/*
* Copyright 2002-2012 Drew Noakes
*
* Licensed 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.
*
* More information about this project is available at:
*
* http://drewnoakes.com/code/exif/
* http://code.google.com/p/metadata-extractor/
*/
package com.drew.metadata.adobe;
import com.drew.lang.BufferBoundsException;
import com.drew.lang.BufferReader;
import com.drew.lang.annotations.NotNull;
import com.drew.metadata.Directory;
import com.drew.metadata.Metadata;
import com.drew.metadata.MetadataReader;
/**
* Decodes Adobe formatted data stored in JPEG files, normally in the APPE (App14) segment.
*
* @author Philip, Drew Noakes http://drewnoakes.com
*/
public class AdobeJpegReader implements MetadataReader
{
public void extract(@NotNull final BufferReader reader, @NotNull Metadata metadata)
{
final Directory directory = metadata.getOrCreateDirectory(AdobeJpegDirectory.class);
if (reader.getLength() != 12) {
directory.addError(String.format("Adobe JPEG data is expected to be 12 bytes long, not %d.", reader.getLength()));
return;
}
try {
reader.setMotorolaByteOrder(false);
if (!reader.getString(0, 5).equals("Adobe")) {
directory.addError("Invalid Adobe JPEG data header.");
return;
}
directory.setInt(AdobeJpegDirectory.TAG_DCT_ENCODE_VERSION, reader.getUInt16(5));
directory.setInt(AdobeJpegDirectory.TAG_APP14_FLAGS0, reader.getUInt16(7));
directory.setInt(AdobeJpegDirectory.TAG_APP14_FLAGS1, reader.getUInt16(9));
directory.setInt(AdobeJpegDirectory.TAG_COLOR_TRANSFORM, reader.getInt8(11));
} catch (BufferBoundsException ex) {
directory.addError("Exif data segment ended prematurely");
}
}
}