the blue light spectrum is a strong signal to the human body that it is currently daytime, and it significantly impacts the circadian rhythm and melatonin production. it is thus a common desire to decrease one's exposure to it at night, especially if one already has sleep issues. as computer screens (along with white lightbulbs) are among the biggest household sources of blue light at night, a class of software exists to filter out blue and shift the colours displayed on the screen to warmer tones with more red.
filtering the whole screen is a bit much, so I won't ask you to do that. starting simple is always best, so let's just do one image. there are multiple ways to interpret "filtering out blue" and multiple ways to go about it. I will briefly go over one; however, this problem is open-ended and any solution is admissible.
your challenge, given an image, is to return the same image with less blue in it. it is not acceptable to return an image with more blue in it. as any language is allowed, there is no fixed API.
entry #1
comments 2
fuckyou.jpg JPEG image data, Exif standard: [TIFF image data, big-endian, direntries=5, width=759, height=582, orientation=upper-left, datetime=2026:06:02 19:09:38], baseline, precision 8, 759x582, components 3
entry #3
comments 0
i miss python 2.py ASCII text
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16 | import sys
from PIL import Image
def fix(filename):
image = Image.open(filename).convert("RGBA")
pixels = image.load()
width, height = image.size
for y in xrange(height):
for x in xrange(width):
colors = pixels[x,y]
pixels[x,y] = (colors[0], colors[1], 0, colors[3])
image.save(filename + "_fixed.png")
print "done"
if __name__ == "__main__":
fix(sys.argv[1])
|
entry #5
comments 0
yellow.sh ASCII text
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115 | #!/bin/sh
#
# WARNING :: BAD perfromance Sorry
#
#
#
# STDIN = Image (Blue)
# STDOUT = Image Sans (
#
# ##################
# #### ####
# ## ##
# ## ##
# ## ##
# ## ###### ##
# ## ###### ##
# ## ###### ## ###### ##
# ## ###### ##
# #### ## ## ####
# ## ###################### ##
# ## ## ## ## ## ## ##
# #### ############## ####
# ########## ##########
# ## ############################## ##
# #### ## ## ## ## ## ####
# ## ## ###### ###### ## ##
# ## #### ###### ## ###### #### ##
# ## ## ## ## ## ##
# ## ## ## ## ## ##
# ## ## #### #### ## ##
# #### ## ## ## ## ####
# ###### ############## ######
# #### ############## ####
# ##################################
# ################ ################
# ############ ############
# ###### ## ## ######
# ## #### #### ##
# ########## ##########
#
# ) Blue
#
take() {
_v="$(dd status=none bs="$1" count=1)"
test -n "$_v" || return 1
printf '%s' "$_v";
}
hex() {
od -An -tx1 | tr -d ' \n'
}
unhex() {
while true; do
_vv="$(take 2)" || break
printf '\x'"$_vv"
done
}
if command -v xxd >/dev/null 2>&1; then
hex() {
xxd -p | tr -d ' \n'
}
unhex() {
xxd -p -r
}
fi
