/*
 * @(#)MJPGImageReaderSpi.java  
 * 
 * Copyright (c) 2010-2011 Werner Randelshofer, Immensee, Switzerland.
 * All rights reserved.
 *
 * You may not use, copy or modify this file, except in compliance with the
 * license agreement you entered into with Werner Randelshofer.
 * For details see accompanying license terms.
 */
package org.monte.media.jmf.jpeg;

import java.io.IOException;
import java.io.InputStream;
import java.util.Locale;
import javax.imageio.ImageReader;
import javax.imageio.spi.ImageReaderSpi;
import javax.imageio.stream.ImageInputStream;


/**
 * ImageIO service provider interface for images in the Motion JPEG (MJPG)
 * format.
 * <p>
 * The reader described by this class can read Motion JPEG files with omitted
 * Huffmann table.
 * <p>
 * For more information see:
 * Microsoft Windows Bitmap Format.
 * Multimedia Technical Note: JPEG DIB Format.
 * (c) 1993 Microsoft Corporation. All rights reserved.
 * <a href="http://www.fileformat.info/format/bmp/spec/b7c72ebab8064da48ae5ed0c053c67a4/BMPDIB.TXT">BMPDIB.txt</a>

 *
 * @author Werner Randelshofer
 * @version $Id: MJPGImageReaderSpi.java 140 2011-12-31 14:33:52Z werner $
 */
public class MJPGImageReaderSpi extends ImageReaderSpi {

    public MJPGImageReaderSpi() {
        super("Werner Randelshofer",//vendor name
                "1.0",//version
                new String[]{"MJPG"},//names
                new String[]{"mjpg"},//suffixes,
                new String[]{"image/mjpg"},// MIMETypes,
                "org.monte.media.jmf.renderer.video.MJPGImageReader",// readerClassName,
                new Class[]{ImageInputStream.class,InputStream.class,byte[].class,javax.media.Buffer.class},// inputTypes,
                null,// writerSpiNames,
                false,// supportsStandardStreamMetadataFormat,
                null,// nativeStreamMetadataFormatName,
                null,// nativeStreamMetadataFormatClassName,
                null,// extraStreamMetadataFormatNames,
                null,// extraStreamMetadataFormatClassNames,
                false,// supportsStandardImageMetadataFormat,
                null,// nativeImageMetadataFormatName,
                null,// nativeImageMetadataFormatClassName,
                null,// extraImageMetadataFormatNames,
                null// extraImageMetadataFormatClassNames
                );
    }

    @Override
    public boolean canDecodeInput(Object source) throws IOException {
        if (source instanceof ImageInputStream) {
            ImageInputStream in = (ImageInputStream) source;
            in.mark();

            // Check if file starts with a JFIF SOI magic (0xffd8=-40)
            if (in.readShort() != -40) {
                in.reset();
                return false;
            }
            in.reset();
            return true;
        }
        return false;
    }

    @Override
    public ImageReader createReaderInstance(Object extension) throws IOException {
        return new MJPGImageReader(this);
    }

    @Override
    public String getDescription(Locale locale) {
        return "MJPG Image Reader";
    }
}
