imgview

readme.md

Imgview

Clone this, get cargo and run cargo build --release. Then ./target/release/imgview /path/to/image will render images ✨

Cargo.toml

[package]
name = "imgview"
version = "0.1.0"

[[bin]]
name = "imgview"
path = "main.rs"

[dependencies]
clap = "2.24.2"
image = "0.13.0"
term = "0.4.5"
term_size = "0.3.0"

colors.rs

pub struct Color {
    pub r: u8,
    pub g: u8,
    pub b: u8,
}

pub const COLORS: [Color; 256] = [
    Color { r: 0x00, g: 0x00, b: 0x00 },
    Color { r: 0x80, g: 0x00, b: 0x00 },
    Color { r: 0x00, g: 0x80, b: 0x00 },
    Color { r: 0x80, g: 0x80, b: 0x00 },
    Color { r: 0x00, g: 0x00, b: 0x80 },
    Color { r: 0x80, g: 0x00, b: 0x80 },
    Color { r: 0x00, g: 0x80, b: 0x80 },
    Color { r: 0xc0, g: 0xc0, b: 0xc0 },
    Color { r: 0x80, g: 0x80, b: 0x80 },
    Color { r: 0xff, g: 0x00, b: 0x00 },
    Color { r: 0x00, g: 0xff, b: 0x00 },
    Color { r: 0xff, g: 0xff, b: 0x00 },
    Color { r: 0x00, g: 0x00, b: 0xff },
    Color { r: 0xff, g: 0x00, b: 0xff },
    Color { r: 0x00, g: 0xff, b: 0xff },
    Color { r: 0xff, g: 0xff, b: 0xff },
    Color { r: 0x00, g: 0x00, b: 0x00 },
    Color { r: 0x00, g: 0x00, b: 0x5f },
    Color { r: 0x00, g: 0x00, b: 0x87 },
    Color { r: 0x00, g: 0x00, b: 0xaf },
    Color { r: 0x00, g: 0x00, b: 0xd7 },
    Color { r: 0x00, g: 0x00, b: 0xff },
    Color { r: 0x00, g: 0x5f, b: 0x00 },
    Color { r: 0x00, g: 0x5f, b: 0x5f },
    Color { r: 0x00, g: 0x5f, b: 0x87 },
    Color { r: 0x00, g: 0x5f, b: 0xaf },
    Color { r: 0x00, g: 0x5f, b: 0xd7 },
    Color { r: 0x00, g: 0x5f, b: 0xff },
    Color { r: 0x00, g: 0x87, b: 0x00 },
    Color { r: 0x00, g: 0x87, b: 0x5f },
    Color { r: 0x00, g: 0x87, b: 0x87 },
    Color { r: 0x00, g: 0x87, b: 0xaf },
    Color { r: 0x00, g: 0x87, b: 0xd7 },
    Color { r: 0x00, g: 0x87, b: 0xff },
    Color { r: 0x00, g: 0xaf, b: 0x00 },
    Color { r: 0x00, g: 0xaf, b: 0x5f },
    Color { r: 0x00, g: 0xaf, b: 0x87 },
    Color { r: 0x00, g: 0xaf, b: 0xaf },
    Color { r: 0x00, g: 0xaf, b: 0xd7 },
    Color { r: 0x00, g: 0xaf, b: 0xff },
    Color { r: 0x00, g: 0xd7, b: 0x00 },
    Color { r: 0x00, g: 0xd7, b: 0x5f },
    Color { r: 0x00, g: 0xd7, b: 0x87 },
    Color { r: 0x00, g: 0xd7, b: 0xaf },
    Color { r: 0x00, g: 0xd7, b: 0xd7 },
    Color { r: 0x00, g: 0xd7, b: 0xff },
    Color { r: 0x00, g: 0xff, b: 0x00 },
    Color { r: 0x00, g: 0xff, b: 0x5f },
    Color { r: 0x00, g: 0xff, b: 0x87 },
    Color { r: 0x00, g: 0xff, b: 0xaf },
    Color { r: 0x00, g: 0xff, b: 0xd7 },
    Color { r: 0x00, g: 0xff, b: 0xff },
    Color { r: 0x5f, g: 0x00, b: 0x00 },
    Color { r: 0x5f, g: 0x00, b: 0x5f },
    Color { r: 0x5f, g: 0x00, b: 0x87 },
    Color { r: 0x5f, g: 0x00, b: 0xaf },
