Hi Jean-Marc and All,
Two things need your confirmation/suggestion.
1) First, I think there is a bug in libspeex/lsp.c line 512.
/* hard limit ak's to +/- 32767 */
if (a < -32767) a =32767; // This line should be changed to if (a
<
-32767) a = -32767;
if (a > 32767) a = 32767;
ak[j-1] = (short)a;
2) About the RTP wrapper for VoIP
I'd like to use the payload format defined in the SVN document rtp.txt as
below.
What I'm worry about is the interoperability with other implementations.
What's your opinion on that?
Best Regards,
Lianghu
//************************from the SVN /doc/rtp.txt begin
*************************************//
The Speex RTP payload is defined as a header, followed by any number of
requests to the remote encoder and all encoded speech frames.
+--------+----------+----------------+
| Header | Requests | Speech data... |
+--------+----------+----------------+
The header contains only the number of frames sent
encoded in 6 bits
0 1 2 3 4 5
+-+-+-+-+-+-+
| NB frames |
+-+-+-+-+-+-+
There can be any number of requests of the form
0 1 2 3 4 5 6 7 0 1
+-+-+-+-+-+-+-+-+-+-+
|R| ReqID | ReqVal |
+-+-+-+-+-+-+-+-+-+-+
where R is 1 when a request is following and 0 when there is no more
request. Each request (if R=1) is composed of a 4-bit request ID (ReqID) and
a 5-bit value (ReqVal)
Possible values for ReqID are:
0: REQ_PERSIST ReqVal=1 for persistent requests/mode selection,
0 otherwise
1: PERSIST_ACK Acknowledge a REQ_PERSIST from the other end,
ReqVal equals the value received
2: MODE Choose the encoder mode directly
3: QUALITY Choose the encoder quality
4: VBR Set VBR on (ReqVal=1) or off (ReqVal=2)
5: VBR_QUALITY Set the encoder quality for VBR mode
6: LOW_MODE Set the encoder mode for low-band (wideband only)
7: HIGH_MODE Set the encoder mode for high-band (wideband only)
All requests should be considered at the receiver as a suggestion and
compliance is not mandatory. The PERSIST_ACK should be sent upon receiving a
REQ_PERSIST request to indicate that the request has been received.
The speech data part contains speech frames one after the other. The size of
the encoded frames can be found since the mode is directly encoded into each
frame.
For example, a frame where we request VBR to be on with quality 8 and we
transmit two frames encoded at 8.35 kbps (167 bits/frame) will be:
0 1 2 3
0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| NB=2 |1|ReqID=2| ReqVal=0|1|ReqID=3|ReqVal=8 |0| frame 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| frame 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| frame 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| frame 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| frame 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| frame 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|end| frame 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| frame 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| frame 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| frame 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| frame 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| end frame 2 |P|P|P|P|P|P|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
//************************from the SVN /doc/rtp.txt end
*************************************//
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Jean-Marc Valin
2006-Nov-21 18:22 UTC
[Speex-dev] Re: One bug in the SVN and rtp wrapper issue
> 1) First, I think there is a bug in libspeex/lsp.c line 512. > > /* hard limit ak's to +/- 32767 */ > if (a < -32767) a =32767; // This line should be changed to if > (a < -32767) a = -32767; > if (a > 32767) a = 32767; > ak[j-1] = (short)a;Oops. Thanks for pointing that out. It's fixed in svn.> 2) About the RTP wrapper for VoIP > > I'd like to use the payload format defined in the SVN document rtp.txt > as below. > > What I'm worry about is the interoperability with other implementations. > > What's your opinion on that?Can you summarize what the issue is? Jean-Marc> Best Regards, > > Lianghu > > > //************************from the SVN /doc/rtp.txt begin > *************************************// > The Speex RTP payload is defined as a header, followed by any number of > requests to the remote encoder and all encoded speech frames. > > +--------+----------+----------------+ > | Header | Requests | Speech data... | > +--------+----------+----------------+ > > The header contains only the number of frames sent > encoded in 6 bits > > 0 1 2 3 4 5 > +-+-+-+-+-+-+ > | NB frames | > +-+-+-+-+-+-+ > > There can be any number of requests of the form > > 0 1 2 3 4 5 6 7 0 1 > +-+-+-+-+-+-+-+-+-+-+ > |R| ReqID | ReqVal | > +-+-+-+-+-+-+-+-+-+-+ > > where R is 1 when a request is following and 0 when there is no more > request. Each request (if R=1) is composed of a 4-bit request ID (ReqID) and > a 5-bit value (ReqVal) > > Possible values for ReqID are: > 0: REQ_PERSIST ReqVal=1 for persistent requests/mode selection, > 0 otherwise > 1: PERSIST_ACK Acknowledge a REQ_PERSIST from the other end, > ReqVal equals the value received > 2: MODE Choose the encoder mode directly > 3: QUALITY Choose the encoder quality > 4: VBR Set VBR on (ReqVal=1) or off (ReqVal=2) > 5: VBR_QUALITY Set the encoder quality for VBR mode > 6: LOW_MODE Set the encoder mode for low-band (wideband only) > 7: HIGH_MODE Set the encoder mode for high-band (wideband only) > > All requests should be considered at the receiver as a suggestion and > compliance is not mandatory. The PERSIST_ACK should be sent upon receiving a > REQ_PERSIST request to indicate that the request has been received. > > The speech data part contains