am 5a905ceb: Merge "Track maximum amplitude and fix getMaxAmplitude()" into gingerbread

Merge commit '5a905ceb063bd31170d3d869efcd051cbd8e4e13' into gingerbread-plus-aosp

* commit '5a905ceb063bd31170d3d869efcd051cbd8e4e13':
  Track maximum amplitude and fix getMaxAmplitude()

include/media/stagefright/AudioSource.h

@@ -39,6 +39,9 @@ struct AudioSource : public MediaSource {
     virtual status_t stop();
     virtual sp<MetaData> getFormat();
 
+    // Returns the maximum amplitude since last call.
+    int16_t getMaxAmplitude();
+
     virtual status_t read(
             MediaBuffer **buffer, const ReadOptions *options = NULL);
 
@@ -53,13 +56,17 @@ private:
     bool mStarted;
 
     bool mCollectStats;
+    bool mTrackMaxAmplitude;
     int64_t mTotalReadTimeUs;
     int64_t mTotalReadBytes;
     int64_t mTotalReads;
     int64_t mStartTimeUs;
+    int16_t mMaxAmplitude;
 
     MediaBufferGroup *mGroup;
 
+    void trackMaxAmplitude(int16_t *data, int nSamples);
+
     AudioSource(const AudioSource &);
     AudioSource &operator=(const AudioSource &);
 };

media/libmediaplayerservice/StagefrightRecorder.cpp

@@ -484,6 +484,7 @@ sp<MediaSource> StagefrightRecorder::createAudioSource() {
     sp<MediaSource> audioEncoder =
         OMXCodec::Create(client.interface(), encMeta,
                          true /* createEncoder */, audioSource);
+    mAudioSourceNode = audioSource;
 
     return audioEncoder;
 }
@@ -822,6 +823,7 @@ status_t StagefrightRecorder::reset() {
     mAudioBitRate  = 12200;
     mInterleaveDurationUs = 0;
     mIFramesInterval = 1;
+    mAudioSourceNode = 0;
     mEncoderProfiles = MediaProfiles::getInstance();
 
     mOutputFd = -1;
@@ -831,7 +833,11 @@ status_t StagefrightRecorder::reset() {
 }
 
 status_t StagefrightRecorder::getMaxAmplitude(int *max) {
-    *max = 0;
+    if (mAudioSourceNode != 0) {
+        *max = mAudioSourceNode->getMaxAmplitude();
+    } else {
+        *max = 0;
+    }
 
     return OK;
 }

media/libmediaplayerservice/StagefrightRecorder.h

@@ -26,6 +26,7 @@ namespace android {
 class Camera;
 struct MediaSource;
 struct MediaWriter;
+struct AudioSource;
 class MediaProfiles;
 
 struct StagefrightRecorder : public MediaRecorderBase {
@@ -64,6 +65,7 @@ private:
     sp<ISurface> mPreviewSurface;
     sp<IMediaPlayerClient> mListener;
     sp<MediaWriter> mWriter;
+    sp<AudioSource> mAudioSourceNode;
 
     audio_source mAudioSource;
     video_source mVideoSource;

media/libstagefright/AudioSource.cpp

@@ -78,6 +78,8 @@ status_t AudioSource::start(MetaData *params) {
         mCollectStats = true;
     }
 
+    mTrackMaxAmplitude = false;
+    mMaxAmplitude = 0;
     mStartTimeUs = 0;
     int64_t startTimeUs;
     if (params && params->findInt64(kKeyTime, &startTimeUs)) {
@@ -168,6 +170,10 @@ status_t AudioSource::read(
         return (status_t)n;
     }
 
+    if (mTrackMaxAmplitude) {
+        trackMaxAmplitude((int16_t *) buffer->data(), n >> 1);
+    }
+
     uint32_t sampleRate = mRecord->getSampleRate();
     int64_t timestampUs = (1000000LL * numFramesRecorded) / sampleRate + mStartTimeUs;
     buffer->meta_data()->setInt64(kKeyTime, timestampUs);
@@ -181,4 +187,27 @@ status_t AudioSource::read(
     return OK;
 }
 
+void AudioSource::trackMaxAmplitude(int16_t *data, int nSamples) {
+    for (int i = nSamples; i > 0; --i) {
+        int16_t value = *data++;
+        if (value < 0) {
+            value = -value;
+        }
+        if (mMaxAmplitude < value) {
+            mMaxAmplitude = value;
+        }
+    }
+}
+
+int16_t AudioSource::getMaxAmplitude() {
+    // First call activates the tracking.
+    if (!mTrackMaxAmplitude) {
+        mTrackMaxAmplitude = true;
+    }
+    int16_t value = mMaxAmplitude;
+    mMaxAmplitude = 0;
+    LOGV("max amplitude since last call: %d", value);
+    return value;
+}
+
 }  // namespace android