公开(公告)号：DE69718345T2

公开(公告)日：2003-12-24

申请号：DE69718345

申请日：1997-09-29

Applicant: ST MICROELECTRONICS ASIA

Inventor： DESPREZ-LE GOARANT YANN ,  CHUA KAH

IPC: H04N9/68 ,  H04N9/77

Abstract: PCT No. PCT/SG97/00047 Sec. 371 Date Aug. 13, 1999 Sec. 102(e) Date Aug. 13, 1999 PCT Filed Sep. 29, 1997 PCT Pub. No. WO98/20683 PCT Pub. Date May 14, 1998This invention relates to the color matching function used in connection with the luminance or white stretch function in a television video processor. Automatic adjustment in the amplitude of the color difference signals is provided to compensate for the effect of the stretch of the luminance signal in a provision called color matching. The general principal of color matching being, any percentage change in the amplitude of the luminance signal due to the white stretch effect, must be balanced by the same percentage changes in the color difference signal so that the ratio of the color signals can be maintained after matrixing. This accomplished by compensating the color difference signals by a varying amount that decreases with increasing the input luminance signal level when the level of the input luminance signal is above said selected threshold.

公开(公告)号：DE69718345D1

公开(公告)日：2003-02-13

申请号：DE69718345

申请日：1997-09-29

Applicant: ST MICROELECTRONICS ASIA

Inventor： DESPREZ-LE GOARANT YANN ,  CHUA KAH

IPC: H04N9/68 ,  H04N9/77

Abstract: PCT No. PCT/SG97/00047 Sec. 371 Date Aug. 13, 1999 Sec. 102(e) Date Aug. 13, 1999 PCT Filed Sep. 29, 1997 PCT Pub. No. WO98/20683 PCT Pub. Date May 14, 1998This invention relates to the color matching function used in connection with the luminance or white stretch function in a television video processor. Automatic adjustment in the amplitude of the color difference signals is provided to compensate for the effect of the stretch of the luminance signal in a provision called color matching. The general principal of color matching being, any percentage change in the amplitude of the luminance signal due to the white stretch effect, must be balanced by the same percentage changes in the color difference signal so that the ratio of the color signals can be maintained after matrixing. This accomplished by compensating the color difference signals by a varying amount that decreases with increasing the input luminance signal level when the level of the input luminance signal is above said selected threshold.