Mega Code Archive
Make a direct NIO ByteBuffer from an array of bytes
<![CDATA[
//package edu.dhbw.andar.util;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import java.util.Iterator;
import java.util.List;
import android.hardware.Camera.Size;
public class GraphicsUtil {
//private final static double epsilon = 0.001;
//this epsilon being so large is intended, as often there will not be an adequate resolution with
//the correct aspect ratio available
//so we trade the correct aspect ratio for faster rendering
private final static double epsilon = 0.17;
/**
* Make a direct NIO FloatBuffer from an array of floats
* @param arr The array
* @return The newly created FloatBuffer
*/
public static FloatBuffer makeFloatBuffer(float[] arr) {
ByteBuffer bb = ByteBuffer.allocateDirect(arr.length*4);
bb.order(ByteOrder.nativeOrder());
FloatBuffer fb = bb.asFloatBuffer();
fb.put(arr);
fb.position(0);
return fb;
}
/**
* Make a direct NIO ByteBuffer from an array of floats
* @param arr The array
* @return The newly created FloatBuffer
*/
public static ByteBuffer makeByteBuffer(byte[] arr) {
ByteBuffer bb = ByteBuffer.allocateDirect(arr.length);
bb.order(ByteOrder.nativeOrder());
bb.put(arr);
bb.position(0);
return bb;
}
public static ByteBuffer makeByteBuffer(int size) {
ByteBuffer bb = ByteBuffer.allocateDirect(size);
bb.position(0);
return bb;
}
/**
* Get the optimal preview size for the given screen size.
* @param sizes
* @param screenWidth
* @param screenHeight
* @return
*/
public static Size getOptimalPreviewSize(List<Size> sizes, int screenWidth, int screenHeight) {
double aspectRatio = ((double)screenWidth)/screenHeight;
Size optimalSize = null;
for (Iterator<Size> iterator = sizes.iterator(); iterator.hasNext();) {
Size currSize = iterator.next();
double curAspectRatio = ((double)currSize.width)/currSize.height;
//do the aspect ratios equal?
if ( Math.abs( aspectRatio - curAspectRatio ) < epsilon ) {
//they do
if(optimalSize!=null) {
//is the current size smaller than the one before
if(optimalSize.height>currSize.height && optimalSize.width>currSize.width) {
optimalSize = currSize;
}
} else {
optimalSize = currSize;
}
}
}
if(optimalSize == null) {
//did not find a size with the correct aspect ratio.. let's choose the smallest instead
for (Iterator<Size> iterator = sizes.iterator(); iterator.hasNext();) {
Size currSize = iterator.next();
if(optimalSize!=null) {
//is the current size smaller than the one before
if(optimalSize.height>currSize.height && optimalSize.width>currSize.width) {
optimalSize = currSize;
} else {
optimalSize = currSize;
}
}else {
optimalSize = currSize;
}
}
}
return optimalSize;
}
public static boolean containsSize(List<Size> sizes, Size size) {
for (Iterator<Size> iterator = sizes.iterator(); iterator.hasNext();) {
Size currSize = iterator.next();
if(currSize.width == size.width && currSize.height == size.height) {
return true;
}
}
return false;
}
public static Size getSmallestSize(List<Size> sizes) {
Size optimalSize = null;
for (Iterator<Size> iterator = sizes.iterator(); iterator.hasNext();) {
Size currSize = iterator.next();
if(optimalSize == null) {
optimalSize = currSize;
} else if(optimalSize.height>currSize.height && optimalSize.width>currSize.width) {
optimalSize = currSize;
}
}
return optimalSize;
}
}
]]>