diff --git a/api/current.txt b/api/current.txt
index 9968258..bb8c7b0 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -13646,22 +13646,22 @@
     method public int getAllocator();
     method public boolean getConserveMemory();
     method public android.graphics.Rect getCrop();
-    method public boolean getDecodeAsAlphaMask();
-    method public boolean getMutable();
     method public android.graphics.ImageDecoder.OnPartialImageListener getOnPartialImageListener();
     method public android.graphics.PostProcessor getPostProcessor();
-    method public boolean getRequireUnpremultiplied();
+    method public boolean isDecodeAsAlphaMaskEnabled();
+    method public boolean isMutableRequired();
+    method public boolean isUnpremultipliedRequired();
     method public android.graphics.ImageDecoder setAllocator(int);
     method public android.graphics.ImageDecoder setConserveMemory(boolean);
     method public android.graphics.ImageDecoder setCrop(android.graphics.Rect);
-    method public android.graphics.ImageDecoder setDecodeAsAlphaMask(boolean);
-    method public android.graphics.ImageDecoder setMutable(boolean);
+    method public android.graphics.ImageDecoder setDecodeAsAlphaMaskEnabled(boolean);
+    method public android.graphics.ImageDecoder setMutableRequired(boolean);
     method public android.graphics.ImageDecoder setOnPartialImageListener(android.graphics.ImageDecoder.OnPartialImageListener);
     method public android.graphics.ImageDecoder setPostProcessor(android.graphics.PostProcessor);
-    method public android.graphics.ImageDecoder setRequireUnpremultiplied(boolean);
     method public android.graphics.ImageDecoder setTargetColorSpace(android.graphics.ColorSpace);
     method public android.graphics.ImageDecoder setTargetSampleSize(int);
     method public android.graphics.ImageDecoder setTargetSize(int, int);
+    method public android.graphics.ImageDecoder setUnpremultipliedRequired(boolean);
     field public static final int ALLOCATOR_DEFAULT = 0; // 0x0
     field public static final int ALLOCATOR_HARDWARE = 3; // 0x3
     field public static final int ALLOCATOR_SHARED_MEMORY = 2; // 0x2
diff --git a/api/removed.txt b/api/removed.txt
index 5863e77..2d76c5a 100644
--- a/api/removed.txt
+++ b/api/removed.txt
@@ -183,7 +183,13 @@
 
   public final class ImageDecoder implements java.lang.AutoCloseable {
     method public deprecated boolean getAsAlphaMask();
+    method public deprecated boolean getDecodeAsAlphaMask();
+    method public deprecated boolean getMutable();
+    method public deprecated boolean getRequireUnpremultiplied();
     method public deprecated android.graphics.ImageDecoder setAsAlphaMask(boolean);
+    method public deprecated android.graphics.ImageDecoder setDecodeAsAlphaMask(boolean);
+    method public deprecated android.graphics.ImageDecoder setMutable(boolean);
+    method public deprecated android.graphics.ImageDecoder setRequireUnpremultiplied(boolean);
     method public deprecated android.graphics.ImageDecoder setResize(int, int);
     method public deprecated android.graphics.ImageDecoder setResize(int);
     field public static final deprecated int ERROR_SOURCE_ERROR = 3; // 0x3
diff --git a/graphics/java/android/graphics/ImageDecoder.java b/graphics/java/android/graphics/ImageDecoder.java
index 6051f88..5261c04 100644
--- a/graphics/java/android/graphics/ImageDecoder.java
+++ b/graphics/java/android/graphics/ImageDecoder.java
@@ -21,10 +21,12 @@
 
 import static java.lang.annotation.RetentionPolicy.SOURCE;
 
+import android.annotation.AnyThread;
 import android.annotation.IntDef;
 import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.annotation.TestApi;
+import android.annotation.WorkerThread;
 import android.content.ContentResolver;
 import android.content.res.AssetFileDescriptor;
 import android.content.res.AssetManager;
@@ -65,6 +67,16 @@
 
