PHP は適応サイズのサムネイル クラスを生成し、その使用法を共有します_PHP チュートリアル
- WBOYオリジナル
- 2016-07-13 10:30:27876ブラウズ
次のコードを直接コピーして、thumbnailimage.php という名前の新しいファイルを作成します。ファイル名には大文字を使用しないことをお勧めします。
define ( 'MAX_IMG_SIZE', 100000 );
// Supported image types
define ( 'THUMB_JPEG', 'image/jpeg' );
define ( 'THUMB_PNG', 'image/png' );
define ( 'THUMB_GIF', 'image/gif' );
// Interlacing modes
define ( 'INTERLACE_OFF', 0 );
define ( 'INTERLACE_ON', 1 );
// Output modes
define ( 'STDOUT', '' );
// Empty constants
define ( 'NO_LOGO', '' );
define ( 'NO_LABEL', '' );
// Logo and label positioning
define ( 'POS_LEFT', 0 );
define ( 'POS_RIGHT', 1 );
define ( 'POS_CENTER', 2 );
define ( 'POS_TOP', 3 );
define ( 'POS_BOTTOM', 4 );
// Error messages
define ( 'E_001', 'File %s do not exist' );
define ( 'E_002', 'Failed reading image data from %s' );
define ( 'E_003', 'Cannot create the copy of %s' );
define ( 'E_004', 'Cannot copy the logo image' );
define ( 'E_005', 'Cannot create final image' );
// ****************************************************************************
// CLASS DEFINITION
// ****************************************************************************
class ThumbnailImage
{
// ****************************************************************************
// PUBLIC PROPERTIES
// ****************************************************************************
var $src_file; // source image file
var $dest_file; // destination image file
var $dest_type; // destination image type
var $interlace; // destination image interlacing mode
var $jpeg_quality; // quality of resulting JPEG
var $max_width; // maximal thumbnail width
var $max_height; // maximal thumbnail height
var $fit_to_max; // enlarge small images?
var $logo; // array of logo parameters
var $label; // array of label parameters
// ****************************************************************************
// CLASS CONSTRUCTOR
// ****************************************************************************
/*
Description:
Defines default values for properties.
Prototype:
void ThumbImg ( string src_file = '' )
Parameters:
src_file - source image filename
*/
function ThumbnailImage ( $src_file = '' )
{
$this->src_file = $src_file;
$this->dest_file = STDOUT;
$this->dest_type = THUMB_JPEG;
$this->interlace = INTERLACE_OFF;
$this->jpeg_quality = -1;
$this->max_width = 100;
$this->max_height = 90;
$this->fit_to_max = FALSE;
$this->logo['file'] = NO_LOGO;
$this->logo['vert_pos'] = POS_TOP;
$this->logo['horz_pos'] = POS_LEFT;
$this->label['text'] = NO_LABEL;
$this->label['vert_pos'] = POS_BOTTOM;
$this->label['horz_pos'] = POS_RIGHT;
$this->label['font'] = '';
$this->label['size'] = 20;
$this->label['color'] = '#000000';
$this->label['angle'] = 0;
}
// ****************************************************************************
// PRIVATE METHODS
// ****************************************************************************
/*
Description:
Extracts decimal color components from hex color string.
Prototype:
array ParseColor ( string hex_color )
Parameters:
hex_color - color in '#rrggbb' format
Return:
Decimal values for red, green and blue color components.
*/
function ParseColor ( $hex_color )
{
if ( strpos ( $hex_color, '#' ) === 0 )
$hex_color = substr ( $hex_color, 1 );
$r = hexdec ( substr ( $hex_color, 0, 2 ) );
$g = hexdec ( substr ( $hex_color, 2, 2 ) );
$b = hexdec ( substr ( $hex_color, 4, 2 ) );
return array ( $r, $g, $b );
}
/*
Description:
Retrives image data as a string.
Thanks to Luis Larrateguy for the idea of this function.
Prototype:
string GetImageStr ( string image_file )
Parameters:
image_file - filename of image
Return:
Image file contents string.
