read_exif_data未显示正确的数据

Question

我正在使用read_exif_data函数来获取有关上传图片的详细信息，但在某些情况下，数据无法正确显示。 我正在分享分辨率显示小于1的图像的输出

Array
(
[FileName] => 1444195025.jpg
[FileDateTime] => 1444195025
[FileSize] => 1777209
[FileType] => 2
[MimeType] => image/jpeg
[SectionsFound] => ANY_TAG, IFD0, THUMBNAIL, EXIF
[COMPUTED] => Array
    (
        [html] => width="1893" height="1494"
        [Height] => 1494
        [Width] => 1893
        [IsColor] => 1
        [ByteOrderMotorola] => 0
        [Copyright] =>

    )

[ImageWidth] => 1893
[ImageLength] => 1494
[BitsPerSample] => 8
[Compression] => 1
[PhotometricInterpretation] => 1
[ImageDescription] =>
[Orientation] => 1
[SamplesPerPixel] => 1
**[XResolution] => 1/316
[YResolution] => 372/283465**
[ResolutionUnit] => 3
[Software] => '
[DateTime] => 5.1 Windows
[Artist] => 03 23:26:03
[Copyright] =>
[Exif_IFD_Pointer] => 316
[THUMBNAIL] => Array
    (
        [Compression] => 6
        [XResolution] => 72/1
        [YResolution] => 72/1
        [ResolutionUnit] => 2
        [JPEGInterchangeFormat] => 466
        [JPEGInterchangeFormatLength] => 8382
    )

[ExifVersion] => 0221
[ColorSpace] => 1
[ExifImageWidth] => 1893
[ExifImageLength] => 1494
 )

我对图片如何resolution less then 1而图片大小约为1.8 MB感到困惑。我正在使用codeigniter框架。