Photo

PHP memiliki kemampuan membaca image / gambar. Dengan kemampuan itu tentu saja PHP mampu membaca data-data asal yang terdapat dalam image tersebut. Biasanya data tersebut dinamakan metadata. Proses pembacaan metadata itu cukup mudah, yaitu dengan memanfaatkan fungsi exif_read_data(). Misal saya memiliki sebuah gambar berekstensi JPEG dengan nama satu.JPEG, yang berasal dari hasil jepretan kamera digital. Maka data asal dari gambar tersebut dapat dibaca dengan perintah berikut :

$data = exif_read_data('images/satu.jpg');
echo "< pre >";
print_r( $data );
echo "

$data = exif_read_data('images/satu.jpg');

echo "< pre >";

print_r( $data );

echo "

“;

Data yang muncul kira-kira seperti berikut:

Array
(
    [FileName] => satu.jpg
    [FileDateTime] => 1335936620
    [FileSize] => 5441417
    [FileType] => 2
    [MimeType] => image/jpeg
    [SectionsFound] => ANY_TAG, IFD0, THUMBNAIL, EXIF, INTEROP
    [COMPUTED] => Array
        (
            [html] => width="4320" height="3240"
            [Height] => 3240
            [Width] => 4320
            [IsColor] => 1
            [ByteOrderMotorola] => 0
            [ApertureFNumber] => f/2.9
            [UserComment] => 
            [UserCommentEncoding] => UNDEFINED
            [Copyright] => Copyright 2010
            [Thumbnail.FileType] => 2
            [Thumbnail.MimeType] => image/jpeg
        )

    [ImageDescription] => 
    [Make] => BenQ Corporation
    [Model] => DC C143X
    [Orientation] => 1
    [XResolution] => 288/3
    [YResolution] => 288/3
    [ResolutionUnit] => 2
    [Software] => 1.7600
    [DateTime] => 2012:05:02 12:30:21
    [YCbCrPositioning] => 2
    [Copyright] => Copyright 2010
    [Exif_IFD_Pointer] => 322
    [THUMBNAIL] => Array
        (
            [Compression] => 6
            [Orientation] => 1
            [XResolution] => 72/1
            [YResolution] => 72/1
            [ResolutionUnit] => 2
            [JPEGInterchangeFormat] => 4290
            [JPEGInterchangeFormatLength] => 7287
            [YCbCrPositioning] => 2
        )

    [ExposureTime] => 1/279
    [FNumber] => 29/10
    [ExposureProgram] => 2
    [ISOSpeedRatings] => 100
    [ExifVersion] => 0220
    [DateTimeOriginal] => 2012:05:02 12:30:21
    [DateTimeDigitized] => 2012:05:02 12:30:21
    [ComponentsConfiguration] => �
    [CompressedBitsPerPixel] => 500/100
    [ShutterSpeedValue] => 8124/1000
    [ApertureValue] => 3071/1000
    [ExposureBiasValue] => 0/100
    [MaxApertureValue] => 3171/1000
    [MeteringMode] => 4
    [LightSource] => 0
    [Flash] => 24
    [FocalLength] => 6300/1000
    [MakerNote] => 
IP1:1 exp 130 agc: 95 cal_agc : 128 P2C : 16
.
.
.

Array

(

[FileName] => satu.jpg

[FileDateTime] => 1335936620

[FileSize] => 5441417

[FileType] => 2

[MimeType] => image/jpeg

[SectionsFound] => ANY_TAG, IFD0, THUMBNAIL, EXIF, INTEROP

[COMPUTED] => Array

(

[html] => width="4320" height="3240"

[Height] => 3240

[Width] => 4320

[IsColor] => 1

[ByteOrderMotorola] => 0

[ApertureFNumber] => f/2.9

[UserComment] =>

[UserCommentEncoding] => UNDEFINED

[Thumbnail.FileType] => 2

[Thumbnail.MimeType] => image/jpeg

)

[ImageDescription] =>

[Make] => BenQ Corporation

[Model] => DC C143X

[Orientation] => 1

[XResolution] => 288/3

[YResolution] => 288/3

[ResolutionUnit] => 2

[Software] => 1.7600

[DateTime] => 2012:05:02 12:30:21

[YCbCrPositioning] => 2

[Exif_IFD_Pointer] => 322

[THUMBNAIL] => Array

(

[Compression] => 6

[Orientation] => 1

[XResolution] => 72/1

[YResolution] => 72/1

[ResolutionUnit] => 2

[JPEGInterchangeFormat] => 4290

[JPEGInterchangeFormatLength] => 7287

[YCbCrPositioning] => 2

)

