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Detection of defacts during video rendering ( which algorithm to use)

I would like the system to pin point/highlight the deformed area to the user during video rendering. Lets say currently I have an image with a list of squares as shown in the image below, this is the original image without defects.
In the following image, is the sample image that consist of a defect, whereby there is an extra line in between the squares.
I would like to have something as shown in the sample image below where by it will have a red square to highlight the "extra line" to inform the user that there is a defect and will pin point the defect to the user.
The defects may appear in any kinds of shapes or forms, and I would like to pin point the defects to the user. So what kind of algorithm I should use in order to achieve this?
Also, is machine learning required in order to achieve this?
Currently I am using Emgucv in C#, but I am not sure what algorithm I should use that can achieve this. Any suggestions are appreciated.
Thank you.

You could just to an cv::absdiff to find the changed areas. After that, use findcontours to group the defects and draw an outline around them.

Image OCR - Filtering unwanted data

Basically I'm reading vehicle license plates using tessract OCR, however despite being able to emphasise text easily enough via changing contrast, reducing noise an so on, some 'parts' of the vehicle remain on the image which does cause the OCR to throw bad results.
For example take:
I can change this easily enough, such as:
I'm looking to eliminate the edges off each plate, here's another example:
I could remove the edges using pixel manipulation algorithm, however I don't feel it's the right method, and would cause quite a lot of problems.
I've been using the following application to test various methods such as morphology and eliminating the unwanted data, so far I haven't been successful.
http://www.codeproject.com/KB/GDI-plus/Image_Processing_Lab.aspx
However someone with knowledge of this could use the application on the article above to achieve want I'm trying, so feel free to give it a try.
Thanks

Please try to use stroke width transformation concept.
This concept use to segment text from natural images.....

I already did such an algorithm. I just can say that it works great. The secret is, that you need to know that the light is coming just from one side perhaps. You cannot set the image to "black/white" just by using ONE threshold.
Detect the average luminance of parts of the image and use this luminance calculation to set the threshold for each region.
For example, if the left top is lighter, you need a lower threshold to make these parts not to bright. And if the bottom right has low light, you need to set the threshold higher to receive all existing light information.
Then, you need just to drive into the image from each side by using the method:
IsPixelAboveThreshold ?
If it is below, you are on the border, if it is above, you can say you are on the middle of the image with more brightness.
Regards

wpf custom control: audiowaveform rectangle with selection slider

I'm working on a c# wpf app in which I want to do something with audio. the irrklang audio library provides me with a pcm decoded 16 bit byte array.
I want to create a timeline control which shows the waveform along the timeline with an overlaying rectangle which the user can drag and click/drag the left and right side to increase or decrease the selection.
It is used to the trim the audio track. I would like the selected min and max to be databindable, the minimum and maximum value of the total track to be bindable.
To clarify here is an image mockup:
I'm not asking for a complete control but tips and suggestions on how to tackle this are more than welcome. Perhaps solutions like this already exist but so far I haven't been able to find it.
I think I need to tackle: the control (zooming, panning and changing the selection) and drawing the waveform in the control
Thanks in advance,

I think you should check out this codeplex project
http://wpfsvl.codeplex.com/

Refer to Audio WaveForm Drawing Using WPF.
Something based upon WaveFileTrimmerControl.xaml would be useful, it uses related controls PolygonWaveFormControl.xaml & RangeSelectionControl.xaml (links are to the XAML but refer to the CS also). In any case it'd be a good starting point for building a control that exactly meets what you want.
You could override the render method and use primitives which will give possibly better performance; but like anything related to performance I'd try the above approach first which is almost certainly good enough.

Overlaying a 'dot' on to an image on click

I am trying to write a simple program that lets me overlay a dot on top of an image when the image is clicked. I can save the X and Y data back to my database but then I will want to be able to call that information back at a later date and overlay the dots again via code unlike the first time when the user had to click the image.
I got as far as capturing the X and Y of the click no problem but I am having trouble finding examples specifically for what I am trying to do. All of the examples online seem to be for saving the image with the added graphic but I do not need to do that as it will be the same image every time.
Once I can do this, I also need to work out a way that I can detect what area of the image has been clicked. The areas I need to mark out vary in shape and size so I need to try and work out a way to 'map' these areas and then cross reference with the co-ordinates of the users click (I assume that I may need to do some clever geometry stuff for that?)
If anyone has any suggestions of what subjects/classes/methods etc. to research for either of my queries, I would very grateful.
Thanks in advance

You can use the System.Drawing namespace to achieve this.
Create a control and override OnPaint and OnPaintBackground. Store your clicks in a List
In OnPaintBackground, draw the image using DrawImageUnscaled using the graphics object which is passed to you as a parameter.
In OnPaint, loop through your points array and call graphics.FillElipse or similar to draw a little dot.
Because this isnt a retained mode graphics system, you need to keep drawing these items so this may not suit a large number of dots. In that case, you can create an in memory bitmap and get a graphics drawing object using graphics.FromImage.

How can i crop image using C#

I have a picture of document taken from camera.
Now what i have to do is crop only document from that image .
Please can anyone suggest me how best it can be done or first is it possible or not
Edit
For more information .. my next question
How to get edge coordinates of a image?

If you know the area that contains the image data you would like to crop, you could use this article from MSDN:
http://msdn.microsoft.com/en-us/library/ms752345.aspx
If you need to find the relevant area before cropping, you need to investigate some image processing techniques. e.g. Corner Detection

In the assumption you are performing preprocessing for OCR, I would look into using the Aforge Framework if possible.
There is a specific set of functions in the Imaging classes for preforming crops and any other related manipulations(image rotation, hue adjustment, brightness/contrast adjustment, filter noise, etc) that you might need.

Two links for you
http://google.com/search?q=c%23+crop+bitmap and http://www.nerdydork.com/crop-an-image-bitmap-in-c-or-vbnet.html