search for: fec

Hello, Is FEC supposed to work in NARROWBAND mode ?(with maxaveragebitrate=12000; maxplaybackrate=8000 ) ?I am having some confusing results, it appears that FEC is enabled in the encoder, but the decoder cannot find any packet with FEC. I am also wondering if this piece of code is correct (webrtc): /* The foll...

Hello, I understand the encoder provides an option for FEC to provide some protection against packet loss, but I don't understand the details of this arrangement. I'd appreciate answers to the following: * Adding FEC seems to change the encoded audio bit-stream itself, i.e., it doesn't just add additional protection bits, but also changes the...

Thanks. When you say that with fec enabled, the threshold is increased, do you mean the bitrate - i.e., you need higher bitrate with fec enabled to suppress crosstalk? Also, can you make any recommendations to decide whether to use fec or not? We are trying to tune the parameters appropriately. Audio quality and reduction of cros...

On 27/01/17 12:16 PM, Jon Lederman wrote: > When you say that with fec enabled, the threshold is increased, do > you mean the bitrate - i.e., you need higher bitrate with fec enabled > to suppress crosstalk? Correct. Another effect I forgot to mention is that Using FEC will actually force SILK/hybrid rather than CELT, so it's possible that disabling FEC mak...

Hi, One other question I was wondering about. Is the reason that we hear the crosstalk with fec and packet loss percentage>0 is that Opus uses information from the left channel to try to error correct the right channel and vice versa? I am trying to understand the origin of the crosstalk. Thanks. -Jon > On Jan 27, 2017, at 12:29 PM, Jon Lederman <jon at soniccloud.com> wrote: &g...

Hi, I'm trying to use the FEC feature. I have a service which does the encoding with OPUS_SET_INBAND_FEC(1) and OPUS_SET_PACKET_LOSS_PERC(20) with 10ms packets. I'm not clear on the decoding process though. 1- When a packet is lost, do I need to call decode with fec=1 ONLY or do I need to call decode with fec=0 after as we...

Hello, We have a use case where we want to record an opus RTP stream to a .opus file. We want to fill in any gaps in the stream, and we also want to take advantage of inband FEC whenever possible. The ogg/opus draft describes[1] how to fill in gaps by generating zero-byte frames, but I do not understand how (and if) FEC can be used. Is this possible, and if so, what is the recommended way of doing it? Which component(s) would be responsible for handling FEC: the muxer (e....

...e listened to using headphones or speakers setup for stereo listening If instead you have (e.g.) two different people talking in each channel and both are meant to be listened to independently, then pretending it's a stereo stream will actually hurt compression significantly. > 1) If we use fec, we can reduce cross-talk but increasing bitrate. > However, that should result in higher packet loss due to higher > bitrate. Packet loss may or may not be related to the bitrate. It depends on the network and I'm not the best person to help you about that. > 2) If we don’t use fec...

At this bitrate the encoder likely decides that it's better to put all the bits in the normal packet than use FEC. When you enable FEC it steals a lot of bits from the non-FEC content. Also, the use of FEC depends on the reported percentage of packet loss. The more loss there is, the lower the threshold for enabling FEC. Overall, the encoder attempt to make the best decision on a packet-per-packet basis as to...

HI All, We are trying to use Opus in a VoIP environment for sending stereo audio. We have noticed a phenomenon where when FEC is enabled and packet_loss_percentage>0, that there is a mixing of audio from the left channel into the right channel and vice versa. That is, rather than hearing each channel in its pristine form as it was in the file, there is a combination of right and left channels that is heard on the left...

...Thank you. Yes, we do need both channels independent. So, if we encode each channel separately, we will be sacrificing the compression ratio we would achieve with stereo encoding, correct? So, based on what you say here is my understanding. Please confirm this is correct or not: 1) If we use fec, we can reduce cross-talk but increasing bitrate. However, that should result in higher packet loss due to higher bitrate. 2) If we don’t use fec, we can have no crosstalk. However, then we have significant chance of packet loss. 3) We could encode each channel separately. In this case, we would...