     /**
      *  Source of the encoded image data.
+     *
+     *  <p>This object references the data that will be used to decode a
+     *  Drawable or Bitmap in {@link #decodeDrawable} or {@link #decodeBitmap}.
+     *  Constructing a {@code Source} (with one of the overloads of
+     *  {@code createSource}) can be done on any thread because the construction
+     *  simply captures values. The real work is done in decodeDrawable or
+     *  decodeBitmap.</p>
+     *
+     *  <p>Further, a Source object can be reused with different settings, or
+     *  even used simultaneously in multiple threads.</p>
      */
     public static abstract class Source {
         private Source() {}
@@ -120,7 +132,8 @@
                 int length = mBuffer.limit() - mBuffer.position();
                 return nCreate(mBuffer.array(), offset, length, this);
             }
-            return nCreate(mBuffer, mBuffer.position(), mBuffer.limit(), this);
+            ByteBuffer buffer = mBuffer.slice();
+            return nCreate(buffer, buffer.position(), buffer.limit(), this);
         }
     }
 
@@ -232,6 +245,8 @@
 
     /**
      * For backwards compatibility, this does *not* close the InputStream.
+     *
+     * Further, unlike other Sources, this one is not reusable.
      */
     private static class InputStreamSource extends Source {
         InputStreamSource(Resources res, InputStream is, int inputDensity) {
@@ -322,12 +337,17 @@
         final Resources mResources;
         final int       mResId;
         int             mResDensity;
+        private Object  mLock = new Object();
 
         @Override
         public Resources getResources() { return mResources; }
 
         @Override
-        public int getDensity() { return mResDensity; }
+        public int getDensity() {
+            synchronized (mLock) {
+                return mResDensity;
+            }
+        }
 
         @Override
         public ImageDecoder createImageDecoder() throws IOException {
@@ -336,10 +356,12 @@
             // keep it alive.
             InputStream is = mResources.openRawResource(mResId, value);
 
-            if (value.density == TypedValue.DENSITY_DEFAULT) {
-                mResDensity = DisplayMetrics.DENSITY_DEFAULT;
-            } else if (value.density != TypedValue.DENSITY_NONE) {
-                mResDensity = value.density;
+            synchronized (mLock) {
+                if (value.density == TypedValue.DENSITY_DEFAULT) {
+                    mResDensity = DisplayMetrics.DENSITY_DEFAULT;
+                } else if (value.density != TypedValue.DENSITY_NONE) {
+                    mResDensity = value.density;
+                }
             }
 
             return createFromAsset((AssetInputStream) is, this);
@@ -455,6 +477,9 @@
     /**
      *  Optional listener supplied to {@link #decodeDrawable} or
      *  {@link #decodeBitmap}.
+     *
+     *  <p>This is necessary in order to change the default settings of the
+     *  decode.</p>
      */
     public static interface OnHeaderDecodedListener {
         /**
@@ -546,6 +571,9 @@
 
