalence of Westwood Rock’s designs in the broadcast and film industries, they had also taken their video expertise into aircraft, medical imaging, industrial vision and surveillance. Westwood Rock has extensive experience of FPGA design and works closely with all the major FPGA vendors. Additionally, the team includes some of the most respected ASIC designers in the industry.

The development of this exciting set of cores was a natural fit for Westwood Rock’s skillset and expertise.

The VC-2 Dirac Core Set

Small Form Factor

The core is the smallest video codec available and has been designed to fit into FPGA vendors’ cost-effective families.


A small form factor has not resulted in a reduction in quality. As you would expect of the BBC, quality has been key to the development of Dirac technology. The main profile implementation of VC-2 Dirac Pro rivals JPEG2000 and yet has a latency as low as a single frame and a very hardware-efficient form factor.

Low Delay – only a few lines of latency

Uniquely, in the low latency profile a compression factor of 8 times can be achieved with only a few lines of delay. This means that multistandard HD-SDI (1.5Gbit/s) can comfortably be carried over an SDI (270Mbit/s) link. Alternatively, 3Gbit/s HD-SDI can be compressed to a 1.5Gbit/s HD-SDI link with very little delay and, again, in a small hardware form factor. Of course this means that signals such as 1080P60, stereoscopic 3D production, Digital Cinema or other new formats can be transported over an existing studio infrastructure.

Visible picture information over a compressed link:

Yet another unique feature is that a real time low-level picture is visible on a standard monitor over the ‘compressed’ SDI link.

Low power, low cost

The small hardware form factor means that the power consumption of the hardware is lower and, as fewer logic cells are used, the cores can fit into smaller FPGAs. The pricing structure is competitive at all volumes and particular attention has been given to allowing low quantity usage access to the technology. At the high volume end of the market, the core will be available for ASIC designs with Westwood Rock able to offer a full turnkey solution.

VC-2 Dirac Pro over SDI, ASI and IP plus open source software

As already stated, the Dirac Pro core set will provide transport over SDI, but it can also be used over ASI and IP links. An open source software codec is available, as are over 6000 conformance test sequences


All the above is covered by SMPTE and relevant standards. Westwood Rock fully supports the BBC’s philosophy of making Dirac an open standard.

High compression

Initial core releases concentrate on the low delay and main profiles. Later Westwood Rock intends to release long GOP Dirac cores that will yield considerably higher compression ratios. In comparison, the long GOP Dirac core will be a simpler alternative to H.264 and X.264, suitable for video distribution and mobile applications.

Flexibility – any picture format

The VC-2 Dirac compression system and core set is not locked to a given picture format as it is wavelet based, which makes it very flexible. This means that VC-2 Dirac can compress pictures from a QCIF format right through to UHDTV, and also has customisable picture formatting to accommodate any new picture standards. Parameters such as frame rate, chroma subsampling and bit depth are flexible. Scan formats can be progressive or interlaced.

Design Services

As an established design consultancy with a great deal of experience in broadcast, communications and FPGA/ASIC design, Westwood Rock will be able to support end users of the core from concept through to finished system design or final silicon. Westwood Rock’s codec experience is extensive and includes contribution quality codec design, digital cinema and set-top box design. Reference designs will be made available as cores are released.

Westwood Rock is able to offer support in both hardware and software design.

In summary…

The BBC has designed Dirac so that it provides flexible, high quality, low latency, low form factor compression.

The BBC developed Dirac to be a truly standardised, non proprietary, royalty free and open technology.

Dirac has been developed by the BBC for its own use, concentrating on the broadcast chain and video film production.

The emphasis on high picture quality, low delay and low hardware complexity makes Dirac compression suitable for a wide range of imaging applications.

Westwood Rock is excited about this technology and will champion ease and breadth of access to the full set of VC-2 Dirac cores for all interested companies, using a pricing structure that encourages adoption of Dirac regardless of usage volume.


Westwood Rock - engineering your success