Get Gif Properties
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
// Revised from apache cocoon
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.BufferedInputStream;
import java.io.FileInputStream;
/**
* @version $Id: ImageUtils.java 587751 2007-10-24 02:41:36Z vgritsenko $
*/
final public class ImageUtils {
final public static ImageProperties getJpegProperties(File file) throws FileNotFoundException, IOException{
BufferedInputStream in = null;
try {
in = new BufferedInputStream(new FileInputStream(file));
// check for "magic" header
byte[] buf = new byte[2];
int count = in.read(buf, 0, 2);
if (count < 2) {
throw new RuntimeException("Not a valid Jpeg file!");
}
if ((buf[0]) != (byte) 0xFF || (buf[1]) != (byte) 0xD8) {
throw new RuntimeException("Not a valid Jpeg file!");
}
int width = 0;
int height = 0;
char[] comment = null;
boolean hasDims = false;
boolean hasComment = false;
int ch = 0;
while (ch != 0xDA && !(hasDims && hasComment)) {
/* Find next marker (JPEG markers begin with 0xFF) */
while (ch != 0xFF) {
ch = in.read();
}
/* JPEG markers can be padded with unlimited 0xFF's */
while (ch == 0xFF) {
ch = in.read();
}
/* Now, ch contains the value of the marker. */
int length = 256 * in.read();
length += in.read();
if (length < 2) {
throw new RuntimeException("Not a valid Jpeg file!");
}
/* Now, length contains the length of the marker. */
if (ch >= 0xC0 && ch <= 0xC3) {
in.read();
height = 256 * in.read();
height += in.read();
width = 256 * in.read();
width += in.read();
for (int foo = 0; foo < length - 2 - 5; foo++) {
in.read();
}
hasDims = true;
}
else if (ch == 0xFE) {
// that's the comment marker
comment = new char[length-2];
for (int foo = 0; foo < length - 2; foo++)
comment[foo] = (char) in.read();
hasComment = true;
}
else {
// just skip marker
for (int foo = 0; foo < length - 2; foo++) {
in.read();
}
}
}
return (new ImageProperties(width, height, comment, "jpeg"));
}
finally {
if (in != null) {
try {
in.close();
}
catch (IOException e) {
}
}
}
}
final public static ImageProperties getGifProperties(File file) throws FileNotFoundException, IOException{
BufferedInputStream in = null;
try {
in = new BufferedInputStream(new FileInputStream(file));
byte[] buf = new byte[10];
int count = in.read(buf, 0, 10);
if (count < 10) {
throw new RuntimeException("Not a valid Gif file!");
}
if ((buf[0]) != (byte) 'G' || (buf[1]) != (byte) 'I' || (buf[2]) != (byte) 'F') {
throw new RuntimeException("Not a valid Gif file!");
}
int w1 = (buf[6] & 0xff) | (buf[6] & 0x80);
int w2 = (buf[7] & 0xff) | (buf[7] & 0x80);
int h1 = (buf[8] & 0xff) | (buf[8] & 0x80);
int h2 = (buf[9] & 0xff) | (buf[9] & 0x80);
int width = w1 + (w2 << 8);
int height = h1 + (h2 << 8);
return (new ImageProperties(width, height, null,"gif"));
}
finally {
if (in != null) {
try {
in.close();
}
catch (IOException e) {
}
}
}
}
}
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* @version $Id: ImageProperties.java 587751 2007-10-24 02:41:36Z vgritsenko $
*/
final class ImageProperties {
final public int width;
final public int height;
final public char[] comment;
final public String type;
public ImageProperties(int width, int height, char[] comment, String type) {
this.width = width;
this.height = height;
this.comment = comment;
this.type = type;
}
public String toString() {
StringBuffer sb = new StringBuffer();
sb.append(type).append(" ").append(width).append("x").append(height);
if (comment != null) {
sb.append(" (").append(comment).append(")");
}
return (sb.toString());
}
}
Related examples in the same category