Displaying 20 results from an estimated 20000 matches similar to: "Encoding 2-Pass VBR?"
2015 Jan 22
2
Opus for speech: VBR vs CBR
Hi guys,
I'm using Opus for speech in wide-band mode (sampling rate 16000) and 20ms
frames with signal type set to SIGNAL_VOICE.
I have a few questions here:
1.
When I choose VBR mode, the codec seems to choose the bitrate on its own.
However, that seems to be an issue on mobile devices. In some cases, when I
configure the bitrate to say 20kbps, I see that the outgoing codec bitrate
at
2004 Aug 06
1
Frozen upper spectrum in WB VBR CNG
Jean-Marc Valin (jean-marc.valin@hermes.usherb.ca) wrote:
>
> > I've been using Speex in my voice-over-IP program on Win32, in
> > wideband (16kHz) mode. I just starting using VBR recently and
> > have run into something that might be a problem within Speex:
>
> Are you turning on DTX in addition to VBR? Also, what version are you
> using. As of 1.0, DTX is
2002 Aug 03
1
vbr / cbr / abr API calls
Hi,
Maybe this is documented somewhere, if so, please send me a link to the
documentation.
My question is: how to set up different (VBR, CBR, ABR) modes when
calling the Ogg Vorbis API?
Currently I do:
CBR:
ret = vorbis_encode_setup_managed( &vorbisInfo,
getInChannel(),
getOutSampleRate(),
2006 Apr 19
1
HW-Speex: Fileformat and encoding process
Hi
I have just written a small c programm which reads in speex files and outputs
them as asci text numbers. This is necessary as for writing a hw testbench
for decoding tests, since thy only read ascii files :-(.I can't read the
bitrate properly from the header file. It's allways -1. Please see example
below and attached c programm. I wan't to check for a fixed bitrate (8000).
2002 Aug 09
1
How to distinguish ABR & VBR ogg files?
I want to display info about Ogg files to Windows users.
The docs tell me how to distinguish CBR (nom=min=max bitrate), but how
do I distinguish between ABR and VBR streams?
When I created my Ogg files (with CDex) I set the 'quality'. Is there
some way to read this from the Ogg file?
Should I avoid calling the ov_bitrate function because it has to read
through the whole stream?
2004 Aug 06
2
vbr and music
I know speex is not supposed to do a great job compressing music, but
I've noticed that the new VBR code chokes completely when you try to
compress horns. I've placed a particularly offensive example up at
http://www.utdallas.edu/~matthias/ . Take a look at a-16m*{ogg,spx}.
a.ogg is the first minute of an ogg created from the source media (in
44khz stereo). The rest have been mixed down
2011 Jun 20
3
oggenc -q switch vs -b switch
Hello folks
I am encoding music to ogg vorbis format for the first time. From what
i have researched, ogg vorbis is natively a vbr format. Also encoding
using the -q switch is encouraged instead of specifying a bitrate
through -b.
Now, while encoding using -b i get this:
Encoding "file.wav" to
"file.ogg"
at approximate bitrate 224 kbps (VBR encoding enabled)
Notice
2004 Aug 06
2
--dtx alone does nothing?
> All you say look normal to me.
Okay, clarification requires less code to be written than a bug. :)
> > Does that makes sense? I would have thought that --dtx alone would have =
> doen it,
> > but maybe it needs perfect digital silence to work? Or only uses the voi=
> ce activation
> > to know when there's silence?
>
> DTX requires the VAD to know when
2004 Aug 06
1
Frozen upper spectrum in WB VBR CNG
Hi,
I've been using Speex in my voice-over-IP program on Win32, in
wideband (16kHz) mode. I just starting using VBR recently and
have run into something that might be a problem within Speex:
If someone hasn't spoken for a little while, and the bitrate drops
to very low, sometimes the high half of the spectrum becomes frozen
with a looping sound. The bottom half of the spectrum is
2009 Dec 15
2
Regression in wideband encoding quality between b1 and rc1
Hello,
To start with, thanks a lot for making such a great voice codec available!
Having recently upgrading to speex rc1, It occurred to us that there
seems to have been a regression in the quality of encoding since
version beta1.