         /**
          *  Retrieve the {@link Source} that was interrupted.
+         *
+         *  <p>This can be used for equality checking to find the Source which
+         *  failed to completely decode.</p>
          */
         @NonNull
         public Source getSource() {
@@ -597,7 +625,7 @@
     private int        mDesiredWidth;
     private int        mDesiredHeight;
     private int        mAllocator = ALLOCATOR_DEFAULT;
-    private boolean    mRequireUnpremultiplied = false;
+    private boolean    mUnpremultipliedRequired = false;
     private boolean    mMutable = false;
     private boolean    mConserveMemory = false;
     private boolean    mDecodeAsAlphaMask = false;
@@ -658,6 +686,7 @@
      * @return a new Source object, which can be passed to
      *      {@link #decodeDrawable} or {@link #decodeBitmap}.
      */
+    @AnyThread
     @NonNull
     public static Source createSource(@NonNull Resources res, int resId)
     {
@@ -672,6 +701,7 @@
      * @return a new Source object, which can be passed to
      *      {@link #decodeDrawable} or {@link #decodeBitmap}.
      */
+    @AnyThread
     @NonNull
     public static Source createSource(@NonNull ContentResolver cr,
             @NonNull Uri uri) {
@@ -683,6 +713,7 @@
      *
      * @hide
      */
+    @AnyThread
     @NonNull
     public static Source createSource(@NonNull ContentResolver cr,
             @NonNull Uri uri, @Nullable Resources res) {
@@ -692,6 +723,7 @@
     /**
      * Create a new {@link Source} from a file in the "assets" directory.
      */
+    @AnyThread
     @NonNull
     public static Source createSource(@NonNull AssetManager assets, @NonNull String fileName) {
         return new AssetSource(assets, fileName);
@@ -709,6 +741,7 @@
      *      not within data.
      * @hide
      */
+    @AnyThread
     @NonNull
     public static Source createSource(@NonNull byte[] data, int offset,
             int length) throws ArrayIndexOutOfBoundsException {
@@ -727,6 +760,7 @@
      * See {@link #createSource(byte[], int, int).
      * @hide
      */
+    @AnyThread
     @NonNull
     public static Source createSource(@NonNull byte[] data) {
         return createSource(data, 0, data.length);
@@ -744,24 +778,35 @@
      * be modified, even after the {@code AnimatedImageDrawable} is returned.
      * {@code buffer}'s contents should never be modified during decode.</p>
      */
+    @AnyThread
     @NonNull
     public static Source createSource(@NonNull ByteBuffer buffer) {
-        return new ByteBufferSource(buffer.slice());
+        return new ByteBufferSource(buffer);
     }
 
     /**
      * Internal API used to generate bitmaps for use by Drawables (i.e. BitmapDrawable)
+     *
+     * <p>Unlike other Sources, this one cannot be reused.</p>
+     *
      * @hide
      */
+    @AnyThread
+    @NonNull
     public static Source createSource(Resources res, InputStream is) {
         return new InputStreamSource(res, is, Bitmap.getDefaultDensity());
     }
 
     /**
      * Internal API used to generate bitmaps for use by Drawables (i.e. BitmapDrawable)
+     *
+     * <p>Unlike other Sources, this one cannot be reused.</p>
+     *
      * @hide
      */
+    @AnyThread
     @TestApi
+    @NonNull
     public static Source createSource(Resources res, InputStream is, int density) {
         return new InputStreamSource(res, is, density);
     }
@@ -769,6 +814,7 @@
     /**
      * Create a new {@link Source} from a {@link java.io.File}.
      */
+    @AnyThread
     @NonNull
     public static Source createSource(@NonNull File file) {
         return new FileSource(file);
@@ -782,7 +828,7 @@
      *  height that can be achieved by sampling the encoded image. Other widths
      *  and heights may be supported, but will require an additional (internal)
      *  scaling step. Such internal scaling is *not* supported with
-     *  {@link #setRequireUnpremultiplied} set to {@code true}.</p>
+     *  {@link #setUnpremultipliedRequired} set to {@code true}.</p>
      *
      *  @param sampleSize Sampling rate of the encoded image.
      *  @return {@link android.util.Size} of the width and height after
@@ -822,6 +868,9 @@
      *  <p>Only the last call to this or {@link #setTargetSampleSize} is
      *  respected.</p>
      *
+     *  <p>Like all setters on ImageDecoder, this must be called inside
+     *  {@link OnHeaderDecodedListener#onHeaderDecoded}.</p>
+     *
      *  @param width must be greater than 0.
      *  @param height must be greater than 0.
      *  @return this object for chaining.
@@ -888,6 +937,9 @@
      *
      *  <p>Only the last call to this or {@link #setTargetSize} is respected.</p>
      *
+     *  <p>Like all setters on ImageDecoder, this must be called inside
+     *  {@link OnHeaderDecodedListener#onHeaderDecoded}.</p>
+     *
      *  @param sampleSize Sampling rate of the encoded image.
      *  @return this object for chaining.
      */
@@ -909,7 +961,7 @@
      *  Will typically result in a {@link Bitmap.Config#HARDWARE}
      *  allocation, but may be software for small images. In addition, this will
      *  switch to software when HARDWARE is incompatible, e.g.
-     *  {@link #setMutable}, {@link #setDecodeAsAlphaMask}.
+     *  {@link #setMutableRequired}, {@link #setDecodeAsAlphaMaskEnabled}.
      */
     public static final int ALLOCATOR_DEFAULT = 0;
 
