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hist hacking

This commit is contained in:
John Cupitt 2010-03-26 14:42:44 +00:00
parent 5c02d91f93
commit f0f75b4093
1 changed files with 6 additions and 59 deletions
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65
libvips/histograms_lut/tone.c
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@ -1,62 +1,4 @@
/* @(#) Various functions relating to tone curve adjustment.
* @(#)
* @(#) im_tone_build: generate tone curve for adjustment of LabQ image. LUT we
* @(#) make is always 1024 elements, each element is a LabS L value.
* @(#)
* @(#) Base parameters:
* @(#)
* @(#) Lb - black point
* @(#) Lw - white point (both [0,100])
* @(#)
* @(#) Ps - shadow point
* @(#) Pm - mid-tone point
* @(#) Ph - highlight point
* @(#)
* @(#) All 0-1, meaning max of shadow section of curve should be positioned
* @(#) at Lb+Ps(Lw-Lb), etc. Suggest Lb, Lw should be set by histogram
* @(#) analysis to 0.1% and 99.9%; Ps, Pm, Ph should be 0.2, 0.5, 0.8.
* @(#)
* @(#) Main parameters:
* @(#)
* @(#) S - shadow adjustment factor (+/- 30)
* @(#) M - mid-tone adjustment factor (+/- 30)
* @(#) H - highlight adjustment factor (+/- 30)
* @(#)
* @(#) Usage:
* @(#)
* @(#) int
* @(#) im_tone_build(
* @(#) IMAGE *lut,
* @(#) double Lb, double Lw,
* @(#) double Ps, double Pm, double Ph,
* @(#) double S, double M, double H )
* @(#)
* @(#) Returns 0 on success and -1 on error
* @(#)
* @(#) im_tone_map: map just the L channel of a LabQ or LabS image through
* @(#) a LUT.
* @(#)
* @(#) Usage:
* @(#)
* @(#) int
* @(#) im_tone_map( IMAGE *in, IMAGE *out, IMAGE *lut )
* @(#)
* @(#) Returns 0 on success and -1 on error
* @(#)
* @(#) im_tone_analyse: find the histogram of a LabS or LabQ image and use
* @(#) that to set the Ln and Lw parameters of im_tone_build()
* @(#)
* @(#) Usage:
* @(#)
* @(#) int
* @(#) im_tone_analyse(
* @(#) IMAGE *in,
* @(#) IMAGE *lut,
* @(#) double Ps, double Pm, double Ph,
* @(#) double S, double M, double H )
* @(#)
* @(#) Returns 0 on success and -1 on error
* @(#)
/* Various functions relating to tone curve adjustment.
*
* Author: John Cupitt
* Written on: 18/7/1995
@ -68,6 +10,9 @@
* 11/7/04
* - generalised to im_tone_build_range() ... so you can use it for any
* image, not just LabS
* 26/3/10
* - cleanups
* - gtkdoc
*/
/*
@ -483,6 +428,8 @@ im_tone_map( IMAGE *in, IMAGE *out, IMAGE *lut )
}
/* Find histogram of in, and use that to set Lb, Lw levels.
* @(#) im_tone_analyse: find the histogram of a LabS or LabQ image and use
* @(#) that to set the Ln and Lw parameters of im_tone_build()
*/
int
im_tone_analyse(