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We found 497 threads matching "compression"
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bogfrog - 2008-08-04 22:54:00
I am working on audio, samples are 16 bits, values ranging from -1 to +1
for each sample. I want to implement what a paper I am reading calls
"amplitude compression." These are the 3 specifications given for the
amplitude compression I want to implement:
(1) Compression ratio of 8.94:1 for |A| ...
Hi. Just out of curiosity, has anyone designed and built their own
method for music compression. I realise that the ogg format is
open-source and relatively unencumbered by licencing issues. But I'm
curious if anyone has written their own compression method "because
they can".
Cheers,
Ross...
HyeeWang - 2009-05-04 02:57:00
What is "aggressive" compression technology?
How to identify a aggressive compression algo, especially in speech
coding domain, which is my interst.
Anyway, i am talking the concept of "aggressive " used here.
Any comments would be appreciated!
HyeeWang
...
Udhay wrote:
> Thanks for your reply.
>
> I want to know about the data compression of audio.
>
> i need some links regarding this.
>
> which algorithm is good example for audio compression?
MP3 is widely used for music and general sounds. Other methods are more
efficient for...
nija - 2007-05-25 06:44:00
Hi all,
I am new to the field of DSP/Video Compression. I wanted to learn MPEG
4 Video Compression standard in particular as it is required in my
current project which is about Live Video streaming using RTSP/RTP
protocol on the internet using MPEG 4 codec.
I have read some articles/ISO st...
Andre - 2008-11-06 06:08:00
Hi VDSP-Experts,
I am trying to use the "compression" feature of the loader on the BF533
with VDSP5.0 update 4.
I have ticked "enable compression" in project options and selected a
zlib init file in load/options. The only thing I modified from the
default one (ADSP-BF533_zlib_init_SDRAM.dx...
Ksen - 2006-08-16 09:35:00
Is anyone aware of doing wavelet based compression of arrays of angular
data (or phase data)?
Instead of normal grau=yscale images, you have values from 0-360 degree
(which you can quantize between 0-255), but if you have two neighboring
pixzels with values of 255 an d0, dont treat it like a disc...
amerdsp - 2006-04-20 20:20:00
Greetings,
I am looking for a low power image compression for a mobile
application. It is meant to compress image data from an image sensor
so it can be transmitted over GPRS.
Does anyone have any recommendations? Currently I am still looking
for a microcontroller, probably a PIC to do th...
Hi all,
I posted this to comp.comression but perhaps some one here can also help me.
I am working on a project related to 3D modelling, and need some simple
algorithm to transmit 3D meshes to cell phones. As 3D meshes have quite
large data and cell phone's CPU is not as powerful as that of a...
Kunal - 2004-06-18 16:17:00
I am making a Digital Dictation Machine and I need a solution to
digitize the voice, compress it and store it on a flash chip. It
should then also be able to decompress it and play it back through a
d/a. I need to control it using I2C.
Questions:
1) Which are the latest voice compression algo...
SteveSmith - 2008-05-28 16:37:00
Is this simply for data compression, or are you trying to extract key
parameters from the original data set?
If for data compression, is a lossy algorithm OK, or do you need it to be
lossless?
...
Hello
About the DWT:
The DWT provides data compression by setting a threshold value and all
coefficients that are less than the choosen value will be reduced to zero
or eliminated and the signal can be reconstructed from the thresholded
coefficients.
Therefore, I would like to ask about the lo...
2008-03-17 13:43:00
Does anyone have source data for any standard image compression images
such as "Lena" in integer/unsigned char format?
If not - is there an easy way I can obtain this by opening an image in
Matlab?
Cheers
Gary
...
eblade - 2008-09-20 09:28:00
After reading, what seems like a lot of material, I'm still in doubt why
DCT isnt used in audio-compression. Seeing as DCT assumes mirror symmetry,
my only idea for not validating DCT over MDCT is that with real-life
signals you can rarely (if ever) expect a signal to have that property? Is
that cor...
vasindagi - 2008-07-05 10:33:00
Its known that PSNR (peak signal to noise ratio) is used to compare image
quality after compression. Can it also be used for audio quality?
...
Dear All,
I'm looking for inexpensive hardware solution (chips) to encode groups
of 6 channel 44/48k signals into streams of preferably AAC. Or WMA or
MP3 or AC-3 if it is simpler.
The idea is that signal is input as regular 48k/24bit pcm, than the
user can select compression DR (eg 64kb...
Hi there, A quick question: Is there any way to compress the single
point floating point data? Apparently most of the research and
development work focuses on fixed point compression.
James
www.go-ci.com
...
HyeeWang - 2009-05-04 04:08:00
Compression artifacts in compressed audio typically show up as
ringing, pre-echo, drop-outs, warbling,
metallic ringing, an underwater feeling, hissing, or "graininess".
How and when the artifacts above occured? Where can i get the
appropriate speech samples to taste the effect?
More,anyone c...
cpshah99 - 2009-03-18 14:25:00
Hi All
As we know that due to relative motion between TX and RX, the transmitted
signal undergoes expansion/compression. And due to this symbol and phase
synchronization is lost.
I have simulated this perticular thing, where I am using matlab's resample
function to introduce this expansion/com...
This may be a FAQ, but I don't see one, and you guys seem pretty smart.
Is there a standard algorithm for doing audio compression in a DSP context?
I mean the type of compression that recording studios and radio stations
used to use a Universal LA2A or Universal Audio 1176LN. While these
are t...
Where can i find the recent literature on image compression with neural networks?
...
