HS8K HDMI Cables: Video Formats, Color Depth and DSC Explained
Video Formats, Color Depth and compression.
Read the complete Video Format.
“8K at 60 Hz” describes resolution and refresh rate. It does not tell you the Pixel Encoding, Color Depth or whether Compressed Video Transport is used. Those details matter when matching a source, a display and an HDMI cable.
This guide covers selected 4K and 8K video modes for Cruxtec HS8K active optical HDMI cables in 10, 15, 20, 30 and 50 metre lengths.
How to read a Video Format
Pixel Encoding
This describes how pixels are represented for transmission. RGB and YCbCr 4:4:4 retain full colour sampling. YCbCr 4:2:2 and 4:2:0 use chroma subsampling, reducing colour information relative to brightness information.
Color Depth (bpc)
Bits per component (bpc) specifies the number of bits for each R, G and B component, or each Y, Cb and Cr component. The tables list 8, 10 and 12 bpc.
The Source sends the HDMI audio/video stream. The Sink receives it, for example the display in a direct connection.
4K resolution table
60 and 120 Hz modes in RGB or YCbCr 4:4:4.
Scroll the table horizontally to view every column.
| Refresh rate |
Pixel Encoding | Color Depth bpc |
Video transport | Equipment requirements |
|---|---|---|---|---|
| 60 Hz | RGB / YCbCr 4:4:4 | 8 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. |
| RGB / YCbCr 4:4:4 | 10 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. | |
| RGB / YCbCr 4:4:4 | 12 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. | |
| 120 Hz | RGB / YCbCr 4:4:4 | 8 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. |
| RGB / YCbCr 4:4:4 | 10 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. | |
| RGB / YCbCr 4:4:4 | 12 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. |
8K resolution table
Selected 24, 30, 50 and 60 Hz modes. Read the Pixel Encoding and Color Depth together.
Scroll the table horizontally to view every column.
| Refresh rate |
Pixel Encoding | Color Depth bpc |
Video transport | Equipment requirements |
|---|---|---|---|---|
| 24 Hz | RGB / YCbCr 4:4:4 | 8 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. |
| RGB / YCbCr 4:4:4 | 10 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. | |
| RGB / YCbCr 4:4:4 | 12 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. | |
| 30 Hz | RGB / YCbCr 4:4:4 | 8 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. |
| RGB / YCbCr 4:4:4 | 10 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. | |
| YCbCr 4:2:2 | 8 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. | |
| YCbCr 4:2:2 | 10 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. | |
| YCbCr 4:2:2 | 12 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. | |
| YCbCr 4:2:0 | 8 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. | |
| YCbCr 4:2:0 | 10 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. | |
| YCbCr 4:2:0 | 12 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. | |
| 50 Hz | YCbCr 4:2:2 | 10 bpc | Compressed Video Transport | VESA DSC 1.2a over FRL; the Source and Sink must support this mode. |
| YCbCr 4:2:0 | 8 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. | |
| YCbCr 4:2:0 | 10 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. | |
| YCbCr 4:2:0 | 12 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. | |
| 60 Hz | YCbCr 4:2:2 | 10 bpc | Compressed Video Transport | VESA DSC 1.2a over FRL; the Source and Sink must support this mode. |
| YCbCr 4:2:0 | 8 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. | |
| YCbCr 4:2:0 | 10 bpc | Uncompressed Video Transmission | The Source and Sink must support this complete Video Format. |
About the 48Gbps rating. This is the cable’s manufacturer-rated link capacity, not the usable video data rate. HDMI transmission includes encoding and other overheads. A resolution and refresh rate alone do not establish the required link configuration.
Modes not listed. Their absence is not a statement that HDMI cannot carry them. Check the complete mode against the cable and equipment specifications.
What FRL and DSC change
- FRL
- Fixed Rate Link is the HDMI signalling method used for higher video data rates. A 48Gbps cable rating does not establish the FRL capability of the connected ports.
- E-EDID
- Enhanced Extended Display Identification Data communicates the Sink’s capabilities to the Source, helping it select a compatible Video Format.
- DSC
- Display Stream Compression reduces video data for transmission. VESA describes it as visually lossless. Compressed Video Transport in the HDMI Specification Version 2.1 uses VESA DSC 1.2a over FRL. The Source and Sink must support the relevant compressed format; the cable itself does not switch compression on.
Check the source and display specifications together. Matching the resolution alone is not enough: refresh rate, Pixel Encoding, Color Depth and DSC support must also agree.
Find your HS8K cable length
The listed modes apply to the five HS8K models below.
For the optical transmission principle, read how active optical cables carry display signals. For cable naming, see why HDMI cable names do not use version numbers.
Sources and further reading
- HS8K manufacturer’s colour-mode and resolution reference table, supplied to Cruxtec. Source for the listed product modes and length coverage.
- HDMI Licensing Administrator: video formats, colour depth and compression. General 48Gbps transmission reference; not a product certification record.
- HDMI Licensing Administrator: FRL and DSC terminology. The current specification includes capabilities beyond this 48Gbps product range.
- VESA: Display Stream Compression.
All HDMI trademarks and trade dress are registered trademarks or trademarks of HDMI Licensing Administrator, Inc.
