Home | History | Annotate | Download | only in jpeg 
      1 /*
      2  *  Licensed to the Apache Software Foundation (ASF) under one or more
      3  *  contributor license agreements.  See the NOTICE file distributed with
      4  *  this work for additional information regarding copyright ownership.
      5  *  The ASF licenses this file to You under the Apache License, Version 2.0
      6  *  (the "License"); you may not use this file except in compliance with
      7  *  the License.  You may obtain a copy of the License at
      8  *
      9  *     http://www.apache.org/licenses/LICENSE-2.0
     10  *
     11  *  Unless required by applicable law or agreed to in writing, software
     12  *  distributed under the License is distributed on an "AS IS" BASIS,
     13  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     14  *  See the License for the specific language governing permissions and
     15  *  limitations under the License.
     16  */
     17 /**
     18  * @author Rustem V. Rafikov
     19  * @version $Revision: 1.3 $
     20  */
     21 package org.apache.harmony.x.imageio.plugins.jpeg;
     22 
     23 import java.io.IOException;
     24 import java.util.Locale;
     25 import javax.imageio.ImageReader;
     26 import javax.imageio.spi.ImageReaderSpi;
     27 import javax.imageio.spi.ServiceRegistry;
     28 import javax.imageio.stream.ImageInputStream;
     29 
     30 public class JPEGImageReaderSpi extends ImageReaderSpi {
     31 
     32     public JPEGImageReaderSpi() {
     33         super(JPEGSpiConsts.vendorName, JPEGSpiConsts.version,
     34                 JPEGSpiConsts.names, JPEGSpiConsts.suffixes,
     35                 JPEGSpiConsts.MIMETypes, JPEGSpiConsts.readerClassName,
     36                 STANDARD_INPUT_TYPE, JPEGSpiConsts.writerSpiNames,
     37                 JPEGSpiConsts.supportsStandardStreamMetadataFormat,
     38                 JPEGSpiConsts.nativeStreamMetadataFormatName,
     39                 JPEGSpiConsts.nativeStreamMetadataFormatClassName,
     40                 JPEGSpiConsts.extraStreamMetadataFormatNames,
     41                 JPEGSpiConsts.extraStreamMetadataFormatClassNames,
     42                 JPEGSpiConsts.supportsStandardImageMetadataFormat,
     43                 JPEGSpiConsts.nativeImageMetadataFormatName,
     44                 JPEGSpiConsts.nativeImageMetadataFormatClassName,
     45                 JPEGSpiConsts.extraImageMetadataFormatNames,
     46                 JPEGSpiConsts.extraImageMetadataFormatClassNames);
     47     }
     48 
     49 
     50     @Override
     51     public boolean canDecodeInput(Object source) throws IOException {
     52         ImageInputStream markable = (ImageInputStream) source;
     53         try {
     54             markable.mark();
     55 
     56             byte[] signature = new byte[3];
     57             markable.seek(0);
     58             markable.read(signature, 0, 3);
     59             markable.reset();
     60 
     61             if ((signature[0] & 0xFF) == 0xFF &&
     62                     (signature[1] & 0xFF) == JPEGConsts.SOI &&
     63                     (signature[2] & 0xFF) == 0xFF) { // JPEG
     64                 return true;
     65             }
     66         } catch (IOException e) {
     67             e.printStackTrace();
     68         }
     69         return false;
     70     }
     71 
     72     @Override
     73     public ImageReader createReaderInstance(Object extension) throws IOException {
     74         return new JPEGImageReader(this);
     75     }
     76 
     77     @Override
     78     public String getDescription(Locale locale) {
     79         return "DRL JPEG decoder";
     80     }
     81 
     82     @Override
     83     public void onRegistration(ServiceRegistry registry, Class<?> category) {
     84         // super.onRegistration(registry, category);
     85     }
     86 }
     87