Cleaning up captcha image (reflected text) - image

I'm struggling with a captcha image that has reflected letters on the bottom. Taking the shadow off the captcha, it can easily be resolved. I have tried using OpenCV, but no success so far. For example, if the captcha text is "h8mb", it will have a reflected shadow with the "h8mb" text cropped as shown below:
I will link the images below, since I can't add them due to the fact that my account is new.
https://i.stack.imgur.com/X7vG4.jpg
https://i.stack.imgur.com/YGufm.jpg
https://i.stack.imgur.com/N3GWB.jpg
https://i.stack.imgur.com/0q7hu.jpg
https://i.stack.imgur.com/yXAWw.jpg
Could someone explain to me how this could be done? Or how could I use OpenCV to do this reflection removal?

As is often the case, the design of this captcha is pretty poor.
Every sample is made of the word struck out, forming a single, largest blob. The other pieces make distinct and smaller blobs, which are too easy to erase by seed filling.

Related

Mosaicking PDF documents?

I have (or, rather, will soon have) a number of maps created in ArcGIS 10.0 and exported as PDF documents. The maps all show contiguous areas, being rather like the pages in a map book. There will also be a smaller-scale map depicting the entire area (let's call it the "study area"), but with less detail, rather like that page of a map atlas that shows what page depicts what area.
I wonder if there is any way to create thumbnails of the larger-scale maps and mosaic them such as to create an index map of the study area. A user would then be able to see, for a particular point on the smaller-scale map, which of the larger-scale maps depicts that part of the study area. (And perhaps see that map by clicking on the larger map?) Does anyone have any ideas I can implement this? I would prefer exporting the maps in PDF format, but, if I can't do all of the above with PDF, then any other format to which a map can be exported from ArcGIS, such as JPG or TIF, will work.
You should be able to create a PDF which does this.
What you need to do is render each page to a small image.
Then collect each of these images and add them as a mosaic to an index page.
Then put links from each small image back to the original PDF page.
If the hierarchy was more than one level deep you could repeat the process.
You need a PDF component to do this. What you want in terms of features is something which does decent PDF rendering. It's an easy thing to do badly and a difficult thing to do well.
ABCpdf .NET does good quality rendering so it's what I would suggest, but then I would because I work on it. :-)

Geoserver and dynamic markers

I am really sorry to post this question, because most likely the solution will be really simple. But I am completely out of search string ideas.
I have a running Geoserver and some custom shapefiles describing buildings etc. I can requesting maps as pngs with the WMS interface and display on a website. So for so good.
In the next step I want to enable the user to specify a coordinate an draw a little marker on the map. This position should not be stored anywhere, I just want to draw it for this user. I am pretty sure this is possible with a WMS request and an inline feature, but I had not any luck finding a working solution and I am out of google search strings.
Please help me before I start drawing overlays over a png map.
You can do this with an inline feature in your SLD - See http://lyceum.massgis.state.ma.us/wiki/doku.php?id=wms:sld:inline_feature for an example.
You can let OpenLayers do the drawing on the client.
Check this example to see how it can be done. It demonstrates how to draw lines, points, and polygons:
http://dev.openlayers.org/releases/OpenLayers-2.10/examples/draw-feature.html

How to easily crop the same image multiple times

I have a set of really big images out of which I need to crop little snippets. These snippets are all exactly the same size but don't follow a strict pattern so I can't do this programatically.
Ideally I would like to open up one of the big files and be able to point and click on say, the top left corner of a snippet and have that automatically be saved to disk without even having to enter a file name, and then continue on with the rest. (Of course this would be the ideal way which I know is probably way off the real possible way!).
I started doing this in Photoshop CS4 but cropping a snippet, saving, undoing (to get to the full image), and starting over again takes way too long.
Maybe someone has a better way to do this in photoshop or in some other software.
Thanks for reading!
Instead of cropping and undoing, you could:
make (or resize) a selection
copy the selection to a new image
save the image
close the image
You might need to split it into two actions, I don't know enough about programming Photoshop.
Thank you everyone for your input.
I ended up doing this with a suggestion a colleague of mine came up with. It consisted of creating a Photoshop "slice" over the first region I wanted to crop and then cloning that region over the rest of the other sections. After that, using Save For Web (and ofter hitting Continue when PS complained about how that image was way beyond Save For Web's capabilities) I could save all images at once.
This was the fastest and easiest method I could find. Until then I was going with Mark Ransom's method.

