Hello,
From last response on proosal for Multilingual, usable and effective captchas; i figured out following few solutions to the points raised by the mailing list members:
1)Captcha on the basis of selection of particular object:In this type of captcha the questions will be shown as shown here: https://commons.wikimedia.org/wiki/File:Proposal6correction.png ;other possible questions can be:"Select the images in which man is wearing sunglasses",now problem i encountered while making such captcha request is that a bot could easily use Google images or third eye to find the look for images of man wearing sunglasses from the Wikimedia Commons .....so to encounter this problem we can use a random numbering over the images and then ask user to to select the images in order of numbering for example the only answer to the sample question i provided above is :https://commons.wikimedia.org/wiki/File:Proposal7correction.png ;one of the wrong answer to the given question is:https://commons.wikimedia.org/wiki/File:Proposal8correction.png ; because it is not arranged in correct order which is 1,4,12 (in increasing numeric order).....ps:i did forgot to specify "increasing" numeric order in the question i provided but the plan is to provide the question as "Select human among the given photograph's and select it in increasing numeric order?".
Providing increasing numeric order might make bot guess wrong answer 90% of time,which is quite comparable to the current captcha system that uses OCR as provided in the given algorithm: http://www.gizmag.com/captcha-beating-ai/29559/ .
2)Ask User to click on the same image as provided:The question for this type of captcha looks like this:https://commons.wikimedia.org/wiki/File:Proposal5correction.png we can ask user to click on the options showing equivalent image to that provided in the question.For the question provided the answer is :https://commons.wikimedia.org/wiki/File:Proposal9correction.png .Ps:we ca use more than four options probably eight options since it would be harder of bot to make a guess.
3)For blind and visually impaired users:We can use and audio captcha system which ask user to select the number as it is asked in the audio .For example the visual equivalent of the audio asked by the user will be : https://commons.wikimedia.org/wiki/File:Proposal11correction.png .Now when audio asked user to select number "0" our user will use arrow key to move across different blocks like a slide show....with different voice speaking out the options and pressing enter will select the word spoken....hence verifying that the user is human.....although the above shown image is visual equivalent the actual image visible will be: https://commons.wikimedia.org/wiki/File%3AProposal4correction.png ;....to make the captcha reload we can user to by pressing key "r" which will be instructed in the audio while the captcha starts playing.
Please give your response to idea provided and also the idea is listed here:https://www.mediawiki.org/wiki/Talk:CAPTCHA
Thank You Aalekh Nigam aalekhN https://www.mediawiki.org/wiki/User:AalekhN --