HDMI is a common interface used especially in monitors, laptops, and TVs. Close to 2000 manufacturers have adopted the HDMI interface resulting as much as three billion devices manufactured around the world. HDMI interface is managed by the HDMI organization.


From HDMI 1.0 to HDMI 2.1

HDMI 1.0 was launched in 2002. HDMI 2.0 was launched in 2013 enabling resolutions up to 4K. The latest, HDMI 2.1 interface, released in 2019, enables resolutions up to 10K@120Hz.

Unigraf has followed the evolution of the HDMI interface with UCD-300 series’ 4K capable video analyzers & generators and with the latest HDMI test tool, the HDMI 2.1 (FRL) capable UCD-422.

E-Learning Center: HDMI 2.1 – All you need to know

What to Test in HDMI Interface?

Testing of the HDMI interface includes all the basic video interface tests such as Video (CRC based video tests), Audio, Link, EDID, and HDCP encryption. There are also, HDMI specific features such as the TMDS signal and HDMI connector that needs to be addressed while testing HDMI devices. Unigraf’s UCD series test tools’ test coverage includes all necessary tests for testing the HDMI interface. For more detailed information about testing HDMI transmitters and receivers, please refer to the links below.

Application: Testing HDMI transmitters

Application: Testing HDMI receivers

E-learning Center: Ensuring Functionality of HDMI interface

Signal continuity in Connector Pins

Testing of signal continuity on connector pins is an essential part of ensuring the functionality of HDMI transmitters (e.g. game consoles, Blu-ray players).  Modern receiver devices can have high-quality receiver chips that can correct a defected signal. Even if one monitor or TV shows the video signal just fine, there can still be defects in the connector pins because of the bad soldering or assembly of the connector. This means that the transmitter device may not work with all receiver devices available on the market. Only with proper test tools, can you make sure that your transmitter device provides flawless video signal that can be shown on all receiver devices. This testing can be automated for production line testing purposes.

E-learning Center: Testing Signal continuity

Dolby Vision™ for HDMI

Dolby has worked closely with industry leaders over the last 50 years to make the stories and experiences as engaging as possible—first with noise reduction, then 5.1 surround and 7.1 surround, and now with Dolby Vision™. Dolby Vision™ transforms the way you experience movies, TV shows, and games with incredible brightness, contrast, and color that bring entertainment to life before your eyes. By fully leveraging the maximum potential of new cinema projection technology and new TVs’ display capabilities, Dolby Vision™ delivers high-dynamic-range (HDR) and wide-color-gamut content. The result is a refined, lifelike image that will make you forget you are looking at a screen.

Unigraf UCD-323 has been approved as an official Dolby Vision™ compatibility test tool. In the compatibility test for Dolby Vision™ Unigraf will provide playback and capturing of the test video and audio content with UCD-323. Further, Dolby will provide customers with the SDK (Software Development Kit) that enables analyzing the Dolby Vision™ video captured with the UCD-323. As of now, Dolby Vision™ testing is available for the HDMI interface. UCD-323 also supports Dolby Vision signaling test using Dolby Vision VSIF and Dolby Vision Vendor-Specific Extended Metadata Packets (EMP) using TMDS. With the Dolby SW package, UCD-323 is a mandatory tool for any e.g. television or monitor manufacturer that is willing to have a Dolby Vision™ certificate on their products.

Source: Dolby (2016)

Enhanced Gaming Features

Enhanced gaming and media features ensure an added level of smooth and seamless motion and transitions for gaming, movies and video. Many of these features are already available in TVs and game consoles in the market today and will become more common as HDMI 2.1-enabled devices continue to be released. Two of the enhanced gaming features are Variable Refresh Rate and Auto Low Latency Mode.

  • Variable Refresh Rate (VRR) reduces or eliminates lag, judder, and frame tearing for more fluid and better-detailed gameplay. VRR enables a gaming source such as a console or computer to deliver video frames as fast as it can, which in many cases is slower than the normal static refresh rate.
  • Auto Low Latency Mode (ALLM) enables the ideal latency setting to automatically be set allowing for smooth, lag-free, and uninterrupted viewing and interactivity. In many cases, this is referred to as game mode, and it usually has to be set manually which involves going through menus and settings and then switching back again for normal viewing.

Source: HDMI.org

Unigraf’s HDMI 2.1 Test Tool UCD-422 supports enhanced gaming features VRR and ALLM.

More information: UCD-422

Automated Testing

All of Unigraf’s HDMI Test Tools support automated testing. Tests for e.g. video, audio, link, EDID, and HDMI connector pins can be fully automated. There are different options for running automated tests on HDMI devices. Click the link below for detailed information on test automation options.

Application: Test Automation


Unigraf HDMI Test Tools

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