Verification Central


HDMI 2.1: Channeling the GenX Audio Video Experience

HDMI (High Definition Multimedia Interface), an audio video interface, has been around for quite some time connecting our TVs, computers, video game consoles, Blu-ray players, cable boxes, etc., to deliver top-quality audio video experience.

The arrival of HDMI 2.1 was announced with the promise to deliver faster frame rates, better resolution, greater bandwidth, and a bunch of other noteworthy features. Synopsys recently announced that Novatek has adopted Synopsys’ industry first Verification IP (VIP) and source code Test Suite for HDMI 2.1 and HDCP 2.2 to design their next-generation multimedia chips.

What’s in store?


  1. Higher bandwidth which made a giant leap from 18Gbps (HDMI 2.0) to 48Gbps. Bandwidth is how many bits can be transmitted per second. The doubling of lane rate from 6Gbps to 12Gbps and increasing of data lanes from 3 to 4, raises the effective bandwidth to 48 Gbps (i.e. 18 Gbps * 2 * 4/3).
  2. Higher video resolutions up to 10K at 120Hz. Resolution is the number of pixels in each dimension. Higher resolution means sharper and clearer image.
  3. Faster frame rates up to 120fps. Frame rate is the number of complete still images shown every second. Higher frame rate means more detail and precision, especially for media that changes at high speed like video games or a sports video.
  4. Faster refresh rates allowing 4K, 8K and even 10K video up to 120Hz. Refresh rate is how often a new image appears. Higher refresh rate increases motion resolution and reduces motion blur.
  5. Dynamic HDR (High Dynamic Range), a big improvement. HDR allows to widen the range of both contrast and color, thus increasing the depth in the image and expanding the color levels to provide a more realistic image. The metadata provides the detailed information and is applied just once. Dynamic HDR, with the help of dynamic HDR metadata (carried as a part of Extended Metadata Packets. Yes, HDMI 2.1 has a new packet used to carry large data sets), allows for changes on a scene-by-scene or frame-by-frame basis such that every moment of the video has a different value of depth, detail, brightness, contrast, and color gamut value. Thus every moment can now be realistic!
  6. Game Mode VRR features variable refresh rate, which enables a 3D graphics processor to display the image at the moment. This will result in reduction in both input lag as well as image distortion. So no more torn frames, lag, or stutter!
  7. eARC (enhanced Audio Return Channel), an enhanced form of ARC (Audio Return Channel). ARC allows to send audio from TV to the sound bar or home theatre system via a single HDMI cable, but it passes only Dolby Digital. eARC supports the most advanced audio formats such as object-based audio, and enables advanced audio signal control capabilities including device auto-detect. Thus your sound system can play sounds based on the number and location of speakers in your room.
  8. Display Stream Comparison (DSC) for video that is higher than 8K resolution with 4:2:0 chroma subsampling. Display Stream Compression (DSC) uses a low-latency algorithm to increase resolution and color-depth. DSC allows a maximum compression of 3:1. Thus the bandwidth can effectively increase to 3*48Gbps = 144Gbps.

To learn more about Synopsys VIP and Test Suites, visit

Authored by Meenakshy Ramachandran.