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diff --git a/include/media/stagefright/VideoSourceDownSampler.h b/include/media/stagefright/VideoSourceDownSampler.h
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+/*
+ * Copyright (C) 2010 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.
+ */
+
+// VideoSourceDownSampler implements the MediaSource interface,
+// downsampling frames provided from a real video source.
+
+#ifndef VIDEO_SOURCE_DOWN_SAMPLER_H_
+
+#define VIDEO_SOURCE_DOWN_SAMPLER_H_
+
+#include <media/stagefright/MediaSource.h>
+#include <utils/RefBase.h>
+
+namespace android {
+
+class IMemory;
+class MediaBuffer;
+class MetaData;
+
+class VideoSourceDownSampler : public MediaSource {
+public:
+    virtual ~VideoSourceDownSampler();
+
+    // Constructor:
+    // videoSource: The real video source which provides the original frames.
+    // width, height: The desired width, height. These should be less than or equal
+    // to those of the real video source. We then downsample the original frames to
+    // this size.
+    VideoSourceDownSampler(const sp<MediaSource> &videoSource,
+        int32_t width, int32_t height);
+
+    // MediaSource interface
+    virtual status_t start(MetaData *params = NULL);
+
+    virtual status_t stop();
+
+    virtual sp<MetaData> getFormat();
+
+    virtual status_t read(
+            MediaBuffer **buffer, const ReadOptions *options = NULL);
+
+    virtual status_t pause();
+
+private:
+    // Reference to the real video source.
+    sp<MediaSource> mRealVideoSource;
+
+    // Size of frames to be provided by this source.
+    int32_t mWidth;
+    int32_t mHeight;
+
+    // Size of frames provided by the real source.
+    int32_t mRealSourceWidth;
+    int32_t mRealSourceHeight;
+
+    // Down sampling paramters.
+    int32_t mDownSampleOffsetX;
+    int32_t mDownSampleOffsetY;
+    int32_t mDownSampleSkipX;
+    int32_t mDownSampleSkipY;
+
+    // True if we need to crop the still video image to get the video frame.
+    bool mNeedDownSampling;
+
+    // Meta data. This is a copy of the real source except for the width and
+    // height parameters.
+    sp<MetaData> mMeta;
+
+    // Computes the offset, skip parameters for downsampling the original frame
+    // to the desired size.
+    void computeDownSamplingParameters();
+
+    // Downsamples the frame in sourceBuffer to size (mWidth x mHeight). A new
+    // buffer is created which stores the downsampled image.
+    void downSampleYUVImage(const MediaBuffer &sourceBuffer, MediaBuffer **buffer) const;
+
+    // Disallow these.
+    VideoSourceDownSampler(const VideoSourceDownSampler &);
+    VideoSourceDownSampler &operator=(const VideoSourceDownSampler &);
+};
+
+}  // namespace android
+
+#endif  // VIDEO_SOURCE_DOWN_SAMPLER_H_