OMX IL wrapper for FLAC encoder

Add wrapper around libFLAC for FLAC encoding in OpenMAX IL.

Declare FLAC encoder in OMX component roles.

Bug 5525503

Change-Id: I19bbce41c216870669d09365693f4ea89f8bc0f7

8 files changed, 631 insertions, 1 deletions

diff --git a/include/media/stagefright/ACodec.h b/include/media/stagefright/ACodec.h
index 7536d10..dd18e95 100644
--- a/include/media/stagefright/ACodec.h
+++ b/include/media/stagefright/ACodec.h
@@ -198,6 +198,9 @@ private:
     status_t setupAMRCodec(bool encoder, bool isWAMR, int32_t bitRate);
     status_t setupG711Codec(bool encoder, int32_t numChannels);
 
+    status_t setupFlacCodec(
+            bool encoder, int32_t numChannels, int32_t sampleRate, int32_t compressionLevel);
+
     status_t setupRawAudioFormat(
             OMX_U32 portIndex, int32_t sampleRate, int32_t numChannels);
 
diff --git a/media/libstagefright/ACodec.cpp b/media/libstagefright/ACodec.cpp
index 1e00c5d..3fd6cef 100644
--- a/media/libstagefright/ACodec.cpp
+++ b/media/libstagefright/ACodec.cpp
@@ -774,6 +774,8 @@ status_t ACodec::setComponentRole(
             "video_decoder.vpx", "video_encoder.vpx" },
         { MEDIA_MIMETYPE_AUDIO_RAW,
             "audio_decoder.raw", "audio_encoder.raw" },
+        { MEDIA_MIMETYPE_AUDIO_FLAC,
+            "audio_decoder.flac", "audio_encoder.flac" },
     };
 
     static const size_t kNumMimeToRole =
@@ -834,7 +836,9 @@ status_t ACodec::configureCodec(
     }
 
     int32_t bitRate = 0;
-    if (encoder && !msg->findInt32("bitrate", &bitRate)) {
+    // FLAC encoder doesn't need a bitrate, other encoders do
+    if (encoder && strcasecmp(mime, MEDIA_MIMETYPE_AUDIO_FLAC)
+            && !msg->findInt32("bitrate", &bitRate)) {
         return INVALID_OPERATION;
     }
 
@@ -882,6 +886,27 @@ status_t ACodec::configureCodec(
         } else {
             err = setupG711Codec(encoder, numChannels);
         }
+    } else if (!strcasecmp(mime, MEDIA_MIMETYPE_AUDIO_FLAC)) {
+        int32_t numChannels, sampleRate, compressionLevel = -1;
+        if (encoder &&
+                (!msg->findInt32("channel-count", &numChannels)
+                        || !msg->findInt32("sample-rate", &sampleRate))) {
+            ALOGE("missing channel count or sample rate for FLAC encoder");
+            err = INVALID_OPERATION;
+        } else {
+            if (encoder) {
+                if (!msg->findInt32("flac-compression-level", &compressionLevel)) {
+                    compressionLevel = 5;// default FLAC compression level
+                } else if (compressionLevel < 0) {
+                    ALOGW("compression level %d outside [0..8] range, using 0", compressionLevel);
+                    compressionLevel = 0;
+                } else if (compressionLevel > 8) {
+                    ALOGW("compression level %d outside [0..8] range, using 8", compressionLevel);
+                    compressionLevel = 8;
+                }
+            }
+            err = setupFlacCodec(encoder, numChannels, sampleRate, compressionLevel);
+        }
     } else if (!strcasecmp(mime, MEDIA_MIMETYPE_AUDIO_RAW)) {
         int32_t numChannels, sampleRate;
         if (encoder
@@ -1163,6 +1188,34 @@ status_t ACodec::setupG711Codec(bool encoder, int32_t numChannels) {
