Add new thumbnail API.
This commit is contained in:
Ray Chen
401
media/java/android/media/ThumbnailUtil.java
Normal file
401
media/java/android/media/ThumbnailUtil.java
Normal file
@@ -0,0 +1,401 @@
|
||||
/*
|
||||
* 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 android.net.Uri;
|
||||
import android.os.ParcelFileDescriptor;
|
||||
import android.util.Log;
|
||||
|
||||
import android.content.ContentResolver;
|
||||
import android.graphics.Bitmap;
|
||||
import android.graphics.BitmapFactory;
|
||||
import android.graphics.Canvas;
|
||||
import android.graphics.Matrix;
|
||||
import android.graphics.Rect;
|
||||
import android.media.MediaMetadataRetriever;
|
||||
|
||||
import java.io.ByteArrayOutputStream;
|
||||
import java.io.FileDescriptor;
|
||||
import java.io.FileNotFoundException;
|
||||
import java.io.IOException;
|
||||
import java.io.OutputStream;
|
||||
|
||||
/**
|
||||
* 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() {
|
||||
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) {
|
||||
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) {
|
||||
double w = options.outWidth;
|
||||
double h = options.outHeight;
|
||||
|
||||
int lowerBound = (maxNumOfPixels == UNCONSTRAINED) ? 1 :
|
||||
(int) Math.ceil(Math.sqrt(w * h / maxNumOfPixels));
|
||||
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 (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) {
|
||||
Matrix m = new Matrix();
|
||||
m.setRotate(degrees,
|
||||
(float) b.getWidth() / 2, (float) b.getHeight() / 2);
|
||||
try {
|
||||
Bitmap b2 = Bitmap.createBitmap(
|
||||
b, 0, 0, b.getWidth(), b.getHeight(), m, true);
|
||||
if (b != b2) {
|
||||
b.recycle();
|
||||
b = b2;
|
||||
}
|
||||
} catch (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 (Throwable t) {
|
||||
// do nothing
|
||||
}
|
||||
}
|
||||
|
||||
private static ParcelFileDescriptor makeInputStream(
|
||||
Uri uri, ContentResolver cr) {
|
||||
try {
|
||||
return cr.openFileDescriptor(uri, "r");
|
||||
} catch (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();
|
||||
|
||||
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 (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();
|
||||
}
|
||||
Matrix matrix = new Matrix();
|
||||
matrix.setScale(scale, scale);
|
||||
Bitmap miniThumbnail = transform(matrix, source, width, height, false, recycle);
|
||||
return miniThumbnail;
|
||||
}
|
||||
|
||||
/**
|
||||
* Creates a byte[] for a given bitmap of the desired size. Recycles the
|
||||
* input bitmap.
|
||||
*/
|
||||
public static byte[] miniThumbData(Bitmap source) {
|
||||
if (source == null) return null;
|
||||
|
||||
Bitmap miniThumbnail = extractMiniThumb(
|
||||
source, MINI_THUMB_TARGET_SIZE,
|
||||
MINI_THUMB_TARGET_SIZE,
|
||||
RECYCLE_INPUT);
|
||||
|
||||
ByteArrayOutputStream miniOutStream = new ByteArrayOutputStream();
|
||||
miniThumbnail.compress(Bitmap.CompressFormat.JPEG, 75, miniOutStream);
|
||||
miniThumbnail.recycle();
|
||||
|
||||
try {
|
||||
miniOutStream.close();
|
||||
byte [] data = miniOutStream.toByteArray();
|
||||
return data;
|
||||
} catch (java.io.IOException ex) {
|
||||
Log.e(TAG, "got exception ex " + ex);
|
||||
}
|
||||
return null;
|
||||
}
|
||||
|
||||
/**
|
||||
* 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;
|
||||
MediaMetadataRetriever retriever = new MediaMetadataRetriever();
|
||||
try {
|
||||
retriever.setMode(MediaMetadataRetriever.MODE_CAPTURE_FRAME_ONLY);
|
||||
retriever.setDataSource(filePath);
|
||||
bitmap = retriever.captureFrame();
|
||||
} catch (IllegalArgumentException ex) {
|
||||
// Assume this is a corrupt video file
|
||||
} catch (RuntimeException ex) {
|
||||
// Assume this is a corrupt video file.
|
||||
} finally {
|
||||
try {
|
||||
retriever.release();
|
||||
} catch (RuntimeException ex) {
|
||||
// Ignore failures while cleaning up.
|
||||
}
|
||||
}
|
||||
return bitmap;
|
||||
}
|
||||
|
||||
public static Bitmap transform(Matrix scaler,
|
||||
Bitmap source,
|
||||
int targetWidth,
|
||||
int targetHeight,
|
||||
boolean scaleUp,
|
||||
boolean recycle) {
|
||||
|
||||
int deltaX = source.getWidth() - targetWidth;
|
||||
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.
|
||||
*/
|
||||
Bitmap b2 = Bitmap.createBitmap(targetWidth, targetHeight,
|
||||
Bitmap.Config.ARGB_8888);
|
||||
Canvas c = new Canvas(b2);
|
||||
|
||||
int deltaXHalf = Math.max(0, deltaX / 2);
|
||||
int deltaYHalf = Math.max(0, deltaY / 2);
|
||||
Rect src = new Rect(
|
||||
deltaXHalf,
|
||||
deltaYHalf,
|
||||
deltaXHalf + Math.min(targetWidth, source.getWidth()),
|
||||
deltaYHalf + Math.min(targetHeight, source.getHeight()));
|
||||
int dstX = (targetWidth - src.width()) / 2;
|
||||
int dstY = (targetHeight - src.height()) / 2;
|
||||
Rect dst = new Rect(
|
||||
dstX,
|
||||
dstY,
|
||||
targetWidth - dstX,
|
||||
targetHeight - dstY);
|
||||
c.drawBitmap(source, src, dst, null);
|
||||
if (recycle) {
|
||||
source.recycle();
|
||||
}
|
||||
return b2;
|
||||
}
|
||||
float bitmapWidthF = source.getWidth();
|
||||
float bitmapHeightF = source.getHeight();
|
||||
|
||||
float bitmapAspect = bitmapWidthF / bitmapHeightF;
|
||||
float viewAspect = (float) targetWidth / targetHeight;
|
||||
|
||||
if (bitmapAspect > viewAspect) {
|
||||
float scale = targetHeight / bitmapHeightF;
|
||||
if (scale < .9F || scale > 1F) {
|
||||
scaler.setScale(scale, scale);
|
||||
} else {
|
||||
scaler = null;
|
||||
}
|
||||
} else {
|
||||
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();
|
||||
}
|
||||
|
||||
int dx1 = Math.max(0, b1.getWidth() - targetWidth);
|
||||
int dy1 = Math.max(0, b1.getHeight() - targetHeight);
|
||||
|
||||
Bitmap b2 = Bitmap.createBitmap(
|
||||
b1,
|
||||
dx1 / 2,
|
||||
dy1 / 2,
|
||||
targetWidth,
|
||||
targetHeight);
|
||||
|
||||
if (b2 != b1) {
|
||||
if (recycle || b1 != source) {
|
||||
b1.recycle();
|
||||
}
|
||||
}
|
||||
|
||||
return b2;
|
||||
}
|
||||
|
||||
|
||||
|
||||
}
|
||||
Reference in New Issue
Block a user