Commit e08d779b by wanglei

更新读取Assets文件方法

1 parent 00e7d0f7
......@@ -19,38 +19,69 @@ import java.nio.MappedByteBuffer;
import java.nio.channels.FileChannel;
public class Utils {
/**
* Memory-map the model file in Assets.
*/
public static MappedByteBuffer loadModelFile(AssetManager assets, String modelFilename)
throws IOException {
AssetFileDescriptor fileDescriptor = assets.openFd(modelFilename);
FileInputStream inputStream = new FileInputStream(fileDescriptor.getFileDescriptor());
FileChannel fileChannel = inputStream.getChannel();
long startOffset = fileDescriptor.getStartOffset();
long declaredLength = fileDescriptor.getDeclaredLength();
return fileChannel.map(FileChannel.MapMode.READ_ONLY, startOffset, declaredLength);
}
public static void softmax(final float[] vals) {
float max = Float.NEGATIVE_INFINITY;
for (final float val : vals) {
max = Math.max(max, val);
}
float sum = 0.0f;
for (int i = 0; i < vals.length; ++i) {
vals[i] = (float) Math.exp(vals[i] - max);
sum += vals[i];
}
for (int i = 0; i < vals.length; ++i) {
vals[i] = vals[i] / sum;
}
}
public static float expit(final float x) {
return (float) (1. / (1. + Math.exp(-x)));
}
private static final String TAG = "Utils";
/**
* Memory-map the model file in Assets.
*/
public static MappedByteBuffer loadModelFile(AssetManager assets, String filePath) throws IOException {
AssetFileDescriptor fileDescriptor = assets.openFd(filePath);
MappedByteBuffer result = null;
try {
FileInputStream inputStream = new FileInputStream(fileDescriptor.getFileDescriptor());
try {
FileChannel fileChannel = inputStream.getChannel();
long startOffset = fileDescriptor.getStartOffset();
long declaredLength = fileDescriptor.getDeclaredLength();
result = fileChannel.map(FileChannel.MapMode.READ_ONLY, startOffset, declaredLength);
} catch (Throwable e) {
try {
inputStream.close();
} catch (Throwable e1) {
e.addSuppressed(e1);
}
throw e;
} finally {
inputStream.close();
}
} catch (Throwable e) {
if (fileDescriptor != null) {
try {
fileDescriptor.close();
} catch (Throwable e1) {
e.addSuppressed(e1);
}
}
Log.e(TAG, "WL_DEBUG loadMappedFile e = " + e, e);
} finally {
if (fileDescriptor != null) {
fileDescriptor.close();
}
}
return result;
}
public static void softmax(final float[] vals) {
float max = Float.NEGATIVE_INFINITY;
for (final float val : vals) {
max = Math.max(max, val);
}
float sum = 0.0f;
for (int i = 0; i < vals.length; ++i) {
vals[i] = (float) Math.exp(vals[i] - max);
sum += vals[i];
}
for (int i = 0; i < vals.length; ++i) {
vals[i] = vals[i] / sum;
}
}
public static float expit(final float x) {
return (float) (1. / (1. + Math.exp(-x)));
}
// public static Bitmap scale(Context context, String filePath) {
// AssetManager assetManager = context.getAssets();
......@@ -69,117 +100,112 @@ public class Utils {
// return bitmap;
// }
public static Bitmap getBitmapFromAsset(Context context, String filePath) {
AssetManager assetManager = context.getAssets();
public static Bitmap getBitmapFromAsset(Context context, String filePath) {
AssetManager assetManager = context.getAssets();
InputStream istr;
Bitmap bitmap = null;
try {
istr = assetManager.open(filePath);
bitmap = BitmapFactory.decodeStream(istr);
InputStream istr;
Bitmap bitmap = null;
try {
istr = assetManager.open(filePath);
bitmap = BitmapFactory.decodeStream(istr);
// return bitmap.copy(Bitmap.Config.ARGB_8888,true);
} catch (IOException e) {
// handle exception
Log.e("getBitmapFromAsset", "getBitmapFromAsset: " + e.getMessage());
}
return bitmap;
}
/**
* Returns a transformation matrix from one reference frame into another.
* Handles cropping (if maintaining aspect ratio is desired) and rotation.
*
* @param srcWidth Width of source frame.
* @param srcHeight Height of source frame.
* @param dstWidth Width of destination frame.
* @param dstHeight Height of destination frame.
* @param applyRotation Amount of rotation to apply from one frame to another.
* Must be a multiple of 90.
* @param maintainAspectRatio If true, will ensure that scaling in x and y remains constant,
* cropping the image if necessary.
* @return The transformation fulfilling the desired requirements.
