Serveral useful recipes for manipulation video with ffmpeg.
Note that a name within angle brancket (like <this>) represents a generic input or output file.
The following recipe extracts the audio from a video file and converts it to WAV format.
ffmpeg -y -hide_banner -i <input> -vn -c …We can use PostScript’s Endpage procedure to e.g. add a signature to each page of a PDF file, using only ghostscript.
In contrast to the earlier article using TeX, this method is suitable for a small annotation that is identical for every page.
This definition of EndPage will …
After some initial experiments with sqlite as a replacement for a json data file format (which I did not pursue in the end), I have now started using sqlite in earnest. And I must say that I quite like it.
At $work, we still have to submit written time sheets …
This document explores how an SQLite database could be used to store data for the resin-calculator. Normally, the recipes are a dictionary keyed to the name of the resin. The value of each recipe is a list of (component, parts-by-weight) tuples. Since a database only contains tables, where each row …
Before the rise of git, I used rcs as my version control system. Because I want to standardize on git, I am slowly converting old repositories.
In this article I’ll be converting my old perl scripts in ~/src/perl.
From the existing repo, we create …
As an engineer I do a lot of calculations. These can be done with pen and paper and a calculator, in an IPython notebook or in a throwaway spreadsheet. All of these methods have shortcomings, though.
Pen and paper is hard to share and (in my case) hard for others …
With leading white space governing the indentation level and so the grouping of statements, Python code already looks relatively clean.
Yet there are additional tools that will help you improve your code.
The pyflakes checker tries very hard to find errors in Python source files. (It does not care …
Sometimes I miss the C’s plain old struct in Python.
Of course Python has dictionaries, but I prefer to write a.b over a['b'].
Here are several ways of doing something akin to a struct in Python.
This is the shortest and most general …