             kPortIndexInput, 8000 /* sampleRate */, numChannels);
 }
 
+status_t ACodec::setupFlacCodec(
+        bool encoder, int32_t numChannels, int32_t sampleRate, int32_t compressionLevel) {
+
+    if (encoder) {
+        OMX_AUDIO_PARAM_FLACTYPE def;
+        InitOMXParams(&def);
+        def.nPortIndex = kPortIndexOutput;
+
+        // configure compression level
+        status_t err = mOMX->getParameter(mNode, OMX_IndexParamAudioFlac, &def, sizeof(def));
+        if (err != OK) {
+            ALOGE("setupFlacCodec(): Error %d getting OMX_IndexParamAudioFlac parameter", err);
+            return err;
+        }
+        def.nCompressionLevel = compressionLevel;
+        err = mOMX->setParameter(mNode, OMX_IndexParamAudioFlac, &def, sizeof(def));
+        if (err != OK) {
+            ALOGE("setupFlacCodec(): Error %d setting OMX_IndexParamAudioFlac parameter", err);
+            return err;
+        }
+    }
+
+    return setupRawAudioFormat(
+            encoder ? kPortIndexInput : kPortIndexOutput,
+            sampleRate,
+            numChannels);
+}
+
 status_t ACodec::setupRawAudioFormat(
         OMX_U32 portIndex, int32_t sampleRate, int32_t numChannels) {
     OMX_PARAM_PORTDEFINITIONTYPE def;
diff --git a/media/libstagefright/OMXCodec.cpp b/media/libstagefright/OMXCodec.cpp
index 604d0e0..6083cd4 100755
--- a/media/libstagefright/OMXCodec.cpp
+++ b/media/libstagefright/OMXCodec.cpp
@@ -1364,6 +1364,8 @@ void OMXCodec::setComponentRole(
             "video_decoder.vpx", "video_encoder.vpx" },
         { MEDIA_MIMETYPE_AUDIO_RAW,
             "audio_decoder.raw", "audio_encoder.raw" },
+        { MEDIA_MIMETYPE_AUDIO_FLAC,
+            "audio_decoder.flac", "audio_encoder.flac" },
     };
 
     static const size_t kNumMimeToRole =
diff --git a/media/libstagefright/codecs/flac/Android.mk b/media/libstagefright/codecs/flac/Android.mk
new file mode 100644
index 0000000..2e43120
--- /dev/null
+++ b/media/libstagefright/codecs/flac/Android.mk
@@ -0,0 +1,4 @@
+LOCAL_PATH:= $(call my-dir)
+include $(CLEAR_VARS)
+
+include $(call all-makefiles-under,$(LOCAL_PATH))
diff --git a/media/libstagefright/codecs/flac/enc/Android.mk b/media/libstagefright/codecs/flac/enc/Android.mk
new file mode 100644
index 0000000..546a357
--- /dev/null
+++ b/media/libstagefright/codecs/flac/enc/Android.mk
@@ -0,0 +1,21 @@
+LOCAL_PATH:= $(call my-dir)
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES := \
+        SoftFlacEncoder.cpp
+
+LOCAL_C_INCLUDES := \
+        frameworks/av/media/libstagefright/include \
+        frameworks/native/include/media/openmax \
+        external/flac/include
+
+LOCAL_SHARED_LIBRARIES := \
+        libstagefright libstagefright_omx libstagefright_foundation libutils
+
+LOCAL_STATIC_LIBRARIES := \
+        libFLAC \
+
+LOCAL_MODULE := libstagefright_soft_flacenc
+LOCAL_MODULE_TAGS := optional
+
+include $(BUILD_SHARED_LIBRARY)
diff --git a/media/libstagefright/codecs/flac/enc/SoftFlacEncoder.cpp b/media/libstagefright/codecs/flac/enc/SoftFlacEncoder.cpp
new file mode 100644
index 0000000..233aed3
--- /dev/null
+++ b/media/libstagefright/codecs/flac/enc/SoftFlacEncoder.cpp
@@ -0,0 +1,444 @@
+/*
+ * Copyright (C) 2012 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.
