维奥

How to solve HDMI signal(format 1920x1080 60Hz) from graphic card not display absolute black

Related models

LVP605/LVP615 series/LVP515/LVP909 ect (HDMI input port), LVP7000/LVP609 series(DVI input port)

Phenomenon description

Connect DVI\HDMI signal(format 1920x1080_60Hz) from desktop computer or laptop with processor, output image of processor looks brighter. Even source is all black image, pixels of LED screen light up.

Analysis of cause

First is mechanism of how graphic card read EDID. HDMI input port of LVP615 support almost all resolutions below 1920x1080_60Hz of PC and television video signal format, these information are contained in EDID of corresponding port. After DVI or HDMI output port of graphic card connect with processor, computer read DVI/HDMI EDID data of processor, then output signal supported by processor.

Resolution 1920x1080_60Hz exist in both PC(VESA) and television video format, in general, including RGB Full color (0~255)，RGB Limited color (16~235), YCbCr(4: 4: 4) and YCbCr(4: 2: 2) and other different formats.

If DVI or HDMI port of these models only support one of PC or television standards, then graphic card read corresponding EDID, output only corresponding format, "not absolute black" issue will not occur. But these models support both two standards, after graphic card read EDID information, it will by default output wrong signal format, causing "not absolute black" issue.

Solution

To solve this issue, need to change DVI/HDMI color parameters of graphic card. Commonly, change output settings to RGB Full (0~255) or YCbCr will get things work. Different brands of graphic cards, even different graphic cards of same brands, settings need to be changed are not same. In the following, introduce setup steps using different graphic cards.

Intel Graphic Card 1

Steps:

In desktop mode, right-click the Desktop. Then, select “Intel® Graphics Settings” to enter control panel of Intel graphic card. "Display" - “Information”, select corresponding display(connect with LVP615-HDMI, so select this display).

Under "Color" interface, click checkbox of "YCbCr" to turn it on.

Intel Graphic Card 2

Steps:

In desktop mode, right-click the Desktop. Then, select “Intel® Graphics Settings” to enter control panel of Intel graphic card. "Display" - "General Settings" menu, select corresponding display(connect with LVP615-HDMI, so select this display), under "Quantization Range", click checkbox  of "Full Range". Or under "Color Settings" menu, click checkbox “Enable” of "YCbCr". Both methods can solve issue.

NVIDIA Graphic Card

Steps:

In desktop mode, right-click the Desktop. Then, select "NVIDIA Control Panel", under "Change resolution" menu, select corresponding display(connect with LVP615-HDMI, so select this display), under color settings, select "RGB" for Output Color Format and "FULL" for Output Dynamic range or select YCbCr444、YCbCr422 and "FULL" for Output Dynamic range, then click "Apply".

AMD Graphic Card

Steps:

Right click on your desktop and select AMD Radeon Settings, click on the Radeon Additional Settings, Radeon Additional Settings menu should open up in a separate window. Then enter "My Digital Flat-Panels" - "Pixel Format": change to "RGB 4:4:4 Pixel Format PC Standard(Full RGB)", click "Apply".

Note:interface of different graphic cards maybe not same, please search patiently, if got no relative options, please try to update driver for graphic card.