Displaying 20 results from an estimated 1000 matches similar to: "FEC handling and conformance"
2015 Feb 05
2
VOIP: FEC and NARROWBAND
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 following is to parse the LBRR flags. */? if (opus_packet_parse(payload,
2015 Jan 05
1
FEC monitoring
Hi,
I would like to monitor FEC usage in order to include it in RTCP EX or
calculate MOS estimation, etc.
However the Opus codec library does not seem to expose such information.
"Was LBRR found and used or was it PLC ?"
I saw in WebRTC that they are using a technique to parse the "frame header"
WebRtcOpus_PacketHasFec()
It this something that is supported ?
What would you
2013 Jan 28
2
Opus FEC
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 encoded bits. This is easy to show by
2013 Jun 15
1
conformance testing of custom implementation
Thanks for the answer. I'll take a look at this tool and verify my implementation.
But I'd like to clarify the moment. If the following is applied for a test vector
Reference Float Point Encoder --> Reference Float Point Decoder --> Float Point Output
Reference Fixed Point Encoder --> Reference Float Point Decoder --> Fixed Point Output
And then, if Float Point Output and
2015 Feb 06
0
VOIP: FEC and NARROWBAND
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
2013 Jun 12
2
conformance testing of custom implementation
Hi,
I'm working on porting libopus and I'd like to get information how to test Opus Encoder properly.
There is information in RFC6716, that Opus Decoder's test files (http://opus-codec.org/testvectors/opus_testvectors.tar.gz) were created specifically to exercise all aspects of the decoder. Using these files, a custom implementation of libopus can be verified to be sure the Opus
2019 Jul 15
0
How to enable OPUS inband FEC
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;useinbandfec=1;usedtx=1)
opus: encode bw=narrow bitrate=24000 fch=auto vbr=0 fec=1
2015 Apr 07
1
opus testvectors
Dear all,
When I install the current version of opus-tools on my Ubuntu system, I have the following problem:
When I try to open the test vector 'testvector01.bit', I got the error message 'Decoding complete. This doesn't look like a Opus file'.
When I open the 'testvector01.bit.opus' the decoding works fine, but the tool opus_compare mentioned, that the number of
2015 May 06
0
opus_compare
Dear all,
is the program opus_compare capable of comparing each decoder output or is it only capable of comparing the decoded testvectors?
Or in other words:
Can I use the opus_compare for comparing the decoder output when I have encoded and decoded arbitrary speech files?
With best regards,
Martin
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2018 Mar 22
1
Using FEC
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 well?
2- How do I know up front the size of the pcm that I send to
2017 Jan 27
2
FEC and Stereo
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
2014 Jun 03
1
Question about FEC and ogg/opus
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
2017 May 08
2
The inband FEC option within Opus
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.
*--------------------BOUZIANE AyoubPhone : (+212) 633 092 157*
2016 Oct 04
2
encoder with FEC+DTX enabled but not detecting noise
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
2017 Jan 27
2
FEC and Stereo
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 crosstalk are critical for us.
Thanks again.
Jon
Sent from my
2017 Jan 27
1
FEC and Stereo
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:
>
2017 Jan 27
1
FEC and Stereo
On 27/01/17 12:29 PM, Jon Lederman wrote:
> 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?
Not necessarily. Stereo makes two assumptions:
1) It assumes the two channels are somehow correlated
2) It assumes the two channels are meant to be
2015 Aug 25
2
PLC Sounds Robotic - How to Implement FEC Wideband
I am specifically using Celt Wideband (48kHz) over WiFi multicast that naturally leads to lost packets and am trying to minimize the impact to the audio. I implemented PLC but the audio it produces is robotic. Have I implemented PLC correctly?
Checking the waveform it is using the previous received waveform to fill in a missing packet but not the full waveform so it has to repeat. Basically,
2017 Jan 27
2
FEC and Stereo
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 makes you use CELT, which