    Color { r: 0x5f, g: 0x00, b: 0xd7 },
    Color { r: 0x5f, g: 0x00, b: 0xff },
    Color { r: 0x5f, g: 0x5f, b: 0x00 },
    Color { r: 0x5f, g: 0x5f, b: 0x5f },
    Color { r: 0x5f, g: 0x5f, b: 0x87 },
    Color { r: 0x5f, g: 0x5f, b: 0xaf },
    Color { r: 0x5f, g: 0x5f, b: 0xd7 },
    Color { r: 0x5f, g: 0x5f, b: 0xff },
    Color { r: 0x5f, g: 0x87, b: 0x00 },
    Color { r: 0x5f, g: 0x87, b: 0x5f },
    Color { r: 0x5f, g: 0x87, b: 0x87 },
    Color { r: 0x5f, g: 0x87, b: 0xaf },
    Color { r: 0x5f, g: 0x87, b: 0xd7 },
    Color { r: 0x5f, g: 0x87, b: 0xff },
    Color { r: 0x5f, g: 0xaf, b: 0x00 },
    Color { r: 0x5f, g: 0xaf, b: 0x5f },
    Color { r: 0x5f, g: 0xaf, b: 0x87 },
    Color { r: 0x5f, g: 0xaf, b: 0xaf },
    Color { r: 0x5f, g: 0xaf, b: 0xd7 },
    Color { r: 0x5f, g: 0xaf, b: 0xff },
    Color { r: 0x5f, g: 0xd7, b: 0x00 },
    Color { r: 0x5f, g: 0xd7, b: 0x5f },
    Color { r: 0x5f, g: 0xd7, b: 0x87 },
    Color { r: 0x5f, g: 0xd7, b: 0xaf },
    Color { r: 0x5f, g: 0xd7, b: 0xd7 },
    Color { r: 0x5f, g: 0xd7, b: 0xff },
    Color { r: 0x5f, g: 0xff, b: 0x00 },
    Color { r: 0x5f, g: 0xff, b: 0x5f },
    Color { r: 0x5f, g: 0xff, b: 0x87 },
    Color { r: 0x5f, g: 0xff, b: 0xaf },
    Color { r: 0x5f, g: 0xff, b: 0xd7 },
    Color { r: 0x5f, g: 0xff, b: 0xff },
    Color { r: 0x87, g: 0x00, b: 0x00 },
    Color { r: 0x87, g: 0x00, b: 0x5f },
    Color { r: 0x87, g: 0x00, b: 0x87 },
    Color { r: 0x87, g: 0x00, b: 0xaf },
    Color { r: 0x87, g: 0x00, b: 0xd7 },
    Color { r: 0x87, g: 0x00, b: 0xff },
    Color { r: 0x87, g: 0x5f, b: 0x00 },
    Color { r: 0x87, g: 0x5f, b: 0x5f },
    Color { r: 0x87, g: 0x5f, b: 0x87 },
    Color { r: 0x87, g: 0x5f, b: 0xaf },
    Color { r: 0x87, g: 0x5f, b: 0xd7 },
    Color { r: 0x87, g: 0x5f, b: 0xff },
    Color { r: 0x87, g: 0x87, b: 0x00 },
    Color { r: 0x87, g: 0x87, b: 0x5f },
    Color { r: 0x87, g: 0x87, b: 0x87 },
    Color { r: 0x87, g: 0x87, b: 0xaf },
    Color { r: 0x87, g: 0x87, b: 0xd7 },
    Color { r: 0x87, g: 0x87, b: 0xff },
    Color { r: 0x87, g: 0xaf, b: 0x00 },
    Color { r: 0x87, g: 0xaf, b: 0x5f },
    Color { r: 0x87, g: 0xaf, b: 0x87 },
    Color { r: 0x87, g: 0xaf, b: 0xaf },
    Color { r: 0x87, g: 0xaf, b: 0xd7 },
    Color { r: 0x87, g: 0xaf, b: 0xff },
    Color { r: 0x87, g: 0xd7, b: 0x00 },
    Color { r: 0x87, g: 0xd7, b: 0x5f },
    Color { r: 0x87, g: 0xd7, b: 0x87 },
    Color { r: 0x87, g: 0xd7, b: 0xaf },
    Color { r: 0x87, g: 0xd7, b: 0xd7 },
    Color { r: 0x87, g: 0xd7, b: 0xff },
    Color { r: 0x87, g: 0xff, b: 0x00 },
    Color { r: 0x87, g: 0xff, b: 0x5f },
    Color { r: 0x87, g: 0xff, b: 0x87 },
    Color { r: 0x87, g: 0xff, b: 0xaf },
    Color { r: 0x87, g: 0xff, b: 0xd7 },
