Rust program that runs ffmpeg and generates a cursed video from the specified binary file

main.rs

use std::fs::metadata;
use std::process::Command;
use std::f64;

fn main() {
    let program_path = std::env::args().nth(1).unwrap_or_else(|| {
        "/Applications/Ghostty.app/Contents/MacOS/ghostty".to_string()
    });

    let file_size = metadata(&program_path)
        .expect("Failed to stat file")
        .len();

    const PIX_FMT: &str = "rgb555";
    const BYTES_PER_PIXEL: u64 = 2;
    const ASPECT_TARGET: f64 = 16.0 / 10.0;
    const MAX_DIM: u32 = 512;

    let mut best_w = 0;
    let mut best_h = 0;
    let mut best_err = f64::MAX;

    for w in (8..=MAX_DIM).rev() {
        for h in (8..=MAX_DIM).rev() {
            let frame_size = w as u64 * h as u64 * BYTES_PER_PIXEL;
            if frame_size == 0 || file_size % frame_size != 0 {
                continue;
            }

            let aspect = w as f64 / h as f64;
            let err = (aspect - ASPECT_TARGET).powi(2);

            if err < best_err {
                best_w = w;
                best_h = h;
                best_err = err;
            }
        }
    }

    if best_w == 0 {
        eprintln!("No suitable resolution found for file size {file_size}");
        std::process::exit(1);
    }

    println!(
        "Best resolution: {}x{} (aspect ~ {:.3}, frames = {})",
        best_w,
        best_h,
        best_w as f64 / best_h as f64,
        file_size / (best_w as u64 * best_h as u64 * BYTES_PER_PIXEL)
    );

    let ffmpeg_status = Command::new("ffmpeg")
        .args([
            "-f", "u8",
            "-ar", "44100",
            "-ac", "2",
            "-i", &program_path,
            "-f", "rawvideo",
            "-pixel_format", PIX_FMT,
            "-video_size", &format!("{}x{}", best_w, best_h),
            "-framerate", "25",
            "-i", &program_path,
            "-vf", "scale=1280:720:flags=neighbor",
            "-c:v", "libsvtav1",
            "-b:v", "50000k",
            "-c:a", "libopus",
            "-shortest",
            "-y", "output.webm",
        ])
        .status()
        .expect("Failed to run ffmpeg");

    if !ffmpeg_status.success() {
        eprintln!("ffmpeg exited with error");
        std::process::exit(1);
    }
}