@@ -932,8 +984,8 @@
      *  Require a {@link Bitmap.Config#HARDWARE} {@link Bitmap}.
      *
      *  When this is combined with incompatible options, like
-     *  {@link #setMutable} or {@link #setDecodeAsAlphaMask}, {@link #decodeDrawable}
-     *  / {@link #decodeBitmap} will throw an
+     *  {@link #setMutableRequired} or {@link #setDecodeAsAlphaMaskEnabled},
+     *  {@link #decodeDrawable} / {@link #decodeBitmap} will throw an
      *  {@link java.lang.IllegalStateException}.
      */
     public static final int ALLOCATOR_HARDWARE = 3;
@@ -948,7 +1000,10 @@
     /**
      *  Choose the backing for the pixel memory.
      *
-     *  This is ignored for animated drawables.
+     *  <p>This is ignored for animated drawables.</p>
+     *
+     *  <p>Like all setters on ImageDecoder, this must be called inside
+     *  {@link OnHeaderDecodedListener#onHeaderDecoded}.</p>
      *
      *  @param allocator Type of allocator to use.
      *  @return this object for chaining.
@@ -982,18 +1037,37 @@
      *  {@link Drawable} will throw an {@link java.lang.IllegalStateException}.
      *  </p>
      *
+     *  <p>Like all setters on ImageDecoder, this must be called inside
+     *  {@link OnHeaderDecodedListener#onHeaderDecoded}.</p>
+     *
      *  @return this object for chaining.
      */
-    public ImageDecoder setRequireUnpremultiplied(boolean requireUnpremultiplied) {
-        mRequireUnpremultiplied = requireUnpremultiplied;
+    public ImageDecoder setUnpremultipliedRequired(boolean unpremultipliedRequired) {
+        mUnpremultipliedRequired = unpremultipliedRequired;
         return this;
     }
 
+    /** @removed
+     * @deprecated Renamed to {@link #setUnpremultipliedRequired}.
+     */
+    @java.lang.Deprecated
+    public ImageDecoder setRequireUnpremultiplied(boolean unpremultipliedRequired) {
+        return this.setUnpremultipliedRequired(unpremultipliedRequired);
+    }
+
     /**
      *  Return whether the {@link Bitmap} will have unpremultiplied pixels.
      */
+    public boolean isUnpremultipliedRequired() {
+        return mUnpremultipliedRequired;
+    }
+
+    /** @removed
+     * @deprecated Renamed to {@link #isUnpremultipliedRequired}.
+     */
+    @java.lang.Deprecated
     public boolean getRequireUnpremultiplied() {
-        return mRequireUnpremultiplied;
+        return this.isUnpremultipliedRequired();
     }
 
