Common GD library functions

01. php

<? PHP

/*

Drawing with Windows graphic Board

1: Create a canvas and set the size.

2: Create a pigment. (red, r Green G blue B, composed of three primary colors. The primary colors can be 0-from weak to strong ).

3: draw lines, write, draw graphics, fill and so on.

4: Save As Image

5. Destroy the canvas.

Using the GD library to draw images is still the above five steps.

*/

// 1: Create a canvas and return it as a resource

$ Im = imagecreatetruecolor (300,200 );

// 2: Create paint

$ Gray = imagecolorallocate ($ im, 100,100,100 );

// 3: Fill the canvas

Imagefill ($ im, 0, 0, $ gray );

// 4: Save As Image

Imagepng ($ im, './01.png ');

// 5: destroy the canvas

Imagedestroy ($ IM );

Echo 'OK ';

-------------------

02. php

<? PHP

// The GD library is disabled by default. You need to enable related options.

// How do I check whether the GD library is enabled?

Print_r (gd_info ());

// You can see an array similar to the following to check whether the GD library is enabled.

Array

(

[Gd version] => bundled (2.0.34 compatible) // GD library version

[FreeType support] => 1

[FreeType linkage] => with FreeType

[T1lib support] =>

[GIF read support] => 1

[GIF create support] => 1

[JPEG support] => 1

[PNG support] => 1

[Wbmp support] => 1

[XPM support] =>

[Xbm support] => 1

[JIS-mapped Japanese font support] =>

)

-------------------

03. php

<? PHP

// Step 1: Create a canvas

// 1: Create a blank canvas and specify the width and height.

// 300*200 blank canvas. The returned value is a resource type.

// Create a canvas. The default background color is pure black.

/*

$ Im = imagecreatetruecolor (300,200 );

Imagepng ($ im, './02.png ');

*/

$ Im = imagecreatefromjpeg ('./he.jpg ');

$ Blue = imagecolorallocate ($ im, 255 );

Imageline ($ im, 0, 0, 800,600, $ blue );

If (imagejpeg ($ im, './03.jpg ')){

Echo 'OK ';

}

?>

-------------------

04. php

<? PHP

$ Im1 = imagecreatetruecolor (1, 300,200 );

$ IM2 = imagecreatetruecolor (600,400 );

$ Blue = imagecolorallocate ($ im1, 255 );

$ Red = imagecolorallocate ($ IM2, 255, 0, 0 );

?>

-------------------

05. php

<? PHP

$ Im = imagecreatetruecolor (600,400 );

$ Red = imagecolorallocate ($ im, 255, 0, 0 );

Imagefill ($ im, 0, 0, $ red );

Header ('content-type: image/JPEG ');

Imagejpeg ($ IM );

Imagedestroy ($ IM );

?>

-------------------

06. php

<? PHP

// Step 5: destroy the canvas

$ Im = imagecreatetruecolor (300,200 );

Imagedestroy ($ IM );

?>

-------------------

07. php

<? PHP

/*

Imageline: Draw line

Imagestring, imagettftext: Write

Imagefill-Region Filling

Imagefilledarc-draw an elliptical arc and fill it

Imagefilledellipse-draw an ellipse and fill it

Imagefilledpolygon-draw a polygon and fill it

Imagefilledrectangle-draw a rectangle and fill it

Imagerectangle: Draw a rectangle

Imagecopy: copy an image

Imagecopymerge: Copy and merge images (transparency can be set .)

Imagecopyresampled: Merge and resize

*/

?>

-------------------

08. php

<? PHP

// Draw Line Learning

/*

Bool imageline (resource $ image, int $ X1, int $ Y1, int $ X2, int $ Y2, int $ color)

*/

// 1: Create a canvas

$ Im = imagecreatefromjpeg ('./home.jpg ');

// 2: Pigment

$ Red = imagecolorallocate ($ im, 255, 0, 0 );

$ Blue = imagecolorallocate ($ im, 255 );

// 3: draw a line

Imageline ($ im, 0, 0, 670,503, $ red );

Imageline ($ im, 0,503,670, 0, $ blue );

// 4: Output

Header ('content-type: image/JPEG ');

Imagejpeg ($ IM );

// 5: Destroy

Imagedestroy ($ IM );

?>

-------------------

09. php

<? PHP

/*

Writing

Bool imagestring (resource $ image, int $ font, int $ X, int $ y, string $ S, int $ col)

Resource $ image: canvas Resource

Int $ Font: size (1-5). The font is default and cannot be changed.

Int $ X, int $ Y: represents the coordinates of the point in the upper left corner of the first character to be written.

String $ S: content to be written

Int $ color: Color

Q: Can I wrap a line?

A: No.

Q: Can I write Chinese?

A: No.

Q: Can I specify a font?

A: No.