How to use full-page background image leaving space for binding?

In Latex how can you make the background image to occupy the whole sheet on every page except a certain stripe on the inner side of each page? I can't figure it out.
I have a background image I'd like to be seen in whole on each page after printing/binding.
Matyi
There's some rather scary LaTeX hackery involving putting a picture environment under every page and using \includegraphics to put an image into that environment. You'll have to adjust the size of the image using the width option, and if you want even and odd pages you'll have to check the page number to know whether to shift the image right or left by changing \put(0,0) to \put(3,0) for example.
For page number testing try something on the order of
\ifodd\count0 ...stuff for odd-numbered pages ...
\else ... stuff for even-numbered pages ...
\fi
This isn't really a full answer but will be enough to get you started.
Honestly, I'd just add the white space in the image :)
Well, I was thinking of something like this.
Is this really so rare need to have? I myself need such a thing for the first time now but I don't feel it a so big oddity. It's strange for me that if you want a background to change over even and odd pages, just like normal text do, you need to feel betraying Latex logics. Or maybe I'm too fanatic of this challenge of mine and I want to feel the whole tex world change to fulfill my wishes. :)
Thank you for the answers!

How would you generate default user profile pictures?

I've been admiring StackOverflow's default quilt-like profile pictures (which I notice are also on the Fail Blog) and am curious what program both are using to generate them.
But what I really want to know is: If you were to design the system to create default profile pictures, how would you do it?
I'm looking for ideas on what algorithm you'd use, as well as things like how you would related the image to the user, be it related to their username, or some portrayal of their progress (ie the image gets more complex, or larger, as they gain reputation).
FWIW, the default pictures are generated by gravatar, which is why you'll see them on more than this site.
It's called an Identicon. On Stackoverflow it Gravatar uses your IP address to generate the image.
This is an editorial, not necessarily an answer.
Those auto-generated avatars on this site come from a service (Gravatar) that focuses exclusively on providing avatars and is therefore the core of their business. For apps that aren't specifically intended to generate and display avatars, I would just go with an empty placeholder (like Facebook). It's a neat feature, but is it worth your development time when a simple placeholder would be just as effective?
A very good source of images would be flame fractals. They are rather computationally expensive, so simply sourcing them from a project like electric sheep or having them be rendered by the user's computer should be considered to offload the work.
Who wouldn't want default profile pictures like these?
alt text http://sheepserver.net/v2d6/gen/202/124809/icon.jpg alt text http://sheepserver.net/v2d6/gen/202/124805/icon.jpg alt text http://sheepserver.net/v2d6/gen/202/125373/i77.jpg alt text http://sheepserver.net/v2d6/gen/202/125431/i116.jpg
Use a Julia set or something like that and set the initial conditions to a hash of the user's email address.
I'd use a jpeg server tool (aspjpg or similar) to manipulate the image on load so it displays their badges within their profile pic.
In fact, using any tool to dynamically generate images is pretty cool. Applying some sort of 3d or flash technology to dynamically create images using random variables for eye spacing or facial structure would be pretty wicked as well.
But ya this is a weird question. hah!
I did something similar years back, I used POV-Ray to generate little 3D scenes with torusses (torii ?) and spheres. There were lots of parameters to tweak such as the position, size and colour of each object.
POV-Ray is a scriptable 3D render engine, you can find it here.
Unfortunately my images all looked too similar to each other. I love Gravatar's identicons as uses on this site. I think the symmetry helps and the shapes are unique enough that you can identify users fairly clearly.
In ruby there have a library http://github.com/swdyh/quilt to generate it!

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