     /**
@@ -1009,6 +1083,9 @@
      *  {@link Canvas} will be recorded immediately and then applied to each
      *  frame.</p>
      *
+     *  <p>Like all setters on ImageDecoder, this must be called inside
+     *  {@link OnHeaderDecodedListener#onHeaderDecoded}.</p>
+     *
      *  @return this object for chaining.
      */
     public ImageDecoder setPostProcessor(@Nullable PostProcessor p) {
@@ -1030,6 +1107,9 @@
      *  <p>Will be called if there is an error in the input. Without one, an
      *  error will result in an Exception being thrown.</p>
      *
+     *  <p>Like all setters on ImageDecoder, this must be called inside
+     *  {@link OnHeaderDecodedListener#onHeaderDecoded}.</p>
+     *
      *  @return this object for chaining.
      */
     public ImageDecoder setOnPartialImageListener(@Nullable OnPartialImageListener l) {
@@ -1057,6 +1137,9 @@
      *  {@link BitmapRegionDecoder#decodeRegion}. This supports all formats,
      *  but merely crops the output.</p>
      *
+     *  <p>Like all setters on ImageDecoder, this must be called inside
+     *  {@link OnHeaderDecodedListener#onHeaderDecoded}.</p>
+     *
      *  @return this object for chaining.
      */
     public ImageDecoder setCrop(@Nullable Rect subset) {
@@ -1078,6 +1161,9 @@
      *  If the image is a nine patch, this Rect will be set to the padding
      *  rectangle during decode. Otherwise it will not be modified.
      *
+     *  <p>Like all setters on ImageDecoder, this must be called inside
+     *  {@link OnHeaderDecodedListener#onHeaderDecoded}.</p>
+     *
      *  @return this object for chaining.
      *
      *  @hide
@@ -1103,20 +1189,39 @@
      *  order to modify. Attempting to decode a mutable {@link Drawable} will
      *  throw an {@link java.lang.IllegalStateException}.</p>
      *
+     *  <p>Like all setters on ImageDecoder, this must be called inside
+     *  {@link OnHeaderDecodedListener#onHeaderDecoded}.</p>
+     *
      *  @return this object for chaining.
      */
-    public ImageDecoder setMutable(boolean mutable) {
+    public ImageDecoder setMutableRequired(boolean mutable) {
         mMutable = mutable;
         return this;
     }
 
+    /** @removed
+     * @deprecated Renamed to {@link #setMutableRequired}.
+     */
+    @java.lang.Deprecated
+    public ImageDecoder setMutable(boolean mutable) {
+        return this.setMutableRequired(mutable);
+    }
+
     /**
      *  Return whether the {@link Bitmap} will be mutable.
      */
-    public boolean getMutable() {
+    public boolean isMutableRequired() {
         return mMutable;
     }
 
+    /** @removed
+     * @deprecated Renamed to {@link #isMutableRequired}.
+     */
+    @java.lang.Deprecated
+    public boolean getMutable() {
+        return this.isMutableRequired();
+    }
+
     /**
      *  Specify whether to potentially save RAM at the expense of quality.
      *
@@ -1129,6 +1234,9 @@
      *  This necessarily lowers the quality of the output, but saves half
      *  the memory used.</p>
      *
+     *  <p>Like all setters on ImageDecoder, this must be called inside
+     *  {@link OnHeaderDecodedListener#onHeaderDecoded}.</p>
+     *
      *  @return this object for chaining.
      */
     public ImageDecoder setConserveMemory(boolean conserveMemory) {
@@ -1154,20 +1262,31 @@
      *  with only one channel, treat that channel as alpha. Otherwise this call has
      *  no effect.</p>
      *
-     *  <p>setDecodeAsAlphaMask is incompatible with {@link #ALLOCATOR_HARDWARE}. Trying to
+     *  <p>This is incompatible with {@link #ALLOCATOR_HARDWARE}. Trying to
      *  combine them will result in {@link #decodeDrawable}/
      *  {@link #decodeBitmap} throwing an
      *  {@link java.lang.IllegalStateException}.</p>
      *
+     *  <p>Like all setters on ImageDecoder, this must be called inside
+     *  {@link OnHeaderDecodedListener#onHeaderDecoded}.</p>
+     *
      *  @return this object for chaining.
      */
-    public ImageDecoder setDecodeAsAlphaMask(boolean decodeAsAlphaMask) {
-        mDecodeAsAlphaMask = decodeAsAlphaMask;
+    public ImageDecoder setDecodeAsAlphaMaskEnabled(boolean enabled) {
+        mDecodeAsAlphaMask = enabled;
         return this;
     }
 