*/

$ Im = imagecreatefromjpeg ('./home.jpg ');

$ Blue = imagecolorallocate ($ im, 255 );

Imagestring ($ im, 5,100,100, 'Welcome to shahe ', $ blue );

Header ('content-type: image/JPEG ');

Imagejpeg ($ IM );

-------------------

10. php

<? PHP

Function randname ($ n = 6 ){

If ($ n <= 0 ){

Return '';

}

$ STR = 'abcdefghijkmnpqrstuvwxyzabcdefghijkmnpqrstuvwxyz0123456789 ';

$ STR = substr (str_shuffle ($ Str), 0, $ N );

Return $ STR;

}

// Perform the verification code

$ Im = imagecreatetruecolor (80, 30 );

$ Gray = imagecolorallocate ($ im, 30, 30 );

$ Red = imagecolorallocate ($ im, 255, 0, 0 );

Imagefill ($ im, 0, 0, $ gray );

Imagestring ($ im, 5, 5, randname (4), $ red );

// Output

Header ('content-type: image/JPEG ');

Imagejpeg ($ IM );

-------------------

11. php

<! Doctype HTML public "-// W3C // dtd xhtml 1.0 strict // en" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

<HTML xmlns = "http://www.w3.org/1999/xhtml" lang = "ZH-CN">

<Head>

<Title> create a webpage </title>

<Meta http-equiv = "Content-Type" content = "text/html; charset = UTF-8"/>

<Meta name = "Description" content = ""/>

<Meta name = "keywords" content = ""/>

<SCRIPT type = "text/JavaScript">

Function CHN (){

VaR img0 = Document. getelementsbytagname ('img ') [0];

Img0.src = '10. php? Id = '+ math. Random ();

}

</SCRIPT>

<Style type = "text/CSS">

</Style>

</Head>

<Body>

<Form>

Verification Code: <input type = "text" name = "code"/>

</Form>

</Body>

</Html>

-------------------

12. php

<? PHP

/*

Write Chinese

Imagettftext

You need to provide a TTF Library first.

Array imagettftext (resource $ image, float $ size, float $ angle, int $ X, int $ y, int $ color, string $ fontfile, string $ text)

*/

$ Im = imagecreatefromjpeg ('./home.jpg ');

$ Blue = imagecolorallocate ($ im, 255 );

Imagettftext ($ im, 100,100, $ blue, './msyh. ttf', 'changping Water', away from town noisy ');

Header ('content-type: image/JPEG ');

Imagejpeg ($ IM );

?>

-------------------

13. php

<? PHP

/*

// Draw an ellipse

Create an ellipse on a canvas and 4 data records are required.

Bool imageellipse (resource $ image, int $ CX, int $ cy, int $ W, int $ H, int $ color)

Center: Cx, Cy

Width: W

Height: H

// Draw a rectangle

Bool imagerectangle (resource $ image, int $ X1, int $ Y1, int $ X2, int $ Y2, int $ col)

*/

$ Im = imagecreatetruecolor (400,800 );

$ Gray = imagecolorallocate ($ im, 100,100,100 );

$ Blue = imagecolorallocate ($ im, 255 );

Imagefill ($ im, 0, 0, $ gray );

// Draw an ellipse

Imageellipse ($ im, 200,100, $ blue );

// Draw a rectangle

Imagerectangle ($ im, 100,100,300,200, $ blue );

// Draw a circle

Imageellipse ($ im, 200,300,200,200, $ blue );

// Output

Header ('content-type: image/JPEG ');

Imagejpeg ($ IM );

-------------------

14. php

<? PHP

// Copy an image

/*

Case study: effect of making a bottom Image

[X] is a small image.

[X]

Use a thumbnail to create a large image

{[X] [x]}

*/

/*

Obtain the image width.

Imagesx ()

Obtain the Image Height

Imagesy ()

*/

// Read the image as a canvas Resource

$ Small = imagecreatefrompng ('./feng.png ');

// Determine the size

$ SX = imagesx ($ small); // width of the thumbnail

$ Sy = imagesy ($ small); // width of the thumbnail

// Create a large image canvas

$ Big = imagecreatetruecolor (2 * $ SX + 20, $ Sy );

$ Gray = imagecolorallocate ($ big, 100,100,100); // gray

// Expand the image

Imagefill ($ big, 0, 0, $ gray );

// Copy the thumbnail to the larger image.

/*

Bool imagecopy (resource $ dst_im, resource $ src_im, int $ dst_x, int $ dst_y, int $ src_x, int $ src_y, int $ src_w, int $ src_h)

*/

Imagecopy ($ big, $ small, 0, 0, 0, $ Sx, $ Sy );

Imagecopy ($ big, $ small, $ SX + 20, 0, 0, $ Sx, $ Sy );

// Output

Header ('content-type: image/JPEG ');

Imagejpeg ($ big );

?>

-------------------

15. php

<? PHP

// Fill

$ Im = imagecreatetruecolor (400,400 );

$ Gray = imagecolorallocate ($ im, 100,100,100 );

$ Blue = imagecolorallocate ($ im, 255 );

$ Red = imagecolorallocate ($ im, 255, 0, 0 );

$ Orange = imagecolorallocate ($ im, 248,224,143 );

Imagefill ($ im, 100,100, $ gray );

// Draw an ellipse

Imageellipse ($ im, 200,200,200,200, $ blue );

// Fill in the ellipse

Imagefill ($ im, 200,200, $ red );

// Draw a rectangle and fill it directly.

