MediaMuxer:SetCaptureRate for GCA SlowMotionRecord

MediaMuxer would find 'time-lapse-fps' value in input format from GCA
and pass it on to MPEG4Writer for SlowMotionRecord.

Bug: 138995916

Test: atest CtsMediaTestCases
      atest CtsMediaTestCases:android.media.cts.MediaMuxerTest

Change-Id: I6af102540ddd439b203351ebba07eabf89f2d330

media/libstagefright/MPEG4Writer.cpp

@@ -1635,8 +1635,13 @@ status_t MPEG4Writer::setCaptureRate(float captureFps) {
         return BAD_VALUE;
     }
 
+    // Increase moovExtraSize once only irrespective of how many times
+    // setCaptureRate is called.
+    bool containsCaptureFps = mMetaKeys->contains(kMetaKey_CaptureFps);
     mMetaKeys->setFloat(kMetaKey_CaptureFps, captureFps);
-    mMoovExtraSize += sizeof(kMetaKey_CaptureFps) + 4 + 32;
+    if (!containsCaptureFps) {
+        mMoovExtraSize += sizeof(kMetaKey_CaptureFps) + 4 + 32;
+    }
 
     return OK;
 }

media/libstagefright/MediaMuxer.cpp

@@ -96,10 +96,18 @@ ssize_t MediaMuxer::addTrack(const sp<AMessage> &format) {
 
     sp<MediaAdapter> newTrack = new MediaAdapter(trackMeta);
     status_t result = mWriter->addSource(newTrack);
-    if (result == OK) {
-        return mTrackList.add(newTrack);
+    if (result != OK) {
+        return -1;
+    }
+    float captureFps = -1.0;
+    if (format->findAsFloat("time-lapse-fps", &captureFps)) {
+        ALOGV("addTrack() time-lapse-fps: %f", captureFps);
+        result = mWriter->setCaptureRate(captureFps);
+        if (result != OK) {
+            ALOGW("addTrack() setCaptureRate failed :%d", result);
+        }
     }
-    return -1;
+    return mTrackList.add(newTrack);
 }
 
 status_t MediaMuxer::setOrientationHint(int degrees) {

media/libstagefright/include/media/stagefright/MediaWriter.h

@@ -35,6 +35,10 @@ struct MediaWriter : public RefBase {
     virtual status_t start(MetaData *params = NULL) = 0;
     virtual status_t stop() = 0;
     virtual status_t pause() = 0;
+    virtual status_t setCaptureRate(float /* captureFps */) {
+        ALOGW("setCaptureRate unsupported");
+        return ERROR_UNSUPPORTED;
+    }
 
     virtual void setMaxFileSize(int64_t bytes) { mMaxFileSizeLimitBytes = bytes; }
     virtual void setMaxFileDuration(int64_t durationUs) { mMaxFileDurationLimitUs = durationUs; }