Do JPEG tile-based decoding.

Change-Id: I5c1b4ac3c02eb4350ef0ba9a7877b22cfd730cfb

2 files changed, 271 insertions, 0 deletions

diff --git a/graphics/java/android/graphics/BitmapFactory.java b/graphics/java/android/graphics/BitmapFactory.java
index 2313f4c..8982388 100644
--- a/graphics/java/android/graphics/BitmapFactory.java
+++ b/graphics/java/android/graphics/BitmapFactory.java
@@ -27,6 +27,7 @@ import java.io.FileDescriptor;
 import java.io.FileInputStream;
 import java.io.IOException;
 import java.io.InputStream;
+import java.io.FileNotFoundException;
 
 /**
  * Creates Bitmap objects from various sources, including files, streams,
@@ -581,6 +582,139 @@ public class BitmapFactory {
         nativeSetDefaultConfig(config.nativeInt);
     }
 
+    /**
+     * Create a LargeBitmap from the specified byte array.
+     * Currently only the Jpeg format is supported.
+     *
+     * @param data byte array of compressed image data.
+     * @param offset offset into data for where the decoder should begin
+     *               parsing.
+     * @param length the number of bytes, beginning at offset, to parse
+     * @param isShareable If this is true, then the LargeBitmap may keep a
+     *                    shallow reference to the input. If this is false,
+     *                    then the LargeBitmap will explicitly make a copy of the
+     *                    input data, and keep that. Even if sharing is allowed,
+     *                    the implementation may still decide to make a deep
+     *                    copy of the input data. If an image is progressively encoded,
+     *                    allowing sharing may degrade the decoding speed.
+     * @return LargeBitmap, or null if the image data could not be decoded.
+     * @throws IOException if the image format is not supported or can not be decoded.
+     * @hide
+     */
+    public static LargeBitmap createLargeBitmap(byte[] data,
+            int offset, int length, boolean isShareable) throws IOException {
+        if ((offset | length) < 0 || data.length < offset + length) {
+            throw new ArrayIndexOutOfBoundsException();
+        }
+        return nativeCreateLargeBitmap(data, offset, length, isShareable);
+    }
+
+    /**
+     * Create a LargeBitmap from the file descriptor.
+     * The position within the descriptor will not be changed when
+     * this returns, so the descriptor can be used again as is.
+     * Currently only the Jpeg format is supported.
+     *
+     * @param fd The file descriptor containing the data to decode
+     * @param isShareable If this is true, then the LargeBitmap may keep a
+     *                    shallow reference to the input. If this is false,
+     *                    then the LargeBitmap will explicitly make a copy of the
+     *                    input data, and keep that. Even if sharing is allowed,
+     *                    the implementation may still decide to make a deep
+     *                    copy of the input data. If an image is progressively encoded,
+     *                    allowing sharing may degrade the decoding speed.
+     * @return LargeBitmap, or null if the image data could not be decoded.
+     * @throws IOException if the image format is not supported or can not be decoded.
+     * @hide
+     */
+    public static LargeBitmap createLargeBitmap(
+            FileDescriptor fd, boolean isShareable) throws IOException {
+        if (MemoryFile.isMemoryFile(fd)) {
+            int mappedlength = MemoryFile.getSize(fd);
+            MemoryFile file = new MemoryFile(fd, mappedlength, "r");
+            InputStream is = file.getInputStream();
+            return createLargeBitmap(is, isShareable);
+        }
+        return nativeCreateLargeBitmap(fd, isShareable);
+    }
+
+    /**
+     * Create a LargeBitmap from an input stream.
+     * The stream's position will be where ever it was after the encoded data
+     * was read.
+     * Currently only the Jpeg format is supported.
+     *
+     * @param is The input stream that holds the raw data to be decoded into a
+     *           LargeBitmap.
