ddcutil vs LG OnScreen Control

ddcutil is a free Linux program for controlling monitor settings such as brightness, color levels and input source. It communicates with monitors through DDC/CI over I²C and supports monitors implementing MCCS over USB. Commands can find monitors, show capabilities, read or change VCP feature values, and save or restore color-related settings. The companion ddcui provides a Qt graphical interface with Summary, Capabilities and Features views, with the last allowing changes to modifiable values. For profile workflows, dumpvcp saves current settings to a file and loadvcp restores them. Developers can use the C API through libddcutil.so to read and write VCP values and handle profile-related features. The program is released under GNU GPL version 2. Setup requires the Linux kernel i2c-dev module, and non-root users need permissions to run it. It does not support laptop displays, which use a special API rather than I²C, and generally will not run in virtual machines because virtual video drivers do not implement I²C. For MCCS-over-USB table features, support is limited; the capabilities command synthesizes a response.

LG OnScreen Control is a desktop utility for managing features on certain LG monitors from Windows or macOS. It offers Screen Split, which divides the display into regions, and controls for brightness, contrast, and other monitor settings. My application Preset can change picture mode when you click a chosen application window, while Game mode settings let you adjust game-related monitor settings. The 5:9 Preview feature displays an application in a 5:9 area that you can move to a preferred position. The app can also update monitor firmware. A USB connection is required for settings and firmware updates; firmware updates also need internet access and a supported USB cable. Support depends on the monitor model, so LG advises checking its owner’s manual. The app does not support the PC’s Duplicate display setting; LG advises using Extend mode if its menu does not appear. A non-genuine cable or adapter can prevent DDC/CI communication, and using a third-party monitor may limit some features. The download is free for supported models.