SDL_SetGammaRamp(3) SDL API Reference SDL_SetGammaRamp(3)NAME
SDL_SetGammaRamp - Sets the color gamma lookup tables for the display
SYNOPSIS
#include "SDL.h"
int SDL_SetGammaRamp(Uint16 *redtable, Uint16 *greentable, Uint16 *bluetable);
DESCRIPTION
Sets the gamma lookup tables for the display for each color component. Each table is an array of 256 Uint16 values, representing a mapping
between the input and output for that channel. The input is the index into the array, and the output is the 16-bit gamma value at that
index, scaled to the output color precision. You may pass NULL to any of the channels to leave them unchanged.
This function adjusts the gamma based on lookup tables, you can also have the gamma calculated based on a "gamma function" parameter with
SDL_SetGamma.
Not all display hardware is able to change gamma.
RETURN VALUE
Returns -1 on error (or if gamma adjustment is not supported).
SEE ALSO
SDL_SetGamma SDL_GetGammaRamp
SDL Tue 11 Sep 2001, 23:01 SDL_SetGammaRamp(3)
Check Out this Related Man Page
pfsgamma(1) General Commands Manual pfsgamma(1)NAME
pfsgamma - Apply gamma correction to color or gray-scale images
SYNOPSIS
pfsgamma [--gamma <gamma> | --inverse-gamma <inv-gamma>] [--mul <multiplier>]
DESCRIPTION
Use this command to gamma correct a stream of pfs images. Gamma correction is equivalent to raising value of R, G and B (or Y for gray-
scale images) channels to 1/gamma power. More information on gamma correction can be found at:
http://www.poynton.com/notes/colour_and_gamma/GammaFAQ.html
This command can work on color images, in which case XYZ channels are transformed to RGB space, then they are gamma corrected before they
are converted back to XYZ. For gray-scale images (only Y channel and XZ missing) gamma correction is applied only to Y channel.
Data can be multiplied by an optional multiplier before gamma correction.
Note: gamma correction will set the 'LUMINANCE' tag to 'DISPLAY' thus cancelling any sRGB correction when saving to LDR files (like PPM,
TIFF). This will also cause a warning message when saving to HDR files, because the intensities after gamma correction are not linearly
related to luminance any more.
OPTIONS --gamma <gamma>, -g <gamma>
Perform gamma correction (input^(1/gamma)). This can be used to convert images from relative luminance or radiance to pixel values.
Default value: 1.0
--inverse-gamma <inv-gamma>, -i <inv-gamma>
Perform inverse gamma correction (input^(gamma)). This can be used to convert images from pixel values to relative radiance or lumi-
nance.
--mul <mul>, -m <mul>
Multiply data by this value before gamma correction. Default value: 1
EXAMPLES
pfsin memorial.hdr | pfsgamma -g 1.8 -m 10 | pfsout memorial_gc.ppm
Multiply memorial image by 10, gamma correct it and save to memorial_gc.ppm.
SEE ALSO pfsin(1)pfsout(1)pfsdisplayfunction(1)BUGS
Please report bugs and comments to the pfstools discussion group (http://groups.google.com/group/pfstools).
pfsgamma(1)
I have a huge matrix file containing some 1.5 million rows and 6000 columns. The matrix looks something like this:
1 2 3
4 5 6
7 8 9
3 4 5
I want to add all the numbers in the columns of this matrix and display the result to my stdout. This means that the numbers in the first column are:
... (2 Replies)
Hi,
Just trying to get to grips with sed and awk for some reporting for work and I need some assistance:
I have a file that lists policy names on the first line and then on the second line whether the policy is active or not.
Policy Name: Policy1
Active: yes
Policy... (8 Replies)
version info :
vi availabe with RHEL 5.4
I have a text file with 10,000 lines. I want to copy lines from 5000th line to 7000th and redirect to a file. Any idea how I can do this?
Note:
The above scenario is just an example. In my actual requirement, the file has 14 million lines and I want... (9 Replies)
Hi everyone,
I know the following questions are noobish questions but I am asking them because I am confused about the basics of history behind UNIX and LINUX.
Ok onto business, my questions are-:
Was/Is UNIX ever an open source operating system ?
If UNIX was... (21 Replies)
Hello,
I couldn't find an actual introduction thread, so I decided to just put this here.
I go by d0wngrade online. I have been programming in multiple languages for about 15+ years. I started with standard web design languages like HTML and CSS, but I then advanced from design to development... (2 Replies)
Hi guys...
The first active code line in AudioScope.sh is set -u .
This causes a complete exit if a variable is used/found but has not been allocated at the start of the program.
However, apart from writing code to do the task, is there a switch to to check which variables have been... (17 Replies)
Hi.
In thread https://www.unix.com/shell-programming-and-scripting/267833-grouping-counting.html rovf and I had a mini-discussion on grep and awk.
Here is a demo script that compares the awk and grep approaches for this single problem:
#!/usr/bin/env bash
# @(#) s2 Demonstrate group... (1 Reply)
Hello,
I have to fish out some specific columns from a file based on the header value. I have the list of columns I need in a different file. I thought I could read in the list of headers I need,
# file with header names of required columns in required order
headers_file=$2
# read contents... (11 Replies)
For those interested in installing dash shell on OSX Lion to help test POSIX compliancy of shell scripts, it is quite easy. I did it like this:
If you don't have gcc on your system:
0. Download and install the Command Line Tools for Xcode package from Sign In - Apple *
1. Download the dash... (2 Replies)
Hello and thanks in advance for any help anyone can offer me
I'm trying to learn the find command and thought I was understanding it... Apparently I was wrong. I was doing compound searches and I started getting weird results with the -size test. I was trying to do a search on a 1G file owned by... (14 Replies)
I have data of an excel files as given below,
file1
org1_1 1 1 2.5 100
org1_2 1 2 5.5 98
org1_3 1 3 7.2 88
file2
org2_1 1 1 2.5 100
org2_2 1 2 5.5 56
org2_3 1 3 7.2 70
I have multiple excel files as above shown.
I have to copy column 1, column 4 and paste into a new excel file as... (26 Replies)
Dear All,
Taking a break from Vue.js coding for the site, SEO and YT videos; and hopefully addressing some well deserved criticism from some here that I have been too focused on the visual aspects of the forums versus the substance and the community....
While the "current generation... (9 Replies)
Hi all...
Well guys and gals, I jumped in at the deep end and found things that PERL cannot do by default.
Many tricky terminal escape codes are not catered for so I had to create workarounds.
One thing I searched for was this:
Passing perl variable to shell command
AND, @Neo this was... (15 Replies)