if test -z "$(printf 'a\nna' | (read -N4 v; cat) 2>/dev/null)"; then
take() {
read -N$(($1 + 0)) _v
test -n "$_v" || return 1
printf '%s' "$_v"
}
fi
(
(
ffmpeg \
-i - \
-f rawvideo \
-pix_fmt rgba \
-y - \
3>&1 4>&2 2>&3 1>&4
) |
grep -Em1 Video: |
grep -Eom1 '[0-9][0-9]*x[0-9][0-9]*'
) 2>&1 | (
read size
echo $size
pxs=$(eval 'echo $(('"$(echo $size | tr 'x' '*')"'))')
i=0
p_a=1000
p_b=1000
hex | while :; do
take 4 || break
take 2 >/dev/null || break
printf '00'
take 2 || break
i=$(($i + 1))
p_a=$(($i * 100 / $pxs))
if test -t 2 && test $p_a -ne $p_b; then
p_b=$p_a;
printf '\r%s%%' "$p_a" >&2;
fi
done
if test -t 2; then
printf '\n' >&2
fi
) | (
read size
unhex | ffmpeg \
-f rawvideo \
-pixel_format rgba \
-video_size $size \
-i - \
-f apng \
-y - \
2>/dev/null
)
|
entry #7
comments 0
blue_light.ec Unicode text, UTF-8 text
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122 | ? Written and tested on a little endian system
? Good luck porting it to big endian
? May take some time to fully execute
"io.ec"
"utilities.ec"
"bmp.ec"
+--E ? Discard file length
>-⎚-⬟-r |
+-⛁-+ ? Sign correction
|
+-⌂-b ? Check signature and move file size backwards, we'll need that
F-b
F-b
F-b
F-⛩-+ ? Check reserved
|
+f#fB ? Move offset to the right and construct it at the same time
B
+f#f
OⓄ#MM
A
*
B
B
Of#f-+
|
+Ⓞ#M#MM
A
*
B
B
Of#f-+
|
+Ⓞ#M##MMM
A
bbb
|
+F
|
O ? Check and validate some important bytes, otherwise skip to the data section
I
I
I +-⁖-O ? Bits per pixel should be 24
# I I
I I I
+-M-+ #M# #--f-+
I $ B
I | S
+M+ #-+-#
[ ]
+⚠ EfB
o |
| ? Compression should be zero
#-+-#
[ ]
+⚠ +-f-B
o f-B
f-B
f-B
B
f-O ? Move offset value, subtract 34 from it
I
I
I +MD-+ +--------+
I I $ | B
I I S U B
#-+ +--⁖}--+ +4ff-+
| B ? Apply blue light filter
+-+-+ +-5ff-B
( ) B
| +-8ff-B
+F
|
+F
|
+R
U
+{---+
B |
+-+-+ |
( ) |
O-F +-f+
O ? Construct reserved part
O
O +-fff-+ +-fff-+
B B B B O
B B B B I
B B B B I
+-fff-+ +-fff-+ I
I
+-+ #--+ I
I I | I I
I I +b I I
I OfB | +-#
I +-MF I
+M+ I
|
+-O
|
OⓄO©DM#DDD##⦵DDD+
|
$
O---------------+
I
I
I
OⓄMDD+
$
+-©D#
I
#DDDDD#
I
I
I
I
#
I
#DDDDDDw-OD+
$
W
|
bmp.ec Unicode text, UTF-8 text
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113 | "utilities.ec"
"io.ec"
? Check signature
? Error and exit if signature does not match
+-⌂-O
| I+M#fB
| II S
| II #-+-#
++ II ] [
| II E +-⚠
E II +-+ o
| #+ +F
| +-b
| +⚠ A O
] [o * * I
#+# S I I
+---+ I I
+M#
? Check reserved
+-⛩-+
| |
| +-#-+
| [ ]
| +⚠ |
| o |
| +-#-+
| [ ]
| +⚠ |
| |o |
] [ +-#-+
+-+-+ ] [
#---+ +⚠
o
? Move N numbers to the next stack where N is the top-most item
+-⁖---+
| U
| +{--+
| | |
| #-+-# |
| ] [ |
+---E $ D
f-B
? Divide by 255
+-◲-+
| |
| +-OⓄ#MD-+
| $
+-----------Q
? Multiply by 255
+-⧉-OⓄ#MD
| |
+---M---+
? Gamma correction approximation
? x**2.2 ≈ max(0, -0.1099x+1.0989x**2)
+-γ-#O©+
| I +-MMDO©+
| I I I
| ##+ I
+{OE ###MMM+
n | |
l +L +-MMM### $
| | $ | +-M-Q
#-+-# Q +©+ $
S I I O-#
+-MM+ I |
OD+ +©+
S I
| I
+MM###
