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PHP image processing function examples and PHP verification code

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2016-07-25 08:51:45829browse

  3. //Prepare canvas

  4. $im = imagecreatetruecolor(500, 300);

  5. //Prepare paint

  6. $black = imagecolorallocate( $im, 0, 0, 0);

  7. $white = imagecolorallocate($im, 255, 255, 255);

  8. //The background is filled with Black

  9. imagefill($im,0,0, $black);

  10. //Draw a rectangle and fill it with white

  11. imagefilledellipse($im, 258, 151, 200, 200, $white );
  12. //Output to the browser or save it
  13. header("content-type:image/png");
  14. //Output the image
  15. imagepng($im);

  16. // Close the canvas

  17. imagedestroy($im);
  18. ?>

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php image processing function 1. Mathematical functions 2. Image processing function

Math functions: 1,max(); 2,min(); 3. mt_rand(); randomly pick a number

  2. echomt_rand(1,5);
  3. ?>
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mt_rand randomly picks a value

  4. //Randomly pick a value from an array
  5. $arr = array("a","b","c","d","e ");

  6. $rkey = mt_rand(0,count($arr)-1);

  7. echo $arr[$rkey];

  8. ?> ;

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4.ceil(); ceiling 5.floor(); 6.round(); rounding

  4. echo ceil(2.4);//3
  5. echo floor(2.4);//2
  6. echo round(2.4);//2
  7. echo round(2.6 );//3

  8. ?>

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6.pi(); //π takes pi

  2. echo(pi());
  3. echo M_PI;
  4. ?>
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image processing function usage scenarios 1.Verification code 2.Zoom 3.Crop 4. Watermark

Five steps to create an image in PHP 1. Prepare the canvas 2. Prepare paint 3. Draw images or text on the canvas 4. Output the final image or Caocun final image 5. Release canvas resources

Example:

  4. //1. Prepare canvas
  5. $im = imagecreatetruecolor(500,300);
  6. //2. Prepare paint
  7. $black = imagecolorallocate($im, 0, 0 , 0);
  8. $white = imagecolorallocate($im, 255, 255, 255);

  9. //3. Draw images or text on the canvas

  10. //If the background is not filled, the default It's black
  11. imageellipse($im,258,151,200,200,$white);

  12. //4. Output the final image or save the final image

  13. header("content-type:image/png");
  14. imagepng($im);
  15. //5. Release canvas resources
  16. imagedestroy($im);
  17. ?>

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Draw the image: imagefill(); imagesetpixel();//draw pixels imageline();//Draw line imagerectangle();//Draw a rectangle imagepolygon();//Draw a polygon imageellipse();//Draw an ellipse imageare(); draw an arc imagechar();//Draw a character horizontally imagestring();//Draw a line of string horizontally

Example:

  3. //Draw lines

  5. //1. Prepare canvas
  6. $im = imagecreatetruecolor(500,300);
  7. //2. Prepare paint
  8. $black = imagecolorallocate($ im, 0, 0, 0);
  9. $white = imagecolorallocate($im, 255, 255, 255);

  10. //3. Draw images or text on the canvas

  11. //If The background is not filled, the default is black
  12. imageline($im,0,0,500,300,$white);
  13. imageline($im,0,300,500,0,$white);
  14. imageline($im,0,150,500,150,$white);
  15. imageline( $im,250,0,250,300,$white);

  16. //4. Output the final image or save the final image

  17. header("content-type:image/png");
  18. imagepng($ im);
  19. //5. Release canvas resources
  20. imagedestroy($im);
  21. ?>

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Example:

  3. //Add interferon

  5. //1. Prepare canvas
  6. $im = imagecreatetruecolor(500,300);
  7. //2. Prepare paint
  8. $black = imagecolorallocate( $im, 0, 0, 0);
  9. $white = imagecolorallocate($im, 255, 255, 255);

  10. //3. Draw images or text on the canvas

  11. // Generate random points
  12. for ($i=0; $i < 1000; $i++) {

  13. imagesetpixel($im,mt_rand(0,500),mt_rand(0,300),$white) ;

  14. }

  15. //Generate random lines

  16. for ($j=0; $j < 100; $j++) {

  17. imageline($ im, mt_rand(0,500), mt_rand(0,300), mt_rand(0,500), mt_rand(0,300), $white);
  18. }//4. Output the final image or save the final image
  19. header("content-type:image/png ");
  20. imagepng($im);
  21. //5. Release canvas resources
  22. imagedestroy($im);
  23. ?>