*/
public static Matrix getTransformationMatrix(
final int srcWidth,
final int srcHeight,
final int dstWidth,
final int dstHeight,
final int applyRotation,
final boolean maintainAspectRatio) {
final Matrix matrix = new Matrix();
if (applyRotation != 0) {
// Translate so center of image is at origin.
matrix.postTranslate(-srcWidth / 2.0f, -srcHeight / 2.0f);
// Rotate around origin.
matrix.postRotate(applyRotation);
}
// Account for the already applied rotation, if any, and then determine how
// much scaling is needed for each axis.
final boolean transpose = (Math.abs(applyRotation) + 90) % 180 == 0;
final int inWidth = transpose ? srcHeight : srcWidth;
final int inHeight = transpose ? srcWidth : srcHeight;
// Apply scaling if necessary.
if (inWidth != dstWidth || inHeight != dstHeight) {
final float scaleFactorX = dstWidth / (float) inWidth;
final float scaleFactorY = dstHeight / (float) inHeight;
if (maintainAspectRatio) {
// Scale by minimum factor so that dst is filled completely while
// maintaining the aspect ratio. Some image may fall off the edge.
final float scaleFactor = Math.max(scaleFactorX, scaleFactorY);
matrix.postScale(scaleFactor, scaleFactor);
} else {
// Scale exactly to fill dst from src.
matrix.postScale(scaleFactorX, scaleFactorY);
}
}
if (applyRotation != 0) {
// Translate back from origin centered reference to destination frame.
matrix.postTranslate(dstWidth / 2.0f, dstHeight / 2.0f);
}
return matrix;
}
public static Bitmap processBitmap(Bitmap source, int size){
int image_height = source.getHeight();
int image_width = source.getWidth();
Bitmap croppedBitmap = Bitmap.createBitmap(size, size, Bitmap.Config.ARGB_8888);
Matrix frameToCropTransformations = getTransformationMatrix(image_width,image_height,size,size,0,false);
Matrix cropToFrameTransformations = new Matrix();
frameToCropTransformations.invert(cropToFrameTransformations);
final Canvas canvas = new Canvas(croppedBitmap);
canvas.drawBitmap(source, frameToCropTransformations, null);
return croppedBitmap;
}
public static void writeToFile(String data, Context context) {
try {
String baseDir = Environment.getExternalStorageDirectory().getAbsolutePath();
String fileName = "myFile.txt";
File file = new File(baseDir + File.separator + fileName);
FileOutputStream stream = new FileOutputStream(file);
try {
stream.write(data.getBytes());
} finally {
stream.close();
}
} catch (IOException e) {
Log.e("Exception", "File write failed: " + e.toString());
}
}
} catch (IOException e) {
// handle exception
Log.e("getBitmapFromAsset", "getBitmapFromAsset: " + e.getMessage());
}
return bitmap;
}
/**
* Returns a transformation matrix from one reference frame into another.
* Handles cropping (if maintaining aspect ratio is desired) and rotation.
*
* @param srcWidth Width of source frame.
* @param srcHeight Height of source frame.
* @param dstWidth Width of destination frame.
* @param dstHeight Height of destination frame.
* @param applyRotation Amount of rotation to apply from one frame to
* another. Must be a multiple of 90.
* @param maintainAspectRatio If true, will ensure that scaling in x and y
* remains constant, cropping the image if necessary.
* @return The transformation fulfilling the desired requirements.
*/
public static Matrix getTransformationMatrix(final int srcWidth, final int srcHeight, final int dstWidth,
final int dstHeight, final int applyRotation, final boolean maintainAspectRatio) {
final Matrix matrix = new Matrix();
if (applyRotation != 0) {
// Translate so center of image is at origin.
matrix.postTranslate(-srcWidth / 2.0f, -srcHeight / 2.0f);
// Rotate around origin.
matrix.postRotate(applyRotation);
}
// Account for the already applied rotation, if any, and then determine how
// much scaling is needed for each axis.
final boolean transpose = (Math.abs(applyRotation) + 90) % 180 == 0;
final int inWidth = transpose ? srcHeight : srcWidth;
final int inHeight = transpose ? srcWidth : srcHeight;
// Apply scaling if necessary.
if (inWidth != dstWidth || inHeight != dstHeight) {
final float scaleFactorX = dstWidth / (float) inWidth;
final float scaleFactorY = dstHeight / (float) inHeight;
if (maintainAspectRatio) {
// Scale by minimum factor so that dst is filled completely while
// maintaining the aspect ratio. Some image may fall off the edge.
final float scaleFactor = Math.max(scaleFactorX, scaleFactorY);
matrix.postScale(scaleFactor, scaleFactor);
} else {
// Scale exactly to fill dst from src.
matrix.postScale(scaleFactorX, scaleFactorY);
}
}
if (applyRotation != 0) {
// Translate back from origin centered reference to destination frame.
matrix.postTranslate(dstWidth / 2.0f, dstHeight / 2.0f);
}
return matrix;
}
public static Bitmap processBitmap(Bitmap source, int size) {
int image_height = source.getHeight();
int image_width = source.getWidth();
Bitmap croppedBitmap = Bitmap.createBitmap(size, size, Bitmap.Config.ARGB_8888);
Matrix frameToCropTransformations = getTransformationMatrix(image_width, image_height, size, size, 0, false);
Matrix cropToFrameTransformations = new Matrix();
frameToCropTransformations.invert(cropToFrameTransformations);
final Canvas canvas = new Canvas(croppedBitmap);
canvas.drawBitmap(source, frameToCropTransformations, null);
return croppedBitmap;
}
public static void writeToFile(String data, Context context) {
try {
String baseDir = Environment.getExternalStorageDirectory().getAbsolutePath();
String fileName = "myFile.txt";
File file = new File(baseDir + File.separator + fileName);
FileOutputStream stream = new FileOutputStream(file);
try {
stream.write(data.getBytes());
} finally {
stream.close();
}
} catch (IOException e) {
Log.e("Exception", "File write failed: " + e.toString());
}
}
}
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