This is a living document. Everything in this document is made in good faith of being accurate, but like I just said; we don't yet know everything about what's going on.
Update: I've disabled comments as of 2025-01-26 to avoid everyone having notifications for something a year on if someone wants to suggest a correction. Folks are free to email to suggest corrections still, of course.
| import numpy as np | |
| def wada_snr(wav): | |
| # Direct blind estimation of the SNR of a speech signal. | |
| # | |
| # Paper on WADA SNR: | |
| # http://www.cs.cmu.edu/~robust/Papers/KimSternIS08.pdf | |
| # | |
| # This function was adapted from this matlab code: | |
| # https://labrosa.ee.columbia.edu/projects/snreval/#9 |
Y = a * R + b * G + c * B
Cb = (B - Y) / d
Cr = (R - Y) / e
| BT.601 | BT.709 | BT.2020 | |
|---|---|---|---|
| a | 0.299 | 0.2126 | 0.2627 |
| b | 0.587 | 0.7152 | 0.6780 |
What is strict aliasing? First we will describe what is aliasing and then we can learn what being strict about it means.
In C and C++ aliasing has to do with what expression types we are allowed to access stored values through. In both C and C++ the standard specifies which expression types are allowed to alias which types. The compiler and optimizer are allowed to assume we follow the aliasing rules strictly, hence the term strict aliasing rule. If we attempt to access a value using a type not allowed it is classified as undefined behavior(UB). Once we have undefined behavior all bets are off, the results of our program are no longer reliable.
Unfortunately with strict aliasing violations, we will often obtain the results we expect, leaving the possibility the a future version of a compiler with a new optimization will break code we th
List of oldest supported version of top 10 Linux Distros and their glibc version according to distrowatch.com.
Out of all versions with published EOLs, 2.12 is the oldest glibc still active, found in CentOS 6.8.
If CentOS 6 and 7 are eliminated, the oldest glibc is 2.23 in Ubuntu and Slackware.
| Latency Comparison Numbers (~2012) | |
| ---------------------------------- | |
| L1 cache reference 0.5 ns | |
| Branch mispredict 5 ns | |
| L2 cache reference 7 ns 14x L1 cache | |
| Mutex lock/unlock 25 ns | |
| Main memory reference 100 ns 20x L2 cache, 200x L1 cache | |
| Compress 1K bytes with Zippy 3,000 ns 3 us | |
| Send 1K bytes over 1 Gbps network 10,000 ns 10 us | |
| Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD |
| from flask import Flask, render_template, flash, request | |
| from werkzeug.datastructures import MultiDict | |
| from flaskext.wtf import Form, TextField, TextAreaField, validators | |
| # App config. | |
| DEBUG = True | |
| SECRET_KEY = '87469976308fd14a2d0148247d441f2756b6176a' | |
| app = Flask(__name__) | |
| app.config.from_object(__name__) |
