Adaptive Filter | ADPCM | ADSP | ADSP-2181 | Aliasing | AMR | Anti-Aliasing | ARMA | Autocorrelation | AutoCovariance | Beamforming | Bessel | Blackfin | Butterworth | C6713 | CCS | Chebyshev | CIC Filter | Circular Convolution | Code Composer Studio | Comb Filter | Compression | Convolution | Cross Correlation | DCT | Decimation | Deconvolution | Demodulation | DM642 | DSP Boards | DSP/BIOS | DTMF | Echo Cancellation | Equalization | Equalizer | ETSI | EZLITE (Ez-kit Lite) | FFT | FFTW | FIR Filter | Fixed Point | FSK | G.711 | G.723 | G.729 | Gaussian Noise | Goertzel | GPIO | Hilbert Transform | IFFT | IIR Filter | Interpolation | Invariance | JTAG | Kalman | Laplace Transform | Levinson | LPC | McBSP | MIPS | Modulation | MPEG | Multirate | Notch Filter | Nyquist | OFDM | Oversampling | Pink Noise | Pitch | PLL | Polyphase | QAM | QDMA | Quantization | Quantizer | Radar | Random Noise | Reed Solomon | Remez | Resampling | RTDX | Sampling | Sharc | TI C6711 | Undersampling | Viterbi | Wavelets | White Noise | Wiener Filter | Windowing | XDS510PP | Z Transform

Custom compression methods

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...

Re: Audio Compression

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...

Newbie Question

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...

Wavelets compression for circular data?

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...

Image compression DSP

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...

Low complexity compression algorithm

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...

Voice Compression for digital storage and playback

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...

DWT and Data Compression

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...

"Lena" or similar compression tests

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 ...

AAC compression chips? Other compression chips?

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...

Standard audio compression (LA-2A, not MP3) algorithm

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...

references for image compression with neural networks

Where can i find the recent literature on image compression with neural networks? ...

ask for help on Hi Fidelity Audio Compression with ADPCM

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...

ask for help on Hi Fidelity Audio Compression with ADPCM

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. ...

In what "dimension" does JPEG compression loss occur for color images

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? ...

Video Compression

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...

Wavelets for circular data?

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...

video compression java code

Hi there! Does anyone have a source code of any video compression algorithm in java? Thanks! ...

MPEG video compression

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. ...

dynamic compression/noisegating/sound schemes

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 ...

MPEG2 MP@LL and MPEG1?

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?? ...

Re: data file similarity metric/software

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...

DSP algorithm for Image compression

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...

Wavelet data compression

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...

Probably NAIVE question on (lossy?) voice compression

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...

G.728 re-entry algorithm

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 ...

switched ADPCM

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...

Re: Internet Stream Audio [Was Re: Bit-resolution decrease for internet]

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: Audio Artifacts: WAV vs. WMA

Erik de Castro Lopo wrote in message news: ... > Curious wrote: > > > > Low-bitrate WMA files have a pleasant type of distortion to them. > > Couldn't say the same about low-bitrate WAV files. > > > > WMA "noise" tends to be musical while WAV "noise" tends to resemble > > s...

Re: A better window than hanning

"thedude" wrote in message news:5f5a61f6.0412200611.3da80e5d@posting.google.com... > Hi > > Im working with DSP for a school project. > > We have made a sound compression program for wav files. > > We uses a hanning window and makes 50% overlap on our sound samples, > before w...

compression speed

Hello, I am wondering how much computation it takes to compress audio. This information is a little hard to come by. The general situation is this: I am working on a program that will record either from the sound cards of several computers or from some card that provides several raw audio c...

Re: ANNOUNCEMENT: New image format

He's Late schrieb: > I seem to have left out some important punctuation. Vista sucks, this is true, > but the HDR Photo(? I was in error in typing earlier) , HDPhoto format (*.hdp > and *.wdp filename extensions) has some very strong advantages, which got its > start through Vista. Full EX...

Re: MP3 Audio Quality Enhancement

Sagar wrote: > Hi All, > We are working to develop an Algorithm for Enhancing the > Quality of compressed audio. We are thinking of having High Frequncy > Reconstrucion. Fancy word for distortion ... > We are looking for the communities suggestion or > experience on "High F...

Re: ANNOUNCEMENT: New image format

John Costella schrieb: > 12:30 pm CST, November 22, 2007 > > > I am pleased to announce the release of a new image format, which I > have somewhat mischievously dubbed "JPEG-Clear", which is optimized > for the following uses, among others: > > * Transmission of images or image se...

Re: Beginner on DSP?

Tolga Onbay wrote: > I asked a question with subject "Voice Recorder?" a few days ago on > comp.arch.embedded. > > http://groups.google.com/group/comp.arch.embedded/browse_thread/thread/edfdae3e27e614f3 > > And then I asked again a question to comp.arch.embedded and they > forwarded ...

Re: U-Law compressed sound - best format when extract from .mov?

Andrew Thompson wrote: .. > I want to extract the sound to a separate (sound specific) > format for further editing, and am offered the choices (in > current software) of MP3, Wav, AIFF and AU. .. > Since MP3 is a lossy format, ... I am assuming here - lossy in a new and different way ...

wavelet question

hi all, Can anyone tell why wavelets are better than subband coding in image compression? thanx, sridevi ...

Re: 8bit to 16bit conversion

Hi all, I have successfully converted 8-bit samples to 16-bit values for my 16-bit codec. However I am facing another problem now. The 16-bit values that I read from the port are very large. Even at times when no speech exists (and only noise exists), the sample values are very large. I fo...

Vector Quantization using genetic algorithms

Hi everybody, I'm working on Image compression using VQ, does anyone have a C/C++ code for VQ implementation using GA? Appreciate your feedback ...

Formula to calculate the rate for a compression algorithm

Hi all, In the case I don't know the sampling frequency. Specifically, I only given a discrete function: f[n]= blah blah..... with length N. I use wavelet based compression method: Decompose the signal into N wavelet coefficients, quantize and then encode these coefficients with M bits...