Upgrade Captcha to allow sound playback

I think that using and depending on proprietary services is not a good idea.

A better solution would be to use eSpeak or other speech synthesizer to generate WAV files and link them in the page as it is done for images. They can even be compressed to Ogg Vorbis or other format, since theoretically they will be small enough and the process will not take too much time. Here are some examples:

$ time (espeak -s 130 "1, 2, 3, 4, 5" -w captcha.wav && oggenc captcha.wav -o captcha.ogg)
Opening with wav module: WAV file reader
Encoding "captcha.wav" to
"captcha.ogg"
at quality 3,00
[ 80,0%] [ 0m00s remaining] \

Done encoding file "captcha.ogg"

File length: 0m 04,0s
Elapsed time: 0m 00,0s
Rate: 98,5333
Average bitrate: 26,9 kb/s

real 0m0.072s
user 0m0.030s
sys 0m0.010s

$ du -b captcha.*
17066 captcha.ogg
179158 captcha.wav

$ time espeak -s 130 "1, 2, 3, 4, 5" --stdout | oggenc - -o captcha.ogg
Opening with wav module: WAV file reader
Encoding standard input to
"captcha.ogg"
at quality 3,00
[ 0,0%] [12m08s remaining] \

Done encoding file "captcha.ogg"

File length: 0m 04,0s
Elapsed time: 0m 00,1s
Rate: 74,4404
Average bitrate: 26,9 kb/s

real 0m0.066s
user 0m0.040s
sys 0m0.000s

Probably it can be optimized more by adjusting the sample rate and the quality. The audio files can even be generated in different languages by the -v option.

You are correct. I did not actually think about that.

There is an alternative for this CMS which we could use instead: http://drupal.org/project/captcha_pack

Some of the word/phrase-based ones might be hard for non-English speakers. So the math-based captcha would probably be the best from that list. It should be possible to configure it to not be too easily crackable by bots.

Changed the captcha to a math one. Hope this helps with spam too

Automatically closed -- issue fixed for 2 weeks with no activity.