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Adding layer info consideration when applying FEC protection. In this first version, we hard code protection zero for non-base layer frames. As a future enhancement, an array should be passed from mediaOpt to set the protection per layer. A TODO was added in MediaOpt.

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Review URL: http://webrtc-codereview.appspot.com/330005

git-svn-id: http://webrtc.googlecode.com/svn/trunk@1238 4adac7df-926f-26a2-2b94-8c16560cd09d
This commit is contained in:
mikhal@webrtc.org
2011-12-19 19:04:49 +00:00
parent 190e88a6d3
commit 0e7d9d862a
9 changed files with 133 additions and 38 deletions
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74
src/modules/video_coding/main/source/media_opt_util.cc
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@@ -8,17 +8,21 @@
* be found in the AUTHORS file in the root of the source tree.
*/
#include "video_coding_defines.h"
#include "fec_tables_xor.h"
#include "er_tables_xor.h"
#include "nack_fec_tables.h"
#include "qm_select_data.h"
#include "media_opt_util.h"
#include "modules/video_coding/main/source/media_opt_util.h"
#include <math.h>
#include <float.h>
#include <limits.h>
#include "modules/interface/module_common_types.h"
#include "modules/video_coding/codecs/vp8/main/interface/vp8_common_types.h"
#include "modules/video_coding/main/interface/video_coding_defines.h"
#include "modules/video_coding/main/source/er_tables_xor.h"
#include "modules/video_coding/main/source/fec_tables_xor.h"
#include "modules/video_coding/main/source/nack_fec_tables.h"
#include "modules/video_coding/main/source/qm_select_data.h"
namespace webrtc {
VCMProtectionMethod::VCMProtectionMethod():
@@ -345,12 +349,8 @@ VCMFecMethod::ProtectionFactor(const VCMProtectionParameters* parameters)
// Use a smaller exponent (< 1) to control/soften system size effect.
const float resolnFac = 1.0 / powf(spatialSizeToRef, 0.3f);
const float bitRate = parameters->bitRate;
const float frameRate = parameters->frameRate;
const int bitRatePerFrame = BitsPerFrame(parameters);
// Average bits per frame (units of kbits)
const WebRtc_UWord16 bitRatePerFrame = static_cast<WebRtc_UWord16>
(bitRate / frameRate);
// Average number of packets per frame (source and fec):
const WebRtc_UWord8 avgTotPackets = 1 + (WebRtc_UWord8)
@@ -399,11 +399,17 @@ VCMFecMethod::ProtectionFactor(const VCMProtectionParameters* parameters)
codeRateDelta = kPacketLossMax - 1;
}
float adjustFec = _qmRobustness->AdjustFecFactor(codeRateDelta,
bitRate,
frameRate,
parameters->rtt,
packetLoss);
float adjustFec = 1.0f;
// Avoid additional adjustments when layers are active.
// TODO(mikhal/marco): Update adjusmtent based on layer info.
if (parameters->numLayers == 1)
{
adjustFec = _qmRobustness->AdjustFecFactor(codeRateDelta,
parameters->bitRate,
parameters->frameRate,
parameters->rtt,
packetLoss);
}
codeRateDelta = static_cast<WebRtc_UWord8>(codeRateDelta * adjustFec);
@@ -481,16 +487,36 @@ VCMFecMethod::ProtectionFactor(const VCMProtectionParameters* parameters)
}
// TODO (marpan): Set the UEP protection on/off for Key and Delta frames
_useUepProtectionK = _qmRobustness->SetUepProtection(codeRateKey, bitRate,
packetLoss, 0);
_useUepProtectionK = _qmRobustness->SetUepProtection(codeRateKey,
parameters->bitRate,
packetLoss,
0);
_useUepProtectionD = _qmRobustness->SetUepProtection(codeRateDelta, bitRate,
packetLoss, 1);
_useUepProtectionD = _qmRobustness->SetUepProtection(codeRateDelta,
parameters->bitRate,
packetLoss,
1);
// DONE WITH FEC PROTECTION SETTINGS
return true;
}
int VCMFecMethod::BitsPerFrame(const VCMProtectionParameters* parameters) {
// When temporal layers are available FEC will only be applied on the base
// layer.
const float bitRateRatio =
kVp8LayerRateAlloction[parameters->numLayers - 1][0];
float frameRateRatio = powf(1 / 2, parameters->numLayers - 1);
float bitRate = parameters->bitRate * bitRateRatio;
float frameRate = parameters->frameRate * frameRateRatio;
// TODO(mikhal): Update factor following testing.
float adjustmentFactor = 1;
// Average bits per frame (units of kbits)
return static_cast<int>(adjustmentFactor * bitRate / frameRate);
}
bool
VCMFecMethod::EffectivePacketLoss(const VCMProtectionParameters* parameters)
{
@@ -570,7 +596,8 @@ _packetsPerFrameKey(0.9999f),
_residualPacketLossFec(0),
_boostRateKey(2),
_codecWidth(0),
_codecHeight(0)
_codecHeight(0),
_numLayers(1)
{
Reset();
}
@@ -801,6 +828,10 @@ VCMLossProtectionLogic::UpdateFrameSize(WebRtc_UWord16 width,
_codecHeight = height;
}
void VCMLossProtectionLogic::UpdateNumLayers(int numLayers) {
_numLayers = (numLayers == 0) ? 1 : numLayers;
}
bool
VCMLossProtectionLogic::UpdateMethod()
{
@@ -820,6 +851,7 @@ VCMLossProtectionLogic::UpdateMethod()
_currentParameters.residualPacketLossFec = _residualPacketLossFec;
_currentParameters.codecWidth = _codecWidth;
_currentParameters.codecHeight = _codecHeight;
_currentParameters.numLayers = _numLayers;
return _selectedMethod->UpdateParameters(&_currentParameters);
}