DZone Snippets: image code

Simple Resize PIL Image with python

manatlan (manatlan) — Thu, 17 Jul 2008 09:48:29 GMT

// description of your code here



def resize(im,percent):

    """ retaille suivant un pourcentage 'percent' """

    w,h = im.size

    return im.resize(((percent*w)/100,(percent*h)/100))



def resize2(im,pixels):

    """ retaille le coté le plus long en 'pixels' 

        (pour tenir dans une frame de pixels x pixels)

    """

    (wx,wy) = im.size

    rx=1.0*wx/pixels

    ry=1.0*wy/pixels

    if rx>ry:

        rr=rx

    else:

        rr=ry



    return im.resize((int(wx/rr), int(wy/rr)))

Generate a graph using Gruff

jrobertson (James Robertson) — Sun, 24 Feb 2008 18:52:14 GMT

This Ruby code produced a graph using gruff. The output shows a line graph [twitxr.com] for the different fruits. Source code origin: Gruff Update With Bar Graphs | Ruby on Rails for Newbies [rubyonrails.com]



require 'gruff'



g = Gruff::Line.new

g.title = "My Graph" 



g.data("Apples", [1, 2, 3, 4, 4, 3])

g.data("Oranges", [4, 8, 7, 9, 8, 9])

g.data("Watermelon", [2, 3, 1, 5, 6, 8])

g.data("Peaches", [9, 9, 10, 8, 7, 9])



g.labels = {0 => '2003', 2 => '2004', 4 => '2005'}



g.write('my_fruity_graph.png')

Note: I executed the code within an irb session on my Gentoo box. With Gentoo, Gruff was installed [gentoo-portage.com] using the command emerge -va gruff. I tried installing it on Ubuntu but ran into some difficulty, even with help from the article install rmagick ubuntu [dzone.com].

*udpate 21:48 24-Feb*

The following code does exactly as the same code above, however it uses XML to separate the data from the process, making it easier and more efficient to build graphs.



#!/usr/bin/ruby

# file: xml2gruff.rb



require 'rexml/document'

require 'gruff'

include REXML



class Xml2Gruff

  

  def initialize(filename)

    file = File.new(filename, 'r')

    doc = Document.new(file)

    # get the title

    @title = doc.root.elements['summary/title'].text

    

    @record = Hash.new

    # get each record

    doc.root.elements.each('records/item') {|item|

      avalues = Array.new

      item.elements.each('values/value') { |value| avalues << value.text.to_i }

      @record[item.elements['label'].text] = avalues

    }

    

    # get the summary labels

    @labels = Hash.new  

    doc.root.elements.each('summary/scale/label') {|l| @labels[l.elements['value'].text.to_i] = l.elements['title'].text} 

    

  end

  

  def save_line_graph(filename)



    g = Gruff::Line.new

    g.title = @title 

    @record.each {|label, data| g.data(label, data) }

    g.labels = @labels

    g.write(filename)



  end

end



if __FILE__ == $0

 x2g = Xml2Gruff.new('my_fruit.xml')

 x2g.save_line_graph('my_fruit2.png')

end

file: my_fruit.xml

Reference: gruff's gruff-0.2.9 Documentation [rubyforge.org]
gruff graphs for ruby by geoffrey grosenbach [topfunky.com]

C#: Resize An Image While Maintaining Aspect Ratio and Maximum Height

cornerblue (CornerBLUE, Inc.) — Thu, 19 Jul 2007 22:55:39 GMT

// This allows us to resize the image. It prevents skewed images and
// also vertically long images caused by trying to maintain the aspect
// ratio on images who's height is larger than their width



public void ResizeImage(string OriginalFile, string NewFile, int NewWidth, int MaxHeight, bool OnlyResizeIfWider)

{

	System.Drawing.Image FullsizeImage = System.Drawing.Image.FromFile(OriginalFile);



	// Prevent using images internal thumbnail

	FullsizeImage.RotateFlip(System.Drawing.RotateFlipType.Rotate180FlipNone);

	FullsizeImage.RotateFlip(System.Drawing.RotateFlipType.Rotate180FlipNone);



	if (OnlyResizeIfWider)

	{

		if (FullsizeImage.Width <= NewWidth)

		{

			NewWidth = FullsizeImage.Width;

		}

	}



	int NewHeight = FullsizeImage.Height * NewWidth / FullsizeImage.Width;

	if (NewHeight > MaxHeight)

	{

		// Resize with height instead

		NewWidth = FullsizeImage.Width * MaxHeight / FullsizeImage.Height;

		NewHeight = MaxHeight;

	}



	System.Drawing.Image NewImage = FullsizeImage.GetThumbnailImage(NewWidth, NewHeight, null, IntPtr.Zero);



	// Clear handle to original file so that we can overwrite it if necessary

	FullsizeImage.Dispose();



	// Save resized picture

	NewImage.Save(NewFile);

}

Set image opacity

mstampar (Miroslav Stampar) — Tue, 24 Apr 2007 22:46:02 GMT



        public static Image SetOpacity(Image original, float opacity)

