Interface Image

src/opencv/mod.rs:191–299

Trait for images.

/// Trait for images.
pub trait Image {
    /// Creates a new image with the given width and height.
    fn new(width: usize, height: usize) -> Self;

    /// Returns the internal representation of the image.
    fn buffer(&self) -> *const IplImage;

    /// Returns the RGB value of the pixel at location `(x, y)`.
    ///
    /// If the image is a grayscale image all color components have the same value.
    fn pixel_as_rgb(&self, x: usize, y: usize) -> Option<Rgb>;

    /// Sets the pixel at the location `(x, y)` to the value specified by `p`.
    ///
    /// If the image is a frayscale image the following grayscale value is
    /// set: val = 0.299 * red + 0.587 * green + 0.114 * blue
    fn set_pixel_from_rgb(&self, x: usize, y: usize, p: &Rgb);

    // implemenations ----------------------------------------------------

    /// Returns the width of the image.
    fn width(&self) -> usize { unsafe { (*self.buffer()).width as usize } }

    /// Returns the height of the image.
    fn height(&self) -> usize { unsafe { (*self.buffer()).height as usize } }

    /// Returns the color depth of the image.
    fn depth(&self) -> usize { unsafe { (*self.buffer()).depth as usize } }

    /// Internal method which returns the length of one row in bytes.
    ///
    /// Due to the fact that rows might by aligned the number of bytes might
    /// be greater than the width of the image.
    fn widthstep(&self) -> usize { unsafe { (*self.buffer()).widthstep as usize } }

    /// Returns the number of color components used for this image.
    fn channels(&self) -> usize { unsafe { (*self.buffer()).nchannels as usize } }

    /// Writes the image into a file.
    ///
    /// The file format that is written depends on the extension of the filename.
    /// Supported formats are JPEG, PNG, PPM, PGM, PBM. Returns `false` if file
    /// could not be written and `true` on success.
    fn to_file(&self, fname: &str) -> bool {

        let mut s = fname.to_string();
        s.push('\0');
        unsafe {
            let r = cvSaveImage(
                s.as_ptr()      as *const c_char, 
                self.buffer()   as *const CvArr,
                0               as *const c_int
            );
            r != 0
        }
    }

    /// Copies an area from the given image at location `(x,y )` with width `width`