We are compressing some 22khz wave files in wb mode with maximum
quality / complexity in VBR, and the result was really great with
speex beta1. With rc1 (or beta3),
2004 Aug 06
1
VBR reencoding @128k problem
I did some further investigating into this issue and here's what I found:
It appears somewhere between ices0.1.0 and ices 0.2.0 is where the "bug" (for lack of a better term) was introduced that i'm noticing. When I compile ices0.2.0 w/lame 3.89beta, the VBR is *NOT* reencoded, but instead streamed out at full VBR bitrate(s). However, when using ices0.1.0 w/lame 3.89beta, it
2010 May 17
1
Range Coding
Dear all,
I have been going through below mentioned update.
http://web.mit.edu/xiphmont/Public/theora/demo.html
I found this line-
Timothy Terriberry estimates a simple self-training range-coding
backend could be reasonably expected to decrease bit usage overhead by
15-20%.
Is it really true? I found one implementation....
http://svn.xiph.org/trunk/ghost/libentcode/
Did anyone verified this
2015 Jan 23
0
Opus for speech: VBR vs CBR
On 01/21/2015 07:51 PM, Daniel K wrote:
> Hi guys,
>
> I'm using Opus for speech in wide-band mode (sampling rate 16000) and
> 20ms frames with signal type set to SIGNAL_VOICE.
>
> I have a few questions here:
>
> 1.
> When I choose VBR mode, the codec seems to choose the bitrate on its own.
> However, that seems to be an issue on mobile devices. In some cases,
2008 Apr 11
3
Change target VBR on-the-fly?
Josh,
Yes, you can change VBR quality or ABR average bitrate at any time.
You don't need to do anything special. I use this feature (changing
VBR quality midstream) from time to time and it's quite convenient.
Tom
Joshua Gargus <schwa at fastmail.us> wrote:
>
> Hi there (from speex-dev newbie),
>
> Is it possible to change the target VBR on the fly? The
2003 Apr 29
3
VBR vs ABR
Hello,
I purchased the "CD Ripper 2" plugin for Winamp 3 and need help choosing
an ogg encoding format. It seems I have the choice between VBR and ABR
formatted oggs. I am familiar with VBR (variable bit rate) but not sure
what ABR stands for?
Is it possible/desirable to specify a bit rate when encoding oggs, or
does the nature of the ogg format make use of varying bit rates?
2010 May 12
1
Some queries regarding FLAC
Dear FLAC team,
I have some fundamental doubts regarding FLAC encoder:
1) In FLAC encoder there is no option of specifying the bitrate. There is
something called compression-level. I believe that based on the nature of
input WAV file and compression-level chosen bitrate is coming into picture.
As such there is no user control on the bitrate. Is that correct?
2) In FLAC encoder I am also not
2010 Feb 26
2
Are two passes useful in CBR mode ?
Hi,
I try to use the video tag to post videos on my blog
I'm using ffmeg2theora to transcode videos in theora
Resolution of 320x240 pixels and constant bitrate (CBR) of ~400 kbps
seems to be ok for publishing on my blog.
I've read that CBR is a better choice than VBR for web publishing
regarding the way TCP/IP works.
("In TCP it takes a while for a connection to increase its
2001 Jun 22
7
RE: [advanced] Response to Ogg Vorbis comments
> From: Jack Moffitt [mailto:jack@icecast.org]
>
> So in the very near future, I don't think that there will be any
> non-vorbis capable players. And for the most part, I think Vorbis
will
> be included in most players, though I have little hope that Microsoft
> will allow Vorbis to stand side-by-side with WMA.
There is a big difference between having a codec available for
2004 Aug 06
2
--dtx alone does nothing?
I'm running a:
for band in n w u
do
for quality in 0 1 2 3 4 5 6 7 8 9 10
do
for complexity in 3
do
for vad in "" "--vad"
do
for dtx in "" "--dtx"
do
echo speexenc -${band} --quality ${quality} --comp ${complexity} ${vad} ${dtx} input.${band}.wav
2001 Jul 03
2
ABR or CBR?
Just in case my quotation causeed misunderstnaing...
Forget about what I quoted before. Probably, by CBR, Monty meant ABR
since CBR is stupidly patented and this is the reason why Vorbis has
no CBR option. If you know this, it cannot be a problem but I see there
is a question asking what is ABR in the mailing list.
>On Thu 28 Jun 2001, 23:27:41 PDT, Monty (xiphmont@xiph.org)Wrote:
>then