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Example:

  3. //Draw a rectangle:

  5. //1. Prepare the canvas
  6. $im = imagecreatetruecolor(500,300);
  7. //2. Prepare the paint
  8. $black = imagecolorallocate( $im, 0, 0, 0);
  9. $white = imagecolorallocate($im, 255, 255, 255);

  10. //3. Draw an image or text on the canvas

  11. imagerectangle( $im, 20, 20, 480, 280, $white);//
  12. imagefilledrectangle($im, 20, 20, 480, 280, $white);//Filling

  13. // 4. Output the final image or save the final image

  14. header("content-type:image/png");
  15. imagepng($im);
  16. //5. Release canvas resources
  17. imagedestroy($im);
  18. ?> < ;/p>
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Example:

  3. //imagepolygon draw polygon_draw triangle

  5. //1. Prepare canvas
  6. $im = imagecreatetruecolor(500,300);
  7. //2. Prepare paint
  8. $black = imagecolorallocate($im, 0, 0, 0);
  9. $white = imagecolorallocate($im, 255, 255, 255);

  10. //3. Draw images or text on the canvas

  11. $arr = array(
  12. 250,20,
  13. 60,240,
  14. 440,240
  15. );
  16. imagepolygon($im, $arr, 3, $white);

  17. //4. Output final image or save the final image

  18. header("content-type:image/png");
  19. imagepng($im);
  20. //5. Release canvas resources
  21. imagedestroy($im);
  22. ?>

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Example to draw a 3D pie chart

  4. //1. Prepare canvas
  5. $im = imagecreatetruecolor(500,300);
  6. //2. Prepare paint
  7. $black = imagecolorallocate($im, 0, 0 , 0);
  8. $red = imagecolorallocate($im, 255, 0, 0);
  9. $grayred = imagecolorallocate($im, 255, 100, 100);
  10. $green = imagecolorallocate($im, 0, 255, 0 );
  11. $blue = imagecolorallocate($im, 0, 0, 255);
  12. $gray = imagecolorallocate($im, 200, 200, 200);
  13. $white = imagecolorallocate($im, 255, 255, 255);

  14. //3. Draw images or text on the canvas

  15. for ($i=0; $i < 10; $i++) {
  16. imagefilledarc($im, 250, 150+$ i, 200, 200, 0, 70, $gray,IMG_ARC_PIE);
  17. imagefilledarc($im, 250, 150+$i, 200, 200, 70, 190, $grayred,IMG_ARC_PIE);
  18. imagefilledarc($im, 250

  19. }

  20. imagefilledarc($im, 250, 150, 200, 200, 0, 70, $white,IMG_ARC_PIE);
  21. imagefilledarc($im, 250, 150, 200, 200, 70, 190, $red,IMG_ARC_PIE);
  22. imagefilledarc($im, 250, 150, 200, 200, 190, 270, $green,IMG_ARC_PIE);
  23. imagefilledarc($im, 250, 150, 200, 200, 270, 360, $blue ,IMG_ARC_PIE);

  24. //4. Output the final image or save the final image

  25. header("content-type:image/png");
  26. imagepng($im);
  27. //5 .Release canvas resources
  28. imagedestroy($im);
  29. ?>

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Example:

  3. //Write text:

  5. //1. Prepare canvas
  6. $im = imagecreatetruecolor(500,300);
  7. //2. Prepare paint
  8. $black = imagecolorallocate( $im, 0, 0, 0);
  9. $red = imagecolorallocate($im, 255, 0, 0);
  10. $grayred = imagecolorallocate($im, 255, 100, 100);
  11. $green = imagecolorallocate($im , 0, 255, 0);
  12. $blue = imagecolorallocate($im, 0, 0, 255);
  13. $gray = imagecolorallocate($im, 200, 200, 200);
  14. $white = imagecolorallocate($im, 255 , 255, 255);

  15. //3. Draw images or text on the canvas

  16. $str= "PHP is very much";

  17. imagestring($im, 5, 260, 160, $str, $green);

  18. //4. Output the final image or save the final image
  19. header("content-type:image/png") ;
  20. imagepng($im);
  21. //5. Release canvas resources
  22. imagedestroy($im);
  23. ?>

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Example:

  3. //Write a single character:

