Displaying 20 results from an estimated 1000 matches similar to: "Stereo <-> Mono"
2011 Feb 15
1
CELT decoder complexity
Hi,
We're using Celt 0.7.1 at the moment. We're thinking to update the code to
a newer version of it. Is there an appreciable complexity (decoding time)
difference among versions (0.7.1 - 0.8.1 - 0.9.1 - 0.10 - 0.11.1)?
If so, which one is the fastest?
Thanks
Regards
Riccardo
Riccardo Micci
Senior DSP Engineer, Wireless Group
Cambridge Consultants
Science Park, Milton Road
2011 Mar 22
1
MAX_PERIOD
Hi,
In order to fit the decoder in memory in our embedded architecture we set
the MAX_PERIOD #define equal to the frame size. This doesn't affect the
code bit accuracy in normal decoding. The #define it's used
celt_decode_lost function though. Is it possible to get celt_decode_lost
to work with a value different from the default?
Thanks
Riccardo
Riccardo Micci
Senior DSP Engineer,
2010 Nov 25
1
Celt_decode_lost function (File: P0773)
Hi,
I'm using Celt version 0.7.1 in low complexity mode (i.e. no pitch
information). In case a packet is lost i was planning to use the
celt_decode_lost function. I realised though it uses pitch information
inside.
Does the celt_decode_lost function still works with no pitch information?
Are there some changes to be done?
Thanks
Regards
Riccardo
Riccardo Micci
Senior DSP Engineer,
2010 Aug 20
1
CELT complexity question
Hi,
I'm testing CELT 0.7.1 speed performance and I'm focusing now on the
complexity switch. I've dug in the archive and i found some information.
Is it still true that there are two ranges?
- 0-2 low complexity mode
- 3-10 high complexity mode
If no input is given is 2 hence low complexity mode the default setting?
Does the complexity mode affect decoding as well?
Thank you
Best
2011 Mar 03
1
Bitrev for FFT
Hi,
Our DSP has a built-in bitrev instruction so we're exploring the
possibility of calculating the bitrev every time instead of filling the
table during initialisation, hence saving some memory.
Our frame size is fixed to 320 samples. The two FFTs sizes for normal
block and short block are 160 and 40 respectively. It's not really clear
how the function
2010 Sep 24
1
Celt 0.7.1 High complexity VS Low complexity
Hi,
I was checking complexity modes of CELT 07.1 encoder. If i got it
correctly everything is driven by pitch_available variable set in
celt_encoder_create function. By default it's set to 1 hence high
complexity mode is used all the time. I tried to disable it and although i
couldn't hear any particular difference in the decoded audio quality, the
cycle count of the encoder dropped
2010 Jul 07
1
FIXED_POINT
Hi,
I've recently successful built and run CELT under Windows using
"testcelt.c" example file. Since I'm about to port it on a embedded
platform i activated the FIXED_POINT #define.
I included fixed_generic.h and without other changes to the code i tried
to encode and decode the same file i previously used.
The output though is completely saturated i.e. it jumps from -32768 to
2010 Jul 20
1
BYTES_PER_CHAR
Hello,
I'm porting CELT 0.7.1 to an embedded platform and unfortunately (at least
for me) CHAR is defined as 16 bits. I now got the vocoder compiling but
when i compare the encoded output with a windows build, they don't match.
Among the other problems i think that the char definition is one of the
biggest players. I've seen in arch.h the following definitions:
/* 2 on TI C5x DSP */
2010 Jun 07
0
No subject
eds to drag in the source and header files from the libcelt directory into =
the project and define HAVE_CONFIG_H is the project's pre-processor definit=
ion.
The tricky part is to build a config.h file. To get it to work on VS some =
of the important settings include.
=20
#define CELT_BUILD
#define USE_ALLOCA
#undef VAR_ARRAYS
#undef restrict
#undef HAVE_STDINT_H
#undef inline
#define
2010 Jun 24
2
Getting CELT to work under Windows
Hi,
My name is Riccardo Micci i downloaded the CELT source code and I compiled
it under Windows. This is meant to be a preliminary study for my company's
project.
When i run CELT it encodes and decodes the file back saying "Encoder
matches decoder!!". When i try to play the output though the result is
just noise and clicks.
