Crate rawloader

Library to extract the raw data and some metadata from digital camera images. Given an image in a supported format and camera you will be able to get everything needed to process the image

Example

use std::env;
use std::fs::File;
use std::io::prelude::*;
use std::io::BufWriter;

extern crate rawloader;

fn main() {
  let args: Vec<_> = env::args().collect();
  if args.len() != 2 {
    println!("Usage: {} <file>", args[0]);
    std::process::exit(2);
  }
  let file = &args[1];
  let image = rawloader::decode(file).unwrap();

  // Write out the image as a grayscale PPM
  let mut f = BufWriter::new(File::create(format!("{}.ppm",file)).unwrap());
  let preamble = format!("P6 {} {} {}\n", image.width, image.height, 65535).into_bytes();
  f.write_all(&preamble).unwrap();
  for pix in image.data {
    // Do an extremely crude "demosaic" by setting R=G=B
    let pixhigh = (pix>>8) as u8;
    let pixlow  = (pix&0x0f) as u8;
    f.write_all(&[pixhigh, pixlow, pixhigh, pixlow, pixhigh, pixlow]).unwrap()
  }
}

To do the image decoding decode the image the same way but then do:

// Decode to the largest image that fits in 1080p size. If the original image is
// smaller this will not scale up but otherwise you will get an image that is either
// 1920 pixels wide or 1080 pixels tall and maintains the image ratio.
let decoded = image.to_rgb(1920, 1080).unwrap();

let mut f = BufWriter::new(File::create(format!("{}.ppm",file)).unwrap());
let preamble = format!("P6 {} {} {}\n", decoded.width, decoded.height, 255).into_bytes();
f.write_all(&preamble).unwrap();
for pix in decoded.data {
  let pixel = ((pix.max(0.0)*255.0).min(255.0)) as u8;
  f.write_all(&[pixel]).unwrap();
}

This is useful as a reference output and if all you need is a thumbnail or a preview it will be a decent output that is produced fast (200-300ms for a 500x500 thumbnail of a 24MP image).

Structs

CFA	Representation of the color filter array pattern in raw cameras
RGBImage	A RawImage processed into a full RGB image with levels and gamma
RawImage	All the data needed to process this raw image, including the image data itself as well as all the needed metadata
SRGBImage	A RawImage processed into a full 8bit sRGB image with levels and gamma

Functions

decode

Take a path to a raw file and return a decoded image or an error