+ */
+
+//#define LOG_NDEBUG 0
+#define LOG_TAG "SoftFlacEncoder"
+#include <utils/Log.h>
+
+#include "SoftFlacEncoder.h"
+
+#include <media/stagefright/foundation/ADebug.h>
+#include <media/stagefright/MediaDefs.h>
+
+#define FLAC_COMPRESSION_LEVEL_MIN     0
+#define FLAC_COMPRESSION_LEVEL_DEFAULT 5
+#define FLAC_COMPRESSION_LEVEL_MAX     8
+
+namespace android {
+
+template<class T>
+static void InitOMXParams(T *params) {
+    params->nSize = sizeof(T);
+    params->nVersion.s.nVersionMajor = 1;
+    params->nVersion.s.nVersionMinor = 0;
+    params->nVersion.s.nRevision = 0;
+    params->nVersion.s.nStep = 0;
+}
+
+SoftFlacEncoder::SoftFlacEncoder(
+        const char *name,
+        const OMX_CALLBACKTYPE *callbacks,
+        OMX_PTR appData,
+        OMX_COMPONENTTYPE **component)
+    : SimpleSoftOMXComponent(name, callbacks, appData, component),
+      mSignalledError(false),
+      mNumChannels(1),
+      mSampleRate(44100),
+      mCompressionLevel(FLAC_COMPRESSION_LEVEL_DEFAULT),
+      mEncoderWriteData(false),
+      mEncoderReturnedEncodedData(false),
+      mEncoderReturnedNbBytes(0),
+      mInputBufferPcm32(NULL)
+#ifdef WRITE_FLAC_HEADER_IN_FIRST_BUFFER
+      , mHeaderOffset(0)
+      , mWroteHeader(false)
+#endif
+{
+    ALOGV("SoftFlacEncoder::SoftFlacEncoder(name=%s)", name);
+    initPorts();
+
+    mFlacStreamEncoder = FLAC__stream_encoder_new();
+    if (mFlacStreamEncoder == NULL) {
+        ALOGE("SoftFlacEncoder::SoftFlacEncoder(name=%s) error instantiating FLAC encoder", name);
+        mSignalledError = true;
+    }
+
+    if (!mSignalledError) { // no use allocating input buffer if we had an error above
+        mInputBufferPcm32 = (FLAC__int32*) malloc(sizeof(FLAC__int32) * 2 * kMaxNumSamplesPerFrame);
+        if (mInputBufferPcm32 == NULL) {
+            ALOGE("SoftFlacEncoder::SoftFlacEncoder(name=%s) error allocating internal input buffer", name);
+            mSignalledError = true;
+        }
+    }
+}
+
+SoftFlacEncoder::~SoftFlacEncoder() {
+    ALOGV("SoftFlacEncoder::~SoftFlacEncoder()");
+    if (mFlacStreamEncoder != NULL) {
+        FLAC__stream_encoder_delete(mFlacStreamEncoder);
+        mFlacStreamEncoder = NULL;
+    }
+    free(mInputBufferPcm32);
+    mInputBufferPcm32 = NULL;
+}
+
+OMX_ERRORTYPE SoftFlacEncoder::initCheck() const {
+    if (mSignalledError) {
+        if (mFlacStreamEncoder == NULL) {
+            ALOGE("initCheck() failed due to NULL encoder");
+        } else if (mInputBufferPcm32 == NULL) {
+            ALOGE("initCheck() failed due to error allocating internal input buffer");
+        }
+        return OMX_ErrorUndefined;
+    } else {
+        return SimpleSoftOMXComponent::initCheck();
+    }
+}
+
+void SoftFlacEncoder::initPorts() {
+    ALOGV("SoftFlacEncoder::initPorts()");
+
+    OMX_PARAM_PORTDEFINITIONTYPE def;
+    InitOMXParams(&def);
+
+    // configure input port of the encoder
+    def.nPortIndex = 0;
+    def.eDir = OMX_DirInput;
+    def.nBufferCountMin = kNumBuffers;// TODO verify that 1 is enough
+    def.nBufferCountActual = def.nBufferCountMin;
+    def.nBufferSize = kMaxNumSamplesPerFrame * sizeof(int16_t) * 2;
+    def.bEnabled = OMX_TRUE;
+    def.bPopulated = OMX_FALSE;
