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Pass NACK and FEC overhead rates through the ProtectionCallback to VCM.

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These overhead rates are used by the VCM to compensate the source
coding rate for NACK and FEC.

BUG=
TEST=

Review URL: http://webrtc-codereview.appspot.com/323003

git-svn-id: http://webrtc.googlecode.com/svn/trunk@1171 4adac7df-926f-26a2-2b94-8c16560cd09d
This commit is contained in:
stefan@webrtc.org
2011-12-13 15:38:14 +00:00
parent 1ced840893
commit f4c8286222
8 changed files with 113 additions and 59 deletions
Download Patch File Download Diff File Expand all files Collapse all files

75
src/modules/video_coding/main/source/media_optimization.cc
View File

@@ -22,7 +22,6 @@ _sendCodecType(kVideoCodecUnknown),
_codecWidth(0),
_codecHeight(0),
_userFrameRate(0),
_lossProtOverhead(0),
_packetLossEnc(0),
_fractionLost(0),
_sendStatisticsZeroEncode(0),
@@ -71,7 +70,6 @@ VCMMediaOptimization::Reset()
_lossProtLogic->Reset();
_sendStatisticsZeroEncode = 0;
_targetBitRate = 0;
_lossProtOverhead = 0;
_codecWidth = 0;
_codecHeight = 0;
_userFrameRate = 0;
@@ -124,7 +122,7 @@ VCMMediaOptimization::SetTargetRates(WebRtc_UWord32 bitRate,
_lossProtLogic->UpdateFilteredLossPr(packetLossEnc);
// Rate cost of the protection methods
_lossProtOverhead = 0;
uint32_t protection_overhead_kbps = 0;
// Update protection settings, when applicable
if (selectedMethod)
@@ -137,24 +135,40 @@ VCMMediaOptimization::SetTargetRates(WebRtc_UWord32 bitRate,
// the protection method is set by the user via SetVideoProtection.
_lossProtLogic->UpdateMethod();
// Update protection callback with protection settings
UpdateProtectionCallback(selectedMethod);
// Get the bit cost of protection method
_lossProtOverhead = static_cast<WebRtc_UWord32>
(_lossProtLogic->RequiredBitRate() + 0.5f);
// Update protection callback with protection settings.
uint32_t sent_video_rate_bps = 0;
uint32_t sent_nack_rate_bps = 0;
uint32_t sent_fec_rate_bps = 0;
// Get the bit cost of protection method, based on the amount of
// overhead data actually transmitted (including headers) the last
// second.
UpdateProtectionCallback(selectedMethod,
&sent_video_rate_bps,
&sent_nack_rate_bps,
&sent_fec_rate_bps);
uint32_t sent_total_rate_bps = sent_video_rate_bps +
sent_nack_rate_bps + sent_fec_rate_bps;
// Estimate the overhead costs of the next second as staying the same
// wrt the source bitrate.
if (sent_total_rate_bps > 0) {
protection_overhead_kbps = static_cast<uint32_t>(bitRate *
static_cast<double>(sent_nack_rate_bps + sent_fec_rate_bps) /
sent_total_rate_bps + 0.5);
}
// Cap the overhead estimate to 50%.
if (protection_overhead_kbps > bitRate / 2)
protection_overhead_kbps = bitRate / 2;
// Get the effective packet loss for encoder ER
// when applicable, should be passed to encoder via fractionLost
packetLossEnc = selectedMethod->RequiredPacketLossER();
}
// Update encoding rates following protection settings
_frameDropper->SetRates(static_cast<float>(bitRate -
_lossProtOverhead), 0);
// Source coding rate: total rate - protection overhead
_targetBitRate = bitRate - _lossProtOverhead;
_targetBitRate = bitRate - protection_overhead_kbps;
// Update encoding rates following protection settings
_frameDropper->SetRates(static_cast<float>(_targetBitRate), 0);
if (_enableQm)
{
@@ -174,9 +188,11 @@ VCMMediaOptimization::SetTargetRates(WebRtc_UWord32 bitRate,
return _targetBitRate;
}
WebRtc_UWord32
VCMMediaOptimization::UpdateProtectionCallback(VCMProtectionMethod
*selectedMethod)
int VCMMediaOptimization::UpdateProtectionCallback(
VCMProtectionMethod *selected_method,
uint32_t* video_rate_bps,
uint32_t* nack_overhead_rate_bps,
uint32_t* fec_overhead_rate_bps)
{
if (!_videoProtectionCallback)
{
@@ -184,29 +200,32 @@ VCMMediaOptimization::UpdateProtectionCallback(VCMProtectionMethod
}
// Get the FEC code rate for Key frames (set to 0 when NA)
const WebRtc_UWord8
codeRateKeyRTP = selectedMethod->RequiredProtectionFactorK();
codeRateKeyRTP = selected_method->RequiredProtectionFactorK();
// Get the FEC code rate for Delta frames (set to 0 when NA)
const WebRtc_UWord8
codeRateDeltaRTP = selectedMethod->RequiredProtectionFactorD();
codeRateDeltaRTP = selected_method->RequiredProtectionFactorD();
// Get the FEC-UEP protection status for Key frames: UEP on/off
const bool
useUepProtectionKeyRTP = selectedMethod->RequiredUepProtectionK();
useUepProtectionKeyRTP = selected_method->RequiredUepProtectionK();
// Get the FEC-UEP protection status for Delta frames: UEP on/off
const bool
useUepProtectionDeltaRTP = selectedMethod->RequiredUepProtectionD();
useUepProtectionDeltaRTP = selected_method->RequiredUepProtectionD();
// NACK is on for NACK and NackFec protection method: off for FEC method
bool nackStatus = (selectedMethod->Type() == kNackFec ||
selectedMethod->Type() == kNack);
bool nackStatus = (selected_method->Type() == kNackFec ||
selected_method->Type() == kNack);
return _videoProtectionCallback->ProtectionRequest(codeRateDeltaRTP,
codeRateKeyRTP,
useUepProtectionDeltaRTP,
useUepProtectionKeyRTP,
nackStatus);
return _videoProtectionCallback->ProtectionRequest(codeRateDeltaRTP,
codeRateKeyRTP,
useUepProtectionDeltaRTP,
useUepProtectionKeyRTP,
nackStatus,
video_rate_bps,
nack_overhead_rate_bps,
fec_overhead_rate_bps);
}
bool

6
src/modules/video_coding/main/source/media_optimization.h
View File

@@ -139,7 +139,10 @@ private:
/*
* Update protection callback with protection settings
*/
WebRtc_UWord32 UpdateProtectionCallback(VCMProtectionMethod *selectedMethod);
int UpdateProtectionCallback(VCMProtectionMethod *selected_method,
uint32_t* total_video_rate_bps,
uint32_t* nack_overhead_rate_bps,
uint32_t* fec_overhead_rate_bps);
void UpdateBitRateEstimate(WebRtc_Word64 encodedLength, WebRtc_Word64 nowMs);
/*
@@ -168,7 +171,6 @@ private:
VCMFrameDropper* _frameDropper;
VCMLossProtectionLogic* _lossProtLogic;
WebRtc_UWord32 _lossProtOverhead;
WebRtc_UWord8 _packetLossEnc;
WebRtc_UWord8 _fractionLost;