Questions tagged [floating-point]
The floating-point tag has no usage guidance.
26
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Efficient Log2 and dB from Floating Point and Fixed Point Representation
Floating point representation encodes a binary number using a mantissa $a$ and exponent $b$ according to $(1+a)\cdot 2^b$, where $a$ is an unsigned fractional fixed point number such that $1\le 1+a &...
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1
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77
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Relationship of ADC resolution and 'lossless' float data type storage
For a given digitised voltage trace, I want to avoid any quantization error introduced via an insufficient precision of the float data type – and at the same time reduce the memory cost. However, I am ...
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Are there now 64-bit processors that deal with denorms routinely with no exception or interrupt?
Title says it all.
Are there processors with FPUs that deal with denorms arithmetically correctly (don't assume they're zero nor flush them to zero) and don't cause an exception? I would be interested ...
2
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3
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366
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Series vs Parallel Biquad Filters
What are the pros and cons of arranging a set of biquad filters in series and parallel? I gather that series should be used in cases where the filters contribute to the same passbands and vice versa ...
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2
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1
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Designing an FIR filter with Gain = 1 on TI DSP processor
I'm trying to design an FIR filter with gain = 1 on DSP processor that does not support floating representation. I'm using MATLAB to design the filter and then transport the taps into my code. The ...
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1
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1
answer
900
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Moving average filter implementation in the floating point [closed]
I have following C++ implementation of the moving average digital filter.
...
- 375
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2
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59
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Why we sometime use some values of fixed point and floating point both in dsp?
I have been writing kernels for a communication dsp device, which uses cmac/cmad operation on fixed and floating point numbers. I am not very clear why both types is used in the same operation.
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2
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3
answers
700
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Implementation of CIC filter using floating point
I am trying to implement a CIC filter and was reading through the literature and found that CIC filter cannot be implemented using floating point. I am unable to understand why that would happen. The ...
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1
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91
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Is multiplying by Ts faster than dividing by fs? [closed]
Say fs = 1000 and Ts = 0.001. Would it be faster to compute Ts at the beginning and subsequently multiply by 0.001 instead of dividing by 1000 when computing frequency-dependent quantities?
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2
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402
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Mitigate floating-point numerical errors for very-low corner frequency low-pass filter with DSP
I'm designing a low-pass filter for a digital signal processing application that ideally just passes a very small bandwidth above DC. I'm using an IIR biquad filter for this, where the coefficients ...
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5
answers
2k
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Single pole IIR filter, fixed point design
We want to do a fixed point implementation of the single pole IIR filter:
$y[n] = a\cdot x[n] + (1 - a)\cdot y[n-1] \quad ;\qquad 0<a<1$
What are the main design considerations to think about ?...
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7
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Why is there no FPU on (most) DSP chips?
Why is there no FPU (Floating Point Unit) on most DSP chips? I found
several answers such as this
one
that explain advantages of fixed point approach such as smaller power
consumption, higher speed ...
- 169
1
vote
0
answers
676
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PSNR calculation with float arrays
The PSNR definition provided by wikipedia is often quoted in discussions regarding PSNR and other similarity metrics.
Essentially the PSNR calculation has two components: the mean squared error and ...
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1
vote
2
answers
856
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Conversion from Floating point representation to Fixed point representation
I have written a matlab function for a constellation mapper and I want to create a Fixed-point version of that code for implementation on FPGA. I know matlab has a specific toolbox for fixed-point ...
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3
votes
1
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3k
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Finding a signal inside another signal
I have a 1D array of 32 bit floating point numbers representing the current draw of a radio operating over a 40 minute span. The number of elements in the array is 29 million and change. There is a ...
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1
vote
2
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103
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Audio Bit Depth "mapping" from DAW to Audio card: is this correct?
Let say I'm generating a 1 kHz sine wave within my DAW, using some synth (Sytrus in my case). I normalize it, so it play at max "digital" amplitude 0db.
Thus, any sample of the signal would gets a ...
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1
vote
2
answers
1k
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Artifacts signal conversion from float to integer
I have a script where i want to change the noise floor to about 96 dB (visual purpose).
The script containing basically a sine wave with after wart do FFT over it.
The script is in python and as ...
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1
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1
answer
567
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How to convert floating point code to fixed point?
I am working on converting a floating point MATLAB code into fixed point C code. The code is to be run on a DSP platform, the specifics of which are yet to be decided.
I'm new to floating point to ...
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1
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50
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Basic question on numerical precision [closed]
I appreciate this opportunity to submit a query on this forum.
When studying the continuous-time & discrete-time distinction, specifically with reference to discrete signals being identical when ...
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2
votes
0
answers
2k
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Applying a FIR filter to floating point array c# [closed]
I have designed using MATLAB a FIR filter with some coefficients.
I have an array that is normalized to -+1. The array is float.
I used this method to apply the FIR to the array but I'm not sure if ...
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1
answer
4k
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Downsampling PCM Audio
I'm looking everywhere for solutions for audio downsampling. However for one reason or another they are incomplete, sometimes buggy, and sometimes are in a programming language I cannot understand.
...
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103
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DSP implementation recommended bibliography (good books-material related to fixed/floating point-optimization) [closed]
I am doing my first steps in embedded systems and there is a big deal of fixed point code and of course DSP optimized code.I would like please if possible to recommend any book/material related to ...
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3
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2
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286
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In image compression using transforms, how to deal with the transformed coefficients as they are not integers?
I am new to the field of image compression. While going through various texts, I read about how transforming the image to another domain using, for example, the wavelet transform, or the DCT, makes it ...
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1
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Understanding Q formats
I have some misunderstandings with Q format. Please help me in understanding this.
If I say Q8 [unsigned] then there will be $8$ fractional bits. Is it ? How can I represent a $1$ and $1.5$ in this ...
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2
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Does it really take 6 minutes and 20 seconds to properly fade-out a single precision audio signal?
Update
This question is purely theoretical and should not account for any psychoacoustic effects, or practical implementations.
Perhaps the question should be rephrased to "How long will it take ...
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1
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How to avoid denormalized numbers?
The same floating-point AMD X86-64 digital signal processing system mentioned in my previous question has a problem where it sometimes slows down substantially when signals attain values very near (...
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