Changed VP8 to follow the style guide a little bit more.

Review URL: https://webrtc-codereview.appspot.com/379003

git-svn-id: http://webrtc.googlecode.com/svn/trunk@1593 4adac7df-926f-26a2-2b94-8c16560cd09d
This commit is contained in:
pwestin@webrtc.org 2012-02-02 12:21:47 +00:00
parent 9b3474aff8
commit 4ea57e5e26
9 changed files with 1019 additions and 1241 deletions

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@ -1,5 +1,5 @@
/*
* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
* Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
@ -51,8 +51,8 @@ class VideoProcessorIntegrationTest: public testing::Test {
virtual ~VideoProcessorIntegrationTest() {}
void SetUp() {
encoder_ = new VP8Encoder();
decoder_ = new VP8Decoder();
encoder_ = VP8Encoder::Create();
decoder_ = VP8Decoder::Create();
// Setup the TestConfig struct for processing of a clip in CIF resolution.
config_.input_filename =

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@ -1,5 +1,5 @@
/*
* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
* Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
@ -462,8 +462,8 @@ int main(int argc, char* argv[]) {
PrintConfigurationSummary(config);
webrtc::VP8Encoder encoder;
webrtc::VP8Decoder decoder;
webrtc::VP8Encoder* encoder = webrtc::VP8Encoder::Create();
webrtc::VP8Decoder* decoder = webrtc::VP8Decoder::Create();
webrtc::test::Stats stats;
webrtc::test::FrameReaderImpl frame_reader(config.input_filename,
config.frame_length_in_bytes);
@ -475,7 +475,7 @@ int main(int argc, char* argv[]) {
webrtc::test::PacketManipulatorImpl packet_manipulator(
&packet_reader, config.networking_config, config.verbose);
webrtc::test::VideoProcessorImpl processor(&encoder, &decoder,
webrtc::test::VideoProcessorImpl processor(encoder, decoder,
&frame_reader,
&frame_writer,
&packet_manipulator,
@ -494,8 +494,8 @@ int main(int argc, char* argv[]) {
Log("Processed %d frames\n", frame_number);
// Release encoder and decoder to make sure they have finished processing.
encoder.Release();
decoder.Release();
encoder->Release();
decoder->Release();
// Verify statistics are correct:
assert(frame_number == static_cast<int>(stats.stats_.size()));
@ -517,6 +517,8 @@ int main(int argc, char* argv[]) {
if (FLAGS_python) {
PrintPythonOutput(config, stats, ssim_result, psnr_result);
}
delete encoder;
delete decoder;
Log("Quality test finished!");
return 0;
}

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@ -1,19 +1,15 @@
/*
* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
* Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
/*
* vp8.h
*
* WEBRTC VP8 wrapper interface
*/
#ifndef WEBRTC_MODULES_VIDEO_CODING_CODECS_VP8_H_
#define WEBRTC_MODULES_VIDEO_CODING_CODECS_VP8_H_
@ -32,243 +28,231 @@ namespace webrtc
class TemporalLayers;
class ReferencePictureSelection;
/******************************/
/* VP8Encoder class */
/******************************/
class VP8Encoder : public VideoEncoder
{
public:
VP8Encoder();
class VP8Encoder : public VideoEncoder {
public:
static VP8Encoder* Create();
virtual ~VP8Encoder();
// Free encoder memory.
//
// Return value : WEBRTC_VIDEO_CODEC_OK if OK, < 0 otherwise.
virtual WebRtc_Word32 Release();
// Free encoder memory.
//
// Return value : WEBRTC_VIDEO_CODEC_OK if OK, < 0 otherwise.
virtual int Release();
// Reset encoder state and prepare for a new call.
//
// Return value : WEBRTC_VIDEO_CODEC_OK if OK, < 0 otherwise.
// <0 - Errors:
// WEBRTC_VIDEO_CODEC_ERR_PARAMETER
// WEBRTC_VIDEO_CODEC_ERROR
virtual WebRtc_Word32 Reset();
// Reset encoder state and prepare for a new call.
