search for: lbrr

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

...ARROWBAND 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, payload_length_bytes, NULL, frame_data,? ? ? ? ? ? ? ? ? ? ? ? frame_sizes, NULL) < 0) {? ? return 0;? } ? if (frame_sizes[0] <= 1) {? ? return 0;? } ? for (n = 0; n < channels; n++) {? ? if (frame_data[0][0] & (0x80 >> ((n + 1) * (frames...

Hi, I am looking at the conformance test using opus_compare and the test vectors and I am a bit confused about FEC. Is there a way to validate that a decoder processes LBRR frames correctly? Thanks, Alexis

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 recommend Regards Julien -------------- next part -------------- An HTML attachment was scrub...

For the last couple months, Nuance has performed extensive testing on how the Opus codec performs in the speech recognition task. I'm hoping to publish a full report in the coming months, but until then all I have is a teaser. Opus performed within about 1% of the WER (Word Error Rate) of unencoded audio. This is compared to about 5% for Speex, which was the previous codec of choice. Well

...bitrate=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, payload_length_bytes, NULL, frame_data, > frame_sizes, NULL) < 0) { > return 0; > } > > if (frame_sizes[0] <= 1) { > return 0; > } > > for (n = 0; n < channels; n++) { >...

...opus_packet_get_nb_channels(payload); switch (payload_length_ms) { case 10: case 20: { frames = 1; break; } case 40: { frames = 2; break; } case 60: { frames = 3; break; } default: { return false; // It is actually even an invalid packet. } } /* The following is to parse the LBRR flags. */ if (opus_packet_parse(payload, (opus_int32)len, NULL, frame_data, frame_sizes, NULL) < 0) { return false; } if (frame_sizes[0] <= 1) { return false; } for (n = 0; n < channels; n++) { if (frame_data[0][0] & (0x80 >> ((n + 1) * (frames + 1) - 1))) return tr...

Hello all, after FOMS I decided to take a look at the opus library and I found that I could improve a bit the build system and cleanup the code a little bit. Most of the changes to the code has been suggested by my two tools cowstats and missingstatic (part of the ruby-elf gem if you care). HTH, Diego