    Color { r: 0x87, g: 0xff, b: 0xff },
    Color { r: 0xaf, g: 0x00, b: 0x00 },
    Color { r: 0xaf, g: 0x00, b: 0x5f },
    Color { r: 0xaf, g: 0x00, b: 0x87 },
    Color { r: 0xaf, g: 0x00, b: 0xaf },
    Color { r: 0xaf, g: 0x00, b: 0xd7 },
    Color { r: 0xaf, g: 0x00, b: 0xff },
    Color { r: 0xaf, g: 0x5f, b: 0x00 },
    Color { r: 0xaf, g: 0x5f, b: 0x5f },
    Color { r: 0xaf, g: 0x5f, b: 0x87 },
    Color { r: 0xaf, g: 0x5f, b: 0xaf },
    Color { r: 0xaf, g: 0x5f, b: 0xd7 },
    Color { r: 0xaf, g: 0x5f, b: 0xff },
    Color { r: 0xaf, g: 0x87, b: 0x00 },
    Color { r: 0xaf, g: 0x87, b: 0x5f },
    Color { r: 0xaf, g: 0x87, b: 0x87 },
    Color { r: 0xaf, g: 0x87, b: 0xaf },
    Color { r: 0xaf, g: 0x87, b: 0xd7 },
    Color { r: 0xaf, g: 0x87, b: 0xff },
    Color { r: 0xaf, g: 0xaf, b: 0x00 },
    Color { r: 0xaf, g: 0xaf, b: 0x5f },
    Color { r: 0xaf, g: 0xaf, b: 0x87 },
    Color { r: 0xaf, g: 0xaf, b: 0xaf },
    Color { r: 0xaf, g: 0xaf, b: 0xd7 },
    Color { r: 0xaf, g: 0xaf, b: 0xff },
    Color { r: 0xaf, g: 0xd7, b: 0x00 },
    Color { r: 0xaf, g: 0xd7, b: 0x5f },
    Color { r: 0xaf, g: 0xd7, b: 0x87 },
    Color { r: 0xaf, g: 0xd7, b: 0xaf },
    Color { r: 0xaf, g: 0xd7, b: 0xd7 },
    Color { r: 0xaf, g: 0xd7, b: 0xff },
    Color { r: 0xaf, g: 0xff, b: 0x00 },
    Color { r: 0xaf, g: 0xff, b: 0x5f },
    Color { r: 0xaf, g: 0xff, b: 0x87 },
    Color { r: 0xaf, g: 0xff, b: 0xaf },
    Color { r: 0xaf, g: 0xff, b: 0xd7 },
    Color { r: 0xaf, g: 0xff, b: 0xff },
    Color { r: 0xd7, g: 0x00, b: 0x00 },
    Color { r: 0xd7, g: 0x00, b: 0x5f },
    Color { r: 0xd7, g: 0x00, b: 0x87 },
    Color { r: 0xd7, g: 0x00, b: 0xaf },
    Color { r: 0xd7, g: 0x00, b: 0xd7 },
    Color { r: 0xd7, g: 0x00, b: 0xff },
    Color { r: 0xd7, g: 0x5f, b: 0x00 },
    Color { r: 0xd7, g: 0x5f, b: 0x5f },
    Color { r: 0xd7, g: 0x5f, b: 0x87 },
    Color { r: 0xd7, g: 0x5f, b: 0xaf },
    Color { r: 0xd7, g: 0x5f, b: 0xd7 },
    Color { r: 0xd7, g: 0x5f, b: 0xff },
    Color { r: 0xd7, g: 0x87, b: 0x00 },
    Color { r: 0xd7, g: 0x87, b: 0x5f },
    Color { r: 0xd7, g: 0x87, b: 0x87 },
    Color { r: 0xd7, g: 0x87, b: 0xaf },
    Color { r: 0xd7, g: 0x87, b: 0xd7 },
    Color { r: 0xd7, g: 0x87, b: 0xff },
    Color { r: 0xd7, g: 0xaf, b: 0x00 },
    Color { r: 0xd7, g: 0xaf, b: 0x5f },
    Color { r: 0xd7, g: 0xaf, b: 0x87 },
    Color { r: 0xd7, g: 0xaf, b: 0xaf },
    Color { r: 0xd7, g: 0xaf, b: 0xd7 },
    Color { r: 0xd7, g: 0xaf, b: 0xff },
    Color { r: 0xd7, g: 0xd7, b: 0x00 },
    Color { r: 0xd7, g: 0xd7, b: 0x5f },
    Color { r: 0xd7, g: 0xd7, b: 0x87 },
    Color { r: 0xd7, g: 0xd7, b: 0xaf },
    Color { r: 0xd7, g: 0xd7, b: 0xd7 },