...phones or speakers setup for stereo listening > If instead you have (e.g.) two different people talking in each channel > and both are meant to be listened to independently, then pretending it's > a stereo stream will actually hurt compression significantly. > >> 1) If we use fec, we can reduce cross-talk but increasing bitrate. >> However, that should result in higher packet loss due to higher >> bitrate. > > Packet loss may or may not be related to the bitrate. It depends on the > network and I'm not the best person to help you about that. >...

...elow) I am not able to add a second plane with good results. I tried with par(new=TRUE) but the output was very poor. I have found some previous discussions about this point but (apparently) without a clear solution. Any advice would be appreciated. Simone Tenan ################## library(popbio) fec<-seq(0.1,2,0.1) delta <- seq(0,0.6,0.05) lambda<-matrix(0,length(fec), length(delta)) S0=0.7 S1=0.8 S2=0.85 S3=S2 for (j in 1:length(delta)){ for (i in 1:length(fec)){ F1=0 F2=fec[i]*0.05 F3=fec[i]*0.3 M<-matrix(0,3,3) M[1,]<-c(F1,F2*S0*(1-...

...//raw.githubusercontent.com/datasets/covid-19/master/data/time-series-19-covid-combined.csv > datos <- read.csv("C:/Users/HP/Downloads/time-series-19-covid-combined.csv") > > library(data.table) > library(ggplot2) > library(anytime) > > df <-datos > > df[, fec:=anytime(fec)] Error in `:=`(fec, anytime(fec)) : Check that is.data.table(DT) == TRUE. Otherwise, := and `:=`(...) are defined for use in j, once only and in particular ways. See help(":="). > setkey(df,com,fec) Error in setkeyv(x, cols, verbose = verbose, physical = physical) : x...

Hi all, I try to enable FEC in the encoder using the macro OPUS_SET_INBAND_FEC and I set the packet loss percentage to a constant value of 30%, using the macro OPUS_SET_PACKET_LOSS_PERC. Please find my encoder settings below: opus: encoder fmtp (maxplaybackrate=8000;maxaveragebitrate=24000;sprop-stereo=1;cbr=1;useinbandfe...

Dear Opus community, I have a question about the SILK inband FEC. I am using the opus_demo (opus-1.2-alpha) for testing opus codec, and when I choose the "-inbandfec" option I get the exactly the same results when I don't add it to the command line. Are these results logical? Thank you in advance. Best regards, Ayoub. *--------------------BOUZI...

Hi, When we pass around 9K samples of only ambient noise (no voice), the encoder which is enabled FEC+DTX is detecting only some 140 frames as non-voice (returning only TOC, no frame content). We were expecting all or more to be identified as non-voice. Our idea was to check how the decoder re-generates the original ambient noise during the silence duration (when we feed NULL to decoder) when the...

having a hard time communicating on IRC, thank you gmaxwell, very informative. anyway, we were discussing the proper implementation of FEC on the decoder side. well, encoder side is just a boolean thing so that's alright. i gave an example where the receiver lost 5 rtp packets, 1 2 3 4 and 5 during which, we call opus_decode with a null pointer and fec=0 for every packet lost. now, when it receives the 6th packet, what do we do?...

...; > datos <- > > read.csv("C:/Users/HP/Downloads/time-series-19-covid-combined.csv") > > > > > > library(data.table) > > > library(ggplot2) > > > library(anytime) > > > > > > df <-datos > > > > > > df[, fec:=anytime(fec)] > > Error in `:=`(fec, anytime(fec)) : > > Check that is.data.table(DT) == TRUE. Otherwise, := and `:=`(...) are > > defined for use in j, once only and in particular ways. See help(":="). > > > setkey(df,com,fec) > > Error in setkeyv(x, c...

Hi guys,