I wanted a way to have a bunch of Morse code mp3s on my mp3 player (with a WPM/speed that I decide and I found an easy way to do it with Linux. Rather than downloading existing mp3s of boring text, I wanted to be able to turn ANY text into Morse code, so I could copy something interesting (perhaps the news? hackaday? bash.org?). It’s a little devious, but my plan is to practice copying Morse code during class when lectures become monotonous. [The guy who teaches infectious diseases is the most boring person I ever met, I learn nothing from class, and on top of that he doesn't allow laptops to be out!] So, here’s what I did in case it helps anyone else out there…

Step 0: GET THE REQUIRED PROGRAMS! Yes, there’s a step zero. Make sure you have installed Python, cwtext, and lame. Now you’re ready to roll!

Step 1: PREPARE SOME TEXT! I went to Wikipedia and copy/pasted an ENTIRE article into a text file called in.txt. Don’t worry about special characters (such as ” and * and #), we’ll fix them with the following python script.

import time
f=open("out.txt")
raw=f.read()
f.close()

cmd  = """echo "TEST" | cwpcm -w 7 | """
cmd += """lame -r -m m -b 8 --resample 8 -q9 - - > text.mp3"""

import os
i=0
for chunk in raw.split("\n")[5:]:
        if chunk.count(" ")>50:
                i+=1
                print "\n\nfile",i, chunk.count(" "), "words\n"
		do = cmd.replace("TEST",chunk).replace("text","%02d"%i)
		print "running:",do,
		time.sleep(1)
		print "\n\nSTART ...",
                os.system(do)
		print "DONE"

Step 2: MAKE MP3s OF THE TEXT! There should be a new file, out.txt, which is cleaned-up nicely. Run the following script to turn every paragraph of text with more than 50 words into an mp3 file…

f=open("out.txt")
raw=f.read()
f.close()
cmd = """echo "TEST" | cwpcm -w 13 | sox -r 44k -u -b 8 -t raw - text.wav"""
cmd+="""; lame --preset phone text.wav text.mp3; rm text.wav"""
import os
i=0
for chunk in raw.split("\n")[5:]:
	if chunk.count(" ")>50:
		i+=1
		print i, chunk.count(" "), "words"
		os.system(cmd.replace("TEST",chunk).replace("text","%02d"%i))

Now you should have a directory filled with mp3 files which you can skip through (or shuffle!) using your handy dandy mp3 player. Note that “-w 13″ means 13 WPM (words per minute). Simply change that number to change the speed.

Good luck with your CW practice!
–Scott (AJ4VD)

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