在EXIF中访问访问Thumbnail.MimeType读取数据

Question

我正在尝试在EXIF的计算头中读取MimeType，但似乎无法找到它，相反，我的循环只是var dumps好像找不到它，但是通过查看vardump时，我可以看到Thumbnail.MimeType确实在计算的标头中，我可能只是想尝试访问它而已，请参见下面的代码，它接受图像上传，然后上传到s3存储桶，然后使用存储桶图像URL获得标头。

$result = $s3->putObject([
    'Bucket' => '*********',
    'Key' => 'full/' . $file_name,
    'SourceFile' => $temp_file_location,
    'ACL' => 'public-read'
]);

$code = $result['@metadata']['statusCode'];
if ($code === 200) {
    $path = "url";
}
$exif_headers = exif_read_data($path, 'EXIF');
$computed_headers = exif_read_data($path, 'COMPUTED');

//check if image has datetime original.
if (!empty($exif_headers['DateTimeOriginal'])) {
    $exif_date = $exif_headers['DateTimeOriginal'];
    echo $exif_date;
} else {
    // if no date time original pull Thumbnail.MimeType.
    if (!empty($computed_headers['Thumbnail.MimeType'])) {
        $exif_mime_type = $computed_headers['Thumbnail.MimeType'];
        echo $exif_mime_type;
    } else { // var dump if Thumbnail.MimeType is empty.
        var_dump($computed_headers);
    }
}

任何帮助将不胜感激:)，我觉得我只是想念某些东西，因为它能够在没有问题的情况下拉起DateTimeOriginal。 TIA

编辑：这是var dump

array(21) { 
    ["FileName"]=> string(67) "5dce8027494055dce756d6bce615ACDD56-0BF6-4754- 
    BA08-C5FD4E0C38EC.jpeg" 
    ["FileDateTime"]=> int(0) 
    ["FileSize"]=> int(1309255) 
    ["FileType"]=> int(2) 
    ["MimeType"]=> string(10) "image/jpeg" 
    ["SectionsFound"]=> string(30) "ANY_TAG, IFD0, THUMBNAIL, EXIF" 

    ["COMPUTED"]=> array(7) { 
    ["html"]=> string(26) "width="3264" height="2448"" 
    ["Height"]=> int(2448) 
    ["Width"]=> int(3264) 
    ["IsColor"]=> int(1) 
    ["ByteOrderMotorola"]=> int(1) 
    ["Thumbnail.FileType"]=> int(2) 
    ["Thumbnail.MimeType"]=> string(10) "image/jpeg" } 
    ["Orientation"]=> int(1) 
    ["XResolution"]=> string(4) "72/1" 
    ["YResolution"]=> string(4) "72/1" 
    ["ResolutionUnit"]=> int(2) 
    ["YCbCrPositioning"]=> int(1) 
    ["Exif_IFD_Pointer"]=> int(102) 


["THUMBNAIL"]=> array(6) { 
    ["Compression"]=> int(6) 
    ["XResolution"]=> string(4) "72/1" 
    ["YResolution"]=> string(4) "72/1" 
    ["ResolutionUnit"]=> int(2) 
    ["JPEGInterchangeFormat"]=> int(286) 
    ["JPEGInterchangeFormatLength"]=> int(7063)
} 

    ["ExifVersion"]=> string(4) "0221" 
    ["ComponentsConfiguration"]=> string(4) "" 
    ["FlashPixVersion"]=> string(4) "0100" 
    ["ColorSpace"]=> int(1) 
    ["ExifImageWidth"]=> int(3264) 
    ["ExifImageLength"]=> int(2448) 
    ["SceneCaptureType"]=> int(0) 
}

Answer 1

如PHP documentation中所述，函数调用exif_read_data（）中的第二个参数表示文件中必须存在以生成结果数组的部分的（逗号分隔）列表。

这并不意味着函数调用将仅返回此部分作为结果！

如下更改代码，它将起作用：

<?php
$result = $s3->putObject([
    'Bucket' => '*********',
    'Key' => 'full/' . $file_name,
    'SourceFile' => $temp_file_location,
    'ACL' => 'public-read'
]);

$code = $result['@metadata']['statusCode'];
if ($code === 200) {
    $path = "url";
}
$exif_data = exif_read_data($path, 'EXIF');
$computed_data = $exif_data['COMPUTED'];

//check if image has datetime original.
if (!empty($exif_data['DateTimeOriginal'])) {
    $exif_date = $exif_data['DateTimeOriginal'];
    echo $exif_date;
} else {
    // if no date time original pull Thumbnail.MimeType.
    if (!empty($computed_data['Thumbnail.MimeType'])) {
        $exif_mime_type = $computed_data['Thumbnail.MimeType'];
        echo $exif_mime_type;
    } else { // var dump if Thumbnail.MimeType is empty.
        var_dump($computed_data);
    }
}
?>