madVR User Guide

LightSpace CMS can be integrated with madVR for accurate profiling and LUT based calibration for HTPC home cinema applications.

The following instructions are for calibration of displays connected to a madVR based Home Cinema system using LightSpace CMS.


Initial Operation

madTPG Calibration

Calibration of displays connected to a madVR based Home Cinema system using LightSpace CMS is exceptionally simple, with integration for profiling and LUT upload.

  • Open madTPG.exe, which is madVR's Test Patch generator, from the madVR install folder
  • If using MadTPG over a network check the mad* tray icon via a 'right click', and make sure 'LAN Access' is Enabled
    (If Disabled, Enable it, and re-start madVR)
  • If wanted, 'videoluts' and '3dluts' can be disabled via the madTPG menu, although LightSpace will manage this later
  • Use a double click on madTPG to make full-screen, with no surround or menu area
  • Within LightSpace Navigate to File/Upload, and select the madVR option from the 'Select the device type' drop-down window.
    (You will need to manually enter the PC name or IP address of the system madVR is installed on. If on the same PC as LightSpace this will be 'localhost'.)
  • If there is no LUT active with LightSpace the NULL Cube option will be ticked and greyed-out, but is operational.
    (As no other LUT is available the ONLY option is the NULL Cube)
  • Select the colour space 'Slot' into which the LUT will be uploaded
    (Due to the way madVR works you must use the correct colour space slot.)
  • To make sure no LUT is already active within madVR select 'Upload', with the NULL Cube box ticked.
    (This will NULL the colour space slot selected previously.)
  • Using the 'Calibration Patches' options select the desired patch size and background level to use, as well as the desired APL mode.
    • Area % - sets the FG patch size as an area percentage.
    • BG % - sets the BG grey level.
    • APL CONST - sets the BG to a constant grey value as specified by BG %.
    • APL GAMMA - sets the BG to an inverse of the FG colour value, based on the slot's colour space gamma, targeting the BG % value.
    • APL LIN - sets the BG to an inverse of the FG colour value using a linear range, targeting the BG % value.
  • Close the 'Upload' menu.
madVR Upload

The Upload menu is located under 'File/Upload'.

Prior to profiling make sure the the Brightness and Contrast settings for the display have been set as per the Initial Display Set-up guide.


Null Cube

When 'Null Cube' is used, both the 3D LUT in the selected colour space Slot, and the display's VCGT 1D LUT are set to Null/Off. Should the VCGT be desired to be active, rather than using the 'Null Cube' tick box upload a real Null/Bypass 3D LUT (generated via File/New), as that will not disable the VCGT, and will only 'null' the 3D LUT.

Although the option is labeled 'Null Cube', an actual Cube (LUT) is not necessarily loaded into the system, depending on the system's capabilities/options. A 'reset' command may be issued, rather than an actual Cube file uploaded.


HDR Operation

The 'Options' button opens a new pop-up menu for HDR operation, enabling control of madVR HDR values.

madVR Options
  • The Enable HDR tick box enables all the HDR options.
  • The HDR LUT output selects the LUT Gamma the display expects when uploading a LUT.
  • HDR Info Frame dropdown provides a set of pre-set values for the different colour spaces, as well as a Custom option.
    When set to 'Custom' user values can be entered.
  • The Max/Min DML and Max CLL/FALL values are always user entered.
  • The 'Upload Info Frame' button uploads the values into madTPG.

Profiling & Calibration Operation

To activate the madVR Patch Generator navigate to the desired profiling mode within LightSpace - Calibration Interface, or Display Characterisation.

When the patch window is activate within LightSpace (the LightSpace CMS internal floating patch window has been made active by clicking the small colour display box when using Quick Profiling or Manual Measure modes) the madVR patch generator will mimic the colour displayed, using the patch size pre-set via the 'Upload' window.

Profiling can then be performed as normal, using the probe connected to LightSpace, and with madVR displaying the required patches on the display screen.
(The border around the FG patch is a function of madVR and cannot be disabled.)


LUT Upload

After profiling a Calibration LUT can be generated as normal, and with the LUT held within LightSpace navigate back to the 'Upload' menu, and with the 'NULL Cube' tick box un-ticked, the present LUT displayed within LightSpace can be 'Uploaded' into the selected colour space 'Slot' within madVR

In this way, many different LUTs can be held within LightSpace CMS and quickly and easily uploaded into madVR as needed.
(Note: The Temp slot - Temporary - can be used to avoid overwriting any existing LUTs while testing workflows, etc., but the LUT will be lost when madTPG is closed.)


madVR LUT and VideoScale

For all generated LUTs, after the calibration LUT has been generated via LightSpace CMS in the normal way, use the 'Edit/LUT Manipulation/VideoScale' functions to format the LUT data as required, using any of the five VideoScale functions as required.
(The choice of VideoScale is a user decision, and so has to be selected manually, based on the user's specific needs/requirements.)

Normally, for data range image path workflows, VideoScale would not be needed. However, madVR uses a legal video level workflow for both video and data ranges, so all LUTs loaded into madVR will need to have one of the VideoScale functions applied regardless of TV Legal or Data ranges being used. As there are five VideoScale options, the selection must be a user selectable one.


Additional Technical & Support Info.

Additional Software Required: LightSpace CMS
LightSpace CMS Demo: Downloads
Manufacturer Download: madVR
Manufacturer User Guide: madVR User Guide
German language version of this page: displaycalibration.de

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