//
// Return value : WEBRTC_VIDEO_CODEC_OK if OK, < 0 otherwise.
// <0 - Errors:
// WEBRTC_VIDEO_CODEC_ERR_PARAMETER
// WEBRTC_VIDEO_CODEC_ERROR
virtual int Reset();
// Initialize the encoder with the information from the codecSettings
//
// Input:
// - codecSettings : Codec settings
// - numberOfCores : Number of cores available for the encoder
// - maxPayloadSize : The maximum size each payload is allowed
// to have. Usually MTU - overhead.
//
// Return value : Set bit rate if OK
// <0 - Errors:
// WEBRTC_VIDEO_CODEC_ERR_PARAMETER
// WEBRTC_VIDEO_CODEC_ERR_SIZE
// WEBRTC_VIDEO_CODEC_LEVEL_EXCEEDED
// WEBRTC_VIDEO_CODEC_MEMORY
// WEBRTC_VIDEO_CODEC_ERROR
virtual WebRtc_Word32 InitEncode(const VideoCodec* codecSettings,
WebRtc_Word32 numberOfCores,
WebRtc_UWord32 maxPayloadSize);
// Initialize the encoder with the information from the codecSettings
//
// Input:
// - codec_settings : Codec settings
// - number_of_cores : Number of cores available for the encoder
// - max_payload_size : The maximum size each payload is allowed
// to have. Usually MTU - overhead.
//
// Return value : Set bit rate if OK
// <0 - Errors:
// WEBRTC_VIDEO_CODEC_ERR_PARAMETER
// WEBRTC_VIDEO_CODEC_ERR_SIZE
// WEBRTC_VIDEO_CODEC_LEVEL_EXCEEDED
// WEBRTC_VIDEO_CODEC_MEMORY
// WEBRTC_VIDEO_CODEC_ERROR
virtual int InitEncode(const VideoCodec* codec_settings,
int number_of_cores,
uint32_t max_payload_size);
// Encode an I420 image (as a part of a video stream). The encoded image
// will be returned to the user through the encode complete callback.
//
// Input:
// - inputImage : Image to be encoded
// - frameTypes : Frame type to be generated by the encoder.
//
// Return value : WEBRTC_VIDEO_CODEC_OK if OK
// <0 - Errors:
// WEBRTC_VIDEO_CODEC_ERR_PARAMETER
// WEBRTC_VIDEO_CODEC_MEMORY
// WEBRTC_VIDEO_CODEC_ERROR
// WEBRTC_VIDEO_CODEC_TIMEOUT
// Encode an I420 image (as a part of a video stream). The encoded image
// will be returned to the user through the encode complete callback.
//
// Input:
// - input_image : Image to be encoded
// - frame_types : Frame type to be generated by the encoder.
//
// Return value : WEBRTC_VIDEO_CODEC_OK if OK
// <0 - Errors:
// WEBRTC_VIDEO_CODEC_ERR_PARAMETER
// WEBRTC_VIDEO_CODEC_MEMORY
// WEBRTC_VIDEO_CODEC_ERROR
// WEBRTC_VIDEO_CODEC_TIMEOUT
virtual WebRtc_Word32 Encode(const RawImage& inputImage,
const CodecSpecificInfo* codecSpecificInfo,
const VideoFrameType* frameTypes);
virtual int Encode(const RawImage& input_image,
const CodecSpecificInfo* codec_specific_info,
const VideoFrameType* frame_types);
// Register an encode complete callback object.
//
// Input:
// - callback : Callback object which handles encoded images.
//
// Return value : WEBRTC_VIDEO_CODEC_OK if OK, < 0 otherwise.
virtual WebRtc_Word32 RegisterEncodeCompleteCallback(EncodedImageCallback*
callback);
// Register an encode complete callback object.
//
// Input:
// - callback : Callback object which handles encoded images.
//
// Return value : WEBRTC_VIDEO_CODEC_OK if OK, < 0 otherwise.
virtual int RegisterEncodeCompleteCallback(EncodedImageCallback* callback);
// Inform the encoder of the new packet loss rate and the round-trip time of the
// network.