+     * @param isShareable If this is true, then the LargeBitmap may keep a
+     *                    shallow reference to the input. If this is false,
+     *                    then the LargeBitmap will explicitly make a copy of the
+     *                    input data, and keep that. Even if sharing is allowed,
+     *                    the implementation may still decide to make a deep
+     *                    copy of the input data. If an image is progressively encoded,
+     *                    allowing sharing may degrade the decoding speed.
+     * @return LargeBitmap, or null if the image data could not be decoded.
+     * @throws IOException if the image format is not supported or can not be decoded.
+     * @hide
+     */
+    public static LargeBitmap createLargeBitmap(InputStream is,
+            boolean isShareable) throws IOException {
+        // we need mark/reset to work properly in JNI
+
+        if (!is.markSupported()) {
+            is = new BufferedInputStream(is, 16 * 1024);
+        }
+
+        if (is instanceof AssetManager.AssetInputStream) {
+            return nativeCreateLargeBitmap(
+                    ((AssetManager.AssetInputStream) is).getAssetInt(),
+                    isShareable);
+        } else {
+            // pass some temp storage down to the native code. 1024 is made up,
+            // but should be large enough to avoid too many small calls back
+            // into is.read(...).
+            byte [] tempStorage = null;
+            tempStorage = new byte[16 * 1024];
+            return nativeCreateLargeBitmap(is, tempStorage, isShareable);
+        }
+    }
+
+    /**
+     * Create a LargeBitmap from a file path.
+     * Currently only the Jpeg format is supported.
+     *
+     * @param pathName complete path name for the file to be decoded.
+     * @param isShareable If this is true, then the LargeBitmap may keep a
+     *                    shallow reference to the input. If this is false,
+     *                    then the LargeBitmap will explicitly make a copy of the
+     *                    input data, and keep that. Even if sharing is allowed,
+     *                    the implementation may still decide to make a deep
+     *                    copy of the input data. If an image is progressively encoded,
+     *                    allowing sharing may degrade the decoding speed.
+     * @return LargeBitmap, or null if the image data could not be decoded.
+     * @throws IOException if the image format is not supported or can not be decoded.
+     * @hide
+     */
+    public static LargeBitmap createLargeBitmap(String pathName,
+            boolean isShareable) throws FileNotFoundException, IOException {
+        LargeBitmap bm = null;
+        InputStream stream = null;
+
+        try {
+            stream = new FileInputStream(pathName);
+            bm = createLargeBitmap(stream, isShareable);
+        } finally {
+            if (stream != null) {
+                try {
+                    stream.close();
+                } catch (IOException e) {
+                    // do nothing here
+                }
+            }
+        }
+        return bm;
+    }
+
     private static native void nativeSetDefaultConfig(int nativeConfig);
     private static native Bitmap nativeDecodeStream(InputStream is, byte[] storage,
             Rect padding, Options opts);
@@ -590,5 +724,14 @@ public class BitmapFactory {
     private static native Bitmap nativeDecodeByteArray(byte[] data, int offset,
             int length, Options opts);
     private static native byte[] nativeScaleNinePatch(byte[] chunk, float scale, Rect pad);
+
+    private static native LargeBitmap nativeCreateLargeBitmap(
+            byte[] data, int offset, int length, boolean isShareable);
+    private static native LargeBitmap nativeCreateLargeBitmap(
+            FileDescriptor fd, boolean isShareable);
+    private static native LargeBitmap nativeCreateLargeBitmap(
+            InputStream is, byte[] storage, boolean isShareable);
+    private static native LargeBitmap nativeCreateLargeBitmap(
+            int asset, boolean isShareable);
 }
 
