/*
* Copyright (C) 2009 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 android.media;
import java.io.FileDescriptor;
import java.io.IOException;
import java.io.OutputStream;
import android.content.ContentResolver;
import android.content.ContentUris;
import android.content.ContentValues;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.Rect;
import android.net.Uri;
import android.os.ParcelFileDescriptor;
import android.provider.BaseColumns;
import android.provider.MediaStore.Images;
import android.provider.MediaStore.Images.Thumbnails;
import android.util.Log;
/**
* Thumbnail generation routines for media provider. This class should only be used internaly.
* {@hide} THIS IS NOT FOR PUBLIC API.
*/
public class ThumbnailUtil {
private static final String TAG = "ThumbnailUtil";
//Whether we should recycle the input (unless the output is the input).
public static final boolean RECYCLE_INPUT = true;
public static final boolean NO_RECYCLE_INPUT = false;
public static final boolean ROTATE_AS_NEEDED = true;
public static final boolean NO_ROTATE = false;
public static final boolean USE_NATIVE = true;
public static final boolean NO_NATIVE = false;
public static final int THUMBNAIL_TARGET_SIZE = 320;
public static final int MINI_THUMB_TARGET_SIZE = 96;
public static final int THUMBNAIL_MAX_NUM_PIXELS = 512 * 384;
public static final int MINI_THUMB_MAX_NUM_PIXELS = 128 * 128;
public static final int UNCONSTRAINED = -1;
// Returns Options that set the native alloc flag for Bitmap decode.
public static BitmapFactory.Options createNativeAllocOptions() {
final BitmapFactory.Options options = new BitmapFactory.Options();
//options.inNativeAlloc = true;
return options;
}
/**
* Make a bitmap from a given Uri.
*
* @param uri
*/
public static Bitmap makeBitmap(int minSideLength, int maxNumOfPixels,
Uri uri, ContentResolver cr) {
return makeBitmap(minSideLength, maxNumOfPixels, uri, cr,
NO_NATIVE);
}
/*
* Compute the sample size as a function of minSideLength
* and maxNumOfPixels.
* minSideLength is used to specify that minimal width or height of a
* bitmap.
* maxNumOfPixels is used to specify the maximal size in pixels that is
* tolerable in terms of memory usage.
*
* The function returns a sample size based on the constraints.
* Both size and minSideLength can be passed in as IImage.UNCONSTRAINED,
* which indicates no care of the corresponding constraint.
* The functions prefers returning a sample size that
* generates a smaller bitmap, unless minSideLength = IImage.UNCONSTRAINED.
*
* Also, the function rounds up the sample size to a power of 2 or multiple
* of 8 because BitmapFactory only honors sample size this way.
* For example, BitmapFactory downsamples an image by 2 even though the
* request is 3. So we round up the sample size to avoid OOM.
*/
public static int computeSampleSize(BitmapFactory.Options options,
int minSideLength, int maxNumOfPixels) {
final int initialSize = computeInitialSampleSize(options, minSideLength,
maxNumOfPixels);
int roundedSize;
if (initialSize <= 8 ) {
roundedSize = 1;
while (roundedSize < initialSize) {
roundedSize <<= 1;
}
} else {
roundedSize = (initialSize + 7) / 8 * 8;
}
return roundedSize;
}
private static int computeInitialSampleSize(BitmapFactory.Options options,
int minSideLength, int maxNumOfPixels) {
final double w = options.outWidth;
final double h = options.outHeight;
final int lowerBound = (maxNumOfPixels == UNCONSTRAINED) ? 1 :
(int) Math.ceil(Math.sqrt(w * h / maxNumOfPixels));
final int upperBound = (minSideLength == UNCONSTRAINED) ? 128 :
(int) Math.min(Math.floor(w / minSideLength),
Math.floor(h / minSideLength));
if (upperBound < lowerBound) {
// return the larger one when there is no overlapping zone.
return lowerBound;
}
if ((maxNumOfPixels == UNCONSTRAINED) &&
(minSideLength == UNCONSTRAINED)) {
return 1;
} else if (minSideLength == UNCONSTRAINED) {
return lowerBound;
} else {
return upperBound;
}
}
public static Bitmap makeBitmap(int minSideLength, int maxNumOfPixels,
Uri uri, ContentResolver cr, boolean useNative) {
ParcelFileDescriptor input = null;
try {
input = cr.openFileDescriptor(uri, "r");
BitmapFactory.Options options = null;
if (useNative) {
options = createNativeAllocOptions();
}
return makeBitmap(minSideLength, maxNumOfPixels, uri, cr, input,
options);
} catch (final IOException ex) {
Log.e(TAG, "", ex);
return null;
} finally {
closeSilently(input);
}
}
// Rotates the bitmap by the specified degree.
