Summary of DisplayHDR Specs under CTS 1.1
Information about the CTS 1.2 specifications announced May 7, 2024 may be found here.
The table below is a summary of the specifications for the VESA DisplayHDR and DisplayHDR True Black standards as they are updated by CTS 1.1 released on September 4th, 2019.
| DisplayHDR Performance Tier | ||||||||
| TRUE BLACK | ||||||||
| 400 | 500 | 600 | 1000 | 1400 | 400 | 500 | 600 | |
| MINIMUM LUMINANCE LEVEL | ||||||||
| 10% Center Patch Test – Minimum Luminance Level (cd/m2) | 400 | 500 | 600 | 1000 | 1400 | 400 | 500 | 600 |
| Full-screen Flash Test – Minimum Luminance Level (cd/m2) | 400 | 500 | 600 | 1000 | 1400 | 250 | 300 | 350 |
| Full-screen Long-duration Test – Minimum Luminance Level (cd/m2) | 320 | 320 | 350 | 600 | 900 | 250 | 300 | 350 |
| BLACK LEVEL | ||||||||
| Dual Corner Box Test – Screen Center, Maximum Luminance Level (cd/m2) | 0.4 | 0.1 | 0.1 | 0.05 | 0.02 | 0.0005 | 0.0005 | 0.0005 |
| Dual Corner Box Test, Both White Corners, Minimum Luminance Level (cd/m2) | 300 | 375 | 450 | 750 | 1050 | 300 | 375 | 450 |
| ACTIVE DIMMING/CHECKERBOARD TEST | ||||||||
| Active Dimming – Ratio of maximum white to black of a 50cd/m2 checkerboard (stops) | 11 | 11.6 | 12 | 13 | 13.5 | N/A | N/A | N/A |
| Active Dimming – Ratio of maximum white to black of a 5cd/m2 checkerboard (stops) | 12 | 12.6 | 13 | 14 | 14.5 | N/A | N/A | N/A |
| Checkerboard – Max Black Level at Full Luminance (True Black only) | N/A | N/A | N/A | N/A | N/A | 0.0005cd/m2 | ||
| COLOR GAMUT AND MINIMUM LUMINANCE SPECIFICATIONS | ||||||||
| ITU-R BT.709 Coverage for Both 10% and Full-screen Color Patches | 95% | 99% | 99% | 99% | 99% | 99% | 99% | 99% |
| DCI-P3 CIE D65e Coverage for Both 10% and Full-screen Color Patches | N/A | 90% | 90% | 90% | 95% | 90% | 90% | 90% |
| Combined Color Luminance (Lr + Lg + Lb) 10% Color Patch Test (cd/m2) | 400 | 500 | 600 | 1000 | 1400 | 400 | 500 | 600 |
| Combined Color Luminance (Lr + Lg + Lb) Full-screen Color Test (cd/m2) | 320 | 320 | 350 | 600 | 900 | 250 | 300 | 350 |
| MINIMUM BIT-DEPTH SPECIFICATIONS | ||||||||
| 10-bit Video Signal, per Channel | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ |
| Minimum Driver-IC Bit Depth (+2b Dithering FRC) | 8b | 8b+2 | 8b+2 | 8b+2 | 8b+2 | 8b+2 | 8b+2 | 8b+2 |
| Minimum 8-bit Digital-to-analog Conversion | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ |
| Backlight Control 8-bit Accuracy | ✔ | ✔ | ✔ | ✔ | ✔ | N/A | N/A | N/A |
| DISPLAYHDR RISE-TIME SPECIFICATIONS | ||||||||
| Maximum Number of Frames for Rise from Black to Maximum Luminance | 8 | 8 | 8 | 8 | 8 | 2 | 2 | 2 |
| LUMINANCE AND WHITE POINT ACCURACY | ||||||||
| Permitted Maximum Delta-ITP error for tests at 5 and 15cd/m2 | 20 | 20 | 20 | 20 | 20 | 20 | 20 | 20 |
| Permitted Maximum Delta-ITP error for tests at 50, 100, and 200cd/m2 | 15 | 15 | 15 | 15 | 15 | 15 | 15 | 15 |
| Permitted Maximum Delta-ITP error for tests at 50% of Tier Level maximum | N/A | 15 | 15 | 15 | 15 | N/A | 15 | 15 |
Overview of Performance Criteria Under CTS 1.1
DisplayHDR v1.1 includes performance evaluation of all of the following features:
- Peak White Level – includes several tests for the peak white luminance level. Among them is a 10% center patch that is used to measure the maximum luminance level achievable by the display for a relatively small segment of the screen. We also test a full-screen luminance level, both in a quick flash test, which represents very brief usage such as an explosion in a movie or game, and the long-term stable luminance levels in full screen usage.
- Black Level – tests the darkest achievable black, when also simultaneously displaying maximum white in two corners. Displays with better local dimming solutions achieve superior results in this test.
- Active Dimming – version 1.1 introduced active dimming performance levels, a feature that can reduce power consumption and yield significantly darker black levels. This test is measured by comparing two different test images: a white 10% box (as used in the Peak White Level test), and the black level measured in a checkerboard pattern using black/grey checkerboard where the grey level is only 5 cd/m2. With a maximum luminance on screen of 5 cd/m2, this test provides the opportunity for the dimming to greatly reduce the backlight power and yield high ratios of active dimming from the white test image using maximum white levels. The results are measured in stops, which represent powers of 2.
- Color Gamut – tests the total color coverage (area) of the display, as a ratio of DCI-P3, using the DisplayID/EDID primary as the source to Windows. This measurement thus represents the ratio of DCI-P3 color gamut achieved under normal HDR usage in Windows.
- Combined Color Luminance – validates that the display can achieve full color volume at the full logo level luminance.
- Rise Time – ensures that the display can rapidly adapt to quickly changing luminance levels so that scenarios where luminance levels change rapidly are faithfully reproduced.
- Luminance and White Point Accuracy – since the pixel values represent an absolute luminance value in HDR, unlike SDR, this test ensures that the display correctly follows the EOTF-2084 luminance curve. The test simultaneously checks that the white point is correctly at D65 at each of the test points, specifying the tolerance in Delta-ITP values, as is suitable for HDR color and luminance evaluation.