/**
* Scales the Pix to a specified width and height using a specified scaling type (fill, stretch,
* etc.). Returns a scaled image or a clone of the Pix if no scaling is required.
*
* @param pixs
* @param width
* @param height
* @param type
* @return a scaled image or a clone of the Pix if no scaling is required
*/
public static Pix scaleToSize(Pix pixs, int width, int height, ScaleType type) {
if (pixs == null) throw new IllegalArgumentException("Source pix must be non-null");
int pixWidth = pixs.getWidth();
int pixHeight = pixs.getHeight();
float scaleX = width / (float) pixWidth;
float scaleY = height / (float) pixHeight;
switch (type) {
case FILL:
// Retains default scaleX and scaleY values
break;
case FIT:
scaleX = Math.min(scaleX, scaleY);
scaleY = scaleX;
break;
case FIT_SHRINK:
scaleX = Math.min(1.0f, Math.min(scaleX, scaleY));
scaleY = scaleX;
break;
}
return scale(pixs, scaleX, scaleY);
}
/**
* Scales the Pix to specified x and y scale. If no scaling is required, returns a clone of the
* source Pix.
*
* @param pixs the source Pix
* @param scaleX x-dimension (width) scaling factor
* @param scaleY y-dimension (height) scaling factor
* @return a Pix scaled according to the supplied factors
*/
public static Pix scale(Pix pixs, float scaleX, float scaleY) {
if (pixs == null) throw new IllegalArgumentException("Source pix must be non-null");
if (scaleX <= 0.0f) throw new IllegalArgumentException("X scaling factor must be positive");
if (scaleY <= 0.0f) throw new IllegalArgumentException("Y scaling factor must be positive");
long nativePix = nativeScale(pixs.getNativePix(), scaleX, scaleY);
if (nativePix == 0) throw new RuntimeException("Failed to natively scale pix");
return new Pix(nativePix);
}
/**
* Performs a tophat-like operation.
*
* <p>Notes:
*
* <ol>
* <li>Don't be fooled. This is NOT a tophat. It is a tophat-like operation, where the result is
* similar to what you'd get if you used an erosion instead of an opening, or a dilation
* instead of a closing.
* <li>Instead of opening or closing at full resolution, it does a fast downscale/minmax
* operation, then a quick small smoothing at low res, a replicative expansion of the
* "background" to full res, and finally a removal of the background level from the input
* image. The smoothing step may not be important.
* <li>It does not remove noise as well as a tophat, but it is 5 to 10 times faster. If you need
* the preciseness of the tophat, don't use this.
* <li>The L_TOPHAT_WHITE flag emphasizes small bright regions, whereas the L_TOPHAT_BLACK flag
* emphasizes small dark regions.
* </ol>
*
* @param pixs Source pix (8bpp)
* @param xsize width of max/min op, smoothing; any integer >= 1
* @param ysize height of max/min op, smoothing; any integer >= 1
* @param type L_TOPHAT_WHITE: image - min, or L_TOPHAT_BLACK: max - image
* @return a new Pix image
*/
public static Pix pixFastTophat(Pix pixs, int xsize, int ysize, int type) {
if (pixs == null) throw new IllegalArgumentException("Source pix must be non-null");
if (pixs.getDepth() != 8) throw new IllegalArgumentException("Source pix depth must be 8bpp");
if (xsize < 1 || ysize < 1) throw new IllegalArgumentException("size < 1");
if (type < 0 || type > 1)
throw new IllegalArgumentException("Type must be L_TOPHAT_BLACK or L_TOPHAT_WHITE");
long nativePix = nativePixFastTophat(pixs.mNativePix, xsize, ysize, type);
if (nativePix == 0) throw new RuntimeException("Failed to perform pixFastTophat on image");
return new Pix(nativePix);
}
/**
* Scales the Pix to the specified scale without sharpening.
*
* @param pixs the source Pix (1, 2, 4, 8, 16 and 32 bpp)
* @param scale scaling factor for both X and Y
* @return a Pix scaled while maintaining its aspect ratio
*/
public static Pix scaleWithoutSharpening(Pix pixs, float scale) {
if (pixs == null) throw new IllegalArgumentException("Source pix must be non-null");
if (scale <= 0.0f) throw new IllegalArgumentException("Scaling factor must be positive");
return new Pix(nativeScaleGeneral(pixs.getNativePix(), scale, scale, 0f, 0));
}
