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How to Add a Watermark to Video

FFMPEG filters provide a powerful way to programmatically enhance or alter videos, and it’s fairly simple to add a watermark to a video using the overlay filter. The easiest way to install ffmpeg is to download a pre-built binary for your specific platform. Then you don’t have to worry about including and installing all the right dependencies and codecs you will be using.

Once you have ffmpeg installed, adding a watermark is as easy as passing your existing source through an overlay filter like so:

ffmpeg -i test.mp4 -i watermark.png -filter_complex "overlay=10:10" test1.mp4

Basically, we’re passing in the original video, and an overlay image as inputs, then passing it through the filter, and saving the output as test1.mp4.

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import unittest
from contextlib import contextmanager


class TestCase(unittes.TestCase):

    @contextmanager
    def assertNotRaises(self, exc_type):
        try:
            yield None

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This is an unofficial manual for the couchdb Python module I wish I had had.

Installation

pip install couchdb

Importing the module

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on El Capitan, after installing the brew...

$ brew update
$ brew tap caskroom/cask
$ brew install Caskroom/cask/java

And Java 8 will be installed at /Library/Java/JavaVirtualMachines/jdk1.8.xxx.jdk/

Check version:

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import asyncio
import injections
import aiopg.sa
from aiohttp import web


@injections.has
class SiteHandler:

    # this is only place holder, actual connection

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Javascript

Javascript is a programming language that started out being the main language to "code" the web. It is used to build web apps and websites alongside HTML and CSS. However, it can now also be used to build server-side, desktop and hybrid mobile apps. Heck, it can even be used to program Arduino microcontroller boards!

• Eloquent Javascript by Marijn Haverbeke
• Javascript: The Good Parts by Douglas Crockford
• The Principles of Object Oriented Javascript by Nicholas Zakas
• Programming Javascript Applications by Eric Elliot
• Speaking Javascript by Axel Rauschmayer
• Javascript Enlightenment by Code Lindley
• You Don't Know JS (series) by Kyle Simpson

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Latency Comparison Numbers
--------------------------
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

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function logClass(target: any) {
 
  // save a reference to the original constructor
  var original = target;
 
  // a utility function to generate instances of a class
  function construct(constructor, args) {
    var c : any = function () {
      return constructor.apply(this, args);
    }

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function logClass(target: any) {
 
  // save a reference to the original constructor
  var original = target;
 
  // a utility function to generate instances of a class
  function construct(constructor, args) {
    var c : any = function () {
      return constructor.apply(this, args);
    }

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Studying for a Tech Interview Sucks, so Here's a Cheat Sheet to Help

This list is meant to be a both a quick guide and reference for further research into these topics. It's basically a summary of that comp sci course you never took or forgot about, so there's no way it can cover everything in depth. It also will be available as a gist on Github for everyone to edit and add to.

Data Structure Basics

###Array ####Definition:

• Stores data elements based on an sequential, most commonly 0 based, index.
• Based on tuples from set theory.