/*
* Copyright (c) 2013, Psiphon Inc.
* All rights reserved.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
package ca.psiphon.ploggy;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import android.content.Context;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageView;
/**
* Helpers for pictures.
*
* - Scaled-down thumbnail display with caching.
* - Create size-bounded scaled-down copy of a bitmap file for sharing.
*/
public class Pictures {
private static final String LOG_TAG = "Pictures";
private static final int MAX_PICTURE_SIZE_IN_PIXELS = 2097152; // approx. 8MB in ARGB_8888
private static BitmapCache mThumbnailCache = new BitmapCache();
public static boolean loadThumbnailWithClickToShowPicture(Context context, File source, ImageView target) {
if (!loadThumbnail(context, source, target)) {
return false;
}
// On click ImageView, load activity with full picture
final Context finalContext = context;
final String finalFilePath = source.getAbsolutePath();
target.setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(finalContext, ActivityShowPicture.class);
Bundle bundle = new Bundle();
bundle.putString(ActivityShowPicture.FILE_PATH_BUNDLE_KEY, finalFilePath);
intent.putExtras(bundle);
finalContext.startActivity(intent);
}
});
return true;
}
public static boolean loadThumbnail(Context context, File source, ImageView target) {
try {
String key = source.getAbsolutePath();
Bitmap bitmap = mThumbnailCache.get(key);
if (bitmap == null) {
// TODO: get actual dimensions of ImageView. Note: target.getWidth()
// returns 0 when the views are not fully instantiated.
int width = (int)context.getResources().getDimension(R.dimen.picture_thumbnail_width);
int height = (int)context.getResources().getDimension(R.dimen.picture_thumbnail_height);
bitmap = loadScaledBitmap(source, width, height);
mThumbnailCache.set(key, bitmap);
}
target.setImageBitmap(bitmap);
return true;
} catch (Utils.ApplicationError e) {
target.setImageResource(R.drawable.ic_picture_load_error);
}
return false;
}
public static boolean loadPicture(File source, ImageView target) {
try {
target.setImageBitmap(loadScaledBitmap(source, MAX_PICTURE_SIZE_IN_PIXELS));
return true;
} catch (Utils.ApplicationError e) {
target.setImageResource(R.drawable.ic_picture_load_error);
return false;
}
}
public static void copyScaledBitmapWithoutMetadata(File source, File target) throws Utils.ApplicationError {
FileOutputStream outputStream = null;
try {
// Extracting a bitmap from the file omits EXIF and other metadata, regardless of
// origin file type (JPEG, PNG, etc.)
// TODO: implement this by streaming (or using BitmapRegionDecoder) to avoid loading the entire bitmap into memory
Bitmap bitmap = loadScaledBitmap(source, MAX_PICTURE_SIZE_IN_PIXELS);
outputStream = new FileOutputStream(target);
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, outputStream);
bitmap.recycle();
} catch (IOException e) {
throw new Utils.ApplicationError(LOG_TAG, e);
} finally {
if (outputStream != null) {
try {
outputStream.close();
} catch (IOException e) {
}
}
}
}
private static Bitmap loadScaledBitmap(File source, int targetWidth, int targetHeight)
throws Utils.ApplicationError {
BitmapFactory.Options options = new BitmapFactory.Options();
decodeBitmapBounds(source, options);
options.inSampleSize =
inSampleSizeForDimensions(options.outWidth, options.outHeight, targetWidth, targetHeight);
return decodeBitmap(source, options);
}
private static Bitmap loadScaledBitmap(File source, int maxSizeInPixels)
throws Utils.ApplicationError {
BitmapFactory.Options options = new BitmapFactory.Options();
decodeBitmapBounds(source, options);
options.inSampleSize =
inSampleSizeForMaximumSize(options.outWidth, options.outHeight, maxSizeInPixels);
return decodeBitmap(source, options);
}
private static void decodeBitmapBounds(File source, BitmapFactory.Options options) {
options.inJustDecodeBounds = true;
// TODO: returns null for inJustDecodeBounds... so how to check for error?
BitmapFactory.decodeFile(source.getAbsolutePath(), options);
options.inJustDecodeBounds = false;
}
private static Bitmap decodeBitmap(File source, BitmapFactory.Options options)
throws Utils.ApplicationError {
try {
Bitmap bitmap = BitmapFactory.decodeFile(source.getAbsolutePath(), options);
if (bitmap == null) {
throw new Utils.ApplicationError(LOG_TAG, "cannot decode image");
}
return bitmap;
} catch (OutOfMemoryError e) {
// Expected condition due to bitmap loading; friend will eventually retry download
throw new Utils.ApplicationError(LOG_TAG, "out of memory error");
}
}
private static int inSampleSizeForDimensions(int width, int height, int targetWidth, int targetHeight) {
// Scale the picture down so both width and height fit in target
// Scale should be power of 2: http://developer.android.com/reference/android/graphics/BitmapFactory.Options.html#inSampleSize
int inSampleSize = 1;
while (width > targetWidth || height > targetHeight) {
inSampleSize *= 2;
width /= 2;
height /= 2;
}
return inSampleSize;
}
private static int inSampleSizeForMaximumSize(int width, int height, int maxSizeInPixels) {
// Scale the picture down so that it's total size in pixels <= MAX_PICTURE_SIZE_IN_PIXELS
// Scale should be power of 2: http://developer.android.com/reference/android/graphics/BitmapFactory.Options.html#inSampleSize
int sourceSizeInPixels = width * height;
int inSampleSize = 1;
while (sourceSizeInPixels > maxSizeInPixels) {
inSampleSize *= 2;
sourceSizeInPixels /= (inSampleSize * 2);
}
return inSampleSize;
}
}