PowerVR Video: ready for the prosumer camera boomThe article in the blog of Francisco Socal (Francisco Socal, https://imgtec.com/blog/author/franciscosocal/)
Francisco Socal, London, UK, 17th October, 2016 – Over the last few years the digital camera market has come under increasing attack from the smartphone. As each year sees an increase in quality of the standard smartphone camera so the consumers’ need for a compact camera declines. And the pressure is relentless; with the appearance of dual cameras on newer phones, which offer higher quality, and the ability to use as an optical zoom, the few remaining features that gave pocket cameras their unique selling points are eroding. The smartphone has lowered the barrier to publish and distribute video – with self-promotion on YouTube and broadcasting live to the world on Facebook the new norms.
What this has done is to create a split in the market. As the need for lower-end compact cameras has declined, so consumers have moved higher up the food chain to so called ‘prosumer’ cameras – to DSLRs and to compact system cameras. .As the quality of these cameras has continued to increase, they are becoming attractive entry-level options the professional market, creating a growing ‘prosumer’ tier.
Additionally, entirely new segments of camera are becoming increasingly significant, such as action and dash cams, drones and VR – all prime markets for 360° video. This report from ABI Research points towards two million pro and prosumer level 360° image products shipping by 2021.
At all levels of the market, there is an increasing expectation from consumers for image quality. This is fuelled by the rise of Ultra HD 4K formats, which along with increased resolution are also looking to enhance motion fluidity by increasing frame rates from the standard 24 and 50fps to 60 and even 100fps and beyond. And even as we move to 4K, we’re seeing Japanese broadcasters NHK readying Super Hi-Vision 8K images for the 2020 Olympic Games in Tokyo.
Meanwhile, High Dynamic Range (HDR), with its emphasis on increased colour range and contrast performance, is proving to have an even more visceral impact on perceived image quality than the resolution bump that 4K brings over Full HD 1080p.
The challenge for equipment makers then is to offer these high-level capabilities in as efficient a package as possible. Quality needs to be maintained without compromises in terms of battery life or manufacturing cost.
The volumes and average selling prices of these products can justify investments into producing dedicated SoCs to give efficient implementations. These designs enable manufacturers to achieve the quality they need and differentiate from mainstream “me too” off-the-shelf application specific standard product (ASSPs).
This is where Imagination Technologies latest PowerVR video cores excel. The PowerVR E5810 Encoder and the PowerVR D55200 Decoder are the latest additions to Imagination’s portfolio and are designed to specifically target prosumer and professional video applications.
These IP cores have been designed from the outset to deliver the high quality expected by the industry in a small silicon footprint.
Unlike some competitors, the PowerVR E5810 Encoder video core support 4:2:2 Chroma subsampling and 10-bit colour. This is crucial, as it ensures that quality levels are maintained as you move down the production chain. Consumer level kit typically uses 4:2:0, which invariably results in artefacts. These include colour bleeding, and a loss of chroma detail. 8-bit colour will typically cause banding issues across large areas of colour such as blue skies or sunsets and 10-bit colour reduces these as well as other artefacts such as contouring and smearing. 10-bit colour can also deliver increased codec efficiency and so provides an optimal balance between colour reproduction and bandwidth.
While codecs such as H.264 and VP8 have been the mainstay for the last few years, the industry is moving to the more processing intensive High Efficiency Video Coding (HEVC), also known as H.265, to provide higher quality with minimal bandwidth requirements. The PowerVR E5810 Encoder supports HEVC/H.265 encoding up to 4K/60 and enables video stream compliance with ITU-R rec BT.2020, the revised colour space for Ultra High Definition TV. While, VP9 has gained some traction in consumer markets, especially promoted by Google for YouTube, outside of this it is not generally viewed as a key contribution format.
Architecturally, the PowerVR E5810 Encoder and PowerVR D55200 Decoder introduce exciting new features to create an efficient system architecture, making them ideal for tackling the demands of the new camera form factors.
First of these is direct connectivity between the IP cores, which negates having to rely on external memory. This significantly reduces external memory bandwidth reducing power consumption.
The new cores also provide ultra-low latency options – essential for wireless video transmission and remote operation. They also support the processing of multiple simultaneous streams, needed for 360° video cameras.
The PowerVR E5810 Encoder can also target different resolutions and formats simultaneously, a requirement for applications such as drones with local storage, remote live preview and monitoring. For example: the primary content may be recorded in cinema 4K 1-bit at 24 frames per second 4:2:2, while a secondary 720P at 24 frames per second 8-bit 4:2:0 is streamed over a wireless link to the remote camera operator. The multi-stream capability and input scaler included with the PowerVR E5810 make this easy to achieve with just a single encoder core.
For the prosumer camera market the rate control features means that the PowerVR E5810 Encoder can offer a Streaming Variable Bitrate (SVBR), also known as Peak Constrained VBR. This means that when recording to flash memory the bitrate in a camera can be guaranteed, without any fear of a buffer underflow, while enabling the bitrate to be reduced below the specified bitrate when the content is simple and does not require higher bit-rates.
Backed by a mature and extensive software stack, Imagination’s Video IP lends itself well to any SoC image manufacturer looking for a fast route to market with a well-established solution. The PowerVR E5810 Encoder and PowerVR D55200 Decoder chips are already licensed and immediately available for new licensing, bringing new levels of quality and performance to the ever-growing prosumer camera and wider imaging market.