    Color { r: 0xd7, g: 0xd7, b: 0xff },
    Color { r: 0xd7, g: 0xff, b: 0x00 },
    Color { r: 0xd7, g: 0xff, b: 0x5f },
    Color { r: 0xd7, g: 0xff, b: 0x87 },
    Color { r: 0xd7, g: 0xff, b: 0xaf },
    Color { r: 0xd7, g: 0xff, b: 0xd7 },
    Color { r: 0xd7, g: 0xff, b: 0xff },
    Color { r: 0xff, g: 0x00, b: 0x00 },
    Color { r: 0xff, g: 0x00, b: 0x5f },
    Color { r: 0xff, g: 0x00, b: 0x87 },
    Color { r: 0xff, g: 0x00, b: 0xaf },
    Color { r: 0xff, g: 0x00, b: 0xd7 },
    Color { r: 0xff, g: 0x00, b: 0xff },
    Color { r: 0xff, g: 0x5f, b: 0x00 },
    Color { r: 0xff, g: 0x5f, b: 0x5f },
    Color { r: 0xff, g: 0x5f, b: 0x87 },
    Color { r: 0xff, g: 0x5f, b: 0xaf },
    Color { r: 0xff, g: 0x5f, b: 0xd7 },
    Color { r: 0xff, g: 0x5f, b: 0xff },
    Color { r: 0xff, g: 0x87, b: 0x00 },
    Color { r: 0xff, g: 0x87, b: 0x5f },
    Color { r: 0xff, g: 0x87, b: 0x87 },
    Color { r: 0xff, g: 0x87, b: 0xaf },
    Color { r: 0xff, g: 0x87, b: 0xd7 },
    Color { r: 0xff, g: 0x87, b: 0xff },
    Color { r: 0xff, g: 0xaf, b: 0x00 },
    Color { r: 0xff, g: 0xaf, b: 0x5f },
    Color { r: 0xff, g: 0xaf, b: 0x87 },
    Color { r: 0xff, g: 0xaf, b: 0xaf },
    Color { r: 0xff, g: 0xaf, b: 0xd7 },
    Color { r: 0xff, g: 0xaf, b: 0xff },
    Color { r: 0xff, g: 0xd7, b: 0x00 },
    Color { r: 0xff, g: 0xd7, b: 0x5f },
    Color { r: 0xff, g: 0xd7, b: 0x87 },
    Color { r: 0xff, g: 0xd7, b: 0xaf },
    Color { r: 0xff, g: 0xd7, b: 0xd7 },
    Color { r: 0xff, g: 0xd7, b: 0xff },
    Color { r: 0xff, g: 0xff, b: 0x00 },
    Color { r: 0xff, g: 0xff, b: 0x5f },
    Color { r: 0xff, g: 0xff, b: 0x87 },
    Color { r: 0xff, g: 0xff, b: 0xaf },
    Color { r: 0xff, g: 0xff, b: 0xd7 },
    Color { r: 0xff, g: 0xff, b: 0xff },
    Color { r: 0x08, g: 0x08, b: 0x08 },
    Color { r: 0x12, g: 0x12, b: 0x12 },
    Color { r: 0x1c, g: 0x1c, b: 0x1c },
    Color { r: 0x26, g: 0x26, b: 0x26 },
    Color { r: 0x30, g: 0x30, b: 0x30 },
    Color { r: 0x3a, g: 0x3a, b: 0x3a },
    Color { r: 0x44, g: 0x44, b: 0x44 },
    Color { r: 0x4e, g: 0x4e, b: 0x4e },
    Color { r: 0x58, g: 0x58, b: 0x58 },
    Color { r: 0x60, g: 0x60, b: 0x60 },
    Color { r: 0x66, g: 0x66, b: 0x66 },
    Color { r: 0x76, g: 0x76, b: 0x76 },
    Color { r: 0x80, g: 0x80, b: 0x80 },
    Color { r: 0x8a, g: 0x8a, b: 0x8a },
    Color { r: 0x94, g: 0x94, b: 0x94 },
    Color { r: 0x9e, g: 0x9e, b: 0x9e },
    Color { r: 0xa8, g: 0xa8, b: 0xa8 },
    Color { r: 0xb2, g: 0xb2, b: 0xb2 },
    Color { r: 0xbc, g: 0xbc, b: 0xbc },
    Color { r: 0xc6, g: 0xc6, b: 0xc6 },
    Color { r: 0xd0, g: 0xd0, b: 0xd0 },
    Color { r: 0xda, g: 0xda, b: 0xda },
    Color { r: 0xe4, g: 0xe4, b: 0xe4 },
    Color { r: 0xee, g: 0xee, b: 0xee },
];

