Fix MediaCodec.flush()

There were two problems here. One was that the skip/cut buffer
wasn't cleared when it should be, and the second was that we
were always sending the first buffer of encoded data to the AAC
decoder twice.
b/8543366

Change-Id: Ic040edabf16cccd1f6ef8c9e5c9cfbacbdd8a089

1 files changed, 49 insertions, 54 deletions

diff --git a/media/libstagefright/codecs/aacdec/SoftAAC2.cpp b/media/libstagefright/codecs/aacdec/SoftAAC2.cpp
index a8ab2ac..8ba2afb 100644
--- a/media/libstagefright/codecs/aacdec/SoftAAC2.cpp
+++ b/media/libstagefright/codecs/aacdec/SoftAAC2.cpp
@@ -118,7 +118,7 @@ status_t SoftAAC2::initDecoder() {
             status = OK;
         }
     }
-    mIsFirst = true;
+    mDecoderHasData = false;
 
     // for streams that contain metadata, use the mobile profile DRC settings unless overridden
     // by platform properties:
@@ -327,6 +327,7 @@ void SoftAAC2::onQueueFilled(OMX_U32 portIndex) {
             notify(OMX_EventError, OMX_ErrorUndefined, decoderErr, NULL);
             return;
         }
+
         inQueue.erase(inQueue.begin());
         info->mOwnedByUs = false;
         notifyEmptyBufferDone(header);
@@ -358,7 +359,7 @@ void SoftAAC2::onQueueFilled(OMX_U32 portIndex) {
             inInfo->mOwnedByUs = false;
             notifyEmptyBufferDone(inHeader);
 
-            if (!mIsFirst) {
+            if (mDecoderHasData) {
                 // flush out the decoder's delayed data by calling DecodeFrame
                 // one more time, with the AACDEC_FLUSH flag set
                 INT_PCM *outBuffer =
@@ -370,6 +371,7 @@ void SoftAAC2::onQueueFilled(OMX_U32 portIndex) {
                                            outBuffer,
                                            outHeader->nAllocLen,
                                            AACDEC_FLUSH);
+                mDecoderHasData = false;
 
                 if (decoderErr != AAC_DEC_OK) {
                     mSignalledError = true;
@@ -385,9 +387,7 @@ void SoftAAC2::onQueueFilled(OMX_U32 portIndex) {
                             * sizeof(int16_t)
                             * mStreamInfo->numChannels;
             } else {
-                // Since we never discarded frames from the start, we won't have
-                // to add any padding at the end either.
-
+                // we never submitted any data to the decoder, so there's nothing to flush out
                 outHeader->nFilledLen = 0;
             }
 
@@ -473,6 +473,7 @@ void SoftAAC2::onQueueFilled(OMX_U32 portIndex) {
                             inBuffer,
                             inBufferLength,
                             bytesValid);
+            mDecoderHasData = true;
 
             decoderErr = aacDecoder_DecodeFrame(mAACDecoder,
                                                 outBuffer,
@@ -484,6 +485,35 @@ void SoftAAC2::onQueueFilled(OMX_U32 portIndex) {
             }
         }
 
+        size_t numOutBytes =
+            mStreamInfo->frameSize * sizeof(int16_t) * mStreamInfo->numChannels;
+
+        if (decoderErr == AAC_DEC_OK) {
+            UINT inBufferUsedLength = inBufferLength[0] - bytesValid[0];
+            inHeader->nFilledLen -= inBufferUsedLength;
+            inHeader->nOffset += inBufferUsedLength;
+        } else {
+            ALOGW("AAC decoder returned error %d, substituting silence",
+                  decoderErr);
+
+            memset(outHeader->pBuffer + outHeader->nOffset, 0, numOutBytes);
+
+            // Discard input buffer.
+            inHeader->nFilledLen = 0;
+
+            aacDecoder_SetParam(mAACDecoder, AAC_TPDEC_CLEAR_BUFFER, 1);
+
+            // fall through
+        }
+
+        if (inHeader->nFilledLen == 0) {
+            inInfo->mOwnedByUs = false;
+            inQueue.erase(inQueue.begin());
+            inInfo = NULL;
+            notifyEmptyBufferDone(inHeader);
+            inHeader = NULL;
+        }
+
         /*
          * AAC+/eAAC+ streams can be signalled in two ways: either explicitly
          * or implicitly, according to MPEG4 spec. AAC+/eAAC+ is a dual
@@ -502,15 +532,9 @@ void SoftAAC2::onQueueFilled(OMX_U32 portIndex) {
             if (mStreamInfo->sampleRate != prevSampleRate ||
                 mStreamInfo->numChannels != prevNumChannels) {
                 maybeConfigureDownmix();
-                ALOGI("Reconfiguring decoder: %d Hz, %d channels",
-                      mStreamInfo->sampleRate,
-                      mStreamInfo->numChannels);
-
-                // We're going to want to revisit this input buffer, but
-                // may have already advanced the offset. Undo that if
-                // necessary.
-                inHeader->nOffset -= adtsHeaderSize;
-                inHeader->nFilledLen += adtsHeaderSize;
+                ALOGI("Reconfiguring decoder: %d->%d Hz, %d->%d channels",
+                      prevSampleRate, mStreamInfo->sampleRate,
+                      prevNumChannels, mStreamInfo->numChannels);
 