// If a new bitmap is created, the original bitmap is recycled.
public static Bitmap rotate(Bitmap b, int degrees) {
if (degrees != 0 && b != null) {
final Matrix m = new Matrix();
m.setRotate(degrees,
(float) b.getWidth() / 2, (float) b.getHeight() / 2);
try {
final Bitmap b2 = Bitmap.createBitmap(
b, 0, 0, b.getWidth(), b.getHeight(), m, true);
if (b != b2) {
b.recycle();
b = b2;
}
} catch (final OutOfMemoryError ex) {
// We have no memory to rotate. Return the original bitmap.
}
}
return b;
}
private static void closeSilently(ParcelFileDescriptor c) {
if (c == null) {
return;
}
try {
c.close();
} catch (final Throwable t) {
// do nothing
}
}
private static ParcelFileDescriptor makeInputStream(
Uri uri, ContentResolver cr) {
try {
return cr.openFileDescriptor(uri, "r");
} catch (final IOException ex) {
return null;
}
}
public static Bitmap makeBitmap(int minSideLength, int maxNumOfPixels,
Uri uri, ContentResolver cr, ParcelFileDescriptor pfd,
BitmapFactory.Options options) {
Bitmap b = null;
try {
if (pfd == null) {
pfd = makeInputStream(uri, cr);
}
if (pfd == null) {
return null;
}
if (options == null) {
options = new BitmapFactory.Options();
}
final FileDescriptor fd = pfd.getFileDescriptor();
options.inSampleSize = 1;
options.inJustDecodeBounds = true;
BitmapFactory.decodeFileDescriptor(fd, null, options);
if (options.mCancel || options.outWidth == -1
|| options.outHeight == -1) {
return null;
}
options.inSampleSize = computeSampleSize(
options, minSideLength, maxNumOfPixels);
options.inJustDecodeBounds = false;
options.inDither = false;
options.inPreferredConfig = Bitmap.Config.ARGB_8888;
b = BitmapFactory.decodeFileDescriptor(fd, null, options);
} catch (final OutOfMemoryError ex) {
Log.e(TAG, "Got oom exception ", ex);
return null;
} finally {
closeSilently(pfd);
}
return b;
}
/**
* Creates a centered bitmap of the desired size.
* @param source
* @param recycle whether we want to recycle the input
*/
public static Bitmap extractMiniThumb(
Bitmap source, int width, int height, boolean recycle) {
if (source == null) {
return null;
}
float scale;
if (source.getWidth() < source.getHeight()) {
scale = width / (float) source.getWidth();
} else {
scale = height / (float) source.getHeight();
}
final Matrix matrix = new Matrix();
matrix.setScale(scale, scale);
final Bitmap miniThumbnail = transform(matrix, source, width, height, true, recycle);
return miniThumbnail;
}
/**
* Create a video thumbnail for a video. May return null if the video is
* corrupt.
*
* @param filePath
*/
public static Bitmap createVideoThumbnail(String filePath) {
Bitmap bitmap = null;
final MediaMetadataRetriever retriever = new MediaMetadataRetriever();
try {
retriever.setMode(MediaMetadataRetriever.MODE_CAPTURE_FRAME_ONLY);
retriever.setDataSource(filePath);
bitmap = retriever.captureFrame();
} catch (final IllegalArgumentException ex) {
// Assume this is a corrupt video file
} catch (final RuntimeException ex) {
// Assume this is a corrupt video file.
} finally {
try {
retriever.release();
} catch (final RuntimeException ex) {
// Ignore failures while cleaning up.
}
}
return bitmap;
}
/**
* This method first examines if the thumbnail embedded in EXIF is bigger than our target
* size. If not, then it'll create a thumbnail from original image. Due to efficiency
* consideration, we want to let MediaThumbRequest avoid calling this method twice for
* both kinds, so it only requests for MICRO_KIND and set saveImage to true.