+    def.eDomain = OMX_PortDomainAudio;
+    def.bBuffersContiguous = OMX_FALSE;
+    def.nBufferAlignment = 2;
+
+    def.format.audio.cMIMEType = const_cast<char *>("audio/raw");
+    def.format.audio.pNativeRender = NULL;
+    def.format.audio.bFlagErrorConcealment = OMX_FALSE;
+    def.format.audio.eEncoding = OMX_AUDIO_CodingPCM;
+
+    addPort(def);
+
+    // configure output port of the encoder
+    def.nPortIndex = 1;
+    def.eDir = OMX_DirOutput;
+    def.nBufferCountMin = kNumBuffers;// TODO verify that 1 is enough
+    def.nBufferCountActual = def.nBufferCountMin;
+    def.nBufferSize = kMaxOutputBufferSize;
+    def.bEnabled = OMX_TRUE;
+    def.bPopulated = OMX_FALSE;
+    def.eDomain = OMX_PortDomainAudio;
+    def.bBuffersContiguous = OMX_FALSE;
+    def.nBufferAlignment = 1;
+
+    def.format.audio.cMIMEType = const_cast<char *>(MEDIA_MIMETYPE_AUDIO_FLAC);
+    def.format.audio.pNativeRender = NULL;
+    def.format.audio.bFlagErrorConcealment = OMX_FALSE;
+    def.format.audio.eEncoding = OMX_AUDIO_CodingFLAC;
+
+    addPort(def);
+}
+
+OMX_ERRORTYPE SoftFlacEncoder::internalGetParameter(
+        OMX_INDEXTYPE index, OMX_PTR params) {
+    ALOGV("SoftFlacEncoder::internalGetParameter(index=0x%x)", index);
+
+    switch (index) {
+        case OMX_IndexParamAudioPcm:
+        {
+            OMX_AUDIO_PARAM_PCMMODETYPE *pcmParams =
+                (OMX_AUDIO_PARAM_PCMMODETYPE *)params;
+
+            if (pcmParams->nPortIndex > 1) {
+                return OMX_ErrorUndefined;
+            }
+
+            pcmParams->eNumData = OMX_NumericalDataSigned;
+            pcmParams->eEndian = OMX_EndianBig;
+            pcmParams->bInterleaved = OMX_TRUE;
+            pcmParams->nBitPerSample = 16;
+            pcmParams->ePCMMode = OMX_AUDIO_PCMModeLinear;
+            pcmParams->eChannelMapping[0] = OMX_AUDIO_ChannelLF;
+            pcmParams->eChannelMapping[1] = OMX_AUDIO_ChannelRF;
+
+            pcmParams->nChannels = mNumChannels;
+            pcmParams->nSamplingRate = mSampleRate;
+
+            return OMX_ErrorNone;
+        }
+
+        case OMX_IndexParamAudioFlac:
+        {
+            OMX_AUDIO_PARAM_FLACTYPE *flacParams = (OMX_AUDIO_PARAM_FLACTYPE *)params;
+            flacParams->nCompressionLevel = mCompressionLevel;
+            flacParams->nChannels = mNumChannels;
+            flacParams->nSampleRate = mSampleRate;
+            return OMX_ErrorNone;
+        }
+
+        default:
+            return SimpleSoftOMXComponent::internalGetParameter(index, params);
+    }
+}
+
+OMX_ERRORTYPE SoftFlacEncoder::internalSetParameter(
+        OMX_INDEXTYPE index, const OMX_PTR params) {
+    switch (index) {
+        case OMX_IndexParamAudioPcm:
+        {
+            ALOGV("SoftFlacEncoder::internalSetParameter(OMX_IndexParamAudioPcm)");
+            OMX_AUDIO_PARAM_PCMMODETYPE *pcmParams = (OMX_AUDIO_PARAM_PCMMODETYPE *)params;
+
+            if (pcmParams->nPortIndex != 0 && pcmParams->nPortIndex != 1) {
+                ALOGE("SoftFlacEncoder::internalSetParameter() Error #1");
+                return OMX_ErrorUndefined;
+            }
+
+            if (pcmParams->nChannels < 1 || pcmParams->nChannels > 2) {
