home-school-contact-app/文档/Android/app/src/main/java/com/example/nanchen/aiyaschoolpush/im/ImageResizer.java

292 lines
9.0 KiB
Java

package com.example.nanchen.aiyaschoolpush.im;
import android.annotation.TargetApi;
import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.media.ThumbnailUtils;
import android.os.Build;
import android.provider.MediaStore.Video.Thumbnails;
import java.io.FileDescriptor;
public class ImageResizer extends ImageWorker {
private static final String TAG = "ImageResizer";
protected int mImageWidth;
protected int mImageHeight;
/**
* Initialize providing a single target image size (used for both width and
* height);
*
* @param context
* @param imageWidth
* @param imageHeight
*/
public ImageResizer(Context context, int imageWidth, int imageHeight) {
super(context);
setImageSize(imageWidth, imageHeight);
}
/**
* Initialize providing a single target image size (used for both width and
* height);
*
* @param context
* @param imageSize
*/
public ImageResizer(Context context, int imageSize) {
super(context);
setImageSize(imageSize);
}
/**
* Set the target image width and height.
*
* @param width
* @param height
*/
public void setImageSize(int width, int height) {
mImageWidth = width;
mImageHeight = height;
}
/**
* Set the target image size (width and height will be the same).
*
* @param size
*/
public void setImageSize(int size) {
setImageSize(size, size);
}
/**
* The main processing method. This happens in a background task. In this
* case we are just sampling down the bitmap and returning it from a
* resource.
*
* @param resId
* @return
*/
private Bitmap processBitmap(int resId) {
// if (BuildConfig.DEBUG) {
// Log.d(TAG, "processBitmap - " + resId);
// }
return decodeSampledBitmapFromResource(mResources, resId, mImageWidth,
mImageHeight, getImageCache());
}
@Override
protected Bitmap processBitmap(Object data) {
String filePath=String.valueOf(data);
return ThumbnailUtils.createVideoThumbnail(filePath, Thumbnails.MICRO_KIND);
}
/**
* Decode and sample down a bitmap from resources to the requested width and
* height.
*
* @param res
* The resources object containing the image data
* @param resId
* The resource id of the image data
* @param reqWidth
* The requested width of the resulting bitmap
* @param reqHeight
* The requested height of the resulting bitmap
* @param cache
* The ImageCache used to find candidate bitmaps for use with
* inBitmap
* @return A bitmap sampled down from the original with the same aspect
* ratio and dimensions that are equal to or greater than the
* requested width and height
*/
public static Bitmap decodeSampledBitmapFromResource(Resources res,
int resId, int reqWidth, int reqHeight, ImageCache cache) {
// BEGIN_INCLUDE (read_bitmap_dimensions)
// First decode with inJustDecodeBounds=true to check dimensions
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeResource(res, resId, options);
// Calculate inSampleSize
options.inSampleSize = calculateInSampleSize(options, reqWidth,
reqHeight);
// END_INCLUDE (read_bitmap_dimensions)
// If we're running on Honeycomb or newer, try to use inBitmap
if (Utils.hasHoneycomb()) {
addInBitmapOptions(options, cache);
}
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
return BitmapFactory.decodeResource(res, resId, options);
}
/**
* Decode and sample down a bitmap from a file to the requested width and
* height.
*
* @param filename
* The full path of the file to decode
* @param reqWidth
* The requested width of the resulting bitmap
* @param reqHeight
* The requested height of the resulting bitmap
* @param cache
* The ImageCache used to find candidate bitmaps for use with
* inBitmap
* @return A bitmap sampled down from the original with the same aspect
* ratio and dimensions that are equal to or greater than the
* requested width and height
*/
public static Bitmap decodeSampledBitmapFromFile(String filename,
int reqWidth, int reqHeight, ImageCache cache) {
// First decode with inJustDecodeBounds=true to check dimensions
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFile(filename, options);
// Calculate inSampleSize
options.inSampleSize = calculateInSampleSize(options, reqWidth,
reqHeight);
// If we're running on Honeycomb or newer, try to use inBitmap
if (Utils.hasHoneycomb()) {
addInBitmapOptions(options, cache);
}
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
return BitmapFactory.decodeFile(filename, options);
}
/**
* Decode and sample down a bitmap from a file input stream to the requested
* width and height.
