1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
|
/*
* This is public domain software - that is, you can do whatever you want
* with it, and include it software that is licensed under the GNU or the
* BSD license, or whatever other licence you choose, including proprietary
* closed source licenses. I do ask that you leave this header in tact.
*
* If you make modifications to this code that you think would benefit the
* wider community, please send me a copy and I'll post it on my site.
*
* If you make use of this code, I'd appreciate hearing about it.
* drew@drewnoakes.com
* Latest version of this software kept at
* http://drewnoakes.com/
*
* Created by dnoakes on 05-Nov-2002 18:57:14 using IntelliJ IDEA.
*/
package com.drew.metadata;
import com.drew.imaging.jpeg.JpegMetadataReader;
import com.drew.imaging.jpeg.JpegProcessingException;
import com.drew.imaging.jpeg.JpegSegmentReader;
import com.drew.metadata.exif.ExifReader;
import com.drew.metadata.iptc.IptcReader;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.Iterator;
/**
*
*/
public class SampleUsage
{
/**
* Constructor which executes multiple sample usages, each of which return the same output. This class showcases
* multiple usages of this metadata class library.
* @param fileName path to a jpeg file upon which to operate
*/
public SampleUsage(String fileName)
{
File jpegFile = new File(fileName);
// There are multiple ways to get a Metadata object
// Approach 1
// This approach reads all types of known Jpeg metadata (at present,
// Exif and Iptc) in a single call. In most cases, this is the most
// appropriate usage.
try {
Metadata metadata = JpegMetadataReader.readMetadata(jpegFile);
printImageTags(1, metadata);
} catch (JpegProcessingException e) {
System.err.println("error 1a");
}
// Approach 2
// This approach shows using individual MetadataReader implementations
// to read a file. This is less efficient than approach 1, as the file
// is opened and read twice.
try {
Metadata metadata = new Metadata();
new ExifReader(jpegFile).extract(metadata);
new IptcReader(jpegFile).extract(metadata);
printImageTags(2, metadata);
} catch (JpegProcessingException jpe) {
System.err.println("error 2a");
}
// Approach 3
// As fast as approach 1 (this is what goes on inside the JpegMetadataReader's
// readMetadata() method), this code is handy if you want to look into other
// Jpeg segments too.
try {
JpegSegmentReader segmentReader = new JpegSegmentReader(jpegFile);
byte[] exifSegment = segmentReader.readSegment(JpegSegmentReader.SEGMENT_APP1);
byte[] iptcSegment = segmentReader.readSegment(JpegSegmentReader.SEGMENT_APPD);
Metadata metadata = new Metadata();
new ExifReader(exifSegment).extract(metadata);
new IptcReader(iptcSegment).extract(metadata);
printImageTags(3, metadata);
} catch (JpegProcessingException jpe) {
System.err.println("error 3a");
}
}
private void printImageTags(int approachCount, Metadata metadata)
{
System.out.println();
System.out.println("*** APPROACH " + approachCount + " ***");
System.out.println();
// iterate over the exif data and print to System.out
Iterator directories = metadata.getDirectoryIterator();
while (directories.hasNext()) {
Directory directory = (Directory)directories.next();
Iterator tags = directory.getTagIterator();
while (tags.hasNext()) {
Tag tag = (Tag)tags.next();
System.out.println(tag);
}
if (directory.hasErrors()) {
Iterator errors = directory.getErrors();
while (errors.hasNext()) {
System.out.println("ERROR: " + errors.next());
}
}
}
}
/**
* Executes the sample usage program.
* @param args command line parameters
*/
public static void main(String[] args)
{
new SampleUsage("src/com/drew/metadata/test/withIptcExifGps.jpg");
}
}
|