+                return OMX_ErrorUndefined;
+            }
+
+            mNumChannels = pcmParams->nChannels;
+            mSampleRate = pcmParams->nSamplingRate;
+            ALOGV("will encode %ld channels at %ldHz", mNumChannels, mSampleRate);
+
+            return configureEncoder();
+        }
+
+        case OMX_IndexParamStandardComponentRole:
+        {
+            ALOGV("SoftFlacEncoder::internalSetParameter(OMX_IndexParamStandardComponentRole)");
+            const OMX_PARAM_COMPONENTROLETYPE *roleParams =
+                (const OMX_PARAM_COMPONENTROLETYPE *)params;
+
+            if (strncmp((const char *)roleParams->cRole,
+                    "audio_encoder.flac",
+                    OMX_MAX_STRINGNAME_SIZE - 1)) {
+                ALOGE("SoftFlacEncoder::internalSetParameter(OMX_IndexParamStandardComponentRole)"
+                        "error");
+                return OMX_ErrorUndefined;
+            }
+
+            return OMX_ErrorNone;
+        }
+
+        case OMX_IndexParamAudioFlac:
+        {
+            // used only for setting the compression level
+            OMX_AUDIO_PARAM_FLACTYPE *flacParams = (OMX_AUDIO_PARAM_FLACTYPE *)params;
+            mCompressionLevel = flacParams->nCompressionLevel; // range clamping done inside encoder
+            return OMX_ErrorNone;
+        }
+
+        default:
+            ALOGV("SoftFlacEncoder::internalSetParameter(default)");
+            return SimpleSoftOMXComponent::internalSetParameter(index, params);
+    }
+}
+
+void SoftFlacEncoder::onQueueFilled(OMX_U32 portIndex) {
+
+    ALOGV("SoftFlacEncoder::onQueueFilled(portIndex=%ld)", portIndex);
+
+    if (mSignalledError) {
+        return;
+    }
+
+    List<BufferInfo *> &inQueue = getPortQueue(0);
+    List<BufferInfo *> &outQueue = getPortQueue(1);
+
+    while (!inQueue.empty() && !outQueue.empty()) {
+        BufferInfo *inInfo = *inQueue.begin();
+        OMX_BUFFERHEADERTYPE *inHeader = inInfo->mHeader;
+
+        BufferInfo *outInfo = *outQueue.begin();
+        OMX_BUFFERHEADERTYPE *outHeader = outInfo->mHeader;
+
+        if (inHeader->nFlags & OMX_BUFFERFLAG_EOS) {
+            inQueue.erase(inQueue.begin());
+            inInfo->mOwnedByUs = false;
+            notifyEmptyBufferDone(inHeader);
+
+            outHeader->nFilledLen = 0;
+            outHeader->nFlags = OMX_BUFFERFLAG_EOS;
+
+            outQueue.erase(outQueue.begin());
+            outInfo->mOwnedByUs = false;
+            notifyFillBufferDone(outHeader);
+
+            return;
+        }
+
+        if (inHeader->nFilledLen > kMaxNumSamplesPerFrame * sizeof(FLAC__int32) * 2) {
+            ALOGE("input buffer too large (%ld).", inHeader->nFilledLen);
+            mSignalledError = true;
+            notify(OMX_EventError, OMX_ErrorUndefined, 0, NULL);
+            return;
+        }
+
+        assert(mNumChannels != 0);
+        mEncoderWriteData = true;
+        mEncoderReturnedEncodedData = false;
+        mEncoderReturnedNbBytes = 0;
+        mCurrentInputTimeStamp = inHeader->nTimeStamp;
+
+        const unsigned nbInputFrames = inHeader->nFilledLen / (2 * mNumChannels);
+        const unsigned nbInputSamples = inHeader->nFilledLen / 2;
