vips 0.2.0

Rust bindings for libvips: fast, low-memory image processing with a safe, ergonomic API.
Documentation 
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use std::time::Instant;
use vips::*;

fn main() -> Result<()> {
    let _instance = VipsInstance::new("perf_smoke", false)?;

    let path = "./examples/images/kodim01.png";
    let img = VipsImage::from_file(path)?;
    let (w, h) = img.size();
    assert!(w > 0 && h > 0 && img.bands() > 0);

    // Path API + large downscale via pre-shrink
    let t0 = Instant::now();
    let thumb = img.resize_reduce(0.05, None, None)?;
    let _ = thumb.write_to_memory_owned()?;
    let d_reduce = t0.elapsed();
    let (tw, th) = thumb.size();
    assert!(tw > 0 && th > 0 && tw < w && th < h);

    let t1 = Instant::now();
    let plain = img.resize(0.05, None, None)?;
    let _ = plain.write_to_memory_owned()?;
    let d_plain = t1.elapsed();

    // Preferred file thumbnail path (shrink-on-load)
    let t2 = Instant::now();
    let file_thumb = VipsImage::thumbnail_file(path, 32, 32, VipsSize::VIPS_SIZE_BOTH)?;
    let _ = file_thumb.write_to_memory_owned()?;
    let d_thumb_file = t2.elapsed();
    let (ftw, fth) = file_thumb.size();
    assert!(ftw > 0 && fth > 0 && ftw <= 32 && fth <= 32);

    // Encoded buffer thumbnail path
    let encoded = img.write_to_buffer(".png")?;
    let t3 = Instant::now();
    let buf_thumb = VipsImage::thumbnail_buffer(&encoded, 32, 32, VipsSize::VIPS_SIZE_BOTH)?;
    let _ = buf_thumb.write_to_memory_owned()?;
    let d_thumb_buf = t3.elapsed();
    assert!(buf_thumb.width() > 0 && buf_thumb.width() <= 32);

    // Owned memory round-trip
    let pixels = vec![128u8; 64 * 64 * 3];
    let mem = VipsImage::from_memory(pixels, 64, 64, 3, VipsBandFormat::VIPS_FORMAT_UCHAR)?;
    let mem_thumb = mem.thumbnail(32, 32, VipsSize::VIPS_SIZE_FORCE)?;
    let bytes = mem_thumb.write_to_memory()?;
    assert!(!bytes.is_empty());

    mem_thumb.write_to_file("/tmp/perf_smoke.png")?;
    mem_thumb.write_jpeg("/tmp/perf_smoke.jpg", Some(80))?;

    println!(
        "size={w}x{h} thumb={tw}x{th} reduce={d_reduce:?} plain={d_plain:?} \
         thumb_file={d_thumb_file:?} thumb_buf={d_thumb_buf:?} mem_bytes={}",
        bytes.len()
    );
    println!("concurrency={} version={}", concurrency(), version_string());
    Ok(())
}