speech frames one after the other. The size of > the encoded frames can be found since the mode is directly encoded into each > frame. > > For example, a frame where we request VBR to be on with quality 8 and we > transmit two frames encoded at 8.35 kbps (167 bits/frame) will be: > > 0 1 2 3 > 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > | NB=2 |1|ReqID=2| ReqVal=0|1|ReqID=3|ReqVal=8 |0| frame 1 | > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > | frame 1 | > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > | frame 1 | > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > | frame 1 | > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > | frame 1 | > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > | frame 1 | > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > |end| frame 2 | > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > | frame 2 | > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > | frame 2 | > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > | frame 2 | > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > | frame 2 | > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > | end frame 2 |P|P|P|P|P|P| > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > //************************from the SVN /doc/rtp.txt end > *************************************//
In a word, I don't what's the standard of speex payload format. The file doc/rtp.txt is for what? Is it not for rtp payload? I find that rtp.txt is more detail that draft02.txt Which rtp docment should be followed? Anyone else has written the RTP wrapper already? Lianghu On 11/22/06, Jean-Marc Valin <jean-marc.valin@usherbrooke.ca> wrote:> > > 1) First, I think there is a bug in libspeex/lsp.c line 512. > > > > /* hard limit ak's to +/- 32767 */ > > if (a < -32767) a =32767; // This line should be changed to if > > (a < -32767) a = -32767; > > if (a > 32767) a = 32767; > > ak[j-1] = (short)a; > > Oops. Thanks for pointing that out. It's fixed in svn. > > > 2) About the RTP wrapper for VoIP > > > > I'd like to use the payload format defined in the SVN document rtp.txt > > as below. > > > > What I'm worry about is the interoperability with other implementations. > > > > What's your opinion on that? > > Can you summarize what the issue is? > > Jean-Marc > > > Best Regards, > > > > Lianghu > > > > > > //************************from the SVN /doc/rtp.txt begin > > *************************************// > > The Speex RTP payload is defined as a header, followed by any number of > > requests to the remote encoder and all encoded speech frames. > > > > +--------+----------+----------------+ > > | Header | Requests | Speech data... | > > +--------+----------+----------------+ > > > > The header contains only the number of frames sent > > encoded in 6 bits > > > > 0 1 2 3 4 5 > > +-+-+-+-+-+-+ > > | NB frames | > > +-+-+-+-+-+-+ > > > > There can be any number of requests of the form > > > > 0 1 2 3 4 5 6 7 0 1 > > +-+-+-+-+-+-+-+-+-+-+ > > |R| ReqID | ReqVal | > > +-+-+-+-+-+-+-+-+-+-+ > > > > where R is 1 when a request is following and 0 when there is no more > > request. Each request (if R=1) is composed of a 4-bit request ID (ReqID) > and > > a 5-bit value (ReqVal) > > > > Possible values for ReqID are: > > 0: REQ_PERSIST ReqVal=1 for persistent requests/mode selection, > > 0 otherwise > > 1: PERSIST_ACK Acknowledge a REQ_PERSIST from the other end, > > ReqVal equals the value received > > 2: MODE Choose the encoder mode directly > > 3: QUALITY Choose the encoder quality > > 4: VBR Set VBR on (ReqVal=1) or off (ReqVal=2) > > 5: VBR_QUALITY Set the encoder quality for VBR mode > > 6: LOW_MODE Set the encoder mode for low-band (wideband only) > > 7: HIGH_MODE Set the encoder mode for high-band (wideband only) > > > > All requests should be considered at the receiver as a suggestion and > > compliance is not mandatory. The PERSIST_ACK should be sent upon > receiving a > > REQ_PERSIST request to indicate that the request has been received. > > > > The speech data part contains speech frames one after the other. The > size of > > the encoded frames can be found since the mode is directly encoded into > each > > frame. > > > > For example, a frame where we request VBR to be on with quality 8 and we > > transmit two frames encoded at 8.35 kbps (167 bits/frame) will be: > > > > 0 1 2 3 > > 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 > > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > | NB=2 |1|ReqID=2| ReqVal=0|1|ReqID=3|ReqVal=8 |0| frame 1 | > > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > | frame 1 | > > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > | frame 1 | > > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > | frame 1 | > > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > | frame 1 | > > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > | frame 1 | > > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > |end| frame 2 | > > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > | frame 2 | > > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > | frame 2 | > > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > | frame 2 | > > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > | frame 2 | > > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > | end frame 2 |P|P|P|P|P|P| > > +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ > > > > //************************from the SVN /doc/rtp.txt end > > *************************************// >-------------- next part -------------- An HTML attachment was scrubbed... URL: http://lists.xiph.org/pipermail/speex-dev/attachments/20061122/9555b36a/attachment.htm