*
* This method always returns a "square thumbnail" for MICRO_KIND thumbnail.
*
* @param cr ContentResolver
* @param filePath file path needed by EXIF interface
* @param uri URI of original image
* @param origId image id
* @param kind either MINI_KIND or MICRO_KIND
* @param saveImage Whether to save MINI_KIND thumbnail obtained in this method.
* @return Bitmap
*/
public static Bitmap createImageThumbnail(ContentResolver cr, String filePath, Uri uri,
long origId, int kind, boolean saveMini) {
final boolean wantMini = (kind == Images.Thumbnails.MINI_KIND || saveMini);
final int targetSize = wantMini ?
ThumbnailUtil.THUMBNAIL_TARGET_SIZE : ThumbnailUtil.MINI_THUMB_TARGET_SIZE;
final int maxPixels = wantMini ?
ThumbnailUtil.THUMBNAIL_MAX_NUM_PIXELS : ThumbnailUtil.MINI_THUMB_MAX_NUM_PIXELS;
final byte[] thumbData = createThumbnailFromEXIF(filePath, targetSize);
Bitmap bitmap = null;
if (thumbData != null) {
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inSampleSize = computeSampleSize(options, targetSize, maxPixels);
options.inDither = false;
options.inPreferredConfig = Bitmap.Config.ARGB_8888;
options.inJustDecodeBounds = false;
bitmap = BitmapFactory.decodeByteArray(thumbData, 0, thumbData.length, options);
}
if (bitmap == null) {
bitmap = ThumbnailUtil.makeBitmap(targetSize, maxPixels, uri, cr);
}
if (bitmap == null) {
return null;
}
if (saveMini) {
if (thumbData != null) {
ThumbnailUtil.storeThumbnail(cr, origId, thumbData, bitmap.getWidth(),
bitmap.getHeight());
} else {
ThumbnailUtil.storeThumbnail(cr, origId, bitmap);
}
}
if (kind == Images.Thumbnails.MICRO_KIND) {
// now we make it a "square thumbnail" for MICRO_KIND thumbnail
bitmap = ThumbnailUtil.extractMiniThumb(bitmap,
ThumbnailUtil.MINI_THUMB_TARGET_SIZE,
ThumbnailUtil.MINI_THUMB_TARGET_SIZE, ThumbnailUtil.RECYCLE_INPUT);
}
return bitmap;
}
public static Bitmap transform(Matrix scaler,
Bitmap source,
int targetWidth,
int targetHeight,
boolean scaleUp,
boolean recycle) {
final int deltaX = source.getWidth() - targetWidth;
final int deltaY = source.getHeight() - targetHeight;
if (!scaleUp && (deltaX < 0 || deltaY < 0)) {
/*
* In this case the bitmap is smaller, at least in one dimension,
* than the target. Transform it by placing as much of the image
* as possible into the target and leaving the top/bottom or
* left/right (or both) black.
*/
final Bitmap b2 = Bitmap.createBitmap(targetWidth, targetHeight,
Bitmap.Config.ARGB_8888);
final Canvas c = new Canvas(b2);
final int deltaXHalf = Math.max(0, deltaX / 2);
final int deltaYHalf = Math.max(0, deltaY / 2);
final Rect src = new Rect(
deltaXHalf,
deltaYHalf,
deltaXHalf + Math.min(targetWidth, source.getWidth()),
deltaYHalf + Math.min(targetHeight, source.getHeight()));
final int dstX = (targetWidth - src.width()) / 2;
final int dstY = (targetHeight - src.height()) / 2;
final Rect dst = new Rect(
dstX,
dstY,
targetWidth - dstX,
targetHeight - dstY);
c.drawBitmap(source, src, dst, null);
if (recycle) {
source.recycle();
}
return b2;
}
final float bitmapWidthF = source.getWidth();
final float bitmapHeightF = source.getHeight();
final float bitmapAspect = bitmapWidthF / bitmapHeightF;
final float viewAspect = (float) targetWidth / targetHeight;
if (bitmapAspect > viewAspect) {
final float scale = targetHeight / bitmapHeightF;
if (scale < .9F || scale > 1F) {
scaler.setScale(scale, scale);
} else {
scaler = null;
}
} else {
final float scale = targetWidth / bitmapWidthF;
if (scale < .9F || scale > 1F) {
scaler.setScale(scale, scale);
} else {
scaler = null;
}
}
Bitmap b1;
if (scaler != null) {
// this is used for minithumb and crop, so we want to filter here.