        {

            Bitmap temp = new Bitmap(original.Width, original.Height);

            Graphics g = Graphics.FromImage(temp);

            ColorMatrix cm = new ColorMatrix();

            cm.Matrix33 = opacity;



            ImageAttributes ia = new ImageAttributes();

            ia.SetColorMatrix(cm, ColorMatrixFlag.Default, ColorAdjustType.Bitmap);

            g.DrawImage(original, new Rectangle(0, 0, temp.Width, temp.Height), 0, 0, original.Width, original.Height, GraphicsUnit.Pixel, ia);

            g.Dispose();



            return temp;

        }

Avatar Resizer

kedare (Mathieu Poussin) — Mon, 23 Apr 2007 17:13:46 GMT

I go on a lot of Bulletin Board, every has its own limits of size for the avatars, instead of the resize manually I created a script which does it for me with RMagick



#!/usr/bin/ruby

require "RMagick"

$SIZES = [80 , 100 , 110 , 128]



if !ARGV[0]

  puts "Usage: mk_avatars.rb SourceAvatarPath"

  exit

end



image = Magick::Image.read(ARGV[0]).first

$SIZES.each do |sz|

  puts "Generating Avatar : #{sz}"

  out = image.thumbnail(sz,sz)

  file = "out_#{sz}.#{image.format}"

  out.write(file)

end

thumbnail with gd

oso96_2000 (oso96_2000) — Fri, 20 Apr 2007 00:30:16 GMT

Function that makes a thumbnail of a imagen and keeps it's proportion. $the fourth parameter ($fill) makes that, if the image is smaller than the size we want, the function expands it. It shows the image directly to the browser, but can be easily modificed to save the imagen on a directory.

Funcion que hace una miniatura de una imagen manteniendo su proporcion individual. El cuarto parametro ($fill) hace que, si la imagen es mas pequeña del tamaño deseado, la expande. Muestra la imagen directamente en el navegador, pero puede ser facilmente modificada para guardarla en un directorio.



function thumb($img, $w, $h, $fill = true) {

	if (!extension_loaded('gd') && !extension_loaded('gd2')) {

		trigger_error("No dispones de la libreria GD para generar la imagen.", E_USER_WARNING);

		return false;

	}



	$imgInfo = getimagesize($img);

	switch ($imgInfo[2]) {

		case 1: $im = imagecreatefromgif($img); break;

		case 2: $im = imagecreatefromjpeg($img);  break;

		case 3: $im = imagecreatefrompng($img); break;

		default:  trigger_error('Tipo de imagen no reconocido.', E_USER_WARNING);  break;

	}



	if ($imgInfo[0] <= $w && $imgInfo[1] <= $h && !$fill) {

		$nHeight = $imgInfo[1];

		$nWidth = $imgInfo[0];

	}else{

		if ($w/$imgInfo[0] < $h/$imgInfo[1]) {

			$nWidth = $w;

			$nHeight = $imgInfo[1]*($w/$imgInfo[0]);

		}else{

			$nWidth = $imgInfo[0]*($h/$imgInfo[1]);

			$nHeight = $h;

		}

	}

  

	$nWidth = round($nWidth);

	$nHeight = round($nHeight);



	$newImg = imagecreatetruecolor($nWidth, $nHeight);



	imagecopyresampled($newImg, $im, 0, 0, 0, 0, $nWidth, $nHeight, $imgInfo[0], $imgInfo[1]);



	header("Content-type: ". $imgInfo['mime']);



	switch ($imgInfo[2]) {

		case 1: imagegif($newImg); break;

		case 2: imagejpeg($newImg);  break;

		case 3: imagepng($newImg); break;

		default:  trigger_error('Imposible mostrar la imagen.', E_USER_WARNING);  break;

	}

  

	imagedestroy($newImg);

}

?>

Usage/Uso:
thumb("image.png", 200, 200);

php image from database using PEAR::DB

mikewilsonuk (Mike Wilson) — Mon, 26 Mar 2007 08:16:22 GMT

This fetches an image from a MySQL database (I know, a database may not be the best place to keep images). The image is sent to the web client as an image/jpeg.



require_once 'DB.php';



define('DB_SERVER', 'localhost');

define('DB_USER', 'php');

define('DB_PASS', '');

define('DB_DATABASE', 'images');

define('DSN', 'mysql://'.DB_USER.':'.DB_PASS.'@'.DB_SERVER.'/'.DB_DATABASE);



global $db;

$db = DB::connect(DSN);



if (PEAR::isError($db)) {

    die($db->getMessage());

}



if (isset($_GET['id'])) {

  header('Content-Type: image/jpeg');

  $id = $_GET['id'];

  $sql = "select image_data from images where id = ?";

  $result =& $db->query($sql, $id);



  if (PEAR::isError($result)) {

    die($result->getMessage());

  } else {

    if ($result->fetchInto($row)) {

      echo $row[0];

    }

  }



} else {

  echo file_get_contents('broken.png');

