aacenc: handle and warn overlapping timestamps

Bug: 143676467
Test: bug repro steps
Test: atest CtsMediaTestCases -- --module-arg CtsMediaTestCases:size:small
Change-Id: I09c679330e6c3fdf7329a1723b5e31cbd1c7e65b
diff --git a/media/codec2/components/aac/C2SoftAacEnc.cpp b/media/codec2/components/aac/C2SoftAacEnc.cpp
index be52a1d..4db94f5 100644
--- a/media/codec2/components/aac/C2SoftAacEnc.cpp
+++ b/media/codec2/components/aac/C2SoftAacEnc.cpp
@@ -155,9 +155,7 @@
       mNumBytesPerInputFrame(0u),
       mOutBufferSize(0u),
       mSentCodecSpecificData(false),
-      mInputTimeSet(false),
       mInputSize(0),
-      mNextFrameTimestampUs(0),
       mSignalledError(false),
       mOutIndex(0u),
       mRemainderLen(0u) {
@@ -182,9 +180,9 @@
 
 c2_status_t C2SoftAacEnc::onStop() {
     mSentCodecSpecificData = false;
-    mInputTimeSet = false;
     mInputSize = 0u;
-    mNextFrameTimestampUs = 0;
+    mNextFrameTimestampUs.reset();
+    mLastFrameEndTimestampUs.reset();
     mSignalledError = false;
     mRemainderLen = 0;
     return C2_OK;
@@ -201,9 +199,9 @@
 
 c2_status_t C2SoftAacEnc::onFlush_sm() {
     mSentCodecSpecificData = false;
-    mInputTimeSet = false;
     mInputSize = 0u;
-    mNextFrameTimestampUs = 0;
+    mNextFrameTimestampUs.reset();
+    mLastFrameEndTimestampUs.reset();
     return C2_OK;
 }
 
@@ -366,9 +364,19 @@
         data = view.data();
         capacity = view.capacity();
     }
-    if (!mInputTimeSet && capacity > 0) {
-        mNextFrameTimestampUs = work->input.ordinal.timestamp;
-        mInputTimeSet = true;
+    c2_cntr64_t inputTimestampUs = work->input.ordinal.timestamp;
+    if (inputTimestampUs < mLastFrameEndTimestampUs.value_or(inputTimestampUs)) {
+        ALOGW("Correcting overlapping timestamp: last frame ended at %lldus but "
+              "current frame is starting at %lldus. Using the last frame's end timestamp",
+              mLastFrameEndTimestampUs->peekll(), inputTimestampUs.peekll());
+        inputTimestampUs = *mLastFrameEndTimestampUs;
+    }
+    if (capacity > 0) {
+        if (!mNextFrameTimestampUs) {
+            mNextFrameTimestampUs = work->input.ordinal.timestamp;
+        }
+        mLastFrameEndTimestampUs = inputTimestampUs
+                + (capacity / sizeof(int16_t) * 1000000ll / channelCount / sampleRate);
     }
 
     size_t numFrames =
@@ -376,8 +384,7 @@
         / mNumBytesPerInputFrame;
     ALOGV("capacity = %zu; mInputSize = %zu; numFrames = %zu "
           "mNumBytesPerInputFrame = %u inputTS = %lld remaining = %zu",
-          capacity, mInputSize, numFrames,
-          mNumBytesPerInputFrame, work->input.ordinal.timestamp.peekll(),
+          capacity, mInputSize, numFrames, mNumBytesPerInputFrame, inputTimestampUs.peekll(),
           mRemainderLen);
 
     std::shared_ptr<C2LinearBlock> block;
@@ -505,8 +512,10 @@
                 mInputSize = 0;
                 int consumed = (capacity / sizeof(int16_t)) - inargs.numInSamples
                         + outargs.numInSamples;
-                c2_cntr64_t currentFrameTimestampUs = mNextFrameTimestampUs;
-                mNextFrameTimestampUs = work->input.ordinal.timestamp
+                ALOGV("consumed = %d, capacity = %zu, inSamples = %d, outSamples = %d",
+                      consumed, capacity, inargs.numInSamples, outargs.numInSamples);
+                c2_cntr64_t currentFrameTimestampUs = *mNextFrameTimestampUs;
+                mNextFrameTimestampUs = inputTimestampUs
                         + (consumed * 1000000ll / channelCount / sampleRate);
                 std::shared_ptr<C2Buffer> buffer = createLinearBuffer(block, 0, outargs.numOutBytes);
 #if 0
@@ -533,7 +542,7 @@
         }
         ALOGV("encoderErr = %d mInputSize = %zu "
               "inargs.numInSamples = %d, mNextFrameTimestampUs = %lld",
-              encoderErr, mInputSize, inargs.numInSamples, mNextFrameTimestampUs.peekll());
+              encoderErr, mInputSize, inargs.numInSamples, mNextFrameTimestampUs->peekll());
     }
     if (eos && inBufferSize[0] > 0) {
         if (numFrames && !block) {
@@ -617,9 +626,9 @@
 
     (void)pool;
     mSentCodecSpecificData = false;
-    mInputTimeSet = false;
     mInputSize = 0u;
-    mNextFrameTimestampUs = 0;
+    mNextFrameTimestampUs.reset();
+    mLastFrameEndTimestampUs.reset();
 
     // TODO: we don't have any pending work at this time to drain.
     return C2_OK;