src/com/android/videoeditor/widgets/AudioTrackView.java - platform/packages/apps/VideoEditor - Git at Google

 /*
  * Copyright (C) 2010 The Android Open Source Project
  *
  * 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.
  */

 package com.android.videoeditor.widgets;

 import android.content.Context;
 import android.content.res.Resources;
 import android.graphics.Canvas;
 import android.graphics.Paint;
 import android.graphics.Rect;
 import android.media.videoeditor.WaveformData;
 import android.util.AttributeSet;
 import android.util.DisplayMetrics;
 import android.view.Display;
 import android.view.GestureDetector;
 import android.view.MotionEvent;
 import android.view.View;
 import android.view.WindowManager;

 import com.android.videoeditor.service.MovieAudioTrack;
 import com.android.videoeditor.R;

 /**
  * Audio track view
  */
 public class AudioTrackView extends View {
     // Instance variables
     private final GestureDetector mSimpleGestureDetector;
     private final Paint mLinePaint;
     private final Paint mLoopPaint;
     private final Rect mProgressDestRect;
     private final ScrollViewListener mScrollListener;

     private double[] mNormalizedGains;
     private long mTimelineDurationMs;
     private int mProgress;
     private ItemSimpleGestureListener mGestureListener;
     private WaveformData mWaveformData;
     private int mScrollX;
     private int mScreenWidth;

     /*
      * {@inheritDoc}
      */
     public AudioTrackView(Context context, AttributeSet attrs, int defStyle) {
         super(context, attrs, defStyle);

         final Resources resources = getResources();

         // Use this Paint for drawing the audio samples
         mLinePaint = new Paint();
         mLinePaint.setAntiAlias(false);
         mLinePaint.setStrokeWidth(1);
         mLinePaint.setColor(resources.getColor(R.color.audio_waveform));

         // Use this Paint to draw the loop separator
         mLoopPaint = new Paint();
         mLoopPaint.setAntiAlias(false);
         mLoopPaint.setStrokeWidth(1);
         mLoopPaint.setColor(resources.getColor(R.color.audio_loop_separator));

         // Prepare the bitmap rectangles
         final ProgressBar progressBar = ProgressBar.getProgressBar(context);
         final int layoutHeight = (int)resources.getDimension(R.dimen.audio_layout_height);
         mProgressDestRect = new Rect(getPaddingLeft(),
                 layoutHeight - progressBar.getHeight() - getPaddingBottom(), 0,
                 layoutHeight - getPaddingBottom());

         // Setup the gesture listener
         mSimpleGestureDetector = new GestureDetector(context,
                 new GestureDetector.SimpleOnGestureListener() {
                     /*
                      * {@inheritDoc}
                      */
                     @Override
                     public boolean onSingleTapConfirmed(MotionEvent e) {
                         if (mGestureListener != null) {
                             return mGestureListener.onSingleTapConfirmed(AudioTrackView.this, -1,
                                     e);
                         } else {
                             return false;
                         }
                     }

                     /*
                      * {@inheritDoc}
                      */
                     @Override
                     public void onLongPress (MotionEvent e) {
                         if (mGestureListener != null) {
                             mGestureListener.onLongPress(AudioTrackView.this, e);
                         }
                     }
                 });

         mScrollListener = new ScrollViewListener() {
             @Override
             public void onScrollBegin(View view, int scrollX, int scrollY, boolean appScroll) {
             }

             @Override
             public void onScrollProgress(View view, int scrollX, int scrollY, boolean appScroll) {
             }

             @Override
             public void onScrollEnd(View view, int scrollX, int scrollY, boolean appScroll) {
                 mScrollX = scrollX;
                 invalidate();
             }
         };

         // Get the screen width
         final Display display = ((WindowManager)context.getSystemService(
                 Context.WINDOW_SERVICE)).getDefaultDisplay();
         final DisplayMetrics metrics = new DisplayMetrics();
         display.getMetrics(metrics);
         mScreenWidth = metrics.widthPixels;

         mProgress = -1;
     }

     public AudioTrackView(Context context, AttributeSet attrs) {
         this(context, attrs, 0);
     }

     public AudioTrackView(Context context) {
         this(context, null, 0);
     }

     @Override
     protected void onAttachedToWindow() {
         final TimelineHorizontalScrollView scrollView =
             (TimelineHorizontalScrollView)((View)((View)getParent()).getParent()).getParent();
         mScrollX = scrollView.getScrollX();
         scrollView.addScrollListener(mScrollListener);
     }