? Manipulate blue channel
+-8-◲-O
| I
+--+ I
| ##
| I
| ####M+
+γ⧉+ I
| I
| OMMMMM+
| I
| Q
| O
+--M+ I ? Multiply with magic constant, 2/9-1/1187. (Approximates 0.22137978)
S I
Q #
$ I
+M#
? Manipulate green channel
+-5-◲-O
| I +-+
+--+ I I $
| I I Q
| #-+ O
| +-ⓄDD#
+γ⧉+ D
| A D
+---M--* *Q D ? Multiply with magic constant, 3/5+1/138. (Approximates 0.60724493)
I D
ODDM-+
? Manipulate red channel, only do gamma correction
+-4--+
| |
+-◲γ⧉+
|
io.ec Unicode text, UTF-8 text
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62 | "utilities.ec"
? Print "Enter filename: "
+-⎚-O
| I +-P-O +-P-#
| I | I I D
+P+ I I I I D
| I A # I D
MM+ #-###MM I +-M-# I D
| I I | I D
+MM I | | I D
# +-M# #-P D-DDP-+
# I
# +MM### I
# | I +-P-+ I
I | I I D I
I S # I $ #-PO
| S I I +-P-# I
OP-+ I I I O#P+ +-+ I
O-P-+ I I | I I ####MMMMPDDDD#DDD
I I #PD-P I |
S I +----P# +-P#DDD#DD+
$ I | $
| | +-+
+-M-#
? Filename read loop, terminates if the input is equal to 0 (EOF)
+-⬟----+
| | +--+
+E U U |
| +++ |
+R | |
| &-+ |
| | [
| #-+-#
| ]
+{-E----+
? Print newline, useful for debugging
+-⏎-O
| I
| I
PM+ #
| I
I I
+-+
? Print "Invalid file"
+-+
| ⚠-O
| I #MMDD#P-O #MM+ A
| I I I I I * *
| I I I I I I #-P-##©P-ⓣ+
| #-+ #-+ I I I
| +P# +-+ I
+PM+ I I I
I I I I +PDDDP##DDP-+
I O-P+ I I |
I I DP+ +-#P# +⦵#PO
+-# I I
I I
+PMMMM####
|
lenna.bmp PC bitmap, Windows 98/2000 and newer format, 512 x 512 x 24, cbSize 786570, bits offset 138
utilities.ec Unicode text, UTF-8 text
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60 | ? Sign corrects the entire stack
? Pushes a -1 to the next stack first.
? Then goes back, loops through every item on the stack, adds 256 if the number is negative,
? and moves them to the next stack
? Finally moves everything back until it hits a -1 and pops it off
? Should work correctly if the stack contains bytes read from a file
? Otherwise you may end up in situations you wouldn't want to be in
+-⛁-FODO
| I
| I
| #######MMMMMMMB
| U
+{--------------+ +{-----+
| | |
+-+ E +-+-+ |
| [ ] ( ) |
| +-+-+ | #-+-# |
| # | | | |
| A EF +L | |
| * | | l |
| I | b#F | B
| O | A U $
F-}+b# | *--}+f-+
n |
+----+
? Add 8 to the number on top of the stack
*-©-O
\ I
\ I
\##MM+
\ |
\ A
**
? Add 16 to the number on top of the stack
*-Ⓞ-O
\ I
\ I
\###MMM*
\ A
*---*
? Subtract 8 from the number on top of the stack
*-⦵-O
\ I
\ I
\##MM+
\ $
\ S
*-+
? Subtract 16 from the number on top of the stack
*-ⓣ-O
\ I
\ I
\###MMM+
\ $
\ S
*---+
|
entry #9
comments 0
main.rs ASCII text
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499 | //! Takes sRGB PPM files as input
//! I know PPM isn't sRGB according to the spec
//! But even in the spec they mention putting sRGB data in
//! So fuck the spec it assumes sRGB
//! Usage: input output [target temperature] [source temperature]
//! Default target is 4000K, default source is 6500K
//! Temperatures are in Kelvin
//! Not much output apart from that. It's a tad slow but does its job.
