Method for determining environmental brightness to control display brightness in mobile communication terminal including camera having automatic gain control function, and method for controlling display brightness using the same
US7158173B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 15, 2002 |
| Grant date | Jan 2, 2007 |
| Priority date | — |
| Expiry date | Apr 12, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/63
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Disclosed is a method for determining environmental brightness to appropriately control display brightness according to variations of the environmental brightness in different places in a mobile communication terminal including a camera having an automatic gain control (AGC) function, and a method for controlling the display brightness using the same, including the steps of calculating a luminance average of a center region of a photographed screen corresponding to an AGC reference region and a luminance average of an edge region except for the center region as brightness values from an image signal generated by photographing of the camera, comparing the brightness value of the edge region with a previously-set dark environmental critical value, comparing the brightness value of the center region with the brightness value of the edge region according to the comparison result, and determining that the environmental brightness is one of the bright state and the dark state, extracting luminance elements from an image signal which will be transmitted to a display, calculating a histogram of the luminance elements, and performing brightness contrast stretching, controlling the display b…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.