//
// - packetLoss : Fraction lost
// (loss rate in percent = 100 * packetLoss / 255)
// - rtt : Round-trip time in milliseconds
// Return value : WEBRTC_VIDEO_CODEC_OK if OK
// <0 - Errors:
// WEBRTC_VIDEO_CODEC_ERROR
//
virtual WebRtc_Word32 SetChannelParameters(WebRtc_UWord32 packetLoss,
int rtt);
// Inform the encoder of the new packet loss rate and the round-trip time of
// the network.
//
// - packet_loss : Fraction lost
// (loss rate in percent = 100 * packetLoss / 255)
// - rtt : Round-trip time in milliseconds
// Return value : WEBRTC_VIDEO_CODEC_OK if OK
// <0 - Errors: WEBRTC_VIDEO_CODEC_ERROR
//
virtual int SetChannelParameters(uint32_t packet_loss, int rtt);
// Inform the encoder about the new target bit rate.
//
// - newBitRate : New target bit rate
// - frameRate : The target frame rate
//
// Return value : WEBRTC_VIDEO_CODEC_OK if OK, < 0 otherwise.
virtual WebRtc_Word32 SetRates(WebRtc_UWord32 newBitRateKbit,
WebRtc_UWord32 frameRate);
// Inform the encoder about the new target bit rate.
//
// - new_bitrate_kbit : New target bit rate
// - frame_rate : The target frame rate
//
// Return value : WEBRTC_VIDEO_CODEC_OK if OK, < 0 otherwise.
virtual int SetRates(uint32_t new_bitrate_kbit, uint32_t frame_rate);
// Get version number for the codec.
//
// Input:
// - version : Pointer to allocated char buffer.
// - buflen : Length of provided char buffer.
//
// Output:
// - version : Version number string written to char buffer.
//
// Return value : >0 - Length of written string.
// <0 - WEBRTC_VIDEO_CODEC_ERR_SIZE
virtual WebRtc_Word32 Version(WebRtc_Word8 *version,
WebRtc_Word32 length) const;
static WebRtc_Word32 VersionStatic(WebRtc_Word8 *version,
WebRtc_Word32 length);
// Get version number for the codec.
//
// Input:
// - version : Pointer to allocated char buffer.
// - length : Length of provided char buffer.
//
// Output:
// - version : Version number string written to char buffer.
//
// Return value : >0 - Length of written string.
// <0 - WEBRTC_VIDEO_CODEC_ERR_SIZE
virtual int Version(char *version, int length) const;
static int VersionStatic(char *version, int length);
private:
VP8Encoder();
private:
// Call encoder initialize function and set control settings.
WebRtc_Word32 InitAndSetControlSettings();
int InitAndSetControlSettings();
void PopulateCodecSpecific(CodecSpecificInfo* codec_specific,
const vpx_codec_cx_pkt& pkt);
WebRtc_Word32 GetEncodedFrame(const RawImage& input_image);
int GetEncodedFrame(const RawImage& input_image);
WebRtc_Word32 GetEncodedPartitions(const RawImage& input_image);
int GetEncodedPartitions(const RawImage& input_image);
// Determine maximum target for Intra frames
//
// Input:
// - optimalBuffersize : Optimal buffer size
// Return Value : Max target size for Intra frames represented as
// percentage of the per frame bandwidth
WebRtc_UWord32 MaxIntraTarget(WebRtc_UWord32 optimalBuffersize);
// Determine maximum target for Intra frames
//
// Input:
// - optimal_buffer_size : Optimal buffer size
// Return Value : Max target size for Intra frames represented as
// percentage of the per frame bandwidth
uint32_t MaxIntraTarget(uint32_t optimal_buffer_size);
EncodedImage _encodedImage;
EncodedImageCallback* _encodedCompleteCallback;
WebRtc_Word32 _width;
WebRtc_Word32 _height;
WebRtc_Word32 _maxBitRateKbit;