     /** @removed
-     * @deprecated Call {@link #setDecodeAsAlphaMask} instead.
+     * @deprecated Renamed to {@link #setDecodeAsAlphaMaskEnabled}.
+     */
+    @java.lang.Deprecated
+    public ImageDecoder setDecodeAsAlphaMask(boolean enabled) {
+        return this.setDecodeAsAlphaMaskEnabled(enabled);
+    }
+
+    /** @removed
+     * @deprecated Renamed to {@link #setDecodeAsAlphaMaskEnabled}.
      */
     @java.lang.Deprecated
     public ImageDecoder setAsAlphaMask(boolean asAlphaMask) {
@@ -1177,16 +1296,25 @@
     /**
      *  Return whether to treat single channel input as alpha.
      *
-     *  <p>This returns whether {@link #setDecodeAsAlphaMask} was set to {@code true}.
-     *  It may still return {@code true} even if the image has more than one
-     *  channel and therefore will not be treated as an alpha mask.</p>
+     *  <p>This returns whether {@link #setDecodeAsAlphaMaskEnabled} was set to
+     *  {@code true}. It may still return {@code true} even if the image has
+     *  more than one channel and therefore will not be treated as an alpha
+     *  mask.</p>
      */
+    public boolean isDecodeAsAlphaMaskEnabled() {
+        return mDecodeAsAlphaMask;
+    }
+
+    /** @removed
+     * @deprecated Renamed to {@link #isDecodeAsAlphaMaskEnabled}.
+     */
+    @java.lang.Deprecated
     public boolean getDecodeAsAlphaMask() {
         return mDecodeAsAlphaMask;
     }
 
     /** @removed
-     * @deprecated Call {@link #getDecodeAsAlphaMask} instead.
+     * @deprecated Renamed to {@link #isDecodeAsAlphaMaskEnabled}.
      */
     @java.lang.Deprecated
     public boolean getAsAlphaMask() {
@@ -1218,6 +1346,9 @@
      * <code>IllegalArgumentException</code> will be thrown by the decode methods
      * if calling {@link ColorSpace.Rgb#getTransferParameters()} on the
      * specified color space returns null.</p>
+     *
+     * <p>Like all setters on ImageDecoder, this must be called inside
+     * {@link OnHeaderDecodedListener#onHeaderDecoded}.</p>
      */
     public ImageDecoder setTargetColorSpace(ColorSpace colorSpace) {
         mDesiredColorSpace = colorSpace;
@@ -1259,7 +1390,7 @@
             }
         }
 
-        if (mPostProcessor != null && mRequireUnpremultiplied) {
+        if (mPostProcessor != null && mUnpremultipliedRequired) {
             throw new IllegalStateException("Cannot draw to unpremultiplied pixels!");
         }
 
@@ -1285,12 +1416,13 @@
         }
     }
 
+    @WorkerThread
     @NonNull
     private Bitmap decodeBitmapInternal() throws IOException {
         checkState();
         return nDecodeBitmap(mNativePtr, this, mPostProcessor != null,
                 mDesiredWidth, mDesiredHeight, mCropRect,
-                mMutable, mAllocator, mRequireUnpremultiplied,
+                mMutable, mAllocator, mUnpremultipliedRequired,
                 mConserveMemory, mDecodeAsAlphaMask, mDesiredColorSpace);
     }
 
@@ -1313,10 +1445,12 @@
      *  @param listener for learning the {@link ImageInfo} and changing any
      *      default settings on the {@code ImageDecoder}. This will be called on
      *      the same thread as {@code decodeDrawable} before that method returns.
+     *      This is required in order to change any of the default settings.
      *  @return Drawable for displaying the image.
      *  @throws IOException if {@code src} is not found, is an unsupported
      *      format, or cannot be decoded for any reason.
      */
+    @WorkerThread
     @NonNull
     public static Drawable decodeDrawable(@NonNull Source src,
             @NonNull OnHeaderDecodedListener listener) throws IOException {
@@ -1327,6 +1461,7 @@
         return decodeDrawableImpl(src, listener);
     }
 
