| Andrew Cooke | Contents | Latest | RSS | Twitter | Previous | Next

C[omp]ute

Welcome to my blog, which was once a mailing list of the same name and is still generated by mail. Please reply via the "comment" links.

Always interested in offers/projects/new ideas. Eclectic experience in fields like: numerical computing; Python web; Java enterprise; functional languages; GPGPU; SQL databases; etc. Based in Santiago, Chile; telecommute worldwide. CV; email.

Personal Projects

Lepl parser for Python.

Colorless Green.

Photography around Santiago.

SVG experiment.

Professional Portfolio

Calibration of seismometers.

Data access via web services.

Cache rewrite.

Extending OpenSSH.

Last 100 entries

Mapa de Ciclovias en Santiago; How Unreliable is UDP?; SE Santiago 20m Bike Route; Cameron's Rap; Configuring libxml with Eclipse; Reducing Combinatorial Complexity With Occam - AI; Sentidos Comunes (Chilean Online Magazine); Hilary Mantel: The Assassination of Margaret Thatcher - August 6th 1983; NSA Interceptng Gmail During Delivery; General IIR Filters; What's happening with Scala?; Interesting (But Largely Illegible) Typeface; Retiring Essentialism; Poorest in UK, Poorest in N Europe; I Want To Be A Redneck!; Reverse Racism; The Lost Art Of Nomography; IBM Data Center (Photo); Interesting Account Of Gamma Hack; The Most Interesting Audiophile In The World; How did the first world war actually end?; Ky - Restaurant Santiago; The Black Dork Lives!; The UN Requires Unaninmous Decisions; LPIR - Steganography in Practice; How I Am 6; Clear Explanation of Verizon / Level 3 / Netflix; Teenage Girls; Formalising NSA Attacks; Switching Brakes (Tektro Hydraulic); Naim NAP 100 (Power Amp); AKG 550 First Impressions; Facebook manipulates emotions (no really); Map Reduce "No Longer Used" At Google; Removing RAID metadata; New Bike (Good Bike Shop, Santiago Chile); Removing APE Tags in Linux; Compiling Python 3.0 With GCC 4.8; Maven is Amazing; Generating Docs from a GitHub Wiki; Modular Shelves; Bash Best Practices; Good Emergency Gasfiter (Santiago, Chile); Readings in Recent Architecture; Roger Casement; Integrated Information Theory (Or Not); Possibly undefined macro AC_ENABLE_SHARED; Update on Charges; Sunburst Visualisation; Spectral Embeddings (Distances -> Coordinates); Introduction to Causality; Filtering To Help Colour-Blindness; ASUS 1015E-DS02 Too; Ready Player One; Writing Clear, Fast Julia Code; List of LatAm Novels; Running (for women); Building a Jenkins Plugin and a Jar (for Command Line use); Headphone Test Recordings; Causal Consistency; The Quest for Randomness; Chat Wars; Real-life Financial Co Without ACID Database...; Flexible Muscle-Based Locomotion for Bipedal Creatures; SQL Performance Explained; The Little Manual of API Design; Multiple Word Sizes; CRC - Next Steps; FizzBuzz; Update on CRCs; Decent Links / Discussion Community; Automated Reasoning About LLVM Optimizations and Undefined Behavior; A Painless Guide To CRC Error Detection Algorithms; Tests in Julia; Dave Eggers: what's so funny about peace, love and Starship?; Cello - High Level C Programming; autoreconf needs tar; Will Self Goes To Heathrow; Top 5 BioInformatics Papers; Vasovagal Response; Good Food in Vina; Chilean Drug Criminals Use Subsitution Cipher; Adrenaline; Stiglitz on the Impact of Technology; Why Not; How I Am 5; Lenovo X240 OpenSuse 13.1; NSA and GCHQ - Psychological Trolls; Finite Fields in Julia (Defining Your Own Number Type); Julian Assange; Starting Qemu on OpenSuse; Noisy GAs/TMs; Venezuela; Reinstalling GRUB with EFI; Instructions For Disabling KDE Indexing; Evolving Speakers; Changing Salt Size in Simple Crypt 3.0.0; Logarithmic Map (Moved); More Info; Words Found in Voynich Manuscript; An Inventory Of 3D Space-Filling Curves

© 2006-2013 Andrew Cooke (site) / post authors (content).

Script to convert WMA to MP3 on Linux

From: "andrew cooke" <andrew@...>

Date: Thu, 1 Jan 2009 13:03:51 -0300 (CLST)

This simply uncompresses the wma file and then re-encodes it as mp3.  It
uses a fifo rather than a temporary file to avoid writing to disk (much
faster than the temporary file approach, but the uncompressed intermediate
file is big).

It's difficult to know what quality setting to use - since the wma file
was already compressed, anything other than "perfect" is going to lose
even more information.  On the other hand, there's no point in using crazy
quality if the details have already been thrown away.  So I just opted for
variable bit rate and let the encoder decide.

Typical results have similar file sizes in some quick tests I made, but
one file was ten times bigger as an mp3.  I don't know why.

This is based on the scripts at the link given below; I just reformatted,
fixed options that had changed slightly, and used vbr.

Note that mplayer will require appropriate codecs.  For me that meant that
the ffmpeg library was needed.

#!/bin/bash

# Dump wma to mp3
# from http://ocaoimh.ie/2005/08/16/how-to-convert-from-wma-to-mp3/

for src in *.wma
do
  if [ -f "$src" ]
  then
    fifo=`echo "$src"|sed -e 's/wma$/wav/'`
    rm -f "$fifo"
    mkfifo "$fifo"
    mplayer -vo null -vc dummy -af resample=44100 -ao pcm:waveheader
"$src" -ao pcm:file="$fifo" &
    dest=`echo "$src"|sed -e 's/wma$/mp3/'`
    lame --vbr-new "$fifo" "$dest"
    rm -f "$fifo"
  fi
done

Single Line

From: andrew cooke <andrew@...>

Date: Sun, 4 Oct 2009 08:45:18 -0400

One line above was split across multiple lines.  The text below should
work woth cut + paste.

Andrew

#!/bin/bash

# Dump wma to mp3
# from http://ocaoimh.ie/2005/08/16/how-to-convert-from-wma-to-mp3/

for src in *.wma
do
  if [ -f "$src" ]
  then
    fifo=`echo "$src"|sed -e 's/wma$/wav/'`
    rm -f "$fifo"
    mkfifo "$fifo"
    mplayer -vo null -vc dummy -af resample=44100 -ao pcm:waveheader \
"$src" -ao pcm:file="$fifo" &
    dest=`echo "$src"|sed -e 's/wma$/mp3/'`
    lame --vbr-new "$fifo" "$dest"
    rm -f "$fifo"
  fi
done

Shorter variant, using Bash redirections...

From: Jason Dusek <jason.dusek@...>

Date: Wed, 21 Sep 2011 04:01:34 +0000

#!/bin/bash
set -o nounset -o errexit -o pipefail
# Dump wma to mp3
# from http://ocaoimh.ie/2005/08/16/how-to-convert-from-wma-to-mp3/
for src in *.wma
do
  if [[ -f "$src" ]]
  then
    mplayer "$src" -vo null -vc dummy -af resample=44100 \
            -ao pcm:waveheader \
            -ao pcm:file=>(lame --vbr-new - "${src%wma}"mp3)
  fi
done

Comment on this post