                 notify(OMX_EventPortSettingsChanged, 1, 0, NULL);
                 mOutputPortSettingsChange = AWAITING_DISABLED;
@@ -523,38 +547,10 @@ void SoftAAC2::onQueueFilled(OMX_U32 portIndex) {
             return;
         }
 
-        size_t numOutBytes =
-            mStreamInfo->frameSize * sizeof(int16_t) * mStreamInfo->numChannels;
-
-        if (decoderErr == AAC_DEC_OK) {
-            UINT inBufferUsedLength = inBufferLength[0] - bytesValid[0];
-            inHeader->nFilledLen -= inBufferUsedLength;
-            inHeader->nOffset += inBufferUsedLength;
-        } else {
-            ALOGW("AAC decoder returned error %d, substituting silence",
-                  decoderErr);
-
-            memset(outHeader->pBuffer + outHeader->nOffset, 0, numOutBytes);
-
-            // Discard input buffer.
-            inHeader->nFilledLen = 0;
-
-            aacDecoder_SetParam(mAACDecoder, AAC_TPDEC_CLEAR_BUFFER, 1);
-
-            // fall through
-        }
-
         if (decoderErr == AAC_DEC_OK || mNumSamplesOutput > 0) {
             // We'll only output data if we successfully decoded it or
             // we've previously decoded valid data, in the latter case
             // (decode failed) we'll output a silent frame.
-            if (mIsFirst) {
-                mIsFirst = false;
-                // the first decoded frame should be discarded to account
-                // for decoder delay
-                numOutBytes = 0;
-            }
-
             outHeader->nFilledLen = numOutBytes;
             outHeader->nFlags = 0;
 
@@ -571,14 +567,6 @@ void SoftAAC2::onQueueFilled(OMX_U32 portIndex) {
             outHeader = NULL;
         }
 
-        if (inHeader->nFilledLen == 0) {
-            inInfo->mOwnedByUs = false;
-            inQueue.erase(inQueue.begin());
-            inInfo = NULL;
-            notifyEmptyBufferDone(inHeader);
-            inHeader = NULL;
-        }
-
         if (decoderErr == AAC_DEC_OK) {
             ++mInputBufferCount;
         }
@@ -589,14 +577,21 @@ void SoftAAC2::onPortFlushCompleted(OMX_U32 portIndex) {
     if (portIndex == 0) {
         // Make sure that the next buffer output does not still
         // depend on fragments from the last one decoded.
-        aacDecoder_SetParam(mAACDecoder, AAC_TPDEC_CLEAR_BUFFER, 1);
-        mIsFirst = true;
+        // drain all existing data
+        drainDecoder();
     }
 }
 
-void SoftAAC2::onReset() {
+void SoftAAC2::drainDecoder() {
+    short buf [2048];
+    aacDecoder_DecodeFrame(mAACDecoder, buf, 4096, AACDEC_FLUSH | AACDEC_CLRHIST | AACDEC_INTR);
+    aacDecoder_DecodeFrame(mAACDecoder, buf, 4096, AACDEC_FLUSH | AACDEC_CLRHIST | AACDEC_INTR);
     aacDecoder_SetParam(mAACDecoder, AAC_TPDEC_CLEAR_BUFFER, 1);
-    mIsFirst = true;
+    mDecoderHasData = false;
+}
+
+void SoftAAC2::onReset() {
+    drainDecoder();
 }
 
 void SoftAAC2::onPortEnableCompleted(OMX_U32 portIndex, bool enabled) {