*/
function GetImageStr ( $image_file )
{
if ( function_exists ( 'file_get_contents' ) )
{
$str = @file_get_contents ( $image_file );
if ( ! $str )
{
$err = sprintf( E_002, $image_file );
trigger_error( $err, E_USER_ERROR );
}
return $str;
}
$f = fopen ( $image_file, 'rb' );
if ( ! $f )
{
$err = sprintf( E_002, $image_file );
trigger_error( $err, E_USER_ERROR );
}
$fsz = @filesize ( $image_file );
if ( ! $fsz )
$fsz = MAX_IMG_SIZE;
$str = fread ( $f, $fsz );
fclose ( $f );
return $str;
}
/*
Description:
Loads image from file.
Prototype:
resource LoadImage ( string image_file, int &image_width, int &image_height )
Parameters:
image_file - filename of image
image_width - width of loaded image
image_height - height of loaded image
Return:
Image identifier representing the image obtained from the given file.
*/
function LoadImage ( $image_file, &$image_width, &$image_height )
{
$image_width = 0;
$image_height = 0;
$image_data = $this->GetImageStr( $image_file );
$image = imagecreatefromstring ( $image_data );
if ( ! $image )
{
$err = sprintf( E_003, $image_file );
trigger_error( $err, E_USER_ERROR );
}
$image_width = imagesx ( $image );
$image_height = imagesy ( $image );
return $image;
}
/*
Description:
Calculates thumbnail image sizes from source image width and height.
Prototype:
array GetThumbSize ( int src_width, int src_height )
Parameters:
src_width - width of source image
src_height - height of source image
Return:
An array with 2 elements. Index 0 contains the width of thumbnail image
and index 1 contains the height.
*/
function GetThumbSize ( $src_width, $src_height )
{
$max_width = $this->max_width;
$max_height = $this->max_height;
$x_ratio = $max_width / $src_width;
$y_ratio = $max_height / $src_height;
$is_small = ( $src_width <= $max_width && $src_height <= $max_height );
if ( ! $this->fit_to_max && $is_small )
{
$dest_width = $src_width;
$dest_height = $src_height;
}
elseif ( $x_ratio * $src_height < $max_height )
{
$dest_width = $max_width;
$dest_height = ceil ( $x_ratio * $src_height );
}
else
{
$dest_width = ceil ( $y_ratio * $src_width );
$dest_height = $max_height;
}
return array ( $dest_width, $dest_height );
}
/*
Description:
Adds logo image to thumbnail.
Prototype:
void AddLogo ( int thumb_width, int thumb_height, resource &thumb_img )
Parameters:
thumb_width - width of thumbnail image
thumb_height - height of thumbnail image
thumb_img - thumbnail image identifier
*/
function AddLogo ( $thumb_width, $thumb_height, &$thumb_img )
{
extract ( $this->logo );
$logo_image = $this->LoadImage ( $file, $logo_width, $logo_height );
if ( $vert_pos == POS_CENTER )
$y_pos = ceil ( $thumb_height / 2 - $logo_height / 2 );
elseif ($vert_pos == POS_BOTTOM)
$y_pos = $thumb_height - $logo_height;
else
$y_pos = 0;
if ( $horz_pos == POS_CENTER )
$x_pos = ceil ( $thumb_width / 2 - $logo_width / 2 );
elseif ( $horz_pos == POS_RIGHT )
$x_pos = $thumb_width - $logo_width;
else
$x_pos = 0;
if ( ! imagecopy ( $thumb_img, $logo_image, $x_pos, $y_pos, 0, 0,
$logo_width, $logo_height ) )
trigger_error( E_004, E_USER_ERROR );
}
/*
Description:
Adds label text to thumbnail.
