FFT vs DCT3630 (9/26/2011 2:29:15 PM) comp.dsp Hi All, I'm trying to understand the differences between FFT and DCT and was hoping someone may be able to help me with a couple of questions. 1. Is DCT basically the same as an FFT that operates on real numb... Raeldor
DCT Code158 (9/11/2011 10:25:46 PM) comp.dsp I'm trying to roll my own DCT-II code to pass in an array of floats, each representing the log power of a mel frequency spectrum. I was expecting to get back positive amplitude values, but I am also getting ba... Raeldor
Voice Recognition over Bluetooth534 (8/28/2011 5:35:19 AM) comp.dsp Hi All, I was wondering how voice recognition systems that work over bluetooth cope with the potentially huge difference in the spectogram produced from the source or training samples versus that of a (let's f... Raeldor
FFT and Sine Waves Question3564 (8/26/2011 5:18:59 AM) comp.dsp Hi All, I was doing some experimenting and was wondering if someone could explain my results. I have a pure sine wave at 1000hz generated into a wave file. I also have some FFT code to produce a spectrograph... Raeldor
The Theory Behind Why DCT is Used for MFCC Feature Vectors?731 (3/14/2011 5:07:10 AM) comp.dsp Hi All, Does anyone have a good link to the theory behind why DCT is used for MFCC feature vectors? What exactly is it about the DCT values of the mel frequency spectrum that makes it so appealing for voice r... Raeldor
Formula to Find Resonant Frequencies?1023 (3/12/2011 11:01:43 PM) comp.dsp Hi All, Is there a formula or mathematical concept to find the resonant frequencies in a sound wave? Thanks Rael ... Raeldor
Auto-Covariance help729 (3/8/2011 12:42:16 AM) comp.dsp Hi All, I'm trying to calculate the auto co-variance of a 16khz audio signal. The signal has been normalized between -1.0 and 1.0. I am using the following explanation of co-variance to calculate the auto-cov... Raeldor
Voice Recognition Sample Rate vs Mel Channels1142 (2/26/2011 4:36:49 PM) comp.dsp Hi All,
I was sampling at 8000hz, and was using triangular overlapping windows
to produce 20 mel channel values. If I increase my sample rate to
16000hz, should I also increase my mel channels to 40 as no... Raeldor
MFCC Code Sanity Check0128 (1/27/2011 5:58:25 AM) comp.dsp Hi All,
I have been reading up on MFCC's and written some code based on what
I've been reading. The results kind of make sense, but it's a little
hard to tell. Does anyone here know this stuff well enoug... Raeldor
How do I Calculate Log Energy?8205 (12/17/2010 5:07:03 AM) comp.dsp Hi,
Can someone tell me how to calculate log energy as shown in #7 in the
following document? I thought it was just a total of the log of each
of the 20 log energy values, but this seems to come out the s... Raeldor
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FFT Questions14266 (7/25/2010 4:57:45 AM) comp.dsp Hi Guys,
I want to use FFT for an audio programming project I'm working on and
had some (what are probably quite simple questions). I understand the
concept that FFT converts a time based array of data in... raeldor(34)
Auto-Covariance help729 (3/8/2011 12:42:16 AM) comp.dsp Hi All, I'm trying to calculate the auto co-variance of a 16khz audio signal. The signal has been normalized between -1.0 and 1.0. I am using the following explanation of co-variance to calculate the auto-cov... raeldor(34)
The Theory Behind Why DCT is Used for MFCC Feature Vectors?731 (3/14/2011 5:07:10 AM) comp.dsp Hi All, Does anyone have a good link to the theory behind why DCT is used for MFCC feature vectors? What exactly is it about the DCT values of the mel frequency spectrum that makes it so appealing for voice r... raeldor(34)
FFT and Sine Waves Question3564 (8/26/2011 5:18:59 AM) comp.dsp Hi All, I was doing some experimenting and was wondering if someone could explain my results. I have a pure sine wave at 1000hz generated into a wave file. I also have some FFT code to produce a spectrograph... raeldor(34)
Voice Recognition over Bluetooth534 (8/28/2011 5:35:19 AM) comp.dsp Hi All, I was wondering how voice recognition systems that work over bluetooth cope with the potentially huge difference in the spectogram produced from the source or training samples versus that of a (let's f... raeldor(34)
FFT vs DCT3630 (9/26/2011 2:29:15 PM) comp.dsp Hi All, I'm trying to understand the differences between FFT and DCT and was hoping someone may be able to help me with a couple of questions. 1. Is DCT basically the same as an FFT that operates on real numb... raeldor(34)