     @Override
     protected void onDetachedFromWindow() {
         final TimelineHorizontalScrollView scrollView =
             (TimelineHorizontalScrollView)((View)((View)getParent()).getParent()).getParent();
         scrollView.removeScrollListener(mScrollListener);
     }

     /**
      * @param listener The gesture listener
      */
     public void setGestureListener(ItemSimpleGestureListener listener) {
         mGestureListener = listener;
     }

     /**
      * Set the waveform data
      *
      * @param waveformData The waveform data
      */
     public void setWaveformData(WaveformData waveformData) {
         mWaveformData = waveformData;
         final int numFrames = mWaveformData.getFramesCount();
         final short[] frameGains = mWaveformData.getFrameGains();
         final double[] smoothedGains = new double[numFrames];

         if (numFrames == 1) {
             smoothedGains[0] = frameGains[0];
         } else if (numFrames == 2) {
             smoothedGains[0] = frameGains[0];
             smoothedGains[1] = frameGains[1];
         } else if (numFrames > 2) {
             smoothedGains[0] = (frameGains[0] / 2.0) + (frameGains[1] / 2.0);
             for (int i = 1; i < numFrames - 1; i++) {
                 smoothedGains[i] =
                     (frameGains[i - 1] / 3.0) + (frameGains[i] / 3.0) + (frameGains[i + 1] / 3.0);
             }
             smoothedGains[numFrames - 1] = (frameGains[numFrames - 2] / 2.0) +
                 (frameGains[numFrames - 1] / 2.0);
         }

         // Make sure the range is no more than 0 - 255
         double maxGain = 1.0;
         for (int i = 0; i < numFrames; i++) {
             if (smoothedGains[i] > maxGain) {
                 maxGain = smoothedGains[i];
             }
         }

         double scaleFactor = 1.0;
         if (maxGain > 255.0) {
             scaleFactor = 255 / maxGain;
         }

         // Build histogram of 256 bins and figure out the new scaled max
         maxGain = 0;
         final int gainHist[] = new int[256];
         for (int i = 0; i < numFrames; i++) {
             int smoothedGain = (int)(smoothedGains[i] * scaleFactor);
             if (smoothedGain < 0) {
                 smoothedGain = 0;
             }
             if (smoothedGain > 255) {
                 smoothedGain = 255;
             }

             if (smoothedGain > maxGain) {
                 maxGain = smoothedGain;
             }

             gainHist[smoothedGain]++;
         }

         // Re-calibrate the minimum to be 5%
         double minGain = 0;
         int sum = 0;
         while (minGain < 255 && sum < numFrames / 20) {
             sum += gainHist[(int)minGain];
             minGain++;
         }

         // Re-calibrate the max to be 99%
         sum = 0;
         while (maxGain > 2 && sum < numFrames / 100) {
             sum += gainHist[(int)maxGain];
             maxGain--;
         }

         // Compute the normalized heights
         final int halfHeight =
             (int)((getResources().getDimension(R.dimen.audio_layout_height) - getPaddingTop() -
                     getPaddingBottom() - 4) / 2);
         final MovieAudioTrack audioTrack = (MovieAudioTrack)getTag();

         final int numFramesComp = (int)audioTrack.getDuration() / mWaveformData.getFrameDuration();
         mNormalizedGains = new double[Math.max(numFramesComp, numFrames)];
         final double range = maxGain - minGain;
         for (int i = 0; i < numFrames; i++) {
             double value = (smoothedGains[i] * scaleFactor - minGain) / range;
             if (value < 0.0) {
                 value = 0.0;
             }

             if (value > 1.0) {
                 value = 1.0;
             }

             mNormalizedGains[i] = value * value * halfHeight;
         }
     }

     /**
      * The project duration has changed
      *
      * @param timelineDurationMs The new timeline duration
      */
     public void updateTimelineDuration(long timelineDurationMs) {
         mTimelineDurationMs = timelineDurationMs;
     }

     /**
      * The audio track processing progress
      *
      * @param progress The progress
      */
     public void setProgress(int progress) {
         mProgress = progress;

         invalidate();
     }

     /**
      * @return The waveform data
      */
     public WaveformData getWaveformData() {
         return mWaveformData;
     }