*
* @param fileDescriptor
* The file descriptor to read from
* @param reqWidth
* The requested width of the resulting bitmap
* @param reqHeight
* The requested height of the resulting bitmap
* @param cache
* The ImageCache used to find candidate bitmaps for use with
* inBitmap
* @return A bitmap sampled down from the original with the same aspect
* ratio and dimensions that are equal to or greater than the
* requested width and height
*/
public static Bitmap decodeSampledBitmapFromDescriptor(
FileDescriptor fileDescriptor, int reqWidth, int reqHeight,
ImageCache cache) {
// First decode with inJustDecodeBounds=true to check dimensions
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFileDescriptor(fileDescriptor, null, options);
// Calculate inSampleSize
options.inSampleSize = calculateInSampleSize(options, reqWidth,
reqHeight);
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
// If we're running on Honeycomb or newer, try to use inBitmap
if (Utils.hasHoneycomb()) {
addInBitmapOptions(options, cache);
}
return BitmapFactory
.decodeFileDescriptor(fileDescriptor, null, options);
}
@TargetApi(Build.VERSION_CODES.HONEYCOMB)
private static void addInBitmapOptions(BitmapFactory.Options options,
ImageCache cache) {
// BEGIN_INCLUDE(add_bitmap_options)
// inBitmap only works with mutable bitmaps so force the decoder to
// return mutable bitmaps.
options.inMutable = true;
if (cache != null) {
// Try and find a bitmap to use for inBitmap
Bitmap inBitmap = cache.getBitmapFromReusableSet(options);
if (inBitmap != null) {
options.inBitmap = inBitmap;
}
}
// END_INCLUDE(add_bitmap_options)
}
/**
* Calculate an inSampleSize for use in a
* {@link BitmapFactory.Options} object when decoding
* bitmaps using the decode* methods from
* {@link BitmapFactory}. This implementation calculates
* the closest inSampleSize that is a power of 2 and will result in the
* final decoded bitmap having a width and height equal to or larger than
* the requested width and height.
*
* @param options
* An options object with out* params already populated (run
* through a decode* method with inJustDecodeBounds==true
* @param reqWidth
* The requested width of the resulting bitmap
* @param reqHeight
* The requested height of the resulting bitmap
* @return The value to be used for inSampleSize
*/
public static int calculateInSampleSize(BitmapFactory.Options options,
int reqWidth, int reqHeight) {
// BEGIN_INCLUDE (calculate_sample_size)
// Raw height and width of image
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth) {
final int halfHeight = height / 2;
final int halfWidth = width / 2;
// Calculate the largest inSampleSize value that is a power of 2 and
// keeps both
// height and width larger than the requested height and width.
while ((halfHeight / inSampleSize) > reqHeight
&& (halfWidth / inSampleSize) > reqWidth) {
inSampleSize *= 2;
}
// This offers some additional logic in case the image has a strange
// aspect ratio. For example, a panorama may have a much larger
// width than height. In these cases the total pixels might still
// end up being too large to fit comfortably in memory, so we should
// be more aggressive with sample down the image (=larger
// inSampleSize).
long totalPixels = width * height / inSampleSize;
// Anything more than 2x the requested pixels we'll sample down
// further
final long totalReqPixelsCap = reqWidth * reqHeight * 2;
while (totalPixels > totalReqPixelsCap) {
inSampleSize *= 2;
totalPixels /= 2;
}
}
return inSampleSize;
// END_INCLUDE (calculate_sample_size)
}
}