Summary of DisplayHDR Specs under CTS 1.2

The table below is a summary of the specifications for the VESA DisplayHDR and DisplayHDR True Black standards as they are updated by CTS 1.2 released on May 7th, 2024. A brief description of the new criteria follows the table. The complete description of these specifications and the VESA certification test criteria are available in the DisplayHDR CTS documents which are available for download.

DisplayHDR Performance Tier
TRUE BLACK
400 500 600 1000 1400 400 500 600
MINIMUM LUMINANCE LEVEL
8% Center Patch Test Luminance with 2% APL Background – 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 99% 99% 99% 99% 99% 99% 99% 99%
DCI-P3 CIE (D65) Coverage for Both 10% and Full-screen Color Patches 90% 95% 95% 95% 95% 95% 95% 95%
Additive RGB Color Luminance (Lr + Lg + Lb) 10% Color Patch Test (cd/m2) 400 500 600 1000 1400 400 500 600
Additive RGB 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) 8b+2 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 1 and 5 cd/m2 20 20 20 20 20 20 20 20
Permitted Maximum Delta-ITP error for tests at 15 cd/m2 15 15 15 15 15 15 15 15
Permitted Maximum Delta-ITP error for tested luminances at 50 and above cd/m2 10 10 10 10 10 10 10 10
STATIC CONTRAST RATIO
1D backlights (min ratio) 1,300 : 1 7,000 : 1 8,000 : 1 N/A N/A N/A N/A N/A
2D backlights (min ratio) N/A N/A N/A 30,000 : 1 50,000 : 1 N/A N/A N/A
XRITE® COLOR TEST PATCHES
Permitted Maximum Delta-ITP color error at 50, 100 and 50% of tier 8 8 8 6 6 8 8 8
HDR VS SDR BLACK LEVEL
CRHDR > 0.9 x CRSDR
BLACK CRUSH
Display luminance increasing 0, 0.05, 0.1, 0.3, 0.5 cd/m2 Measure and view monotinically increasing luminance
SUBTITLE FLICKER
Maximum difference in luminance of patch when subtitle is ON vs OFF 13 13 13 10 10 10 10 10

 

Download this summary table in PDF format

 

Overview of Performance Criteria Under CTS 1.2

DisplayHDR v1.2 includes performance evaluation of all of the following features:

  • Peak White Level – includes several tests for the peak white luminance level. New for V1.2, an 8% center patch is used to measure the maximum luminance level achievable by the display for a relatively small segment of the screen, while also displaying a lower luminance image across the rest of the screen. We also test a full-screen maximum 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 – this test is measured by comparing two different test images: the 8% center patch from 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. Test requirements have been increased for version 1.2.
  • 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 correct at D65 at each of the test points, specifying the tolerance in Delta-ITP values, as is suitable for HDR color and luminance evaluation. Version 1.2 increases the range of testing by 10X, and simultaneously tightens the tolerance levels, ensuring even greater levels of accuracy.
  • Static Contrast Ratio – new for V1.2, single image contrast ratios have been introduced where we measure the black and white points of a single image (unlike the Active Dimming test, which compares the dimming ratio between the results of two different images). This test measures the on-scene contrast ratio achievable. Different test patterns are used for the different performance levels and, by doing so, this requires 1D local dimming (or better) for DisplayHDR 500 and 600 levels, and 2D local dimming (or better) for DisplayHDR 1000 and above. The DisplayHDR 400 level also benefits from this new test in that the contrast ratio requirement at the 400 level requires either a substantial increase in native panel contrast ratio versus CTS v1.1, or 1D local dimming.
  • Color Accuracy – new for V1.2, we introduce color accuracy tests, using X-Rite’s ColorChecker SV set of 96 colors, at each of three different HDR luminance levels to test almost 300 colors!
  • HDR vs SDR Black Level – new for V1.2, this test is utilized to verify that the black level achieved in OS-HDR mode, for SDR applications, is at least as good as the black level achieved in OS-SDR mode.
  • Black Crush – new for V1.2, this test verifies that the display can render shadow detail without crushing dark shadows to black.
  • Subtitle Flicker – new for V1.2, this test verifies that the local dimming, which is the result of a combination of backlight power control and LCD transparency control, is correctly modulated to ensure that as elements of a HDR scene abruptly change in luminance level, the output luminance level of other scene elements that should remain stable indeed remain stable within the very tight tolerance specified by the CTS. The scope and impact of this test goes well beyond subtitle usage.

 

Visit the downloads page for CTS documentation and test tools

View previous-version specification summary for DisplayHDR CTS 1.1.