[ExposureTime] => 1/279

[FNumber] => 29/10

[ExposureProgram] => 2

[ISOSpeedRatings] => 100

[ExifVersion] => 0220

[DateTimeOriginal] => 2012:05:02 12:30:21

[DateTimeDigitized] => 2012:05:02 12:30:21

[ComponentsConfiguration] => �

[CompressedBitsPerPixel] => 500/100

[ShutterSpeedValue] => 8124/1000

[ApertureValue] => 3071/1000

[ExposureBiasValue] => 0/100

[MaxApertureValue] => 3171/1000

[MeteringMode] => 4

[LightSource] => 0

[Flash] => 24

[FocalLength] => 6300/1000

[MakerNote] =>

IP1:1 exp 130 agc: 95 cal_agc : 128 P2C : 16

dan seterusnya. Hanya diambil sebagian karena cukup panjang. Pada bagian tersebut terlihat hampir semua properti pembuatan gambar tersebut. Antara lain dibuat kapan, dengan menggunakan kamera apa, ukuran berapa. Untuk keperluan programming biasanya hasil ini akan diatur dengan penguraian array lanjut. Antara lain kira-kira seperti berikut:

$data = exif_read_data('images/satu.jpg');
foreach($data as $key=>$val) {
    if(is_array($val)) {
        foreach($val as $k=>$v) {
            echo $key."[$k]: $v<br />\n";
        }
    } else
        echo "$key: ".@substr($val,0,40)."<br />\n";
}

$data = exif_read_data('images/satu.jpg');

foreach($data as $key=>$val) {

if(is_array($val)) {

foreach($val as $k=>$v) {

echo $key."[$k]: $v<br />\n";

}

} else

echo "$key: ".@substr($val,0,40)."<br />\n";

}

Hasilnya kira-kira akan seperti berikut:

FileName: IMG_0495.JPG

FileDateTime: 1335936620

FileSize: 5441417

FileType: 2

MimeType: image/jpeg

SectionsFound: ANY_TAG, IFD0, THUMBNAIL, EXIF, INTEROP

COMPUTED[html]: width="4320" height="3240"

COMPUTED[Height]: 3240

COMPUTED[Width]: 4320

COMPUTED[IsColor]: 1

COMPUTED[ByteOrderMotorola]: 0

COMPUTED[ApertureFNumber]: f/2.9

COMPUTED[UserComment]: 

COMPUTED[UserCommentEncoding]: UNDEFINED

COMPUTED[Copyright]: Copyright 2010

COMPUTED[Thumbnail.FileType]: 2

COMPUTED[Thumbnail.MimeType]: image/jpeg

ImageDescription: 

Make: BenQ Corporation

Model: DC C143X

Orientation: 1

XResolution: 288/3

YResolution: 288/3

ResolutionUnit: 2

Software: 1.7600

DateTime: 2012:05:02 12:30:21

YCbCrPositioning: 2

Copyright: Copyright 2010

Exif_IFD_Pointer: 322

THUMBNAIL[Compression]: 6

THUMBNAIL[Orientation]: 1

THUMBNAIL[XResolution]: 72/1

THUMBNAIL[YResolution]: 72/1

THUMBNAIL[ResolutionUnit]: 2

THUMBNAIL[JPEGInterchangeFormat]: 4290

THUMBNAIL[JPEGInterchangeFormatLength]: 7287

THUMBNAIL[YCbCrPositioning]: 2

ExposureTime: 1/279

FNumber: 29/10

ExposureProgram: 2

ISOSpeedRatings: 100

ExifVersion: 0220

DateTimeOriginal: 2012:05:02 12:30:21

DateTimeDigitized: 2012:05:02 12:30:21

ComponentsConfiguration: �

CompressedBitsPerPixel: 500/100

ShutterSpeedValue: 8124/1000

ApertureValue: 3071/1000

ExposureBiasValue: 0/100

MaxApertureValue: 3171/1000

MeteringMode: 4

LightSource: 0

Flash: 24

FocalLength: 6300/1000

MakerNote: 
IP1:1 exp 130 agc: 95 cal_agc : 128 P2C

UserComment: ����������������������������������������

SubSecTime: 0�

FlashPixVersion: 0100

ColorSpace: 1

ExifImageWidth: 4320

ExifImageLength: 3240

RelatedSoundFile: 