+    @WorkerThread
     @NonNull
     private static Drawable decodeDrawableImpl(@NonNull Source src,
             @Nullable OnHeaderDecodedListener listener) throws IOException {
@@ -1334,7 +1469,7 @@
             decoder.mSource = src;
             decoder.callHeaderDecoded(listener, src);
 
-            if (decoder.mRequireUnpremultiplied) {
+            if (decoder.mUnpremultipliedRequired) {
                 // Though this could be supported (ignored) for opaque images,
                 // it seems better to always report this error.
                 throw new IllegalStateException("Cannot decode a Drawable " +
@@ -1387,8 +1522,18 @@
     }
 
     /**
-     * See {@link #decodeDrawable(Source, OnHeaderDecodedListener)}.
+     *  Create a {@link Drawable} from a {@code Source}.
+     *
+     *  <p>Since there is no {@link OnHeaderDecodedListener}, the default
+     *  settings will be used. In order to change any settings, call
+     *  {@link #decodeDrawable(Source, OnHeaderDecodedListener)} instead.</p>
+     *
+     *  @param src representing the encoded image.
+     *  @return Drawable for displaying the image.
+     *  @throws IOException if {@code src} is not found, is an unsupported
+     *      format, or cannot be decoded for any reason.
      */
+    @WorkerThread
     @NonNull
     public static Drawable decodeDrawable(@NonNull Source src)
             throws IOException {
@@ -1402,10 +1547,12 @@
      *  @param listener for learning the {@link ImageInfo} and changing any
      *      default settings on the {@code ImageDecoder}. This will be called on
      *      the same thread as {@code decodeBitmap} before that method returns.
+     *      This is required in order to change any of the default settings.
      *  @return Bitmap containing the image.
      *  @throws IOException if {@code src} is not found, is an unsupported
      *      format, or cannot be decoded for any reason.
      */
+    @WorkerThread
     @NonNull
     public static Bitmap decodeBitmap(@NonNull Source src,
             @NonNull OnHeaderDecodedListener listener) throws IOException {
@@ -1416,6 +1563,7 @@
         return decodeBitmapImpl(src, listener);
     }
 
+    @WorkerThread
     @NonNull
     private static Bitmap decodeBitmapImpl(@NonNull Source src,
             @Nullable OnHeaderDecodedListener listener) throws IOException {
@@ -1487,8 +1635,18 @@
     }
 
     /**
-     *  See {@link #decodeBitmap(Source, OnHeaderDecodedListener)}.
+     *  Create a {@link Bitmap} from a {@code Source}.
+     *
+     *  <p>Since there is no {@link OnHeaderDecodedListener}, the default
+     *  settings will be used. In order to change any settings, call
+     *  {@link #decodeBitmap(Source, OnHeaderDecodedListener)} instead.</p>
+     *
+     *  @param src representing the encoded image.
+     *  @return Bitmap containing the image.
+     *  @throws IOException if {@code src} is not found, is an unsupported
+     *      format, or cannot be decoded for any reason.
      */
+    @WorkerThread
     @NonNull
     public static Bitmap decodeBitmap(@NonNull Source src) throws IOException {
         return decodeBitmapImpl(src, null);
@@ -1534,7 +1692,7 @@
             boolean doPostProcess,
             int width, int height,
             @Nullable Rect cropRect, boolean mutable,
-            int allocator, boolean requireUnpremul,
+            int allocator, boolean unpremulRequired,
             boolean conserveMemory, boolean decodeAsAlphaMask,
             @Nullable ColorSpace desiredColorSpace)
         throws IOException;