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diff --git a/media/libstagefright/omx/GraphicBufferSource.h b/media/libstagefright/omx/GraphicBufferSource.h
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+++ b/media/libstagefright/omx/GraphicBufferSource.h
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+/*
+ * Copyright (C) 2013 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.
+ */
+
+#ifndef GRAPHIC_BUFFER_SOURCE_H_
+
+#define GRAPHIC_BUFFER_SOURCE_H_
+
+#include <gui/IGraphicBufferProducer.h>
+#include <gui/BufferQueue.h>
+#include <utils/RefBase.h>
+
+#include <OMX_Core.h>
+#include "../include/OMXNodeInstance.h"
+#include <media/stagefright/foundation/ABase.h>
+
+namespace android {
+
+/*
+ * This class is used to feed OMX codecs from a Surface via BufferQueue.
+ *
+ * Instances of the class don't run on a dedicated thread.  Instead,
+ * various events trigger data movement:
+ *
+ *  - Availability of a new frame of data from the BufferQueue (notified
+ *    via the onFrameAvailable callback).
+ *  - The return of a codec buffer (via OnEmptyBufferDone).
+ *  - Application signaling end-of-stream.
+ *  - Transition to or from "executing" state.
+ *
+ * Frames of data (and, perhaps, the end-of-stream indication) can arrive
+ * before the codec is in the "executing" state, so we need to queue
+ * things up until we're ready to go.
+ */
+class GraphicBufferSource : public BufferQueue::ConsumerListener {
+public:
+    GraphicBufferSource(OMXNodeInstance* nodeInstance,
+            uint32_t bufferWidth, uint32_t bufferHeight);
+    virtual ~GraphicBufferSource();
+
+    // We can't throw an exception if the constructor fails, so we just set
+    // this and require that the caller test the value.
+    status_t initCheck() const {
+        return mInitCheck;
+    }
+
+    // Returns the handle to the producer side of the BufferQueue.  Buffers
+    // queued on this will be received by GraphicBufferSource.
+    sp<IGraphicBufferProducer> getIGraphicBufferProducer() const {
+        return mBufferQueue;
+    }
+
+    // This is called when OMX transitions to OMX_StateExecuting, which means
+    // we can start handing it buffers.  If we already have buffers of data
+    // sitting in the BufferQueue, this will send them to the codec.
+    void omxExecuting();
+
+    // This is called when OMX transitions to OMX_StateIdle.  If we were
+    // previously executing, this means we're about to be shut down.  (We
+    // also enter Idle on the way up.)
+    void omxIdling();
+
+    // A "codec buffer", i.e. a buffer that can be used to pass data into
+    // the encoder, has been allocated.  (This call does not call back into
+    // OMXNodeInstance.)
+    void addCodecBuffer(OMX_BUFFERHEADERTYPE* header);
+
+    // Called from OnEmptyBufferDone.  If we have a BQ buffer available,
+    // fill it with a new frame of data; otherwise, just mark it as available.
+    void codecBufferEmptied(OMX_BUFFERHEADERTYPE* header);
+
+    // This is called after the last input frame has been submitted.  We
+    // need to submit an empty buffer with the EOS flag set.  If we don't
+    // have a codec buffer ready, we just set the mEndOfStream flag.
+    void signalEndOfInputStream();
+
+protected:
+    // BufferQueue::ConsumerListener interface, called when a new frame of
+    // data is available.  If we're executing and a codec buffer is
+    // available, we acquire the buffer, copy the GraphicBuffer reference
+    // into the codec buffer, and call Empty[This]Buffer.  If we're not yet
+    // executing or there's no codec buffer available, we just increment
+    // mNumFramesAvailable and return.
+    virtual void onFrameAvailable();
+
+    // BufferQueue::ConsumerListener interface, called when the client has
+    // released one or more GraphicBuffers.  We clear out the appropriate
+    // set of mBufferSlot entries.
+    virtual void onBuffersReleased();
+
+private:
+    // Keep track of codec input buffers.  They may either be available
+    // (mGraphicBuffer == NULL) or in use by the codec.
+    struct CodecBuffer {
+        OMX_BUFFERHEADERTYPE* mHeader;
+        sp<GraphicBuffer> mGraphicBuffer;
+    };
+
+    // Returns the index of an available codec buffer.  If none are
+    // available, returns -1.  Mutex must be held by caller.
+    int findAvailableCodecBuffer_l();
+
+    // Returns true if a codec buffer is available.
+    bool isCodecBufferAvailable_l() {
+        return findAvailableCodecBuffer_l() >= 0;
+    }
+
+    // Finds the mCodecBuffers entry that matches.  Returns -1 if not found.
+    int findMatchingCodecBuffer_l(const OMX_BUFFERHEADERTYPE* header);
+
+    // Fills a codec buffer with a frame from the BufferQueue.  This must
+    // only be called when we know that a frame of data is ready (i.e. we're
+    // in the onFrameAvailable callback, or if we're in codecBufferEmptied
+    // and mNumFramesAvailable is nonzero).  Returns without doing anything if
+    // we don't have a codec buffer available.
+    status_t fillCodecBuffer_l();
+
+    // Marks the mCodecBuffers entry as in-use, copies the GraphicBuffer
+    // reference into the codec buffer, and submits the data to the codec.
+    status_t submitBuffer_l(sp<GraphicBuffer>& graphicBuffer,
+            int64_t timestamp, int cbi);
+
+    // Submits an empty buffer, with the EOS flag set.   Returns without
+    // doing anything if we don't have a codec buffer available.
+    void submitEndOfInputStream_l();
+
+    // Lock, covers all member variables.
+    mutable Mutex mMutex;
+
+    // Used to report constructor failure.
+    status_t mInitCheck;
+
+    // Pointer back to the object that contains us.  We send buffers here.
+    OMXNodeInstance* mNodeInstance;
+
+    // Set by omxExecuting() / omxIdling().
+    bool mExecuting;
+
+    // We consume graphic buffers from this.
+    sp<BufferQueue> mBufferQueue;
+
+    // Number of frames pending in BufferQueue that haven't yet been
+    // forwarded to the codec.
+    size_t mNumFramesAvailable;
+
+    // Set to true if we want to send end-of-stream after we run out of
+    // frames in BufferQueue.
+    bool mEndOfStream;
+    bool mEndOfStreamSent;
+
+    // Cache of GraphicBuffers from the buffer queue.  When the codec
+    // is done processing a GraphicBuffer, we can use this to map back
+    // to a slot number.
+    sp<GraphicBuffer> mBufferSlot[BufferQueue::NUM_BUFFER_SLOTS];
+
+    // Tracks codec buffers.
+    Vector<CodecBuffer> mCodecBuffers;
+
+    DISALLOW_EVIL_CONSTRUCTORS(GraphicBufferSource);
+};
+
+}  // namespace android
+
+#endif  // GRAPHIC_BUFFER_SOURCE_H_