use std::env::Args;
use std::error::Error;
use std::fs::File;
use std::io;
use std::io::BufReader;
use std::io::BufWriter;
use std::io::ErrorKind;
use std::io::prelude::*;
use std::path::Path;
use std::str::FromStr;
/// Second radiation constant
/// Source: https://en.wikipedia.org/wiki/Planckian_locus#International_Temperature_Scale
const C_2: f64 = 1.438_776_877;
/// Adapting luminance
/// https://en.wikipedia.org/wiki/CIECAM02#Parameter_decision_table
/// https://en.wikipedia.org/wiki/SRGB#Viewing_environment
const L_A: f64 = 0.20 * 80.;
/// Surround factor
const F: f64 = 1.;
#[derive(Debug)]
enum PPMRaster {
PPM8(Vec<Vec<(u8, u8, u8)>>),
PPM16(Vec<Vec<(u16, u16, u16)>>),
}
#[derive(Debug)]
struct PPM {
width: usize,
height: usize,
maxval: u16,
raster: PPMRaster,
}
impl PPM {
fn write(&self, mut file: File) -> Result<(), io::Error> {
file.write_all(&['P' as u8, '6' as u8, '\n' as u8])?;
file.write_all(self.width.to_string().as_bytes())?;
file.write_all(&[' ' as u8])?;
file.write_all(self.height.to_string().as_bytes())?;
file.write_all(&['\n' as u8])?;
file.write_all(self.maxval.to_string().as_bytes())?;
file.write_all(&['\n' as u8])?;
let mut handle: BufWriter<File> = BufWriter::with_capacity(
match self.maxval {
0..256 => self.width * 3,
_ => self.width * 6,
},
file,
);
for row in 0..self.height {
for column in 0..self.width {
match &self.raster {
PPMRaster::PPM8(pixels) => {
handle.write_all(&[
pixels[row][column].0,
pixels[row][column].1,
pixels[row][column].2,
])?;
}
PPMRaster::PPM16(pixels) => {
handle.write_all(&pixels[row][column].0.to_be_bytes())?;
handle.write_all(&pixels[row][column].1.to_be_bytes())?;
handle.write_all(&pixels[row][column].2.to_be_bytes())?;
}
}
}
}
handle.flush()?;
Ok(())
}
fn read(mut file: File) -> Result<PPM, Box<dyn Error>> {
fn read_line(file: &mut File) -> Result<Vec<char>, io::Error> {
let mut buf: Vec<char> = Vec::new();
loop {
let mut byte: [u8; 1] = Default::default();
file.read_exact(&mut byte)?;
let chr: char = byte[0] as char;
match chr {
'#' => {
while (byte[0] as char) != '\r' && (byte[0] as char) != '\n' {
match file.read_exact(&mut byte) {
Ok(_) => {}
Err(why) => match why.kind() {
ErrorKind::UnexpectedEof => {
return Ok(buf);
}
_ => {
return Err(why);
}
},
}
}
}
'\t' | '\r' | '\n' | ' ' | '\x0b' | '\x0c' => {
return Ok(buf);
}
_ => {
buf.push(chr);
}
}
}
}
fn parse_number<N: FromStr>(v: Vec<char>) -> Result<N, <N as FromStr>::Err> {
v.into_iter().collect::<String>().parse::<N>()
}
let magic_number: Vec<char> = read_line(&mut file)?;
if magic_number != vec!['P', '6'] {
return Err(format!(
"This program only supports PPM files! (magic number = {:?})",
magic_number
)
.into());
}
let width: usize = parse_number(read_line(&mut file)?)?;
let height: usize = parse_number(read_line(&mut file)?)?;
let maxval: u16 = parse_number(read_line(&mut file)?)?;
let mut raster: PPMRaster;
if maxval < 256 {
raster = PPMRaster::PPM8(Vec::with_capacity(height));
} else {
raster = PPMRaster::PPM16(Vec::with_capacity(height));
}
let mut handle: BufReader<File> = match raster {