     @Override
     protected void onDraw(Canvas canvas) {
         super.onDraw(canvas);

         if (mWaveformData == null) {
             if (mProgress >= 0) {
                 ProgressBar.getProgressBar(getContext()).draw(canvas, mProgress,
                         mProgressDestRect, getPaddingLeft(), getWidth() - getPaddingRight());
             }
         } else if (mTimelineDurationMs > 0) { // Draw waveform
             // Compute the number of frames in the trimmed audio track
             final MovieAudioTrack audioTrack = (MovieAudioTrack)getTag();
             final int startFrame = (int)(audioTrack.getBoundaryBeginTime() /
                     mWaveformData.getFrameDuration());
             final int numFrames =
                 (int)(audioTrack.getTimelineDuration() / mWaveformData.getFrameDuration());

             final int ctr = getHeight() / 2;
             short value;
             int index;
             final int start = Math.max(mScrollX - mScreenWidth / 2, getPaddingLeft());
             final int limit = Math.min(mScrollX + mScreenWidth, getWidth() - getPaddingRight());
             if (audioTrack.isAppLooping()) {
                 // Compute the milliseconds / pixel at the current zoom level
                 final float framesPerPixel = mTimelineDurationMs /
                     ((float)(mWaveformData.getFrameDuration() *
                             (((View)getParent()).getWidth() - mScreenWidth)));

                 for (int i = start; i < limit; i++) {
                     index = startFrame + (int)(framesPerPixel * i);
                     index = index % numFrames;
                     value = (short)mNormalizedGains[index];
                     canvas.drawLine(i, ctr - value, i, ctr + 1 + value, mLinePaint);

                     if (index == startFrame) { // Draw the loop delineation
                         canvas.drawLine(i, getPaddingTop(), i,
                                 getHeight() - getPaddingBottom(), mLinePaint);
                     }
                 }
             } else {
                 // Compute the milliseconds / pixel at the current zoom level
                 final float framesPerPixel =  audioTrack.getTimelineDuration() /
                     ((float)(mWaveformData.getFrameDuration() * getWidth()));

                 for (int i = start; i < limit; i++) {
                     index = startFrame + (int)(framesPerPixel * i);
                     value = (short)(mNormalizedGains[index]);
                     canvas.drawLine(i, ctr - value, i, ctr + 1 + value, mLinePaint);
                 }
             }
         }
     }

     @Override
     public boolean onTouchEvent(MotionEvent ev) {
         // Let the gesture detector inspect all events.
         mSimpleGestureDetector.onTouchEvent(ev);

         super.onTouchEvent(ev);
         return true;
     }
 }
	/*
	* Copyright (C) 2010 The Android Open Source Project
	*
	* 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.
	*/

	package com.android.videoeditor.widgets;

	import android.content.Context;
	import android.content.res.Resources;
	import android.graphics.Canvas;
	import android.graphics.Paint;
	import android.graphics.Rect;
	import android.media.videoeditor.WaveformData;
	import android.util.AttributeSet;
	import android.util.DisplayMetrics;
	import android.view.Display;
	import android.view.GestureDetector;
	import android.view.MotionEvent;
	import android.view.View;
	import android.view.WindowManager;

	import com.android.videoeditor.service.MovieAudioTrack;
	import com.android.videoeditor.R;

	/**
	* Audio track view
	*/
	public class AudioTrackView extends View {
	// Instance variables
	private final GestureDetector mSimpleGestureDetector;
	private final Paint mLinePaint;
	private final Paint mLoopPaint;
	private final Rect mProgressDestRect;
	private final ScrollViewListener mScrollListener;

	private double[] mNormalizedGains;
	private long mTimelineDurationMs;
	private int mProgress;
	private ItemSimpleGestureListener mGestureListener;
	private WaveformData mWaveformData;
	private int mScrollX;
	private int mScreenWidth;

	/*
	* {@inheritDoc}
	*/
	public AudioTrackView(Context context, AttributeSet attrs, int defStyle) {
	super(context, attrs, defStyle);

	final Resources resources = getResources();

	// Use this Paint for drawing the audio samples
	mLinePaint = new Paint();
	mLinePaint.setAntiAlias(false);
	mLinePaint.setStrokeWidth(1);
	mLinePaint.setColor(resources.getColor(R.color.audio_waveform));

	// Use this Paint to draw the loop separator
	mLoopPaint = new Paint();
	mLoopPaint.setAntiAlias(false);
	mLoopPaint.setStrokeWidth(1);
	mLoopPaint.setColor(resources.getColor(R.color.audio_loop_separator));

