proc absolute(img: Image): Image {....raises: [VipsError], tags: [], forbids: [].}

proc blur(img: Image; sigma: float64 = 1.0): Image {....raises: [VipsError],
    tags: [], forbids: [].}

proc canny(img: Image): Image {....raises: [VipsError], tags: [], forbids: [].}

proc clamp(img: Image): Image {....raises: [VipsError], tags: [], forbids: [].}

proc gamma(img: Image; exponent: float64 = 2.2): Image {....raises: [VipsError],
    tags: [], forbids: [].}

proc invert(img: Image): Image {....raises: [VipsError], tags: [], forbids: [].}

proc prewitt(img: Image): Image {....raises: [VipsError], tags: [], forbids: [].}

proc scharr(img: Image): Image {....raises: [VipsError], tags: [], forbids: [].}

proc sharpen(img: Image): Image {....raises: [VipsError], tags: [], forbids: [].}

proc sobel(img: Image): Image {....raises: [VipsError], tags: [], forbids: [].}