robinsmidsrod

#!ipxe
dhcp
echo Starting Ubuntu x64 installer for ${hostname}
set base-url http://archive.ubuntu.com/ubuntu/dists/lucid/main/installer-amd64/current/images/netboot/ubuntu-installer/amd64
kernel ${base-url}/linux
initrd ${base-url}/initrd.gz
#imgargs linux auto=true url=http://yourserver/some/path/preseed.cfg
boot || 
# If everything failed, give the user some options
echo Boot from ${base-url} failed

xkr47

# input: fullchain.pem and privkey.pem as generated by the "letsencrypt-auto" script when run with
# the "auth" aka "certonly" subcommand

# convert certificate chain + private key to the PKCS#12 file format
openssl pkcs12 -export -out keystore.pkcs12 -in fullchain.pem -inkey privkey.pem

# convert PKCS#12 file into Java keystore format
keytool -importkeystore -srckeystore keystore.pkcs12 -srcstoretype PKCS12 -destkeystore keystore.jks

# don't need the PKCS#12 file anymore

ridencww

/*
 * Simple printf for writing to an Arduino serial port.  Allows specifying Serial..Serial3.
 * 
 * const HardwareSerial&, the serial port to use (Serial..Serial3)
 * const char* fmt, the formatting string followed by the data to be formatted
 * 
 * int d = 65;
 * float f = 123.4567;
 * char* str = "Hello";
 * serial_printf(Serial, "<fmt>", d);

max-mapper

Video stabilization using VidStab and FFMPEG

Examples here use the default settings, see the VidStab readme on GitHub for more advanced instructions.

Here's an example video I made

Install ffmpeg with the vidstab plugin from homebrew

brew install ffmpeg --with-libvidstab

rectalogic

#!/usr/bin/env python
"""
Runs "ip xfrm state" and outputs lines to be added to ~/.wireshark/esp_sa
This process must be run using sudo.

This allows Wireshark to decrypt ipsec traffic captured with 'sudo tcpdump -vni any -U -w /tmp/esp.pcap "ip proto 50"'
"""

import sys
import subprocess

Brainiarc7

Streaming your Linux desktop to Youtube and Twitch via Nvidia's NVENC and VAAPI:

Considerations to take when live streaming:

The following best practice observations apply when using a hardware-based encoder for live streaming to any platform:

1. Set the buffer size (-bufsize:v) equal to the target bitrate (-b:v). You want to ensure that you're encoding in CBR mode.

2. Set up the encoders as shown:

braian87b

# ========================================================
# Setup a Dumb AP, Wired backbone for OpenWRT / LEDE
# ========================================================
# Set lan logical interface as bridge (to allow bridge multiple physical interfaces)
uci set network.lan.type='bridge'
# assign WAN physical interface to LAN (will be available as an additional LAN port now)
uci set network.lan.ifname="$(uci get network.lan.ifname) $(uci get network.wan.ifname)"
uci del network.wan.ifname
# Remove wan logical interface, since we will not need it.
uci del network.wan

Brainiarc7

Build VAAPI with support for VP8/9 decode and encode hardware acceleration on a Skylake validation testbed:

Build platform: Ubuntu 16.04LTS.

First things first:

Install baseline dependencies first

sudo apt-get -y install autoconf automake build-essential libass-dev libtool pkg-config texinfo zlib1g-dev libva-dev cmake mercurial libdrm-dev libvorbis-dev libogg-dev git libx11-dev libperl-dev libpciaccess-dev libpciaccess0 xorg-dev intel-gpu-tools

derpeter

ffmpeg -y -i in.mkv -map 0:v -c:v copy -map 0:a:0 -c:a:0 copy -map 0:a:0 -c:a:0 ac3 out.mkv

derpeter

#!/bin/bash
MIN_SIZE=6G
IN_DIR=.
OUT_DIR=out

find $IN_DIR  -maxdepth 1 -type f -size +$MIN_SIZE -exec ffmpeg -y -i {} -c:v libx264 -preset slow -tune film -profile:v high -level 4.2 -crf 23 -c:a copy -c:s copy $OUT_DIR/{} \;