+        const OMX_S16 * const pcm16 = reinterpret_cast<OMX_S16 *>(inHeader->pBuffer);
+
+        for (unsigned i=0 ; i < nbInputSamples ; i++) {
+            mInputBufferPcm32[i] = (FLAC__int32) pcm16[i];
+        }
+        ALOGV(" about to encode %u samples per channel", nbInputFrames);
+        FLAC__bool ok = FLAC__stream_encoder_process_interleaved(
+                        mFlacStreamEncoder,
+                        mInputBufferPcm32,
+                        nbInputFrames /*samples per channel*/ );
+
+        if (ok) {
+            if (mEncoderReturnedEncodedData && (mEncoderReturnedNbBytes != 0)) {
+                ALOGV(" dequeueing buffer on output port after writing data");
+                outInfo->mOwnedByUs = false;
+                outQueue.erase(outQueue.begin());
+                outInfo = NULL;
+                notifyFillBufferDone(outHeader);
+                outHeader = NULL;
+                mEncoderReturnedEncodedData = false;
+            } else {
+                ALOGV(" encoder process_interleaved returned without data to write");
+            }
+        } else {
+            ALOGE(" error encountered during encoding");
+            mSignalledError = true;
+            notify(OMX_EventError, OMX_ErrorUndefined, 0, NULL);
+            return;
+        }
+
+        inInfo->mOwnedByUs = false;
+        inQueue.erase(inQueue.begin());
+        inInfo = NULL;
+        notifyEmptyBufferDone(inHeader);
+        inHeader = NULL;
+    }
+}
+
+
+FLAC__StreamEncoderWriteStatus SoftFlacEncoder::onEncodedFlacAvailable(
+            const FLAC__byte buffer[],
+            size_t bytes, unsigned samples, unsigned current_frame) {
+    ALOGV("SoftFlacEncoder::onEncodedFlacAvailable(bytes=%d, samples=%d, curr_frame=%d)",
+            bytes, samples, current_frame);
+
+#ifdef WRITE_FLAC_HEADER_IN_FIRST_BUFFER
+    if (samples == 0) {
+        ALOGI(" saving %d bytes of header", bytes);
+        memcpy(mHeader + mHeaderOffset, buffer, bytes);
+        mHeaderOffset += bytes;// will contain header size when finished receiving header
+        return FLAC__STREAM_ENCODER_WRITE_STATUS_OK;
+    }
+
+#endif
+
+    if ((samples == 0) || !mEncoderWriteData) {
+        // called by the encoder because there's header data to save, but it's not the role
+        // of this component (unless WRITE_FLAC_HEADER_IN_FIRST_BUFFER is defined)
+        ALOGV("ignoring %d bytes of header data (samples=%d)", bytes, samples);
+        return FLAC__STREAM_ENCODER_WRITE_STATUS_OK;
+    }
+
+    List<BufferInfo *> &outQueue = getPortQueue(1);
+    CHECK(!outQueue.empty());
+    BufferInfo *outInfo = *outQueue.begin();
+    OMX_BUFFERHEADERTYPE *outHeader = outInfo->mHeader;
+
+#ifdef WRITE_FLAC_HEADER_IN_FIRST_BUFFER
+    if (!mWroteHeader) {
+        ALOGI(" writing %d bytes of header on output port", mHeaderOffset);
+        memcpy(outHeader->pBuffer + outHeader->nOffset + outHeader->nFilledLen,
+                mHeader, mHeaderOffset);
+        outHeader->nFilledLen += mHeaderOffset;
+        outHeader->nOffset    += mHeaderOffset;
+        mWroteHeader = true;
+    }
+#endif
+
+    // write encoded data
+    ALOGV(" writing %d bytes of encoded data on output port", bytes);