WebRtc_UWord32 _maxFrameRate;
bool _inited;
WebRtc_UWord32 _timeStamp;
WebRtc_UWord16 _pictureID;
WebRtc_UWord8 _simulcastIdx;
bool _feedbackModeOn;
int _cpuSpeed;
WebRtc_UWord32 _rcMaxIntraTarget;
int _tokenPartitions;
ReferencePictureSelection* _rps;
TemporalLayers* _temporalLayers;
vpx_codec_ctx_t* _encoder;
vpx_codec_enc_cfg_t* _cfg;
vpx_image_t* _raw;
};// end of VP8Encoder class
EncodedImage encoded_image_;
EncodedImageCallback* encoded_complete_callback_;
VideoCodec codec_;
bool inited_;
uint32_t timestamp_;
uint16_t picture_id_;
bool feedback_mode_;
int cpu_speed_;
uint32_t rc_max_intra_target_;
int token_partitions_;
ReferencePictureSelection* rps_;
TemporalLayers* temporal_layers_;
vpx_codec_ctx_t* encoder_;
vpx_codec_enc_cfg_t* config_;
vpx_image_t* raw_;
}; // end of VP8Encoder class
class VP8Decoder : public VideoDecoder {
public:
static VP8Decoder* Create();
/******************************/
/* VP8Decoder class */
/******************************/
class VP8Decoder : public VideoDecoder
{
public:
VP8Decoder();
virtual ~VP8Decoder();
// Initialize the decoder.
//
// Return value : WEBRTC_VIDEO_CODEC_OK.
// <0 - Errors:
// WEBRTC_VIDEO_CODEC_ERROR
virtual WebRtc_Word32 InitDecode(const VideoCodec* inst,
WebRtc_Word32 numberOfCores);
// Initialize the decoder.
//
// Return value : WEBRTC_VIDEO_CODEC_OK.
// <0 - Errors:
// WEBRTC_VIDEO_CODEC_ERROR
virtual int InitDecode(const VideoCodec* inst, int number_of_cores);
// Decode encoded image (as a part of a video stream). The decoded image
// will be returned to the user through the decode complete callback.
//
// Input:
// - inputImage : Encoded image to be decoded
// - missingFrames : True if one or more frames have been lost
// since the previous decode call.
// - fragmentation : Specifies the start and length of each VP8
// partition.
// - codecSpecificInfo : pointer to specific codec data
// - renderTimeMs : Render time in Ms
//
// Return value : WEBRTC_VIDEO_CODEC_OK if OK
// <0 - Errors:
// WEBRTC_VIDEO_CODEC_ERROR
// WEBRTC_VIDEO_CODEC_ERR_PARAMETER
virtual WebRtc_Word32 Decode(const EncodedImage& inputImage,
bool missingFrames,
// Decode encoded image (as a part of a video stream). The decoded image
// will be returned to the user through the decode complete callback.
//
// Input:
// - input_image : Encoded image to be decoded
// - missing_frames : True if one or more frames have been lost
// since the previous decode call.
// - fragmentation : Specifies the start and length of each VP8
// partition.
// - codec_specific_info : pointer to specific codec data
// - render_time_ms : Render time in Ms
//
// Return value : WEBRTC_VIDEO_CODEC_OK if OK
// <0 - Errors:
// WEBRTC_VIDEO_CODEC_ERROR
// WEBRTC_VIDEO_CODEC_ERR_PARAMETER
virtual int Decode(const EncodedImage& input_image,
bool missing_frames,
const RTPFragmentationHeader* fragmentation,
const CodecSpecificInfo* codecSpecificInfo,
WebRtc_Word64 /*renderTimeMs*/);
const CodecSpecificInfo* codec_specific_info,
int64_t /*render_time_ms*/);
// Register a decode complete callback object.
//
// Input:
// - callback : Callback object which handles decoded images.
//
// Return value : WEBRTC_VIDEO_CODEC_OK if OK, < 0 otherwise.
virtual WebRtc_Word32 RegisterDecodeCompleteCallback(DecodedImageCallback*
callback);
// Register a decode complete callback object.
