Low frequency watermark

Usage this package

• image crate will be utilized to open and save image
  • If you don't need to save and load from a file, you don't need to add image crate.

cargo add lf-watermark image

Example code

• Simple example code to embed Hello, World! to an image by DCT.

    let img = image::open("image.png").unwrap();
    let watermark = "Hello, World!";
    let watermarked_img = lf_watermark::embed_watermark_color(&img, watermark);
    assert!(watermarked_img.is_ok(), "Failed to embed watermark");
    assert!(
        watermarked_img.unwrap().save("output.png").is_ok(),
        "Failed to save image"
    )