+    if (bytes > outHeader->nAllocLen - outHeader->nOffset - outHeader->nFilledLen) {
+        ALOGE(" not enough space left to write encoded data, dropping %u bytes", bytes);
+        // a fatal error would stop the encoding
+        return FLAC__STREAM_ENCODER_WRITE_STATUS_OK;
+    }
+    memcpy(outHeader->pBuffer + outHeader->nOffset, buffer, bytes);
+
+    outHeader->nTimeStamp = mCurrentInputTimeStamp;
+    outHeader->nOffset = 0;
+    outHeader->nFilledLen += bytes;
+    outHeader->nFlags = 0;
+
+    mEncoderReturnedEncodedData = true;
+    mEncoderReturnedNbBytes += bytes;
+
+    return FLAC__STREAM_ENCODER_WRITE_STATUS_OK;
+}
+
+
+OMX_ERRORTYPE SoftFlacEncoder::configureEncoder() {
+    ALOGV("SoftFlacEncoder::configureEncoder() numChannel=%ld, sampleRate=%ld",
+            mNumChannels, mSampleRate);
+
+    if (mSignalledError || (mFlacStreamEncoder == NULL)) {
+        ALOGE("can't configure encoder: no encoder or invalid state");
+        return OMX_ErrorInvalidState;
+    }
+
+    FLAC__bool ok = true;
+    FLAC__StreamEncoderInitStatus initStatus = FLAC__STREAM_ENCODER_INIT_STATUS_OK;
+    ok = ok && FLAC__stream_encoder_set_channels(mFlacStreamEncoder, mNumChannels);
+    ok = ok && FLAC__stream_encoder_set_sample_rate(mFlacStreamEncoder, mSampleRate);
+    ok = ok && FLAC__stream_encoder_set_bits_per_sample(mFlacStreamEncoder, 16);
+    ok = ok && FLAC__stream_encoder_set_compression_level(mFlacStreamEncoder,
+            (unsigned)mCompressionLevel);
+    ok = ok && FLAC__stream_encoder_set_verify(mFlacStreamEncoder, false);
+    if (!ok) { goto return_result; }
+
+    ok &= FLAC__STREAM_ENCODER_INIT_STATUS_OK ==
+            FLAC__stream_encoder_init_stream(mFlacStreamEncoder,
+                    flacEncoderWriteCallback    /*write_callback*/,
+                    NULL /*seek_callback*/,
+                    NULL /*tell_callback*/,
+                    NULL /*metadata_callback*/,
+                    (void *) this /*client_data*/);
+
+return_result:
+    if (ok) {
+        ALOGV("encoder successfully configured");
+        return OMX_ErrorNone;
+    } else {
+        ALOGE("unknown error when configuring encoder");
+        return OMX_ErrorUndefined;
+    }
+}
+
+
+// static
+FLAC__StreamEncoderWriteStatus SoftFlacEncoder::flacEncoderWriteCallback(
+            const FLAC__StreamEncoder *encoder, const FLAC__byte buffer[],
+            size_t bytes, unsigned samples, unsigned current_frame, void *client_data) {
+    return ((SoftFlacEncoder*) client_data)->onEncodedFlacAvailable(
+            buffer, bytes, samples, current_frame);
+}
+
+}  // namespace android
+
+
+android::SoftOMXComponent *createSoftOMXComponent(
+        const char *name, const OMX_CALLBACKTYPE *callbacks,
+        OMX_PTR appData, OMX_COMPONENTTYPE **component) {
+    return new android::SoftFlacEncoder(name, callbacks, appData, component);
+}
+
diff --git a/media/libstagefright/codecs/flac/enc/SoftFlacEncoder.h b/media/libstagefright/codecs/flac/enc/SoftFlacEncoder.h
new file mode 100644
index 0000000..1e0148a
--- /dev/null
+++ b/media/libstagefright/codecs/flac/enc/SoftFlacEncoder.h
@@ -0,0 +1,102 @@
+/*
+ * Copyright (C) 2012 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.
