Patrick Roberts

Computer Generate Audio Books

I first tried another text-to-speech program, TextAloud, but the result was too poorly phrased to bear. The program didn't even interpret multiple blank lines as a new paragraph. It would just say the words on both sides of the space without any pause between. Stupid.

via www.mindmaking.info

On the blog for my book, I shared a script that uses speech synthesis to automatically record an audio book from a text file, phrasing and pronouncing it well.

Convert OpenOffice.org Writer / HTML to Kindle

 

The ebookmaker.py that I recently posted now also helps you to publish your book on Kindle. The script makes a zip of a specially formatted HTML file of your book, plus resized images, that you can upload to Amazon's DTP. Judging from the preview of my book, the conversion works well.

Luckily Kindle now supports non-US authors.

Convert OpenOffice.org Writer / HTML to ePub

I found no easy way to make a decent-looking ePub, the standard ebook format, from my book (sadly) composed in OpenOffice.org Writer. Seeing an excuse to stop writing passive prose, to write living code, I sketched a script that makes an ePub from the HTML that Writer exports:

ebookmaker.py

Example: python ebookmaker.py mybook.html

This produces mybook-clean.xhtml -- clean simple HTML of your book that you can paste into your blog or wherever -- and a mybook.epub containing resized images.

The script starts with a table of options to personalize. Those options probably don't yet offer enough control to make the script work perfectly with other books, depending on how the formatting differs from mine, but if you know a little Python and regular expressions, you can adjust the rest.

Do you know a better tool? I tried a few other converters, such as Stanza, but the results were hideous.

Let me know if you use this. It wasn't much fun to write. ePub uses XHTML, which is XML, which, if you can imagine, is the kind of formal language that a herd of UN lawyers would design.

Now that I have my ePub version, do you know any popular sites to share it on?

Simple Secure Remote Backup by E-mail

(Photo: bydo)

mailbak.py - a short command-line Python script. It zips the given files, encrypts the archive with GPG and e-mails it to your preferably large mailbox.

Assembly Line Syntax

It's often convenient to imagine a process as a tree-shaped (or graph-shaped) assembly line. Inputs flow in through the leaves and are transformed, filtered or reduced where branches join. This well represents lazy-functional programming. Say one wants the words from a line-delimited file, excluding acronyms, then converted to lower case and stored in a set for quick lookup. Compare syntaxes...

English:

1. Get every line in file words.
2. Skip empty lines.
3. Strip white space.
4. Filter out words that have every letter capitalized.
5. Covert each word to lowercase.
6. Add to the set.

Procedural:

words = set()
for line in file('words'):
 line = line.strip()
 if line and not line.isupper():
 words.add(line.lower())

Variables describe edges in a graph, connecting parts of code, but without being obvious to the eye. Names are boring to create and are often misspelled.

Lazy-functional using standard Python:

set(imap(str.lower, ifilterfalse(lambda w: w.isupper(), ifilter(None, imap(str.strip, file('words'))))))

Lazy using a Python iterator comprehension:

set(line.strip().lower() for line in file('words') if line.strip() and not line.isupper())

This wastes time on a second strip() call.

Lazy-functional mixed with a Python iterator comprehension:

set(line.lower() for line in ifilter(None, imap(str.strip, file('words'))) if not line.isupper())

This eliminates the second strip() call but has a confusing mix of syntaxes. The data flow repeatedly changes direction.

Prefix syntax - that of Lisp, Python, C, etc. - is backwards: the functions called later must precede those called earlier. One has to say what comes last first, like saying: "Eat a sandwich; make a sandwich; buy groceries." The words are spelled left to right but the sentence is right to left.

Consider this Python syntax hack to write lazy-functional code like an assembly line.

Lazy-functional using pipes.py:

file('words') | pmethod('strip') | pfilter | pnfilter(methodcaller('isupper')) | pmethod('lower') | pset

This isn't shorter, but allows sequences of operations to be written naturally from left to right, without nested and distant parenthesis.

pmethod() eases mapping using a method of the objects to be mapped, making this version more general because it works if the strings are a mix of str and unicode instances. methodcaller() similarly eases filtering.

Presumably, this would be better in Lisp, using its read macros, but this abuse of __ror__ hasn't caused problems yet.

Related: ASPN Cookbook Python recipe, Dataflow programming.

Fancy wxPython Exception Handler

My wxsupportwiz.py module has made it easy to solve most of the bugs that users have found in egoClip. I guess it resembles Mozilla's Quality Feedback Agent, except it doesn't catch crashes in Python extensions, but those are rare.

When an exception goes uncaught, it pops up a little window asking the user if it's okay to send error information to your website. Then it POSTs to your CGI script almost anything you could want about the error:

• exception type
• traceback
• program version
• Windows version
• date
• current directory
• local variables
• and it's easy to add more.

In egoClip's case, the CGI presently just e-mails me everything. The CGI could also match the error details to a set of solutions and output the URL to a page of instructions that the module will popup in the user's webbrowser.

To hook it up, just:

import wxsupportwiz
wxsupportwiz.wxAddExceptHook('http://egofile.com/naughty_users.php')

As usual, let me know if you find this useful or if you have suggestions.