Prototype:
void AddLabel ( int thumb_width, int thumb_height, resource &thumb_img )
Parameters:
thumb_width - width of thumbnail image
thumb_height - height of thumbnail image
thumb_img - thumbnail image identifier
*/
function AddLabel ( $thumb_width, $thumb_height, &$thumb_img )
{
extract ( $this->label );
list( $r, $g, $b ) = $this->ParseColor ( $color );
$color_id = imagecolorallocate ( $thumb_img, $r, $g, $b );
$text_box = imagettfbbox ( $size, $angle, $font, $text );
$text_width = $text_box [ 2 ] - $text_box [ 0 ];
$text_height = abs ( $text_box [ 1 ] - $text_box [ 7 ] );
if ( $vert_pos == POS_TOP )
$y_pos = 5 + $text_height;
elseif ( $vert_pos == POS_CENTER )
$y_pos = ceil( $thumb_height / 2 - $text_height / 2 );
elseif ( $vert_pos == POS_BOTTOM )
$y_pos = $thumb_height - $text_height;
if ( $horz_pos == POS_LEFT )
$x_pos = 5;
elseif ( $horz_pos == POS_CENTER )
$x_pos = ceil( $thumb_width / 2 - $text_width / 2 );
elseif ( $horz_pos == POS_RIGHT )
$x_pos = $thumb_width - $text_width -5;
imagettftext ( $thumb_img, $size, $angle, $x_pos, $y_pos,
$color_id, $font, $text );
}
/*
Description:
Output thumbnail image into the browser.
Prototype:
void OutputThumbImage ( resource dest_image )
Parameters:
dest_img - thumbnail image identifier
*/
function OutputThumbImage ( $dest_image )
{
imageinterlace ( $dest_image, $this->interlace );
header ( 'Content-type: ' . $this->dest_type );
if ( $this->dest_type == THUMB_JPEG )
imagejpeg ( $dest_image, '', $this->jpeg_quality );
elseif ( $this->dest_type == THUMB_GIF )
imagegif($dest_image);
elseif ( $this->dest_type == THUMB_PNG )
imagepng ( $dest_image );
}
/*
説明:
サムネイル画像をディスクファイルに保存します。
プロトタイプ:
void SaveThumbImage ( string image_file, resource dest_image )
パラメータ:
image_file - 保存先ファイル名
dest_img - サムネイル画像識別子
*/
function SaveThumbImage ( $image_file, $dest_image )
{
imageinterlace ( $dest_image, $this->interlace );
if ( $this->dest_type == THUMB_JPEG )
imagejpeg ( $dest_image, $this->dest_file, $this->jpeg_quality );
elseif ( $this->dest_type == THUMB_GIF )
imagegif ( $dest_image, $this->dest_file );
elseif ( $this->dest_type == THUMB_PNG )
imagepng ( $dest_image, $this->dest_file );
}
// ********************************************** *******************************
// パブリックメソッド
// ************* ************************************************* *************
/*
説明:
パラメータの
値に従って、ブラウザまたはディスクファイルにサムネイル画像を出力します。
プロトタイプ:
void Output ( )
*/
function Output()
{
$src_image = $this->LoadImage($this->src_file, $src_width, $src_height);
$dest_size = $this->GetThumbSize($src_width, $src_height);
$dest_width=$dest_size[0];
$dest_height=$dest_size[1];
$dest_image=imagecreatetruecolor($dest_width, $dest_height);
if (!$dest_image)
trigger_error(E_005, E_USER_ERROR);
imagecopyresampled( $dest_image, $src_image, 0, 0, 0, 0,
$dest_width, $dest_height, $src_width, $src_height );
if ($this->logo['file'] != NO_LOGO)
$this->AddLogo($dest_width, $dest_height, $dest_image);
if ($this->label['text'] != NO_LABEL)
$this->AddLabel($dest_width, $dest_height, $dest_image);
if ($this->dest_file == STDOUT)
$this->OutputThumbImage ( $dest_image );
else
$this->SaveThumbImage ( $this->dest_file, $dest_image );
imagedestroy ( $src_image );
imagedestroy ( $dest_image );
}
} // クラス定義の終了
?>
使用方法：
1、最初引用该php文件（不要告诉我不会）
2、调用代码
$tis = new ThumbnailImage( );
$tis->src_file = "这里写源文件の経路"
$tis->dest_type = THUMB_JPEG;// 生成される画像の種類は jpg
$tis->dest_file = '这里写目文件の経路';
$tis->max_width = 120;//自适应大小、ただし最大宽度は120
$tis->max_height = 4000; //自适应大小、ただし最大高さは 4000
$tis->Output();
ペイジコードは、max_width と max_height の範囲内で、どのような大きさであっても、差分が大きくないファイルを生成することを可能にし、一般に、非転送の画像には、長さなどの性質があり、短い画像が生成されるかどうかも独自のものであると考えられます。
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