}

?>

Extensions to CImg

yondalf (Jonathan Tan) — Thu, 18 Jan 2007 10:04:48 GMT

Extensions to CImg, also for interoperability with Fl_Image





#include "CImg.h"

#include 



using namespace cimg_library;



/* Generates a w*h*3 CImg image from the given rgba data and background colour. */

CImg cimg_from_rgba(unsigned char const* rgba,const unsigned int dimw,const unsigned int dimh, 

		const unsigned char back_r, const unsigned char back_g, const unsigned char back_b) {

	CImg res(dimw,dimh,1,3);

	unsigned char *pR = res.ptr(0,0,0,0), *pG = res.ptr(0,0,0,1), *pB=res.ptr(0,0,0,2);

	const unsigned char *ptrs = rgba;

	for (unsigned int off=res.width*res.height; off>0; --off) {

		*(pR++) = (unsigned char)((ptrs[0] * ptrs[3] + back_r * (255 - ptrs[3])) >> 8);

		*(pG++) = (unsigned char)((ptrs[1] * ptrs[3] + back_g * (255 - ptrs[3])) >> 8);

		*(pB++) = (unsigned char)((ptrs[2] * ptrs[3] + back_b * (255 - ptrs[3])) >> 8);

		ptrs += 4;

	}

	return res;

}



/* Generates a w*h*3 CImg image from the given rgb data. */

CImg cimg_from_rgb(unsigned char const* rgb,const unsigned int dimw,const unsigned int dimh) {

	CImg res(dimw,dimh,1,3);

	unsigned char *pR = res.ptr(0,0,0,0), *pG = res.ptr(0,0,0,1), *pB=res.ptr(0,0,0,2);

	const unsigned char *ptrs = rgb;

	for (unsigned int off=res.width*res.height; off>0; --off) {

		*(pR++) = (unsigned char)*(ptrs++);

		*(pG++) = (unsigned char)*(ptrs++);

		*(pB++) = (unsigned char)*(ptrs++);

	}

	return res;

}



/* Generates a FLTK RGB Image from the given CImg image. */

Fl_RGB_Image* image_from_cimg(CImg const & cimg) {

	const unsigned int wh = cimg.dimx() * cimg.dimy();

	unsigned char *buffer = new unsigned char[3*wh], *nbuffer=buffer;

	const unsigned char 

		*ptr1 = cimg.ptr(0,0,0,0),

		*ptr2 = cimg.dim>1?cimg.ptr(0,0,0,1):ptr1,

		*ptr3 = cimg.dim>2?cimg.ptr(0,0,0,2):ptr1;

	for (unsigned int k=0; k		*(nbuffer++) = (unsigned char)(*(ptr1++));

		*(nbuffer++) = (unsigned char)(*(ptr2++));

		*(nbuffer++) = (unsigned char)(*(ptr3++));

	}

	return new Fl_RGB_Image(buffer, cimg.dimx(), cimg.dimy());

}



/* Returns a resized image to a maximum of the given dimensions, keeping its aspect ratio. */

template CImg get_resize_keep_aspect_ratio(CImg const & cimg, const unsigned int w, const unsigned int h) {

	if (cimg.dimx() * h > cimg.dimy() * w) { // cimg.dimx() / cimg.dimy() > w / h

		return cimg.get_resize(w, cimg.dimy() * w / cimg.dimx(), -100, -100, 5);

	} else {

		return cimg.get_resize(cimg.dimx() * h / cimg.dimy(), h, -100, -100, 5);

	}

}



/* Returns a resized image to a maximum of the given dimensions, keeping its aspect ratio,

 * only if the dimensions given are smaller than the original dimensions. */

template CImg get_resize_if_smaller_keep_aspect_ratio(CImg const & cimg, const unsigned int w, const unsigned int h) {

	if (w < cimg.dimx() || h < cimg.dimy())

		return get_resize_keep_aspect_ratio(cimg, w, h);

	else

		return CImg(cimg);

}

J2ME - Rescale Image

whitetiger () — Tue, 09 Jan 2007 02:08:25 GMT

// description of your code here



private Image rescaleImage(Image image, int width, int height)

	{

		int sourceWidth = image.getWidth();

		int sourceHeight = image.getHeight();

	

		Image newImage = Image.createImage(width, height);

		Graphics g = newImage.getGraphics();

		

		for(int y=0; y		{

			for(int x=0; x			{

				g.setClip(x, y, 1, 1);

				int dx = x * sourceWidth / width;

				int dy = y * sourceHeight / height;

				g.drawImage(image, x-dx, y-dy, Graphics.LEFT | Graphics.TOP);

			}

		}

		

		return Image.createImage(newImage);

	}

www.webscriptexpert.com - Java - Image based tool tips

webscriptexpert (r) — Mon, 11 Dec 2006 03:55:11 GMT

// This script creates 'tool tips' for images. Use as much text as you want. Formatting is controlled through the use of style sheets. The text will resize, according to the screen width and placement of the cursor.

















































Free JavaScripts provided


by Web Script Expert