generic-library/webrtc
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

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

Browse Source 
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