Uploading pictures on mobile safari changes from vertical to horizontal processing

When uploading a picture in mobile safari, the vertical photo will become a horizontal photo. The following program fragment uses the image exif information to rotate the image back. The code is copied from the php.net official website.

http://php.net/manual/zh/function.exif-read-data.php

<?<span style="color: #000000;">php
</span><span style="color: #800080;">$image</span> = imagecreatefromstring(<span style="color: #008080;">file_get_contents</span>(<span style="color: #800080;">$_FILES</span>['image_upload']['tmp_name'<span style="color: #000000;">]));
</span><span style="color: #800080;">$exif</span> = exif_read_data(<span style="color: #800080;">$_FILES</span>['image_upload']['tmp_name'<span style="color: #000000;">]);
</span><span style="color: #0000ff;">if</span>(!<span style="color: #0000ff;">empty</span>(<span style="color: #800080;">$exif</span>['Orientation'<span style="color: #000000;">])) {
    </span><span style="color: #0000ff;">switch</span>(<span style="color: #800080;">$exif</span>['Orientation'<span style="color: #000000;">]) {
        </span><span style="color: #0000ff;">case</span> 8:
            <span style="color: #800080;">$image</span> = imagerotate(<span style="color: #800080;">$image</span>,90,0<span style="color: #000000;">);
            </span><span style="color: #0000ff;">break</span><span style="color: #000000;">;
        </span><span style="color: #0000ff;">case</span> 3:
            <span style="color: #800080;">$image</span> = imagerotate(<span style="color: #800080;">$image</span>,180,0<span style="color: #000000;">);
            </span><span style="color: #0000ff;">break</span><span style="color: #000000;">;
        </span><span style="color: #0000ff;">case</span> 6:
            <span style="color: #800080;">$image</span> = imagerotate(<span style="color: #800080;">$image</span>,-90,0<span style="color: #000000;">);
            </span><span style="color: #0000ff;">break</span><span style="color: #000000;">;
    }
}
</span><span style="color: #008000;">//以下代码自行处理即可</span>
?>