+ */
+
+#ifndef SOFT_FLAC_ENC_H_
+
+#define SOFT_FLAC_ENC_H_
+
+#include "SimpleSoftOMXComponent.h"
+
+#include "FLAC/stream_encoder.h"
+
+// use this symbol to have the first output buffer start with FLAC frame header so a dump of
+// all the output buffers can be opened as a .flac file
+//#define WRITE_FLAC_HEADER_IN_FIRST_BUFFER
+
+namespace android {
+
+struct SoftFlacEncoder : public SimpleSoftOMXComponent {
+    SoftFlacEncoder(const char *name,
+            const OMX_CALLBACKTYPE *callbacks,
+            OMX_PTR appData,
+            OMX_COMPONENTTYPE **component);
+
+    virtual OMX_ERRORTYPE initCheck() const;
+
+protected:
+    virtual ~SoftFlacEncoder();
+
+    virtual OMX_ERRORTYPE internalGetParameter(
+            OMX_INDEXTYPE index, OMX_PTR params);
+
+    virtual OMX_ERRORTYPE internalSetParameter(
+            OMX_INDEXTYPE index, const OMX_PTR params);
+
+    virtual void onQueueFilled(OMX_U32 portIndex);
+
+private:
+
+    enum {
+        kNumBuffers = 2,
+        kMaxNumSamplesPerFrame = 1152,
+        kMaxOutputBufferSize = 65536,    //TODO check if this can be reduced
+    };
+
+    bool mSignalledError;
+
+    OMX_U32 mNumChannels;
+    OMX_U32 mSampleRate;
+    OMX_U32 mCompressionLevel;
+
+    // should the data received by the callback be written to the output port
+    bool        mEncoderWriteData;
+    bool        mEncoderReturnedEncodedData;
+    size_t      mEncoderReturnedNbBytes;
+    OMX_TICKS  mCurrentInputTimeStamp;
+
+    FLAC__StreamEncoder* mFlacStreamEncoder;
+
+    void initPorts();
+
+    OMX_ERRORTYPE configureEncoder();
+
+    // FLAC encoder callbacks
+    // maps to encoderEncodeFlac()
+    static FLAC__StreamEncoderWriteStatus flacEncoderWriteCallback(
+            const FLAC__StreamEncoder *encoder, const FLAC__byte buffer[],
+            size_t bytes, unsigned samples, unsigned current_frame, void *client_data);
+
+    FLAC__StreamEncoderWriteStatus onEncodedFlacAvailable(
+                const FLAC__byte buffer[],
+                size_t bytes, unsigned samples, unsigned current_frame);
+
+    // FLAC takes samples aligned on 32bit boundaries, use this buffer for the conversion
+    // before passing the input data to the encoder
+    FLAC__int32* mInputBufferPcm32;
+
+#ifdef WRITE_FLAC_HEADER_IN_FIRST_BUFFER
+    unsigned mHeaderOffset;
+    bool mWroteHeader;
+    char mHeader[128];
+#endif
+
+    DISALLOW_EVIL_CONSTRUCTORS(SoftFlacEncoder);
+};
+
+}  // namespace android
+
+#endif  // SOFT_FLAC_ENC_H_
+
diff --git a/media/libstagefright/omx/SoftOMXPlugin.cpp b/media/libstagefright/omx/SoftOMXPlugin.cpp
index 6e53095..3747b3b 100644
--- a/media/libstagefright/omx/SoftOMXPlugin.cpp
+++ b/media/libstagefright/omx/SoftOMXPlugin.cpp
@@ -52,6 +52,7 @@ static const struct {
     { "OMX.google.vorbis.decoder", "vorbisdec", "audio_decoder.vorbis" },
     { "OMX.google.vpx.decoder", "vpxdec", "video_decoder.vpx" },
     { "OMX.google.raw.decoder", "rawdec", "audio_decoder.raw" },
+    { "OMX.google.flac.encoder", "flacenc", "audio_encoder.flac" },
 };
 
 static const size_t kNumComponents =