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Sean M. Tracey seanmtracey

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@jboner
jboner / latency.txt
Last active May 28, 2024 18:39
Latency Numbers Every Programmer Should Know
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
@dergachev
dergachev / GIF-Screencast-OSX.md
Last active May 17, 2024 02:53
OS X Screencast to animated GIF

OS X Screencast to animated GIF

This gist shows how to create a GIF screencast using only free OS X tools: QuickTime, ffmpeg, and gifsicle.

Screencapture GIF

Instructions

To capture the video (filesize: 19MB), using the free "QuickTime Player" application:

@mostlygeek
mostlygeek / turing.sed
Created February 20, 2013 08:02
sed is turing complete...
#! /bin/sed -f
#
# turing.sed -- emulate a Turing machine
#
# Christophe Blaess <ccb@club-internet.fr>
# http://perso.club-internet.fr/ccb/
# See text file for information about Turing Machine script.
# Read all the instructions, and add a final newline.
@tracend
tracend / .handlebars.operators.md
Last active April 10, 2024 21:21
Handlebars relational operators #handlebars #helper #cc

Handlebars relational operators

This is a series of MATLAB style relational operators for Handlebars.

Operators

  • eq - equal to
  • ne - not equal to
  • lt - less than
  • gt - greater than
@olasd
olasd / stream_to_youtube.sh
Created March 28, 2014 19:58
Stream video to youtube via ffmpeg
#! /bin/bash
#
# Diffusion youtube avec ffmpeg
# Configurer youtube avec une résolution 720p. La vidéo n'est pas scalée.
VBR="2500k" # Bitrate de la vidéo en sortie
FPS="30" # FPS de la vidéo en sortie
QUAL="medium" # Preset de qualité FFMPEG
YOUTUBE_URL="rtmp://a.rtmp.youtube.com/live2" # URL de base RTMP youtube
@savvot
savvot / ffmpeg-extract-keyframes.sh
Last active February 3, 2022 06:40
Extract only keyframes (I-frames) from video to images with console ffmpeg
ffmpeg -ss <start_time> -i video.mp4 -t <duration> -q:v 2 -vf select="eq(pict_type\,PICT_TYPE_I)" -vsync 0 frame%03d.jpg
@mondain
mondain / public-stun-list.txt
Last active May 28, 2024 17:22
Public STUN server list
23.21.150.121:3478
iphone-stun.strato-iphone.de:3478
numb.viagenie.ca:3478
s1.taraba.net:3478
s2.taraba.net:3478
stun.12connect.com:3478
stun.12voip.com:3478
stun.1und1.de:3478
stun.2talk.co.nz:3478
stun.2talk.com:3478
@blacklee
blacklee / ffmpeg-to-480p.sh
Created February 19, 2016 13:43
ffmpeg convert video to 480p
ffmpeg -i input.mp4 -s hd480 -c:v libx264 -crf 23 -c:a aac -strict -2 output.mp4
@sagivo
sagivo / gist:3a4b2f2c7ac6e1b5267c2f1f59ac6c6b
Last active May 20, 2024 15:38
webRTC stun / turn server list
to check if the server works - https://webrtc.github.io/samples/src/content/peerconnection/trickle-ice
stun:
stun.l.google.com:19302,
stun1.l.google.com:19302,
stun2.l.google.com:19302,
stun3.l.google.com:19302,
stun4.l.google.com:19302,
stun.ekiga.net,
stun.ideasip.com,
@epiphone
epiphone / installing-openwhisk-on-ubuntu.md
Created January 24, 2017 13:24
Installing OpenWhisk on Ubuntu Server 16.04

Configuring the OpenWhisk server

This guide contains instructions on manually setting up Openwhisk and CouchDB on a fresh Ubuntu 16.04 server.

The guide is based on the OpenWhisk Ansible README, which at the time of writing is missing some key steps and gotchas - hence this new guide.

1. Dependencies

sudo apt-get update