Question

我需要使用exif_imagetype()来识别图像的文件类型。

这是我的代码：

$imgSrc = "image.jpg";

    if (exif_imagetype($imgSrc) == IMAGETYPE_GIF) {
       $filetype = 'The picture is GIF';
    }
    if (exif_imagetype($imgSrc) == IMAGETYPE_JPEG) {
        $filetype = 'The picture is JPEG';
    }
    if (exif_imagetype($imgSrc) == IMAGETYPE_PNG) {
        $filetype = 'The picture is PNG';
    }
    echo $filetype;

我遇到的问题是$filetype不仅回显了我想要的字符串，而且回显了（我认为是）exif_imagetype()

的完整结果

部分输出：

The picture is JPEG����JFIF��>CREATOR: gd-jpeg v1.0 (using IJG JPEG 
v80), default quality ��C      $.' ",#(7),01444'9=82
<.342��C     2!!22222222222222222222222222222222222222222222222222��

正如你所看到它确实回应了我的字符串，但我不知道为什么其余部分在输出中。

有人能告诉我为什么会这样吗？提前谢谢。

编辑：在下面添加完整的php页面

//getting the image dimensions
list($width, $height) = getimagesize($imgSrc);

    //check file type + saving the image into memory
    if (exif_imagetype($imgSrc) == IMAGETYPE_GIF) {
       $filetype = 'The picture is GIF';
       $myImage = imagecreatefromgif($imgSrc);
    }
    if (exif_imagetype($imgSrc) == IMAGETYPE_JPEG) {
        $filetype = 'The picture is JPEG';
        $myImage = imagecreatefromjpeg($imgSrc);
    }
    if (exif_imagetype($imgSrc) == IMAGETYPE_PNG) {
        $filetype ='The picture is PNG';
        $myImage = imagecreatefrompng($imgSrc);
    }

// calculating the part of the image to use for thumbnail
if ($width > $height) {
  $y = 0;
  $x = ($width - $height) / 2;
  $smallestSide = $height;
} else {
  $x = 0;
  $y = ($height - $width) / 2;
  $smallestSide = $width;
}

//read EXIF header from uploaded file
$exif = exif_read_data($imgSrc);

//fix the Orientation if EXIF data exist
if(!empty($exif['Orientation'])) {
    switch($exif['Orientation']) {
        case 8:
            $myImage = imagerotate($myImage,90,0);
            break;
        case 3:
            $myImage = imagerotate($myImage,180,0);
            break;
        case 6:
            $myImage = imagerotate($myImage,-90,0);
            break;
    }
}

// copying the part into thumbnail
$thumbSize = 200;
$thumb = imagecreatetruecolor($thumbSize, $thumbSize);
imagecopyresampled($thumb, $myImage, 0, 0, $x, $y, $thumbSize, $thumbSize, $smallestSide, $smallestSide);

//final output
header('Content-type: image/jpeg');
imagejpeg($thumb);
?>

if语句中的exif_imagetype（）

0 个答案: