Datavideo iCAST MINI Instruction Manual page 44

10. Graphic Key: This option allows you to set the Graphic Key. Originally, the 4
preset positions in "CAMERA>Position 1/2/3/4" will capture the image which is
shot by the camera to be the thumbnail of the four preset positions in the
"Home" interface. However, you can select your desired image in the "Graphic
Key" option to replace the original thumbnail. Please follow the steps below
for setting the "Graphic Key" thumbnail.

Please tap the "Graphic Key" option.
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