main.rs

extern crate clap;
extern crate image;
extern crate term;
extern crate term_size;

mod colors;

use std::fs::File;
use std::io::{
    stdin,
    Error,
    Read,
    Seek,
    SeekFrom,
    BufReader,
};
use clap::{
    App,
    Arg,
};
use image::{
    load,
    load_from_memory,
    guess_format,
    Rgba,
    Pixel,
    RgbaImage,
    ImageError
};
use colors::{Color, COLORS};

fn read_image_from_file(mut file: File) -> Result<RgbaImage, ImageError> {
    let mut magic_buf = [0 as u8; 512];
    file.read(&mut magic_buf)?;
    file.seek(SeekFrom::Start(0))?;
    let reader = BufReader::new(file);
    let format = guess_format(&magic_buf)?;
    load(reader, format).map(|image| image.to_rgba())
}
fn read_image_from_stdin() -> Result<RgbaImage, ImageError> {
    let mut buf = vec![];
    stdin().read_to_end(&mut buf).unwrap();
    load_from_memory(buf.as_slice()).map(|image| image.to_rgba())
}

fn abs_sub(a: u8, b: u8) -> u32 {
    (if a > b {
        a - b
    } else {
        b - a
    }) as u32
}

fn get_distance(a: &Color, b: &Color) -> u32 {
    abs_sub(a.r, b.r).pow(2) + abs_sub(a.g, b.g).pow(2) + abs_sub(a.b, b.b).pow(2)
}

fn get_closest_color(pixel: &Rgba<u8>) -> u16 {
    let (r, g, b, _) = pixel.channels4();
    let mut best_distance = std::u32::MAX;
    let mut best_color: u16 = 0;
    for i in 0..256 {
        let color = &COLORS[i as usize];
        let distance = get_distance(color, &Color { r: r, g: g, b: b });
        if distance < best_distance {
            best_distance = distance;
            best_color = i;
        }
    }
    return best_color;
}

fn print_image(image: RgbaImage, width: u32) -> Result<(), Error> {
    let mut t = term::stdout().unwrap();
    let (size_x, size_y) = image.dimensions();
    let step = (size_x / width) as u32;
    for y in 0..(size_y / 2 / step) {
        for x in 0..(size_x / step) {
            let fgcolor = get_closest_color(image.get_pixel(x * step, y * 2 * step));
            let bgcolor = get_closest_color(image.get_pixel(x * step, (y * 2 + 1) * step));
            t.fg(fgcolor)?;
            t.bg(bgcolor)?;
            write!(t, "▀")?;
        }
        t.reset()?;
        write!(t, "\n")?;
    }
    Ok(())
}

fn get_default_width() -> u32 {
    term_size::dimensions().map(|sizes| sizes.0 as u32)
        .map_or(80, |width| if width > 80 { 80 } else { width })
}

fn main() {
    let matches = App::new("imgview")
        .version("0.1.0")
        .about("Render images to the terminal in 256 colours")
        .arg(Arg::with_name("width")
             .short("w")
             .long("width")
             .value_name("COLUMNS")
             .takes_value(true))
        .arg(Arg::with_name("input")
             .index(1))
        .get_matches();

    let width = u32::from_str_radix(matches.value_of("width").unwrap_or(""), 10)
        .unwrap_or_else(|_| get_default_width());
    let file_path = matches.value_of("input").unwrap_or("-");

    let image = (
        if file_path != "-" {
            match File::open(file_path) {
                Ok(file) => read_image_from_file(file),
                Err(err) => Err(ImageError::IoError(err)),
            }
        } else {
            read_image_from_stdin()
        }
    ).unwrap();
    print_image(image, width).unwrap();
}