//
// Input:
// - callback : Callback object which handles decoded images.
//
// Return value : WEBRTC_VIDEO_CODEC_OK if OK, < 0 otherwise.
virtual int RegisterDecodeCompleteCallback(DecodedImageCallback* callback);
// Free decoder memory.
//
// Return value : WEBRTC_VIDEO_CODEC_OK if OK
// <0 - Errors:
// WEBRTC_VIDEO_CODEC_ERROR
virtual WebRtc_Word32 Release();
// Free decoder memory.
//
// Return value : WEBRTC_VIDEO_CODEC_OK if OK
// <0 - Errors:
// WEBRTC_VIDEO_CODEC_ERROR
virtual int Release();
// Reset decoder state and prepare for a new call.
//
// Return value : WEBRTC_VIDEO_CODEC_OK.
// <0 - Errors:
// WEBRTC_VIDEO_CODEC_UNINITIALIZED
// WEBRTC_VIDEO_CODEC_ERROR
virtual WebRtc_Word32 Reset();
// Reset decoder state and prepare for a new call.
//
// Return value : WEBRTC_VIDEO_CODEC_OK.
// <0 - Errors:
// WEBRTC_VIDEO_CODEC_UNINITIALIZED
// WEBRTC_VIDEO_CODEC_ERROR
virtual int Reset();
// Create a copy of the codec and its internal state.
//
// Return value : A copy of the instance if OK, NULL otherwise.
// Create a copy of the codec and its internal state.
//
// Return value : A copy of the instance if OK, NULL otherwise.
virtual VideoDecoder* Copy();
private:
// Copy reference image from this _decoder to the _decoder in copyTo. Set which
// frame type to copy in _refFrame->frame_type before the call to this function.
int CopyReference(VP8Decoder* copyTo);
private:
VP8Decoder();
WebRtc_Word32 DecodePartitions(const EncodedImage& input_image,
// Copy reference image from this _decoder to the _decoder in copyTo. Set
// which frame type to copy in _refFrame->frame_type before the call to
// this function.
int CopyReference(VP8Decoder* copy);
int DecodePartitions(const EncodedImage& input_image,
const RTPFragmentationHeader* fragmentation);
WebRtc_Word32 ReturnFrame(const vpx_image_t* img, WebRtc_UWord32 timeStamp);
int ReturnFrame(const vpx_image_t* img, uint32_t timeStamp);
RawImage _decodedImage;
DecodedImageCallback* _decodeCompleteCallback;
bool _inited;
bool _feedbackModeOn;
vpx_dec_ctx_t* _decoder;
VideoCodec* _inst;
WebRtc_Word32 _numCores;
EncodedImage _lastKeyFrame;
int _imageFormat;
vpx_ref_frame_t* _refFrame;
int _propagationCnt;
bool _latestKeyFrameComplete;
};// end of VP8Decoder class
RawImage decoded_image_;
DecodedImageCallback* decode_complete_callback_;
bool inited_;
bool feedback_mode_;
vpx_dec_ctx_t* decoder_;
VideoCodec codec_;
EncodedImage last_keyframe_;
int image_format_;
vpx_ref_frame_t* ref_frame_;
int propagation_cnt_;
bool latest_keyframe_complete_;
}; // end of VP8Decoder class
} // namespace webrtc
#endif // WEBRTC_MODULES_VIDEO_CODING_CODECS_VP8_H_

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@ -1,5 +1,5 @@
/*
* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
* Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
@ -15,34 +15,25 @@
using namespace webrtc;
VP8Benchmark::VP8Benchmark()
:
Benchmark("VP8Benchmark", "VP8 benchmark over a range of test cases",
webrtc::test::OutputPath() + "VP8Benchmark.txt", "VP8")
{
: Benchmark("VP8Benchmark", "VP8 benchmark over a range of test cases",
webrtc::test::OutputPath() + "VP8Benchmark.txt", "VP8") {
}
VP8Benchmark::VP8Benchmark(std::string name, std::string description)
:
