In one of the previously published posts we already discussed solving a captcha that consists of numbers, i.e., it uses only digits. In this article, we will consider a variant consisting of images with various animals, and the correct value will be one of five (1 out of 5), rotated by 180 degrees.
[maxbutton id="3" text="ZennoPoster" url="/af-zenno" linktitle="External link | External link" window="new" nofollow="true"]
To start working, we need to prepare a database of images; this can be done using a special tool called ZennoPoster. This software allows us to automate our actions, namely: to collect a large number of images used in the captcha in a short time. The essence of the operation is to subsequently select from this collection those photos that are rotated copies of the originals.
Once the sample is ready, we will apply it in practice by uploading it to a real database in .SQL format. This is not a critical step; you can use a regular text file or any other format to save the data.
To avoid wasting extra time on processing the material, we will simultaneously use ZennoPoster: it will automatically convert the image variable values into a hash and then save them to the database table. There will be 2 columns in these tabular data with the names "id" and "hash", where unique row numbers and the hash itself will be stored, respectively.
If you look at the screenshot below, you can see that before removing duplicates from the database, there were approximately 800 rows, and after removing them, there were 500. These values are sufficient for solving the captcha, since there are not many identical images. If you use a different one, you may need a larger sample...
[maxbutton id="3" text="ZennoPoster" url="/af-zenno" linktitle="External link | External link" window="new" nofollow="true"]
Results
What we have at the output: a fully automatic captcha solution, based on our own built database (remember about absolutely any input format for its creation). The script not only guesses the captcha but does so very quickly, and the solving rate is almost 100% (yes, sometimes you will need to manually enter missing data, since we might have missed a couple of images).
https://www.youtube.com/embed/CY9P3fvj3poYou can view this captcha variant using the link below!
[maxbutton id="4" text="Coinpot" url="/af-coinpot" linktitle="External link | External link" window="new" nofollow="true"]
Was this helpful?