AptoVision’s new Plethora is a fully in-line engine for high fidelity processing of uncompressed audio and video signals. Available on its BlueRiver NT+ and BlueRiver 400 chipsets, the Plethora Engine is appropriately named for the numerous functions it integrates into a single, in-line, zero-frame latency signal processing subsystem. These functions include broadcast quality scaling, visually “indistinguishable” light-compression, multi-source video compositing, video splitting, color space conversion, frame rate conversion, audio embedding/de-embedding, audio down-mixing and audio re-sampling. The Plethora engine is fully embedded into and tightly coupled with the BlueRiver chipset’s signal extension and switching capabilities delivering the world’s first and only single-chip solution for end-to-end signal distribution and processing.
Broadcast Quality Scaling
Optimized for video, graphics and text quality, the Plethora engine supports both up-scaling and downscaling for resolutions up to True 4K/60/4:4:4. This broadcast quality scaling engine is architected with fully programmable horizontal and vertical taps and includes pre and post processing algorithms to reduce ringing and aliasing artifacts while preserving the sharpness of edges. The scaling engine operates in-line with the other functional blocks of the chipset such as HDMI encoding/decoding, AES 128-bit encryption, extension (10G streaming), light compression (if and when needed) and only adds 16-lines of latency to the video transmission (or just ~30us of latency at 4K/60Hz). A wide variety of formats including RGB and YUV (444/422/420) are supported along with 8, 10 and 12 bit color depths.
Support for in-line scaling enables AptoVision BlueRiver extension and switching chipsets to deliver on the following commonly used Pro-AV Applications:
Display adaptive scaling in 1×n signal distribution: When a source is being transmitted to multiple displays of varying resolutions, the scaling engine in each receiver can automatically upscale or downscale the source to the native resolution of the attached display if and when needed, ensuring that each display receives the source in its optimal image quality. Without this capability, the source would have to be set to the resolution of the lowest resolution display forcing all higher resolutions display to always show a lower quality up-scaled image.
True seamless switching in n×m signal distribution: In a Matrix switching environment, switching a display from one source to another typically results in a black screen, frozen frames or other artifacts. With Plethora’s scaling engine integrated into an AV over IP platform, truly seamless switching can be achieved where the switching delay is only 1-2 frames and without any artifacts, irrespective of the resolution of the switched source.
Multi-view, PIP, and PAP: The scaling engine works hand in hand with the multi-source video compositing capabilities of the Plethora Engine to deliver multi-view, picture-in-picture (PIP) and picture and picture capabilities (PAP) within the AV signal distribution system and without the need for any additional equipment.
Video wall processing: When used with the video-splitting and bezel correction capabilities of the Plethora Engine, the scaling engine also enables full video-wall capabilities without the need for additional equipment.
Pixel Perfect Light Compression
AptoVision’s extension and switching chipsets transmit uncompressed, pixel for pixel video signals extended over long distances and switched through IP switches with zero-frame latency. In very few cases, it may be desirable to apply light compression to enable a video resolution to be transmitted across a limited bandwidth network or to enable longer distance transmission for the same resolution. For such cases, AptoVision has developed a unique new compression algorithm with a compression ratio of just 1.4:1 to enable pixel-perfect image quality. When enabled, this ultra-low compression ratio results in mathematically lossless compression for most content and visually indistinguishable image quality for the remaining cases. What’s more, the compression codec functions in-line with the rest of the various AV processing and adds only 7-lines on latency (<15us for 4K/60Hz).
Multi-Source Video Compositing
The Plethora engine’s multi-source video compositing capability allows each BlueRiver receiver to combine multiple video sources onto a single display enabling a variety of applications such as multi-viewer, picture-in-picture and picture-and-picture. This multi-source video compositing capability is tightly coupled with the scaling engine which is used to scale the resolution of each source to the target window on the display canvas. This 4K/60 capable compositing engine can tolerate a large number of asynchronous inputs and can render without tearing or other visual artifacts. Multiple presets are available and layouts can be updated in real-time.
Video Splitting and Bezel Correction
The Plethora engine’s multi-source video compositing capability also allows each BlueRiver receiver to automatically split an incoming video and render only a portion of the image as part of a video wall. Configurable bezel correction support compensates for the thickness of the bezel to virtually hide the pixels needing to be obscured by the display bezel. Combined with the scaling engine, this capability delivers video walls of any size and eliminates the need for additional equipment.
Pro-AV applications often require the flexibility of supporting many types of input formats e.g. RGB, YUV 4:2:0, YUV 4:2:2. Mismatches between the format being output by the source and the formats supported by the display are common, resulting in interoperability issues. The Plethora engine integrates an in line color space converter which automatically converts between mismatching color spaces between the source and the display. For example content sourced as YUV can be converted to RGB for easy compatibility with DVI displays. Perhaps more importantly, in our 4K world, it means full capabilities for chroma subsampling conversion. For example, content at 4K60 4:4:4 can be downsampled to 4K60 4:2:0 for supporting first-generation 4K60 displays.
Interoperability of resolutions and color-spaces is incomplete without the ability convert frame-rates as mismatches in resolutions and colorspaces are also often accompanied by a mismatch in frame-rates. The Plethora engine includes full arbitrary frame rate conversion, enabling true cross-conversion from any resolution and frame-rate to another. For example, 4K30 can be scaled down to 1080p60. 1080p24 can be scaled up to 4K60. Content sourced at 59.97 Hz can be used along with 60 Hz content without any special considerations. Other AV processing capabilities of Plethora, such as scaling and true seamless switching also benefit from frame-rate convers – a monitor will never have to re-sync during an input switch, regardless of the associated resolution or refresh rate.
Highly flexible audio capabilities
Professional AV applications often have audio requirements as complex as their video requirements, and the Plethora Engine delivers on all of them.
Sample rate conversion: To support seamless switching, or simply to match the capabilities of a low-cost audio system, the Plethora engine can convert the sample rate of any PCM stream (stereo or multichannel) to any other.
Stereo down-mixing: A large matrix video system may include destinations with varying audio capabilities. A home theater is built for high resolution multi-channel audio, but the small television in the kitchen may only accept stereo audio. By enabling each endpoint to down-mix multi-channel PCM to stereo PCM (and in combination with sample rate conversion), compatibility with any audio destination can be guaranteed.
Audio embedding and de-embedding: Sometimes even the audio processing built into the Plethora Engine isn’t enough, like when the AV switching system needs to be integrated with a full blown audio DSP for mixing program audio and sound reinforcement. To enable this, the Plethora Engine allows audio to be extracted from an HDMI feed and output via I2S to other on-board modules, such as DSPs, DACs, or popular networked audio modules and gear. After processing, this audio can be re-embedded with video, and sent via HDMI stream or a BlueRiverNT+ AV network feed. Analog audio may also be embedded by connecting an ADC to the I2S input port on the Plethora Engine.