Imagefilledrectangle ($ im, 0,100,200,200, $ blue );

// Draw an ellipse and fill it directly

Imagefilledellipse ($ im, 200,100, $ orange );

// Output

Header ('content-type: image/JPEG ');

Imagejpeg ($ IM );

?>

-------------------

16. php

<? PHP

// Draw and fill an arc

/*

Bool imagefilledarc (resource $ image, int $ CX, int $ cy, int $ W, int $ H, int $ S, int $ E, int $ color, int $ style)

Style description

Pie: pie

Chord: String

Nofill: do not fill

Edged: edge

0 img_arc_pie

1 img_arc_chord

2 img_arc_nofill

4 img_arc_edged

0000 (pie/arc)

0100 (fill)

-----

0100 = 4 --> slice + fill

0001 (string)

0010 (not filled)

--------

0011 = 3 (straight line)

0001 (string)

0100 (fill) ---> triangle + fill Effect

-----

0101 = 5

0000 (ARC)

0010 (not filled)

-----

0010-> 2-> an arc, but not filled.

*/

$ Im = imagecreatetruecolor (400,400 );

$ Gray = imagecolorallocate ($ im, 100,100,100 );

$ Blue = imagecolorallocate ($ im, 255 );

Imagefill ($ im, 0, 0, $ gray );

Imagefilledarc ($ im, 200,200,200,200, 45,135, $ blue, 2 );

Header ('content-type: image/JPEG ');

Imagejpeg ($ IM );

?>

-------------------

17. php

<? PHP

// Copy an image

/*

Case study: effect of making a bottom Image

[X] is a small image.

[X]

Use a thumbnail to create a large image

{[X] [x]}

*/

/*

Obtain the image width.

Imagesx ()

Obtain the Image Height

Imagesy ()

*/

// Read the image as a canvas Resource

$ Small = imagecreatefrompng ('./feng.png ');

// Determine the size

$ SX = imagesx ($ small); // width of the thumbnail

$ Sy = imagesy ($ small); // width of the thumbnail

// Create a large image canvas

$ Big = imagecreatetruecolor (2 * $ SX + 20, $ Sy );

$ Gray = imagecolorallocate ($ big, 100,100,100); // gray

// Expand the image

Imagefill ($ big, 0, 0, $ gray );

// Copy the thumbnail to the larger image.

/*

Bool imagecopy (resource $ dst_im, resource $ src_im, int $ dst_x, int $ dst_y, int $ src_x, int $ src_y, int $ src_w, int $ src_h)

*/

Imagecopy ($ big, $ small, 0, 0, 0, $ Sx, $ Sy );

Imagecopy ($ big, $ small, $ SX + 20, 0, 0, $ Sx, $ Sy );

// Output

Header ('content-type: image/JPEG ');

Imagejpeg ($ big );

?>

-------------------

18. php

<? PHP

// Watermark effect.

/*

Function parameters are the same as those of imagecopy,

Difference in the last parameter: $ PCT indicates transparency.

Bool imagecopymerge (resource $ dst_im, resource $ src_im, int $ dst_x, int $ dst_y, int $ src_x, int $ src_y, int $ src_w, int $ src_h, int $ PCT)

*/

$ Big = imagecreatefromjpeg ('./home.jpg ');

$ BX = imagesx ($ big );

$ By = imagesy ($ big );

$ Small = imagecreatefrompng ('./feng.png ');

$ SX = imagesx ($ small );

$ Sy = imagesy ($ small );

// Add text

$ Blue = imagecolorallocate ($ big, 255 );

Imagettftext ($ big, 16, 0, 100,100, $ blue, './msyh. ttf', 'changping water-gun, Fengjie calls you to buy a house ');

Imagecopymerge ($ big, $ small, $ Bx-$ Sx, 0, 0, $ Sx, $ Sy, 37 );

// Output

Header ('content-type: image/JPEG ');

Imagejpeg ($ big );

?>

-------------------

19. php

<? PHP

// Generate a thumbnail

/*

Bool imagecopyresampled (resource $ dst_image, resource $ src_image, int $ dst_x, int $ dst_y, int $ src_x, int $ src_y, int $ dst_w, int $ dst_h, int $ src_w, int $ src_h)

*/

$ Feng = imagecreatefrompng ('./feng.png ');

$ FX = imagesx ($ Feng); // obtain the width.

$ FY = imagesy ($ Feng); // obtain the height

// Create a small canvas

$ SX = $ FX/2;

$ Sy = $ Fy/2;

$ Small = imagecreatetruecolor ($ Sx, $ Sy );

// Stick the large canvas and scale it down.

Imagecopyresampled ($ small, $ Feng, 0, 0, 0, $ Sx, $ Sy, $ FX, $ FY );

If (imagepng ($ small, './xiaofeng.png ')){

Echo 'saved successfully ';

} Else {

Echo 'failed to save ';

}