PPMRaster::PPM8(_) => BufReader::with_capacity(width * 3, file),
PPMRaster::PPM16(_) => BufReader::with_capacity(width * 6, file),
};
for row in 0..height {
match raster {
PPMRaster::PPM8(ref mut v) => v.push(Vec::with_capacity(width)),
PPMRaster::PPM16(ref mut v) => v.push(Vec::with_capacity(width)),
}
for _ in 0..width {
match raster {
PPMRaster::PPM8(ref mut v) => {
let mut buf: [u8; 3] = Default::default();
handle.read_exact(&mut buf)?;
v[row].push((buf[0], buf[1], buf[2]));
}
PPMRaster::PPM16(ref mut v) => {
let mut buf: [u8; 6] = Default::default();
handle.read_exact(&mut buf)?;
fn to_u16(a: u8, b: u8) -> u16 {
((a as u16) << 8) | (b as u16)
}
v[row].push((
to_u16(buf[0], buf[1]),
to_u16(buf[2], buf[3]),
to_u16(buf[4], buf[5]),
));
}
}
}
}
Ok(PPM {
width,
height,
maxval,
raster,
})
}
}
impl From<&PPM> for Raster<SRgb> {
fn from(value: &PPM) -> Self {
let mut floats: Vec<Vec<SRgb>>;
match &value.raster {
PPMRaster::PPM8(v) => {
floats = Vec::with_capacity(v.len());
for row in 0..v.len() {
floats.push(Vec::with_capacity(v[row].len()));
for pixel in 0..v[row].len() {
floats[row].push(SRgb::from((
f64::from(v[row][pixel].0) / (value.maxval as f64),
f64::from(v[row][pixel].1) / (value.maxval as f64),
f64::from(v[row][pixel].2) / (value.maxval as f64),
)));
}
}
}
PPMRaster::PPM16(v) => {
floats = Vec::with_capacity(v.len());
for row in 0..v.len() {
floats.push(Vec::with_capacity(v[row].len()));
for pixel in 0..v[row].len() {
floats[row].push(SRgb::from((
f64::from(v[row][pixel].0) / (value.maxval as f64),
f64::from(v[row][pixel].1) / (value.maxval as f64),
f64::from(v[row][pixel].2) / (value.maxval as f64),
)));
}
}
}
}
Self(floats)
}
}
impl From<(&Raster<SRgb>, u16)> for PPM {
fn from(value: (&Raster<SRgb>, u16)) -> Self {
let floats: &Vec<Vec<SRgb>> = &value.0.0;
let maxval: u16 = value.1;
PPM {
width: floats[0].len(),
height: floats.len(),
maxval,
raster: match maxval {
0..256 => {
let mut integers: Vec<Vec<(u8, u8, u8)>> = Vec::with_capacity(floats.len());
for row in 0..floats.len() {
integers.push(Vec::with_capacity(floats[row].len()));
for pixel in 0..floats[row].len() {
integers[row].push((
(floats[row][pixel].r * (maxval as f64)).round() as u8,
(floats[row][pixel].g * (maxval as f64)).round() as u8,
(floats[row][pixel].b * (maxval as f64)).round() as u8,
));
}
}
PPMRaster::PPM8(integers)
}
_ => {
let mut integers: Vec<Vec<(u16, u16, u16)>> = Vec::with_capacity(floats.len());
for row in 0..floats.len() {
integers.push(Vec::with_capacity(floats[row].len()));
for pixel in 0..floats[row].len() {
integers[row].push((
(floats[row][pixel].r * (maxval as f64)).round() as u16,
(floats[row][pixel].g * (maxval as f64)).round() as u16,
(floats[row][pixel].b * (maxval as f64)).round() as u16,
));
}
}
PPMRaster::PPM16(integers)
}
},
}
}
}
macro_rules! color {
($color_space:ident { $first_component:ident , $second_component:ident , $third_component:ident }) => {
#[derive(Debug, Clone, Copy)]
struct $color_space {
$first_component: f64,
$second_component: f64,
$third_component: f64,
}
