exif_thumbnail
(PHP 4 >= 4.2.0, PHP 5)
exif_thumbnail — 取得嵌入在 TIFF 或 JPEG 图像中的缩略图
说明
string exif_thumbnail ( string $filename [, int &$width [, int &$height [, int &$imagetype ]]] )exif_thumbnail() 读取 TIFF 或 JPEG 图像中的嵌入缩略图。如果图像不包含缩略图则返回 FALSE。
If you want to deliver thumbnails through this function, you should send the mimetype information using the header() function.
It is possible that exif_thumbnail() cannot create an image but can determine its size. In this case, the return value is FALSE but width and height are set.
参数
- filename
-
The name of the image file being read. This image contains an embedded thumbnail.
- width
-
The return width of the returned thumbnail.
- height
-
The returned height of the returned thumbnail.
- imagetype
-
The returned image type of the returned thumbnail. This is either TIFF or JPEG.
返回值
Returns the embedded thumbnail, or FALSE if the image contains no thumbnail.
更新日志
| 版本 | 说明 |
|---|---|
| 4.3.0 | The optional parameters width, height, and imagetype all became available. |
| 4.3.0 | May return thumbnails in the TIFF format. |
范例
Example #1 exif_thumbnail() 例子
<?php
if (array_key_exists('file',$_REQUEST)) {
$image = exif_thumbnail($_REQUEST['file'], $width, $height, $type);
} else {
$image = false;
}
if ($image!==false) {
header("Content-type: ".image_type_to_mime_type($type));
echo $image;
exit;
} else {
// no thumbnail available, handle the error here
echo "No thumbnail available";
}
?>
参见
- exif_read_data() - 从 JPEG 或 TIFF 文件中读取 EXIF 头信息
- image_type_to_mime_type() - 取得 getimagesize，exif_read_data，exif_thumbnail，exif_imagetype 所返回的图像类型的 MIME 类型
