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Update to media_opt_util:

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(1) update to off-line table for fec 
(2) corresponding update and some code-cleanup for  
    FecProtectionFactor()
Review URL: http://webrtc-codereview.appspot.com/93006

git-svn-id: http://webrtc.googlecode.com/svn/trunk@267 4adac7df-926f-26a2-2b94-8c16560cd09d
This commit is contained in:
marpan@google.com 2011-07-28 17:42:57 +00:00
parent 59e41405d1
commit 11d986a68c
2 changed files with 6427 additions and 6437 deletions
src/modules/video_coding/main/source
fec_tables_xor.hmedia_opt_util.cc

12780
src/modules/video_coding/main/source/fec_tables_xor.h

File diff suppressed because it is too large Load Diff

84
src/modules/video_coding/main/source/media_opt_util.cc

@ -306,9 +306,8 @@ VCMFecMethod::ProtectionFactor(const VCMProtectionParameters* parameters)
{
// FEC PROTECTION SETTINGS: varies with packet loss and bitrate
WebRtc_UWord8 packetLoss = (WebRtc_UWord8) (255 * parameters->lossPr);
// No protection if (filtered) packetLoss is 0
WebRtc_UWord8 packetLoss = (WebRtc_UWord8) (255 * parameters->lossPr);
if (packetLoss == 0)
{
_protectionFactorK = 0;
@ -316,62 +315,57 @@ VCMFecMethod::ProtectionFactor(const VCMProtectionParameters* parameters)
return true;
}
// Size of tables
// Parameters for FEC setting:
// first partition size, thresholds, table pars, spatial resoln fac.
// First partition protection: ~ 20%
WebRtc_UWord8 firstPartitionProt = (WebRtc_UWord8) (255 * 0.20);
// Threshold on packetLoss and bitRrate/frameRate (=average #packets),
// above which we allocate protection to cover at least first partition.
WebRtc_UWord8 lossThr = 0;
WebRtc_UWord8 packetNumThr = 1;
// Size of table
const WebRtc_UWord16 maxFecTableSize = 6450;
// Parameters for range of rate and packet loss for tables
const WebRtc_UWord8 ratePar1 = 5;
const WebRtc_UWord8 ratePar2 = 49;
const WebRtc_UWord8 plossMax = 129;
// Spatial resolution size, relative to a reference size.
float spatialSizeToRef = static_cast<float>
(parameters->codecWidth * parameters->codecHeight) /
(static_cast<float>(704 * 576));
// resolnFac: This parameter will generally increase/decrease the FEC rate
// (for fixed bitRate and packetLoss) based on system size.
// Use a smaller exponent (< 1) to control/soften system size effect.
const float resolnFac = 1.0 / pow(spatialSizeToRef, 0.3);
const float bitRate = parameters->bitRate;
const float frameRate = parameters->frameRate;
// Total (avg) bits available per frame: total rate over actual/frame_rate.
// Units are kbits/frame
// Average bits per frame (units of kbits)
const WebRtc_UWord16 bitRatePerFrame = static_cast<WebRtc_UWord16>
(bitRate /
(parameters->frameRate));
(bitRate / frameRate);
// TODO (marpan): Incorporate frame size (bpp) into FEC setting
// Total (avg) number of packets per frame (source and fec):
// Average number of packets per frame (source and fec):
const WebRtc_UWord8 avgTotPackets = 1 + (WebRtc_UWord8)
((float) bitRatePerFrame * 1000.0
/ (float) (8.0 * _maxPayloadSize) + 0.5);
// First partition protection: ~ 20%
WebRtc_UWord8 firstPartitionProt = (WebRtc_UWord8) (255 * 0.20);
// Threshold on packetLoss and bitRrate/frameRate (=average #packets),
// above which we allocate protection to cover at least roughly
// first partition size.
WebRtc_UWord8 lossThr = 0;
WebRtc_UWord8 packetNumThr = 1;
// Modulation of protection with available bits/frame (or avgTotpackets)
float weight1 = 0.5;
float weight2 = 0.5;
if (avgTotPackets > 4)
{
weight1 = 0.75;
weight2 = 0.25;
}
if (avgTotPackets > 6)
{
weight1 = 1.5;
weight2 = 0.;
}
// FEC rate parameters: for P and I frame
WebRtc_UWord8 codeRateDelta = 0;
WebRtc_UWord8 codeRateKey = 0;
// Get index for table: the FEC protection depends on the (average)
// available bits/frame. The range on the rate index corresponds to rates
// (bps) from 200k to 8000k, for 30fps
// Get index for table: the FEC protection depends on an effective rate.
// The range on the rate index corresponds to rates (bps)
// from ~200k to ~8000k, for 30fps
const WebRtc_UWord16 effRateFecTable = static_cast<WebRtc_UWord16>
(resolnFac * bitRatePerFrame);
WebRtc_UWord8 rateIndexTable =
(WebRtc_UWord8) VCM_MAX(VCM_MIN((bitRatePerFrame - ratePar1) /
ratePar1, ratePar2), 0);
(WebRtc_UWord8) VCM_MAX(VCM_MIN((effRateFecTable - ratePar1) /
ratePar1, ratePar2), 0);
// Restrict packet loss range to 50:
// current tables defined only up to 50%
@ -389,11 +383,6 @@ VCMFecMethod::ProtectionFactor(const VCMProtectionParameters* parameters)
if (packetLoss > lossThr && avgTotPackets > packetNumThr)
{
// Average with minimum protection level given by (average) total
// number of packets
codeRateDelta = static_cast<WebRtc_UWord8>((weight1 *
(float) codeRateDelta + weight2 * 255.0 / (float) avgTotPackets));
// Set a minimum based on first partition size.
if (codeRateDelta < firstPartitionProt)
{
@ -407,8 +396,9 @@ VCMFecMethod::ProtectionFactor(const VCMProtectionParameters* parameters)
codeRateDelta = plossMax - 1;
}
float adjustFec = _qmRobustness->AdjustFecFactor(codeRateDelta, bitRate,
parameters->frameRate,
float adjustFec = _qmRobustness->AdjustFecFactor(codeRateDelta,
bitRate,
frameRate,
parameters->rtt,
packetLoss);
@ -426,7 +416,7 @@ VCMFecMethod::ProtectionFactor(const VCMProtectionParameters* parameters)
packetFrameKey);
rateIndexTable = (WebRtc_UWord8) VCM_MAX(VCM_MIN(
1 + (boostKey * bitRatePerFrame - ratePar1) /
1 + (boostKey * effRateFecTable - ratePar1) /
ratePar1,ratePar2),0);
WebRtc_UWord16 indexTableKey = rateIndexTable * plossMax + packetLoss;