impl From<$color_space> for (f64, f64, f64) {
fn from(value: $color_space) -> Self {
(
value.$first_component,
value.$second_component,
value.$third_component,
)
}
}
impl From<(f64, f64, f64)> for $color_space {
fn from(value: (f64, f64, f64)) -> Self {
Self {
$first_component: value.0,
$second_component: value.1,
$third_component: value.2,
}
}
}
};
}
color! {Xyz { x, y, z }}
color! {Rgb { r, g, b }}
color! {SRgb { r, g, b }}
color! {Lms { l, m, s }}
#[derive(Debug)]
struct Raster<C>(Vec<Vec<C>>);
impl<C> Raster<C> {
fn apply<I, F: Fn(&C) -> I>(&self, function: F) -> Raster<I> {
Raster(
self.0
.iter()
.map(|row| row.iter().map(|pixel| function(pixel)).collect())
.collect(),
)
}
fn convert<I: for<'a> From<&'a C>>(&self) -> Raster<I> {
self.apply(|pixel| pixel.into())
}
}
/// https://en.wikipedia.org/wiki/SRGB#Transfer_function_(%22gamma%22)
impl From<&SRgb> for Rgb {
fn from(value: &SRgb) -> Self {
fn transfer(channel: f64) -> f64 {
if channel <= 0.04045 {
channel / 12.92
} else {
((channel + 0.055) / 1.055).powf(2.4)
}
}
Self {
r: transfer(value.r),
g: transfer(value.g),
b: transfer(value.b),
}
}
}
/// https://en.wikipedia.org/wiki/SRGB#Transfer_function_(%22gamma%22)
impl From<&Rgb> for SRgb {
fn from(value: &Rgb) -> Self {
fn inverse_transfer(channel: f64) -> f64 {
if channel < 0. {
-inverse_transfer(-channel)
} else if channel <= 0.0031308 {
12.92 * channel
} else {
1.055 * channel.powf(1. / 2.4) - 0.055
}
}
Self {
r: inverse_transfer(value.r),
g: inverse_transfer(value.g),
b: inverse_transfer(value.b),
}
}
}
impl From<&Rgb> for Xyz {
fn from(value: &Rgb) -> Self {
Self {
x: 0.4124 * value.r + 0.3576 * value.g + 0.1805 * value.b,
y: 0.2126 * value.r + 0.7152 * value.g + 0.0722 * value.b,
z: 0.0193 * value.r + 0.1192 * value.g + 0.9505 * value.b,
}
}
}
impl From<&Xyz> for Lms {
fn from(value: &Xyz) -> Self {
Self {
l: 0.4002 * value.x + 0.7076 * value.y + -0.0808 * value.z,
m: -0.2263 * value.x + 1.1653 * value.y + 0.0457 * value.z,
s: 0.9182 * value.z,
}
}
}
impl From<&Lms> for Rgb {
fn from(value: &Lms) -> Self {
Self {
r: 5.47250449 * value.l + -4.64219699 * value.m + 0.16956890 * value.s,
g: -1.12470958 * value.l + 2.29262899 * value.m + -0.16786338 * value.s,
b: 0.02992745 * value.l + -0.19325300 * value.m + 1.16341292 * value.s,
}
}
}
fn chromatic_adaption(pixel: &Lms, source: &Lms, target: &Lms) -> Lms {
let d: f64 = F * (1. - (1. / 3.6) * f64::exp((-L_A - 42.) / 92.));
Lms {
l: ((target.l / source.l) * d + 1. - d) * pixel.l,
m: ((target.m / source.m) * d + 1. - d) * pixel.m,
s: ((target.s / source.s) * d + 1. - d) * pixel.s,
}
}
/// Perform chromatic adaption on an LMS image
/// Takes source and target illuminants in LMS form as inputs
/// https://en.wikipedia.org/wiki/CIECAM02#CAT02
fn chromatic_adaption_raster(lms: &Raster<Lms>, source: &Lms, target: &Lms) -> Raster<Lms> {
lms.apply(|pixel| chromatic_adaption(pixel, source, target))
}
/// Compute LMS coordinates coordinate of the D illuminant of the given temperature (in K)
/// Color temperature is rectified (e.g. 6500K -> 6503.51K).
