你可以使用以下代码。你需要传递源图像路径和缩略图大小(以像素为单位),可选的目标路径。如果你传递了目标路径,它将保存图像,否则将显示缩略图。
只允许使用jpg、jpeg和png格式的图片。
function cropImage($sourcePath, $thumbSize, $destination = null) {
$parts = explode('.', $sourcePath);
$ext = $parts[count($parts) - 1];
if ($ext == 'jpg' || $ext == 'jpeg') {
$format = 'jpg';
} else {
$format = 'png';
}
if ($format == 'jpg') {
$sourceImage = imagecreatefromjpeg($sourcePath);
}
if ($format == 'png') {
$sourceImage = imagecreatefrompng($sourcePath);
}
list($srcWidth, $srcHeight) = getimagesize($sourcePath);
// calculating the part of the image to use for thumbnail
if ($srcWidth > $srcHeight) {
$y = 0;
$x = ($srcWidth - $srcHeight) / 2;
$smallestSide = $srcHeight;
} else {
$x = 0;
$y = ($srcHeight - $srcWidth) / 2;
$smallestSide = $srcWidth;
}
$destinationImage = imagecreatetruecolor($thumbSize, $thumbSize);
imagecopyresampled($destinationImage, $sourceImage, 0, 0, $x, $y, $thumbSize, $thumbSize, $smallestSide, $smallestSide);
if ($destination == null) {
header('Content-Type: image/jpeg');
if ($format == 'jpg') {
imagejpeg($destinationImage, null, 100);
}
if ($format == 'png') {
imagejpeg($destinationImage);
}
if ($destination = null) {
}
} else {
if ($format == 'jpg') {
imagejpeg($destinationImage, $destination, 100);
}
if ($format == 'png') {
imagepng($destinationImage, $destination);
}
}
}