  5. //1. Prepare canvas
  6. $im = imagecreatetruecolor(500,300);
  7. //2. Prepare paint
  8. $black = imagecolorallocate ($im, 0, 0, 0);
  9. $red = imagecolorallocate($im, 255, 0, 0);
  10. $grayred = imagecolorallocate($im, 255, 100, 100);
  11. $green = imagecolorallocate($ im, 0, 255, 0);
  12. $blue = imagecolorallocate($im, 0, 0, 255);
  13. $gray = imagecolorallocate($im, 200, 200, 200);
  14. $white = imagecolorallocate($im, 255, 255, 255);

  15. //3. Draw images or text on the canvas

  16. $str= "P";

  17. imagechar($im, 5, 260, 160, $str, $green);

  18. //4. Output the final image or save the final image
  19. header("content-type:image/png");
  20. imagepng($im);
  21. //5. Release canvas resources
  22. imagedestroy($im);
  23. ?>

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Example,

  3. //Write on the picture

  5. //1. Prepare the canvas
  6. $im = imagecreatetruecolor(500,300);
  7. //2. Prepare the paint
  8. $black = imagecolorallocate ($im, 0, 0, 0);
  9. $red = imagecolorallocate($im, 255, 0, 0);
  10. $grayred = imagecolorallocate($im, 255, 100, 100);
  11. $green = imagecolorallocate($ im, 0, 255, 0);
  12. $blue = imagecolorallocate($im, 0, 0, 255);
  13. $gray = imagecolorallocate($im, 200, 200, 200);
  14. $white = imagecolorallocate($im, 255, 255, 255);

  15. //3. Draw images or text on the canvas

  16. $str= "junzaivip";

  17. $file = " E:/PHP/fonts/SIMYOU.TTF";
  18. // $file = "fonts/SIMYOU.TTF";

  19. imagettftext($im, 50, 0, 100, 200, $ green, $file, $str);

  20. //4. Output the final image or save the final image

  21. header("content-type:image/png");
  22. imagepng($im) ;
  23. //5. Release canvas resources
  24. imagedestroy($im);
  25. ?>

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PHP verification code design

  4. //Prepare canvas
  5. $im = imagecreatetruecolor(100,50);
  6. //Prepare paint
  7. $black = imagecolorallocate($im, 0, 0, 0 );
  8. $gray = imagecolorallocate($im, 200, 200, 200);

  9. //Fill the background

  10. imagefill($im, 0, 0, $gray);

  11. //Text coordinates

  12. $x = (100-4*20)/2 + 6;
  13. $y = (50-20)/2 + 20;

  14. //Draw images or text on the canvas

  15. //Connect three arrays

  16. $strarr = array_merge(range(1, 9),range(a, z),range(A , Z));

  17. //Shuffle the array

  18. shuffle($strarr);

  19. //array_slice: Take the first few digits of the array

  20. // Join turns the array into a string, and uses the first variable as the delimiter
  21. $str = join('',array_slice($strarr, 0,4));

  22. $file = "E:/PHP/fonts/msyh.ttf";

  23. // $file = "fonts/msyh.ttf";

  24. imagettftext($im, 20, 0, $x, $ y, $black, $file, $str);

  25. //Output the final image or save the final image

  26. header("content-type:image/png");
  27. imagepng($im );
  28. //Release canvas resources
  29. imagedestroy($im);
  30. ?>

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php verification code design: This involves two pages: index.php & reg.php Description:

This verification code version only implements dynamic acquisition of verification images Compare the verification code on the front-end registration page with the verification code on the generated image The verification code is randomly composed of numbers, lowercase letters, and uppercase letters

index.php//Realize user registration

  5. reg

  9. User registration page

  19. < td>

    23. Name:
    Password:
    Verification code:
    < ;/p>

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reg.php//Used to verify whether the verification code is correct

  4. session_start();
  5. // echo $_POST['username'];
  6. // echo $_POST['password'];
  7. $code = strtolower( $_POST['vcode']);

  8. // echo $code;

  9. // echo "

    "; </li>
<li>// print_r( $_SESSION); </li>
<li>// echo "
    ";
  10. $vstr = strtolower($_SESSION['vstr']);

  11. if ($code==$vstr) {

  12. //Realize page jump
  13. echo "<script>location='http://www.xingzuo51.com'</script>";
  14. }else{
  15. echo "<script>alert(' Verification code input error')</script>";
  16. //echo "Return to registration page";
  17. echo "<script>location=' index.php'</script>";

  18. }

  20. ?>

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auth.php is used to generate verification codes

  4. //Open session, there cannot be any output before opening session
  5. session_start();