Benchmark(name, description, webrtc::test::OutputPath() + "VP8Benchmark.txt",
"VP8")
{
: Benchmark(name, description,
webrtc::test::OutputPath() + "VP8Benchmark.txt",
"VP8") {
}
VP8Benchmark::VP8Benchmark(std::string name, std::string description,
std::string resultsFileName)
:
Benchmark(name, description, resultsFileName, "VP8")
{
: Benchmark(name, description, resultsFileName, "VP8") {
}
VideoEncoder*
VP8Benchmark::GetNewEncoder()
{
return new VP8Encoder();
VideoEncoder* VP8Benchmark::GetNewEncoder() {
return VP8Encoder::Create();
}
VideoDecoder*
VP8Benchmark::GetNewDecoder()
{
return new VP8Decoder();
VideoDecoder* VP8Benchmark::GetNewDecoder() {
return VP8Decoder::Create();
}

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@ -1,5 +1,5 @@
/*
* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
* Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
@ -18,14 +18,14 @@
VP8RpsTest::VP8RpsTest(float bitRate)
: VP8NormalAsyncTest(bitRate),
decoder2_(new webrtc::VP8Decoder),
decoder2_(webrtc::VP8Decoder::Create()),
sli_(false) {
}
VP8RpsTest::VP8RpsTest()
: VP8NormalAsyncTest("VP8 Reference Picture Selection Test",
"VP8 Reference Picture Selection Test", 1),
decoder2_(new webrtc::VP8Decoder),
decoder2_(webrtc::VP8Decoder::Create()),
sli_(false) {
}

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@ -1,5 +1,5 @@
/*
* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
* Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
@ -45,8 +45,8 @@ int main()
std::vector<Test*>::iterator it;
for (it = tests.begin() ; it < tests.end(); it++)
{
enc = new VP8Encoder();
dec = new VP8Decoder();
enc = VP8Encoder::Create();
dec = VP8Decoder::Create();
(*it)->SetEncoder(enc);
(*it)->SetDecoder(dec);
(*it)->SetLog(&log);

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@ -143,7 +143,7 @@ VCMGenericEncoder* VCMCodecDataBase::CreateEncoder(
{
#ifdef VIDEOCODEC_VP8
case kVideoCodecVP8:
return new VCMGenericEncoder(*(new VP8Encoder));
return new VCMGenericEncoder(*(VP8Encoder::Create()));
#endif
#ifdef VIDEOCODEC_I420
case kVideoCodecI420:
@ -739,7 +739,7 @@ VCMCodecDataBase::CreateDecoder(VideoCodecType type) const
{
#ifdef VIDEOCODEC_VP8
case kVideoCodecVP8:
return new VCMGenericDecoder(*(new VP8Decoder), _id);
return new VCMGenericDecoder(*(VP8Decoder::Create()), _id);
#endif
#ifdef VIDEOCODEC_I420
case kVideoCodecI420:

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@ -1,5 +1,5 @@
/*
* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
* Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
@ -181,12 +181,12 @@ CodecDataBaseTest::Perform(CmdArgs& args)
_vcm->InitializeReceiver();
VP8Decoder* decoder = new VP8Decoder;
VP8Decoder* decoder = VP8Decoder::Create();
VideoCodec vp8DecSettings;
VideoCodingModule::Codec(kVideoCodecVP8, &vp8DecSettings);
TEST(_vcm->RegisterExternalDecoder(decoder, vp8DecSettings.plType, false) == VCM_OK);
TEST(_vcm->RegisterReceiveCodec(&vp8DecSettings, 1, false) == VCM_OK);
VP8Encoder* encoder = new VP8Encoder;
VP8Encoder* encoder = VP8Encoder::Create();
VideoCodec vp8EncSettings;
VideoCodingModule::Codec(kVideoCodecVP8, &vp8EncSettings);
_vcm->RegisterTransportCallback(_encodeCallback); // encode returns error if callback uninitialized