71 lines
2.5 KiB
Rust
71 lines
2.5 KiB
Rust
|
|
extern crate image as png;
|
|
use std::cmp::Ordering;
|
|
|
|
extern crate exr;
|
|
|
|
|
|
pub fn main() {
|
|
use exr::prelude::*;
|
|
|
|
let path = "tests/images/valid/openexr/MultiResolution/Kapaa.exr";
|
|
let now = ::std::time::Instant::now();
|
|
|
|
// load the exr file from disk with multi-core decompression
|
|
let image = read_all_data_from_file(path).unwrap();
|
|
|
|
// warning: highly unscientific benchmarks ahead!
|
|
println!("\nloaded file in {:?}s", now.elapsed().as_secs_f32());
|
|
println!("writing images...");
|
|
|
|
for (layer_index, layer) in image.layer_data.iter().enumerate() {
|
|
let layer_name = layer.attributes.layer_name.as_ref()
|
|
.map_or(String::from("1"), Text::to_string);
|
|
|
|
for channel in &layer.channel_data.list {
|
|
for (level, level_size) in layer.levels_with_resolution(&channel.sample_data) {
|
|
let data : Vec<f32> = level.values_as_f32().collect();
|
|
|
|
save_f32_image_as_png(&data, level_size, format!(
|
|
"tests/images/out/{} ({}) {}.{}x{}.png",
|
|
layer_index, layer_name, channel.name,
|
|
level_size.width(), level_size.height(),
|
|
))
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Save raw float data to a PNG file, doing automatic brightness adjustments per channel
|
|
fn save_f32_image_as_png(data: &[f32], size: Vec2<usize>, name: String) {
|
|
let mut png_buffer = png::GrayImage::new(size.width() as u32, size.height() as u32);
|
|
let mut sorted = Vec::from(data);
|
|
sorted.sort_by(|a, b| a.partial_cmp(b).unwrap_or(Ordering::Less));
|
|
|
|
// percentile normalization
|
|
let max = sorted[7 * sorted.len() / 8];
|
|
let min = sorted[1 * sorted.len() / 8];
|
|
|
|
// primitive tone mapping
|
|
let tone = |v: f32| (v - 0.5).tanh() * 0.5 + 0.5;
|
|
let max_toned = tone(*sorted.last().unwrap());
|
|
let min_toned = tone(*sorted.first().unwrap());
|
|
|
|
// for each pixel, tone map the value
|
|
for (x, y, pixel) in png_buffer.enumerate_pixels_mut() {
|
|
let v = data[(y as usize * size.0 + x as usize)];
|
|
let v = (v - min) / (max - min);
|
|
let v = tone(v);
|
|
|
|
let v = (v - min_toned) / (max_toned - min_toned);
|
|
|
|
// TODO does the `image` crate expect gamma corrected data?
|
|
*pixel = png::Luma([(v.max(0.0).min(1.0) * 255.0) as u8]);
|
|
}
|
|
|
|
png_buffer.save(&name).unwrap();
|
|
}
|
|
|
|
println!("created all images");
|
|
}
|
|
|