b1 = Bitmap.createBitmap(source, 0, 0,
source.getWidth(), source.getHeight(), scaler, true);
} else {
b1 = source;
}
if (recycle && b1 != source) {
source.recycle();
}
final int dx1 = Math.max(0, b1.getWidth() - targetWidth);
final int dy1 = Math.max(0, b1.getHeight() - targetHeight);
final Bitmap b2 = Bitmap.createBitmap(
b1,
dx1 / 2,
dy1 / 2,
targetWidth,
targetHeight);
if (b2 != b1) {
if (recycle || b1 != source) {
b1.recycle();
}
}
return b2;
}
private static final String[] THUMB_PROJECTION = new String[] {
BaseColumns._ID // 0
};
/**
* Look up thumbnail uri by given imageId, it will be automatically created if it's not created
* yet. Most of the time imageId is identical to thumbId, but it's not always true.
* @param req
* @param width
* @param height
* @return Uri Thumbnail uri
*/
private static Uri getImageThumbnailUri(ContentResolver cr, long origId, int width, int height) {
final Uri thumbUri = Images.Thumbnails.EXTERNAL_CONTENT_URI;
final Cursor c = cr.query(thumbUri, THUMB_PROJECTION,
Thumbnails.IMAGE_ID + "=?",
new String[]{String.valueOf(origId)}, null);
try {
if (c.moveToNext()) {
return ContentUris.withAppendedId(thumbUri, c.getLong(0));
}
} finally {
if (c != null) {
c.close();
}
}
final ContentValues values = new ContentValues(4);
values.put(Thumbnails.KIND, Thumbnails.MINI_KIND);
values.put(Thumbnails.IMAGE_ID, origId);
values.put(Thumbnails.HEIGHT, height);
values.put(Thumbnails.WIDTH, width);
try {
return cr.insert(thumbUri, values);
} catch (final Exception ex) {
Log.w(TAG, ex);
return null;
}
}
/**
* Store a given thumbnail in the database. (Bitmap)
*/
private static boolean storeThumbnail(ContentResolver cr, long origId, Bitmap thumb) {
if (thumb == null) {
return false;
}
try {
final Uri uri = getImageThumbnailUri(cr, origId, thumb.getWidth(), thumb.getHeight());
final OutputStream thumbOut = cr.openOutputStream(uri);
thumb.compress(Bitmap.CompressFormat.JPEG, 85, thumbOut);
thumbOut.close();
return true;
} catch (final Throwable t) {
Log.e(TAG, "Unable to store thumbnail", t);
return false;
}
}
/**
* Store a given thumbnail in the database. (byte array)
*/
private static boolean storeThumbnail(ContentResolver cr, long origId, byte[] jpegThumbnail,
int width, int height) {
if (jpegThumbnail == null) {
return false;
}
final Uri uri = getImageThumbnailUri(cr, origId, width, height);
if (uri == null) {
return false;
}
try {
final OutputStream thumbOut = cr.openOutputStream(uri);
thumbOut.write(jpegThumbnail);
thumbOut.close();
return true;
} catch (final Throwable t) {
Log.e(TAG, "Unable to store thumbnail", t);
return false;
}
}
// Extract thumbnail in image that meets the targetSize criteria.
static byte[] createThumbnailFromEXIF(String filePath, int targetSize) {
if (filePath == null) {
return null;
}
try {
final ExifInterface exif = new ExifInterface(filePath);
if (exif == null) {
return null;
}
final byte [] thumbData = exif.getThumbnail();
if (thumbData == null) {
return null;
}
// Sniff the size of the EXIF thumbnail before decoding it. Photos
// from the device will pass, but images that are side loaded from
// other cameras may not.
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeByteArray(thumbData, 0, thumbData.length, options);
final int width = options.outWidth;
final int height = options.outHeight;
if (width >= targetSize && height >= targetSize) {
return thumbData;
}
} catch (final IOException ex) {
Log.w(TAG, ex);
}
return null;
}
}