I am creating a data entry web application using phpOCR. Where user need to put the numbers that will show on image. In that purpose I am using phpOCR, but it only detect the numbers that is very clean, but I need to detect the numbers that is blur on the image.
The below image is an example of my images, where phpOCR detects only the numbers in red, not the blur numbers.
On the below image the blur number is 10-30-60.
Is there any way to solve this?
You might be able to drastically change the contrast and brightness of the image - then, possibly, those faint letters will become black, and the background completely white. The OCR may then be able to read it. But then, some things may just not be possible for the OCR to detect.
Related
Overview:
I am working on a video creation project. The technology I am using are: imageMagick, php, ffmpeg.
Current Status:
Currently the project is able to create videos using images and texts and few basic transitions. The way I am doing it is using imagemagick to create gif using input images(with transition effects in them) and then converting all gifs to videos and atlast concatenating the video together.
Next Move (My question):
I am now set to take it to the next level. So, what I am having is a video(1920x1080) with some white frames(1280x720) that keeps shifting in each frame. I want to replace those white frames appearing in some frames of the video with some images(1280x720) that I wish to use. Please see the image here and you will get an idea: These are just two frames from my video. If you can see carefully the images are shifting(white space is not constant).
Expectation:
So, I want to fill those white space with one of my own image. If the case would have been for only one frame I could have used ffmpeg to overlay image on the exact width and height. But here the white space is not fixed and keeps shifting in all the frames and there are a lot of frames. So, I am looking for something like opencv or some other technology that can be used for object detection in a video or in a set of frames and replace the detected area with some other image.
I just need a kick. So, if anyone has already worked on something like this just suggest me what technology can I use. Thanks in advance.
It all depends on exactly what you can assume :
If you can safely assume that your rectangle's boundary is never occluded (hidden) somehow, you can try finding the edges in your image (like OpenCV's Canny edge) and then look for rectangular shape (corners forming a warped rectangle, or the very popular Hough Lines).
If the rectangle you're looking for is always white, you can threshold the image in a colorspace like HSV to look for maximum value (the V in HSV ~ brightness) then rectangular shape search in a binary image.
If your corners are occluded sometimes you'll have to do some tweaking with your image, like morphological operations ("grow and contract" binary thresholded image), then Hough Lines could do the trick.
Note that this answer assumes that once you know where the rectangle is, "you're done", and you just have to overwrite the rectangle with custom content.
I also do not check for any time-continuity : you video frame might jump around based on the frame-by-frame appearance of rectangle. You'd have to include some knowledge about previous positions.
I've created my own algorithm to remove artifacts based on pixels. The only problem is that I have to manually specify the range of RGB based on a picture.
I'm trying to make it a bit more automatic, and have concluded that artifacts are usually very light colored and barely visible unless tilting the screen. Is there any RGB math that I can use to weed these artifacts out properly?
A basic way to do this is to use an adaptive blur on the image. Very close to white will be turned white, and so on, but edges will stay intact. Use ImageMagick, http://www.php.net/manual/en/imagick.adaptiveblurimage.php
I need to create a PNG radial gradient with opacity. I've looked through GDLib but I can't see a way to generate radial gradients. Does anyone know of a way with GDlib or any other graphics library for PHP?
I suppose worst-case I could generate it pixel-by-pixel using GDLib but how does one even start to do the math on that?
The goal is to generate sexy lighting effect background PNGs for web pages. An example of the effect can be seen on the header here which uses this background image. I've tried generic white lighting effect PNGs but it doesn't look anywhere near as good as tinted lighting, so my generated PNGs will take into account the website's color scheme.
I assume server-side is the way to go because browser support for CSS radial gradients is so patchy.
Why not use a combination of imagecolorallocatealpha() and imageellipse() or imagefilledellipse()?
Edit:
See this class for an example of what I mean. You should be able to extend this to support alpha.
Edit2:
I have made some modifications to the class above to yield alpha support. It's not perfect, but it works for ellipses and such:
http://codepad.org/1eZ3Km0J
the classic video game trick is to apply a gradient texture, rather than compute the light. this is a perfect use for the technique.
make a grayscale gradient at a large-ish pixel dimension (2048px square is common) and several smaller ones (1024,512,256px etc) pick the closest one for your need (scaling up may exaggerate banding, scaling down may introduce moire).
use php gd function such as imagecopymerge. depending on intent, you could store the result on first use.
I suppose worst-case I could generate
it pixel-by-pixel using GDLib but how
does one even start to do the math on
that?
The math is easy, alpha = max_alpha - (distance_to_center / radius) where the distance is Euclidean, i.e. sqrt( (x1-x2)^2 + (y1-y2)^2 ).
I am looking to automate a process of:
Taking text from a csv and using the value as text for a css button.
Capturing that HTML and cropping it so the whitespace is not included
Saving the captured button
Steps 1 and 3 are trivial but the problem comes in at step 2. Does anyone know how to take a "screenshot" that targets a specific area of the screen not using co-ordinates or width and height? The images will be variable in width.
I was thinking perhaps it could be based on colour? If a certain colour is encountered at both X and Y then we have an area.
I'm guess your trying to get images out of this so the best thing I can think of is to use GD or imgmagik to generate them and forget the css or maybe you have a mac an photoshop and can write an applescript to automate the process
I was wondering if it was possible if I had an image like:
I would be able to change certain parts of the images colors. For example if I wanted the bow green and the present red with yellow stripes, would I have to make a new image that had that or is there a way to program something (elegantly) along the lines of that? I'm just asking to see if its possible and if it is, what language would be best to do this?
Keep in mind this would be a feature on a website.
That's not going to be easy the way the image is. You have no way to tell the computer which part is the bow, which part is the stripes, and which part is the box. However, if you pre-colored them, you could do a color replace using GD library or imagemagick pretty easily. You'd do this in PHP. Here are some examples of how you could do it, I'd personally go the imagemagick route.
How can I replace one color with another in a png 24 alpha transparent image with GD
http://www.imagemagick.org/Usage/color_basics/#replace
(this example even has a similar gift box as the usage case, hehe)
Try leaving the parts you want changable transparent. Then, give the div it's in a hover state with the second background color.
You could:
Use an indexed-color image and change the colors in the palette.
Use #MT's suggestion, though it kinda gets out of hand with multiple colors and jagged regions.
Pick control points and fill ("floodfill") the image through them - programmatic version of using the bucket tool.
Use #profitphp's suggestion, which is really better my last one.
Abandon compatibility and use the new canvas element while it still has the "cool" factor :)
i presume this is a web-based painting application; you'll require a human to tell you what the parts are, and where they want the coloring to be.
The issue then becomes how to perform a flood fill at the user's request.
The best i can suggest is perform the flood fill server-side, using an image processing library - handing back the image to the user:
There is no javascript ability to access pixel data of an image.
Edit: Performing flood fill with HTML Canvas