	// Prepare the bitmap rectangles
	final ProgressBar progressBar = ProgressBar.getProgressBar(context);
	final int layoutHeight = (int)resources.getDimension(R.dimen.audio_layout_height);
	mProgressDestRect = new Rect(getPaddingLeft(),
	layoutHeight - progressBar.getHeight() - getPaddingBottom(), 0,
	layoutHeight - getPaddingBottom());

	// Setup the gesture listener
	mSimpleGestureDetector = new GestureDetector(context,
	new GestureDetector.SimpleOnGestureListener() {
	/*
	* {@inheritDoc}
	*/
	@Override
	public boolean onSingleTapConfirmed(MotionEvent e) {
	if (mGestureListener != null) {
	return mGestureListener.onSingleTapConfirmed(AudioTrackView.this, -1,
	e);
	} else {
	return false;
	}
	}

	/*
	* {@inheritDoc}
	*/
	@Override
	public void onLongPress (MotionEvent e) {
	if (mGestureListener != null) {
	mGestureListener.onLongPress(AudioTrackView.this, e);
	}
	}
	});

	mScrollListener = new ScrollViewListener() {
	@Override
	public void onScrollBegin(View view, int scrollX, int scrollY, boolean appScroll) {
	}

	@Override
	public void onScrollProgress(View view, int scrollX, int scrollY, boolean appScroll) {
	}

	@Override
	public void onScrollEnd(View view, int scrollX, int scrollY, boolean appScroll) {
	mScrollX = scrollX;
	invalidate();
	}
	};

	// Get the screen width
	final Display display = ((WindowManager)context.getSystemService(
	Context.WINDOW_SERVICE)).getDefaultDisplay();
	final DisplayMetrics metrics = new DisplayMetrics();
	display.getMetrics(metrics);
	mScreenWidth = metrics.widthPixels;

	mProgress = -1;
	}

	public AudioTrackView(Context context, AttributeSet attrs) {
	this(context, attrs, 0);
	}

	public AudioTrackView(Context context) {
	this(context, null, 0);
	}

	@Override
	protected void onAttachedToWindow() {
	final TimelineHorizontalScrollView scrollView =
	(TimelineHorizontalScrollView)((View)((View)getParent()).getParent()).getParent();
	mScrollX = scrollView.getScrollX();
	scrollView.addScrollListener(mScrollListener);
	}

	@Override
	protected void onDetachedFromWindow() {
	final TimelineHorizontalScrollView scrollView =
	(TimelineHorizontalScrollView)((View)((View)getParent()).getParent()).getParent();
	scrollView.removeScrollListener(mScrollListener);
	}

	/**
	* @param listener The gesture listener
	*/
	public void setGestureListener(ItemSimpleGestureListener listener) {
	mGestureListener = listener;
	}

	/**
	* Set the waveform data
	*
	* @param waveformData The waveform data
	*/
	public void setWaveformData(WaveformData waveformData) {
	mWaveformData = waveformData;
	final int numFrames = mWaveformData.getFramesCount();
	final short[] frameGains = mWaveformData.getFrameGains();
	final double[] smoothedGains = new double[numFrames];

	if (numFrames == 1) {
	smoothedGains[0] = frameGains[0];
	} else if (numFrames == 2) {
	smoothedGains[0] = frameGains[0];
	smoothedGains[1] = frameGains[1];
	} else if (numFrames > 2) {
	smoothedGains[0] = (frameGains[0] / 2.0) + (frameGains[1] / 2.0);
	for (int i = 1; i < numFrames - 1; i++) {
	smoothedGains[i] =
	(frameGains[i - 1] / 3.0) + (frameGains[i] / 3.0) + (frameGains[i + 1] / 3.0);
	}
	smoothedGains[numFrames - 1] = (frameGains[numFrames - 2] / 2.0) +
	(frameGains[numFrames - 1] / 2.0);
	}

	// Make sure the range is no more than 0 - 255
	double maxGain = 1.0;
	for (int i = 0; i < numFrames; i++) {
	if (smoothedGains[i] > maxGain) {
	maxGain = smoothedGains[i];
	}
	}

	double scaleFactor = 1.0;
	if (maxGain > 255.0) {
	scaleFactor = 255 / maxGain;
	}