InteroperabilityOffset: 4260

FileSource: 

SceneType: 

ExposureMode: 0

WhiteBalance: 0

DigitalZoomRatio: 100/100

FocalLengthIn35mmFilm: 36

SceneCaptureType: 33

Contrast: 0

Saturation: 0

Sharpness: 0

InterOperabilityIndex: R98

InterOperabilityVersion: 0100

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

FileName: IMG_0495.JPG

FileDateTime: 1335936620

FileSize: 5441417

FileType: 2

MimeType: image/jpeg

SectionsFound: ANY_TAG, IFD0, THUMBNAIL, EXIF, INTEROP

COMPUTED[html]: width="4320" height="3240"

COMPUTED[Height]: 3240

COMPUTED[Width]: 4320

COMPUTED[IsColor]: 1

COMPUTED[ByteOrderMotorola]: 0

COMPUTED[ApertureFNumber]: f/2.9

COMPUTED[UserComment]:

COMPUTED[UserCommentEncoding]: UNDEFINED

COMPUTED[Thumbnail.FileType]: 2

COMPUTED[Thumbnail.MimeType]: image/jpeg

ImageDescription:

Make: BenQ Corporation

Model: DC C143X

Orientation: 1

XResolution: 288/3

YResolution: 288/3

ResolutionUnit: 2

Software: 1.7600

DateTime: 2012:05:02 12:30:21

YCbCrPositioning: 2

Exif_IFD_Pointer: 322

THUMBNAIL[Compression]: 6

THUMBNAIL[Orientation]: 1

THUMBNAIL[XResolution]: 72/1

THUMBNAIL[YResolution]: 72/1

THUMBNAIL[ResolutionUnit]: 2

THUMBNAIL[JPEGInterchangeFormat]: 4290

THUMBNAIL[JPEGInterchangeFormatLength]: 7287

THUMBNAIL[YCbCrPositioning]: 2

ExposureTime: 1/279

FNumber: 29/10

ExposureProgram: 2

ISOSpeedRatings: 100

ExifVersion: 0220

DateTimeOriginal: 2012:05:02 12:30:21

DateTimeDigitized: 2012:05:02 12:30:21

ComponentsConfiguration: �

CompressedBitsPerPixel: 500/100

ShutterSpeedValue: 8124/1000

ApertureValue: 3071/1000

ExposureBiasValue: 0/100

MaxApertureValue: 3171/1000

MeteringMode: 4

LightSource: 0

Flash: 24

FocalLength: 6300/1000

MakerNote:

IP1:1 exp 130 agc: 95 cal_agc : 128 P2C

UserComment: ��

SubSecTime: 0�

FlashPixVersion: 0100

ColorSpace: 1

ExifImageWidth: 4320

ExifImageLength: 3240

RelatedSoundFile:

InteroperabilityOffset: 4260

FileSource:

SceneType:

ExposureMode: 0

WhiteBalance: 0

DigitalZoomRatio: 100/100

FocalLengthIn35mmFilm: 36

SceneCaptureType: 33

Contrast: 0

Saturation: 0

Sharpness: 0

InterOperabilityIndex: R98

InterOperabilityVersion: 0100

Dengan demikian, sebenarnya situs-situs fotografi, atau lomba fotografi akan dapat mengetahui bahwa sebenarnya gambar tersebut asli atau sudah ter-edit oleh software lain seperti potoshop dan lain sebagainya, meski ternyata metadata ini juga dapat dilakukan editing, yang akan kita pelajari dalam section lain. Ada yang berminat menjadi roy suryo moderen sebagai ahli metadata?? Silakan belajar lebih lanjut . Untuk exif_read_data, hanya dapat digunakan jenis file JPG dan TIFF. Anda juga dapat mengkombinasikan dengan form upload file.

Sekian, semoga bermanfaat

Catatan buruh IT

[Tips] Membaca Metadata Image JPEG/TIFF dengan PHP

Artikel terkait