From 71abbdaeb1bca1c62bbae4cb4d5ccbc1ecea014e Mon Sep 17 00:00:00 2001 From: Mattias Andrée Date: Thu, 8 Jun 2017 00:06:26 +0200 Subject: Add man pages for most colour models MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signed-off-by: Mattias Andrée --- LIBCOLOUR_YUV.7 | 64 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 64 insertions(+) create mode 100644 LIBCOLOUR_YUV.7 (limited to 'LIBCOLOUR_YUV.7') diff --git a/LIBCOLOUR_YUV.7 b/LIBCOLOUR_YUV.7 new file mode 100644 index 0000000..784a60b --- /dev/null +++ b/LIBCOLOUR_YUV.7 @@ -0,0 +1,64 @@ +.TH LIBCOLOUR_YUV 7 libcolour +.SH NAME +LIBCOLOUR_YUV - YUV +.SH DESCRIPTION +YUV colours are presented with either of +.nf + + \fBtypedef struct libcolour_yuv_f libcolour_yuv_f_t;\fP + \fBtypedef struct libcolour_yuv_lf libcolour_yuv_lf_t;\fP + \fBtypedef struct libcolour_yuv_llf libcolour_yuv_llf_t;\fP + +.fi +These +.BR struct s +use +.BR float , +.BR double , +and +.BR long\ double , +respecitively, for the values stored in them, +and are otherwise identical. +.B struct libcolour_yuv_f +is defined as +.nf + + \fBstruct libcolour_yuv_f {\fP + \fBenum libcolour_model\fP \fImodel\fP\fB;\fP + \fBfloat\fP \fIY\fP\fB;\fP + \fBfloat\fP \fIU\fP\fB;\fP + \fBfloat\fP \fIV\fP\fB;\fP + \fB};\fP + +.fi +.I .model +shall be set to +.BR LIBCOLOUR_YUV . +In +.BR union\ libcolour_colour_f , +.BR union\ libcolour_colour_lf , +and +.BR union\ libcolour_colour_llf , +.I .yuv +is used for YUV colours. +.P +.IR .Y , +.IR .U , +and +.I .V +hold the Y (luma), U, and V values, respectively. +.P +Y is 0 in black and 1 in white. +U is the difference (with a factor) between Y and blue. +V is the difference (with a factor) between Y and red. +.P +YUV is additive, since it is linearly isomorphic +to CIE 1931 XYZ. It's white point is the +CIE Standard Illuminant D65. Additionally, conversion +between YUV and YDbDr is done with a diagonal matrix +multiplication. +.SH SEE ALSO +.BR libcolour (7) +.SH AUTHORS +Mattias Andrée +.RI < maandree@kth.se > -- cgit v1.2.3-70-g09d2