	// Build histogram of 256 bins and figure out the new scaled max
	maxGain = 0;
	final int gainHist[] = new int[256];
	for (int i = 0; i < numFrames; i++) {
	int smoothedGain = (int)(smoothedGains[i] * scaleFactor);
	if (smoothedGain < 0) {
	smoothedGain = 0;
	}
	if (smoothedGain > 255) {
	smoothedGain = 255;
	}

	if (smoothedGain > maxGain) {
	maxGain = smoothedGain;
	}

	gainHist[smoothedGain]++;
	}

	// Re-calibrate the minimum to be 5%
	double minGain = 0;
	int sum = 0;
	while (minGain < 255 && sum < numFrames / 20) {
	sum += gainHist[(int)minGain];
	minGain++;
	}

	// Re-calibrate the max to be 99%
	sum = 0;
	while (maxGain > 2 && sum < numFrames / 100) {
	sum += gainHist[(int)maxGain];
	maxGain--;
	}

	// Compute the normalized heights
	final int halfHeight =
	(int)((getResources().getDimension(R.dimen.audio_layout_height) - getPaddingTop() -
	getPaddingBottom() - 4) / 2);
	final MovieAudioTrack audioTrack = (MovieAudioTrack)getTag();

	final int numFramesComp = (int)audioTrack.getDuration() / mWaveformData.getFrameDuration();
	mNormalizedGains = new double[Math.max(numFramesComp, numFrames)];
	final double range = maxGain - minGain;
	for (int i = 0; i < numFrames; i++) {
	double value = (smoothedGains[i] * scaleFactor - minGain) / range;
	if (value < 0.0) {
	value = 0.0;
	}

	if (value > 1.0) {
	value = 1.0;
	}

	mNormalizedGains[i] = value * value * halfHeight;
	}
	}

	/**
	* The project duration has changed
	*
	* @param timelineDurationMs The new timeline duration
	*/
	public void updateTimelineDuration(long timelineDurationMs) {
	mTimelineDurationMs = timelineDurationMs;
	}

	/**
	* The audio track processing progress
	*
	* @param progress The progress
	*/
	public void setProgress(int progress) {
	mProgress = progress;

	invalidate();
	}

	/**
	* @return The waveform data
	*/
	public WaveformData getWaveformData() {
	return mWaveformData;
	}

	@Override
	protected void onDraw(Canvas canvas) {
	super.onDraw(canvas);

	if (mWaveformData == null) {
	if (mProgress >= 0) {
	ProgressBar.getProgressBar(getContext()).draw(canvas, mProgress,
	mProgressDestRect, getPaddingLeft(), getWidth() - getPaddingRight());
	}
	} else if (mTimelineDurationMs > 0) { // Draw waveform
	// Compute the number of frames in the trimmed audio track
	final MovieAudioTrack audioTrack = (MovieAudioTrack)getTag();
	final int startFrame = (int)(audioTrack.getBoundaryBeginTime() /
	mWaveformData.getFrameDuration());
	final int numFrames =
	(int)(audioTrack.getTimelineDuration() / mWaveformData.getFrameDuration());

	final int ctr = getHeight() / 2;
	short value;
	int index;
	final int start = Math.max(mScrollX - mScreenWidth / 2, getPaddingLeft());
	final int limit = Math.min(mScrollX + mScreenWidth, getWidth() - getPaddingRight());
	if (audioTrack.isAppLooping()) {
	// Compute the milliseconds / pixel at the current zoom level
	final float framesPerPixel = mTimelineDurationMs /
	((float)(mWaveformData.getFrameDuration() *
	(((View)getParent()).getWidth() - mScreenWidth)));

	for (int i = start; i < limit; i++) {
	index = startFrame + (int)(framesPerPixel * i);
	index = index % numFrames;
	value = (short)mNormalizedGains[index];
	canvas.drawLine(i, ctr - value, i, ctr + 1 + value, mLinePaint);

	if (index == startFrame) { // Draw the loop delineation
	canvas.drawLine(i, getPaddingTop(), i,
	getHeight() - getPaddingBottom(), mLinePaint);
	}
	}
	} else {
	// Compute the milliseconds / pixel at the current zoom level
	final float framesPerPixel = audioTrack.getTimelineDuration() /
	((float)(mWaveformData.getFrameDuration() * getWidth()));

	for (int i = start; i < limit; i++) {
	index = startFrame + (int)(framesPerPixel * i);
	value = (short)(mNormalizedGains[index]);
	canvas.drawLine(i, ctr - value, i, ctr + 1 + value, mLinePaint);
	}
	}
	}
	}

	@Override
	public boolean onTouchEvent(MotionEvent ev) {
	// Let the gesture detector inspect all events.
	mSimpleGestureDetector.onTouchEvent(ev);

	super.onTouchEvent(ev);
	return true;
	}
	}