2008-12-05 00:07:00
Cognaxon has released "WSQ image library" for Texas Instruments family
microprocessors (embedded systems).
Importance of WSQ format:
Electronic fingerprints submitted to the FBI either through Integrated
Automated Fingerprint Identification System (IAFIS), or Electronic
Fingerprint Image Prin...
Jessecw - 2006-12-08 01:14:00
Hi all,
Currently, I am studying on how to get Hi Fidelity effects with
ADPCM related compression methods. But it seems that the traditional
IMA ADPCM and MS ADPCM will not get the satisfied results.
Any one can give me some suggestions? 16 bit PCM to 5 bit PCM will
be accepted by m...
jessecw - 2006-12-08 14:14:00
Hi all,
Currently, I am studying on how to get Hi Fidelity effects with ADPCM
related compression methods. But it seems that the traditional IMA ADPCM
and MS ADPCM will not get the satisfied results.
Any one can give me some suggestions? 16 bit PCM to 5 bit PCM will be
accepted by me.
...
I understand that JPEG is a "lossy" compression method.
For color images is loss in:
1. resolution
2. color depth
a. would that include contrast
3. resolution AND color depth
I intuitively suspect #3.
If so is it possible trade off resolution for color depth and vice versa?
...
Hello All,
The task is to transmit the grayscale video over the ethernet in the
real time. The input stream is 8bpp, 1024x768, 25fps. The compressed
stream should be no more then ~30Mbps. The available computing power is
~300MIPS of the general purpose DSP. It is desired to preserve as mu...
Ksen - 2006-08-16 13:03:00
Is anyone aware of doing wavelet based compression of arrays of angular
data (or phase data)?
Instead of normal grau=yscale images, you have values from 0-360 degree
(which you can quantize between 0-255), but if you have two neighboring
pixzels with values of 255 an d0, dont treat it like a...
nandoscherp - 2007-11-12 19:50:00
Hi there!
Does anyone have a source code of any video compression algorithm in
java?
Thanks!
...
Hi guys,
I'd like to know if some of you have already implemented MPEG (2 or 4)
video compression on DSP. What free source codes have you used ?
Could you give me some links to good free source codes ?
I've searched on the net but haven't found anything really good.
Thanks for your help.
...
hi NG
I want to develop an small extern device with a small DSP for improving
audio with dynamic compression, noise gating and sound schemes.
But before I can start with the hardware and software of the DSP I want to
test different algorithms on the PC.
Unfortunately I didn't find anything ...
cpshah99 - 2009-02-10 16:16:00
Hi
thanks a lot for ur reply.
I have done something using linear interpolation but then I should get
some kind of compression of the signal, but I am not getting that.
Now, my o/p sampling rate is 47968 Hz. so what i did was generate the
signal at 96 KHz and do linear interpolation. but ...
Davy - 2005-09-04 10:32:00
Hi all,
I heard that MPEG2 and MPEG1 use same compression methods.
MPEG2's MP@LL and MPEG1 are all 4:2:0, 352*288*30. But MPEG2's MP@LL is
4Mbit/s and MPEG1 is 1.5Mbit/s. Why they have different bit rates?
And if I want to do 352*288*30 video compression. Shall I choose MPEG2
or MPEG1??
...
Andor - 2005-03-22 05:21:00
Matt,
after having read your first two paragraphs, I was going to suggest
what you wrote in the third. Why don't you try a string alignment
algorithm? That also gives you quantitative measures for metrics and
quality / relevance of the alignment.
Another approach could be via the Kolmogorov...
Dear All,
I am a new member in this group, I am developing a image compression
algorithm on a texas dsp tms320c6701.The algorithms needs to be run
within 0.1 sec.The DSP has a processing speed of 160Mhz. What kind of
algorithm will I choose.I am looking for a algorithm that can compress
the ima...
Hello
I am trying to do some data compression using the DWT techniques but i
have encoutered some problems. Once i have set the threshold values, all
the DWT coefficients that were less than the chosen value were reduced to
zero which was the purpose. But on the other hand i would like to
recon...
I'm interested in settling in my own mind what makes speech intelligible.
In past wanderings of the WEB I have gathered the impression that
there are a wide variety of compression.decompression algorithms
available depending on your optimization target. Unfortunately, I
don't have a good re...
P.Krishna - 2006-07-12 10:16:00
Hi,
We have G.728 speech compression algorithm for ADSP218x DSP, as per my
understanging it works for only one channel. To make multiple channels
work we need to use G.728 re-entry algorithm for ADSP218x DSP, where can I
get this algorithm? earlier we bought G.728 speech compression algorithm
from ...
Jessecw - 2006-12-14 05:45:00
Hi All,
I am preparing to develop an real time audio compression codec for high
quality audio signals. Due to the heavy calculation burden, I will not
adopt MP3 as my compression algorithm.
I get from google search engine that there is an algorithm called
switched ADPCM that can code high q...
Chris Felton - 2009-01-15 11:48:00
> But where exactly does the time-domain aliasing occur in the
> reconstructed signal, and why?
In most applications, such as audio compression, the aliasing is
directly from the transform. You can go to the frequency domain and
back without any aliasing, using the DFT, DCT, etc. If you ...
Radium wrote:
> Transistor can only be "on" or "off". However, regions on a magnetic
> disc do not need to be,
So along with your CoDec (which is clearly impossible because compression
has been around for a long time, is well understood and has been proven that
you cannot compress a signal ...![Re: Internet Stream Audio [Was Re: Bit-resolution decrease for internet]](http://cdn.dsprelated.com/images/icon_more.jpg)
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