The new DisplayPort 1.4 standard adds support for 8K resolution at 60Hz as well as 4K resolution at 120Hz. For the first time, it also supports HDR (high dynamic range). This is even possible over USB-Type C cables by utilizing a special kind of compression.
DisplayPort 1.4 announced
DisplayPort 1.2 is available in many monitors and PCs today and can drive a 4K display at 60Hz. DisplayPort 1.3, announced one and a half year ago and only available in a few consumer products today, added support for 5K at 60Hz and 8K at 30Hz.
The new DisplayPort 1.4 standard is capable of driving even more demanding signals such as “8Kp60Hz deep color” and “4Kp120Hz deep color”. However, the biggest news here is probably support for HDR (high dynamic range).
DisplayPort 1.4 has the same 32.4 Gbps transfer rate as DisplayPort 1.3 but the company is using a new “Display Stream Compression” (DSC) technology that it claims can transfer “visually lossless” video with up to 3:1 compression ratio. That “visually lossless” claim certainly sounds questionable but the VESA group says that it has done extensive testing.
The dedicated DisplayPort connector will continue to exist but more importantly all of the capabilities and features of DisplayPort 1.4 can be integrated into the USB Type-C port and Thunderbolt connectors, meaning that you will soon be able to transmit 8K and HDR signals over a standard USB Type-C interface.
Positioning it as a TV interface
Traditionally HDMI has been considered a standard for AV/TV, whereas DisplayPort has mostly been used in PCs. The VESA group, which is developing DisplayPort, wants to change that perception and make DisplayPort relevant also in the AV/TV segment.
- “This significant update to the DisplayPort standard is vital to continued growth of adoption for both DP and DSC, particularly in such fast-growing markets as digital television and automotive infotainment,” said VESA Board Chair Alan Kobayashi. “New applications are demanding displays with better resolution, wider color gamut, and increased dynamic range.”
The group is trying to make DisplayPort relevant to TVs through support for 4K and 8K but more importantly through support for HDR (high dynamic range). The 1.4 standard supports HDR metadata that is used to signal to HDR-capable TVs that a HDR signal is sent. The group says that it uses a flexible metadata solution that will also support “future dynamic HDR standards”. The HDMI 2.0a standard already supports HDR but besides that it is far less capable than DisplayPort. DisplayPort 1.4 even includes “DP to HDMI 2.0a protocol conversion”.
VESA says that DisplayPort 1.4 also has support for “32 audio channels, 1536kHz sample rate, and inclusion of all known audio formats” to match HDMI’s capabilities in the audio segment.
It is not clear when we can expect to see the first products with DisplayPort 1.4. DisplayPort 1.3 was announced one and a half year ago and has yet to make inroads into the market.
So, will the 1.4 finally make the DisplayPort standard relevant in the TV market? It certainly has potential.
Forward Error Correction – FEC, which overlays the DSC 1.2 transport, addresses the transport error resiliency needed for compressed video transport to external displays.
HDR meta transport – HDR meta transport uses the “secondary data packet” transport inherent in the DisplayPort standard to provide support for the current CTA 861.3 standard, which is useful for DP to HDMI 2.0a protocol conversion, among other examples. It also offers a flexible metadata packet transport to support future dynamic HDR standards.
Expanded audio transport – This spec extension covers capabilities such as 32 audio channels, 1536kHz sample rate, and inclusion of all known audio formats.