/// Standard value of 1 for Y is used
fn standard_illuminant_d(temperature: f64) -> Result<Lms, &'static str> {
// Adjust temperature (you know, Planck's constant sometime changes)
let t: f64 = temperature * (C_2 / 1.4380);
// Compute xy (CIE 1931) coordinates of the illuminant
let x_d: f64;
if temperature < 1667. {
return Err("No D illuminant below 1667K.");
} else if temperature <= 4000. {
// /!\ Planckian locus approximation
x_d = -0.2661239 * (1e9 / t.powf(3.)) - 0.2343589 * (1e6 / t.powf(2.))
+ 0.8776956 * (1e3 / t)
+ 0.179910
} else if temperature <= 7000. {
x_d = 0.244063 + (0.09911 * (1e3 / t)) + (2.9678 * (1e6 / t.powf(2.)))
- (4.6070 * (1e9 / t.powf(3.)));
} else if temperature <= 25000. {
x_d = 0.237040 + (0.24748 * (1e3 / t)) + (1.9018 * (1e6 / t.powf(2.)))
- (2.0064 * (1e9 / t.powf(3.)));
} else {
return Err("No D illuminant above 25000K");
}
let y_d: f64;
if temperature <= 2222. {
y_d = -1.1063814 * x_d.powf(3.) - 1.34811020 * x_d.powf(2.) + 2.18555832 * x_d - 0.20219683
} else if temperature <= 4000. {
y_d = -0.9549476 * x_d.powf(3.) - 1.37418593 * x_d.powf(2.) + 2.09137015 * x_d - 0.16748867;
} else {
y_d = (-3.000 * (x_d.powf(2.))) + (2.870 * x_d) - 0.275;
}
// Assuming Y = 1, convert xy (to xyY) to XYZ
let xyz: Xyz = Xyz {
x: (1. / y_d) * x_d,
y: 1.,
z: (1. / y_d) * (1. - x_d - y_d),
};
// Convert to LMS
let lms: Lms = Lms::from(&xyz);
Ok(lms)
}
fn main() -> Result<(), Box<dyn Error>> {
let mut args: Args = std::env::args();
args.next();
let input_path: &str = &args
.next()
.ok_or("First argument must be the path to the input file")?;
let output_path: &str = &args
.next()
.ok_or("Second argument must be the path to the output file")?;
// Target color temperature
let target_illuminant: Lms = standard_illuminant_d(
args.next()
.map(|temperature| temperature.parse::<f64>().unwrap_or(4000.))
.unwrap_or(4000.),
)?;
// sRGB encoding illuminant
let source_illuminant: Lms = standard_illuminant_d(
args.next()
.map(|temperature| temperature.parse::<f64>().unwrap_or(6500.))
.unwrap_or(6500.),
)?;
let path: &Path = Path::new(input_path);
let file: File = File::open(&path)?;
let ppm: PPM = PPM::read(file)?;
let s_rgb_raster: Raster<SRgb> = Raster::from(&ppm);
// Multiple functions version
// Caution: memory intensive!
/*
let rgb_raster: Raster<Rgb> = s_rgb_raster.convert::<Rgb>();
let xyz_raster: Raster<Xyz> = rgb_raster.convert::<Xyz>();
let lms_raster: Raster<Lms> = xyz_raster.convert::<Lms>();
let lms_raster_adapt: Raster<Lms> =
chromatic_adaption_raster(&lms_raster, &source_illuminant, &target_illuminant);
let rgb_raster_adapt: Raster<Rgb> = lms_raster_adapt.convert::<Rgb>();
let s_rgb_raster_adapt: Raster<SRgb> = rgb_raster_adapt.convert::<SRgb>();
*/
// Single function version
let s_rgb_raster_adapt: Raster<SRgb> = s_rgb_raster.apply(|pixel| {
SRgb::from(&Rgb::from(&chromatic_adaption(
&Lms::from(&Xyz::from(&Rgb::from(pixel))),
&source_illuminant,
&target_illuminant,
)))
});
let output: PPM = PPM::from((&s_rgb_raster_adapt, ppm.maxval));
output.write(File::create(Path::new(output_path))?)?;
Ok(())
}
|
is this #0000ff
yes it is!
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