snappermidlet.java

j2me做的照相程序使用mmapi给有需要做这方面需要的人

/* License
 *
 * Copyright 1994-2004 Sun Microsystems, Inc. All Rights Reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *  * Redistribution of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 *
 *  * Redistribution in binary form must reproduce the above copyright notice,
 *      this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *
 * Neither the name of Sun Microsystems, Inc. or the names of contributors
 * may be used to endorse or promote products derived from this software
 * without specific prior written permission.
 *
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
 * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
 * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MICROSYSTEMS, INC. ("SUN")
 * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
 * AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
 * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
 * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL,
 * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY
 * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
 * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 *
 * You acknowledge that this software is not designed, licensed or intended
 * for use in the design, construction, operation or maintenance of any
 * nuclear facility.
 */

import java.io.IOException;

import javax.microedition.lcdui.*;
import javax.microedition.media.*;
import javax.microedition.media.control.*;
import javax.microedition.midlet.MIDlet;

public class SnapperMIDlet extends MIDlet implements CommandListener {
    private Display mDisplay;
    public int bytelen;
    private Form mMainForm;

    private Command mExitCommand, mCameraCommand;
    private Command mBackCommand, mCaptureCommand;

    private Player mPlayer;
    private VideoControl mVideoControl;

    public SnapperMIDlet() {
        mExitCommand = new Command("Exit", Command.EXIT, 0);
        mCameraCommand = new Command("Camera", Command.SCREEN, 0);
        mBackCommand = new Command("Back", Command.BACK, 0);
        mCaptureCommand = new Command("Capture", Command.SCREEN, 0);

        mMainForm = new Form("Snapper");
        mMainForm.addCommand(mExitCommand);
        String supports = System.getProperty("video.snapshot.encodings");
        if (supports != null && supports.length() > 0) {
            mMainForm.append("Ready to take pictures.");
            mMainForm.addCommand(mCameraCommand);
        } else {
            mMainForm.append("Snapper cannot use this " +
                             "device to take pictures.");
        }
        mMainForm.setCommandListener(this);
    }

    public void startApp() {
        mDisplay = Display.getDisplay(this);

        mDisplay.setCurrent(mMainForm);
    }

    public void pauseApp() {}

    public void destroyApp(boolean unconditional) {
    }

    public void commandAction(Command c, Displayable s) {
        if (c.getCommandType() == Command.EXIT) {
            destroyApp(true);
            notifyDestroyed();
        } else if (c == mCameraCommand) {
            showCamera();
        } else if (c == mBackCommand) {
            mDisplay.setCurrent(mMainForm);
        } else if (c == mCaptureCommand) {
            capture();
        }
    }

    private void showCamera() {
        try {
            mPlayer = Manager.createPlayer("capture://video");
            mPlayer.realize();

            mVideoControl = (VideoControl) mPlayer.getControl("VideoControl");

            Canvas canvas = new CameraCanvas(this, mVideoControl);
            canvas.addCommand(mBackCommand);
            canvas.addCommand(mCaptureCommand);
            canvas.setCommandListener(this);
            mDisplay.setCurrent(canvas);

            /*
                   Form form = new Form("Camera form");
                   Item item = (Item)mVideoControl.initDisplayMode(
                GUIControl.USE_GUI_PRIMITIVE, null);
                   form.append(item);
                   form.addCommand(mBackCommand);
                   form.addCommand(mCaptureCommand);
                   form.setCommandListener(this);
                   mDisplay.setCurrent(form);
             */

            mPlayer.start();
        } catch (IOException ioe) {
            handleException(ioe);
        } catch (MediaException me) {
            handleException(me);
        }
    }

    public void capture() {
        try {
            // Get the image.
            byte[] raw = mVideoControl.getSnapshot(null);
//                    "encoding=png&width=320&height=240");
            bytelen = raw.length;
            Image image = Image.createImage(raw, 0, raw.length);

            Image thumb = createThumbnail(image);

            // Place it in the main form.
            if (mMainForm.size() > 0 && mMainForm.get(0) instanceof StringItem) {
                mMainForm.delete(0);
            }
            mMainForm.append(thumb);

            // Flip back to the main form.
            mDisplay.setCurrent(mMainForm);

            // Shut down the player.
            mPlayer.close();
            mPlayer = null;
            mVideoControl = null;
        } catch (MediaException me) {
            handleException(me);
        }
    }

    private void handleException(Exception e) {
        Alert a = new Alert("Exception", e.toString(), null, null);
        a.setTimeout(Alert.FOREVER);
        mDisplay.setCurrent(a, mMainForm);
    }

    private Image createThumbnail(Image image) {
        int sourceWidth = image.getWidth();
        int sourceHeight = image.getHeight();

        int thumbWidth = 64;
        int thumbHeight = -1;

        if (thumbHeight == -1) {
            thumbHeight = thumbWidth * sourceHeight / sourceWidth;
        }

        Image thumb = Image.createImage(thumbWidth, thumbHeight);
        Graphics g = thumb.getGraphics();

        for (int y = 0; y < thumbHeight; y++) {
            for (int x = 0; x < thumbWidth; x++) {
                g.setClip(x, y, 1, 1);
                int dx = x * sourceWidth / thumbWidth;
                int dy = y * sourceHeight / thumbHeight;
                g.drawImage(image, x - dx, y - dy, Graphics.LEFT | Graphics.TOP);
            }
        }
        Image immutableThumb = Image.createImage(thumb);
        return immutableThumb;
    }
}