  7. $width = 50; //Verification code background width
  8. $height = 26; //Verification code background high speed
  9. $fonttype = 10; //Verification code font size
  10. //Prepare canvas
  11. $im = imagecreatetruecolor($width,$height);
  12. //Prepare paint
  13. $black = imagecolorallocate($im, 0, 0, 0);
  14. $gray = imagecolorallocate($im, 200, 200, 200);

  15. //Fill the background

  16. imagefill($im, 0, 0, $gray);

  17. //Text coordinates

  18. $x = ($width-4*$fonttype)/2 +2;
  19. $y = ($height-$fonttype)/2 + $fonttype;

  20. //Draw images or text on the canvas

  21. //Connect three arrays

  22. $strarr = array_merge(range(1, 9),range(a, z),range(A, Z));

  23. //Shuffle the array

  24. shuffle($strarr);

    ($strarr, 0,4));

  25. //Put $str into session to facilitate use on all pages

  26. $_SESSION['vstr'] = $str;

  27. $file = "E:/PHP/fonts/msyh.ttf";

  28. // $file = "fonts/msyh.ttf";

  29. imagettftext($ im, $fonttype, 0, $x, $y, $black, $file, $str);

  30. //Output the final image or save the final image

  31. header("content-type: image/png");
  32. imagepng($im);
  33. //Release canvas resources
  34. imagedestroy($im);
  35. ?>

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php verification code design: Page jump: 1.php jump

    $im = imagecreatefromjpeg("lyf.jpg");

  1. $x = imagesx($im);

  2. $y = imagesy($im);

  3. echo $x . $y;

  4. exit;

  5. header("content-type:image/jpeg");

  6. imagejpeg($im);
  7. ?>

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Method 2 to get the size of the image:

    $imgfile = "lyf.jpg";

  1. $imgarr = getimagesize($imgfile);

  2. echo "

    "; </li>
<li>print_r($imgarr); </li>
<li>echo "
    ";

  3. exit;

  5. echo $x . $y;

  6. header("content-type:image/jpeg ");

  7. imagejpeg($im);
  8. ?>

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Image zoom function:

  4. $imgfile = "lyf.jpg";

  5. //In order to get the width and height of the large image

  6. $imgarr = getimagesize( $imgfile);

  7. $maxw = $imgarr[0];

  8. $maxh = $imgarr[1];
  9. $maxt = $imgarr[2];
  10. $maxm = $imgarr[ 'mime'];

  11. //In order to turn large images into resources

  12. $im = imagecreatefromjpeg("lyf.jpg");

  13. //Small image resources

  14. $minw = 100;
  15. $minh = 400;

  17. //Equal scaling
  18. if (($minw/$maxw)> ;($minh/$maxh)) {
  19. $rate = $minh/$maxh ;
  20. }else{
  21. $rate = $minw / $maxw ;
  22. }

  23. $minw = floor ($maxw * $rate);

  24. $minh = floor($maxh * $rate);
  25. $minim = imagecreatetruecolor($minw, $minh);

  26. //Zoom the large image Into a small image

  27. imagecopyresampled($minim, $im, 0, 0, 0, 0, $minw, $minh, $maxw, $maxh);

  28. //Small image output

  29. header ("content-type:{$maxm}");

  30. //Determine the type

  31. switch ($maxt) {
  32. case 1:
  33. $imageout = "imagegif";
  34. break;
  35. case 2:
  36. $imageout = "imagejpeg";
  37. break;
  38. case 3:
  39. $imageout = "imagepng";
  40. break;

  41. }

  42. $imageout($minim);

  43. $minfilename = "s_".$imgfile;
  44. $imageout($minim,$minfilename);
  45. // imagejpeg($im);

  47. / /Release resources
  48. imagedestroy($maxim);
  49. imagedestroy($minim);
  50. ?>

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Image cropping function: imagecopyresampled();

Image watermark function: imagecopy();

3, Crop

4, watermark

  4. $maxim = imagecreatefromjpeg("lyf.jpg");
  5. $minim = imagecreatefromjpeg("lyf.jpg");

  7. $maxh = imagesy($maxim);

  8. $minw = imagesx($minim);

  9. $minh = imagesy($minim); < ;/p>

  10. imagecopy($maxim, $minim, $maxw-$minw, $maxh-$minh, 0, 0, $minw, $minh);

  11. header("content-type:image/jpeg");

  12. imagejpeg($mamim);

  13. ?>

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