PHP Doku:: Analyzes the colors within a reference image - gmagick.quantizeimage.html

Verlauf / Chronik / History: (1) anzeigen

Sie sind hier:
Doku-StartseitePHP-HandbuchFunktionsreferenzBildverarbeitung und -generierungGmagickThe Gmagick classGmagick::quantizeimage

Ein Service von Reinhard Neidl - Webprogrammierung.

The Gmagick class

<<Gmagick::profileimage

Gmagick::quantizeimages>>

Gmagick::quantizeimage

(PECL gmagick >= Unknown)

Gmagick::quantizeimageAnalyzes the colors within a reference image

Beschreibung

public void Gmagick::quantizeimage ( int $numColors , int $colorspace , int $treeDepth , bool $dither , bool $measureError )

Analyzes the colors within a reference image and chooses a fixed number of colors to represent the image. The goal of the algorithm is to minimize the color difference between the input and output image while minimizing the processing time.

Parameter-Liste

numColors

The number of colors.

colorspace

Perform color reduction in this colorspace, typically RGBColorspace.

treeDepth

Normally, this integer value is zero or one. A zero or one tells Quantize to choose a optimal tree depth of Log4(number_colors).% A tree of this depth generally allows the best representation of the reference image with the least amount of memory and the fastest computational speed. In some cases, such as an image with low color dispersion (a few number of colors), a value other than Log4(number_colors) is required. To expand the color tree completely, use a value of 8.

dither

A value other than zero distributes the difference between an original image and the corresponding color reduced algorithm to neighboring pixels along a Hilbert curve.

measureError

A value other than zero measures the difference between the original and quantized images. This difference is the total quantization error. The error is computed by summing over all pixels in an image the distance squared in RGB space between each reference pixel value and its quantized value.

Rückgabewerte

The Gmagick object on success

Fehler/Exceptions

Wirft bei einem Fehler eine GmagickException.


Keine BenutzerBeiträge.
- Beiträge aktualisieren...



PHP Powered Diese Seite bei php.net
The PHP manual text and comments are covered by the Creative Commons Attribution 3.0 License © the PHP Documentation Group - Impressum - mail("TO:Reinhard Neidl",...)