The only changes I've applied are some #defines to
2010 Sep 08
1
Celt 0.7.1 Fixed math
Hi,
I'm using Celt 0.7.1 in fixed math mode. In the celt_encode function, if
the variable has_pitch is true, the function pitch_search is called.
Within this function the find_best_pitch subfunction is called.
Here the variable "float score;" is defined.
Is this right? I was expecting not to see any float declaration in the
fixed math code. Is it possible to redefine it as
2011 Mar 17
2
Error resilience
Hi,
We're testing CELT (version 0.7.1) error resilience capability. We've used
already celtdec packet-loss options. Hence we know what to expect in case
of whole packet loss.
How does Celt respond to a broken encoded packet? Is it always better to
discard it and decode the missing frame through decode_lost?
We have the hardware capability of protecting the frame with multiple
CRCs.
2010 Sep 02
1
Possible Bug
Hi,
Fiddling with Celt i found a possible bug. I'm using CELT 0.7.1, frame
size 256, sample rate 32k and bitrate 64k.
Here is the scenario: decoding side, celt_decode function.
The "dec" structure is created at each function call and it's initialized
with ec_dec_init function. The attribute "end_byte" is not initialized
though. Decoding a file the behaviour is the
2013 Jul 18
0
Help understand decoding of stereo vorbis data
Hi,
I'm trying to implement a vorbis decoder, and am having some trouble getting it to work with stereo vorbis data.
It's giving me some PCM output which is roughly right, but it has artefacts.
I think it's most likely something to do with my handling of floor decode/curve synthesis. My first thoughts are that I'm handling the submap number/floor mapping incorrectly;
I'm
2005 Nov 15
1
Mono encoding w/ a stereo source.
Crew,
I've run into something a little odd with the vorbis encoder and would
like some input.
I use SpacialAudio's SAM3 Broadcaster and am having problems with the
ogg encoder when I create a mono output stream. It seems as if the
signal level of the left and right sides are being combined before the
encoding process, leaving the sound muddy and overdriven. As such, if I
reduce
2020 Feb 14
0
opus-codec.org/comparison: Mono or Stereo?
Looking at the Opus comparison page[1], I can't figure out whether the
Opus/AAC/Vorbis/MP3 lines are meant to imply a mono or stereo
encoding. Could someone please update the caption to clarify this?
The single dot for G.711 is clearly mono, but for stereo music, are
the codecs at the top meant to converge near 128 kbps, or 256 kbps?
[1] http://opus-codec.org/comparison/
2020 Mar 31
0
opus-codec.org/comparison: Mono or Stereo?
Paul,
you may find the following page has more useful/accurate numbers than that diagram:
https://wiki.xiph.org/Opus_Recommended_Settings
________________________________
From: opus <opus-bounces at xiph.org> on behalf of Paul Marks <pmarks at google.com>
Sent: Thursday, February 13, 2020 6:31:39 PM
To: opus at xiph.org <opus at xiph.org>
Subject: [opus]
2004 Aug 06
1
Force mono encoding of a stereo file
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
Hello
For some reasons, I need to encode in mono a stereo wave file, as with
the --downmix option from oggenc.
I searched in speexenc man page and in the on line documentation,
unsuccessfully. Of course I could first use something like sox to down
mix my file, but it would be more practical to have an option directly
in speexenc.
- --
RIQUER
2005 Apr 14
1
How to convert multichannel to mono/stereo?
Sorry for the questions out of the mail list's subject.
1)
Could you help me with getting information on how
can I convert multichannecl (e.g. 5.1) non-encoded
(PCM) data into mono\stereo? I suppose this performed in
the manner like:
Left = x1*(Front Left)+x2*(Back Left)....
But is there exist commonly used standards to perform this task?
2)
It seems FLAC pjoject have been frozen for some
2017 Sep 25
2
Force Opus/CELT to encode 2 mono instead of 1 stereo
Hi, folks,
I have an old CELT thing that I'm updating to Opus and I'm trying to get
individual pieces upgraded. My first task is upgrading the CELT encoder
to Opus.
The old CELT thing treated the L and R channels as independent mono
streams, encoded them somehow with CELT to form one bitstream, sent one
bitstream across, and then unpacked it manually after the decoder.
Can I do that