diff --git a/graphics/java/android/graphics/LargeBitmap.java b/graphics/java/android/graphics/LargeBitmap.java
new file mode 100644
index 0000000..6656b17
--- /dev/null
+++ b/graphics/java/android/graphics/LargeBitmap.java
@@ -0,0 +1,128 @@
+/*
+ * Copyright (C) 2006 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.graphics;
+
+import android.os.Parcel;
+import android.os.Parcelable;
+import android.util.DisplayMetrics;
+
+import java.io.OutputStream;
+import java.nio.Buffer;
+import java.nio.ByteBuffer;
+import java.nio.IntBuffer;
+import java.nio.ShortBuffer;
+
+/**
+ * LargeBitmap can be used to decode a rectangle region from an image.
+ * LargeBimap is particularly useful when an original image is large and
+ * you only need parts of the image.
+ *
+ * To create a LargeBitmap, call BitmapFactory.createLargeBitmap().
+ * Given a LargeBitmap, users can call decodeRegion() repeatedly
+ * to get a decoded Bitmap of the specified region.
+ * @hide
+ */
+public final class LargeBitmap {
+    private int mNativeLargeBitmap;
+    private boolean mRecycled;
+
+    /*  Private constructor that must received an already allocated native
+        large bitmap int (pointer).
+
+        This can be called from JNI code.
+    */
+    private LargeBitmap(int lbm) {
+        mNativeLargeBitmap = lbm;
+        mRecycled = false;
+    }
+
+    /**
+     * Decodes a rectangle region in the image specified by rect.
+     *
+     * @param rect The rectangle that specified the region to be decode.
+     * @param opts null-ok; Options that control downsampling.
+     *             inPurgeable is not supported.
+     * @return The decoded bitmap, or null if the image data could not be
+     *         decoded.
+     */
+    public Bitmap decodeRegion(Rect rect, BitmapFactory.Options options) {
+        checkRecycled("decodeRegion called on recycled large bitmap");
+        if (rect.left < 0 || rect.top < 0 || rect.right > getWidth() || rect.bottom > getHeight())
+            throw new IllegalArgumentException("rectangle is not inside the image");
+        return nativeDecodeRegion(mNativeLargeBitmap, rect.left, rect.top,
+                rect.right - rect.left, rect.bottom - rect.top, options);
+    }
+
+    /** Returns the original image's width */
+    public int getWidth() {
+        checkRecycled("getWidth called on recycled large bitmap");
+        return nativeGetWidth(mNativeLargeBitmap);
+    }
+
+    /** Returns the original image's height */
+    public int getHeight() {
+        checkRecycled("getHeight called on recycled large bitmap");
+        return nativeGetHeight(mNativeLargeBitmap);
+    }
+
+    /**
+     * Frees up the memory associated with this large bitmap, and mark the
+     * large bitmap as "dead", meaning it will throw an exception if decodeRegion(),
+     * getWidth() or getHeight() is called.
+     * This operation cannot be reversed, so it should only be called if you are
+     * sure there are no further uses for the large bitmap. This is an advanced call,
+     * and normally need not be called, since the normal GC process will free up this
+     * memory when there are no more references to this bitmap.
+     */
+    public void recycle() {
+        if (!mRecycled) {
+            nativeClean(mNativeLargeBitmap);
+            mRecycled = true;
+        }
+    }
+
+    /**
+     * Returns true if this large bitmap has been recycled.
+     * If so, then it is an error to try use its method.
+     *
+     * @return true if the large bitmap has been recycled
+     */
+    public final boolean isRecycled() {
+        return mRecycled;
+    }
+
+    /**
+     * Called by methods that want to throw an exception if the bitmap
+     * has already been recycled.
+     */
+    private void checkRecycled(String errorMessage) {
+        if (mRecycled) {
+            throw new IllegalStateException(errorMessage);
+        }
+    }
+
+    protected void finalize() {
+        recycle();
+    }
+
+    private static native Bitmap nativeDecodeRegion(int lbm,
+            int start_x, int start_y, int width, int height,
+            BitmapFactory.Options options);
+    private static native int nativeGetWidth(int lbm);
+    private static native int nativeGetHeight(int lbm);
+    private static native void nativeClean(int lbm);
+}