From 4baaecb4ff220d6decb959bef14d91385cbba1ad Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Sat, 27 Aug 2022 23:34:52 +0300 Subject: utils: rkisp1: gen-csc-table: Specify coefficients with full precision The Rec01, Rec709, Rec2020 and SMTPE 240M standards specify the Cb and Cr coefficients of the RGB to Y'CbCr conversion matrix using a quotient of two values. Use the exact same formulas instead of hardcoding the division results with a lower precision. Signed-off-by: Laurent Pinchart Reviewed-by: Florian Sylvestre Reviewed-by: Umang Jain --- utils/rkisp1/gen-csc-table.py | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/utils/rkisp1/gen-csc-table.py b/utils/rkisp1/gen-csc-table.py index ca0187ec..2fb70274 100755 --- a/utils/rkisp1/gen-csc-table.py +++ b/utils/rkisp1/gen-csc-table.py @@ -12,24 +12,24 @@ import sys encodings = { 'rec601': [ - [ 0.2990, 0.5870, 0.1140 ], - [ -0.1687, -0.3313, 0.5 ], - [ 0.5, -0.4187, -0.0813 ] + [ 0.299, 0.587, 0.114 ], + [ -0.299 / 1.772, -0.587 / 1.772, 0.886 / 1.772 ], + [ 0.701 / 1.402, -0.587 / 1.402, -0.114 / 1.402 ] ], 'rec709': [ - [ 0.2126, 0.7152, 0.0722 ], - [ -0.1146, -0.3854, 0.5 ], - [ 0.5, -0.4542, -0.0458 ] + [ 0.2126, 0.7152, 0.0722 ], + [ -0.2126 / 1.8556, -0.7152 / 1.8556, 0.9278 / 1.8556 ], + [ 0.7874 / 1.5748, -0.7152 / 1.5748, -0.0722 / 1.5748 ] ], 'rec2020': [ - [ 0.2627, 0.6780, 0.0593 ], - [ -0.1396, -0.3604, 0.5 ], - [ 0.5, -0.4598, -0.0402 ] + [ 0.2627, 0.6780, 0.0593 ], + [ -0.2627 / 1.8814, -0.6780 / 1.8814, 0.9407 / 1.8814 ], + [ 0.7373 / 1.4746, -0.6780 / 1.4746, -0.0593 / 1.4746 ], ], 'smpte240m': [ - [ 0.2122, 0.7013, 0.0865 ], - [ -0.1161, -0.3839, 0.5 ], - [ 0.5, -0.4451, -0.0549 ] + [ 0.2122, 0.7013, 0.0865 ], + [ -0.2122 / 1.8270, -0.7013 / 1.8270, 0.9135 / 1.8270 ], + [ 0.7878 / 1.5756, -0.7013 / 1.5756, -0.0865 / 1.5756 ], ], } -- cgit v1.2.1