| /* |
| * 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_ |