I have implemented a business card reader image using ocr api by follow the link/ tutorial
http://tinsuke.wordpress.com/2011/11/01/how-to-compile-and-use-tesseract-3-01-on-ios-sdk-5/
It can scan the text of some screen shots of UIalert views / table views. and some images having text like follows.
Can recognize text on this image:
[Airoplane mode wi-fi vpn ratch data sounds brightness general wall paper]
but when i capture business card it returns some special charecters and numbers. some times recognized if it is very very clear and big text in captured image.
Can NOT recognize text on follow like images
[ xas $- 432 *7 5$#2 $###%^ ^&* I( WQ#$ follow like√ √dg # ]
why how to resolve this issue.
Tesseract library is open source library. I don't think it is that much accurate.OCR gives best results for image more than 150 px resolution with black and white image .The image which you are capture with the camera of iPad or iPhone is saved with 72px that tesseract cannot give best results.If you are more interested then there are some paid libraries with good accuracy you can try out some :here
Related
I've used a resizing program to resize my image to the requisite 100 by 155 pixel dimensions for the banner image; but when I upload it I get an error message saying there's something wrong with the dimensions. The image I'm uploading is a stock photo I've purchased and have full rights to, meaning it's not home made. Any idea what else the problem could be. The program im using is pretty old and standard. Is there a specific one that can be recommended that is straightforward and won't give me an error on the facebook details page?
Sorry for misunderstanding,
Check out these instructions here:
https://developers.facebook.com/docs/guides/appcenter/#uploading
Especially those:
Don't put logos and text against the border of images.
Make sure banner images fill out the frame completely (and that they leave no white space, no rounded edges or no borders).
Round the edges of icons. We recommend that you use transparency and PNG, not GIF.
If your problem persist, Try another program. Personally, I use Adobe photoshop (Actions) to generate all graphics for my facebook apps, also there's tons of other programs that can help.
If you mean facebook cover Photo by banner image then the optimal size for it is 851px by 315px.
Here you'll find a quick Reference for Facebook Timeline Image Sizes:
http://laurenproctor32.com/tag/facebook-image-size/
Have a nice day.
I want to integrate OCR in an iOS application. I have found some helpful tutorials, specially This Article: How To: Compile and Use Tesseract (3.01) on iOS (SDK 5), helped me a lot. Now I can read plain text from any image which has a clear background. But I want to read information from an ID card which doesn't have clear background at all!
I have also found some answers regarding removing background in stackoverflow, for example: Prepare complex image for OCR, Remove Background Color or Texture Before OCR Processing and How to use OpenCV to remove non text areas from a business card?
But those solutions are not for iOS. I understand the steps, but I need an iOS example and if it is using Core Image, than it would be better for me.
I have no problem in OCR end, but my problem is to remove the background.
Initial Image:
After removing, the image should look like this:
Can you refer me an iOS example? or Is it possible to refer me an iOS example to remove all the color without Black color?
the best way to detect a card in sence is traing a cascade classifier.
Training is not a very small project. the count of the sample images should be more thank 10K.
Once you get the trained cascade classifier, you can detect the the card quickly.
The detection is very quick on iOS, but the tesseract recognition is not very fast,
I am doing my own OS(from scratch) which is not based on any pre-existing kernels or OS. So i know screen is divided into 80*25 and i know that usually it is like 0xB8000 can hold a attributes of character in 0xB8001 and i know only that much.
But how to display an image on screen pixel by pixel? how do i address each pixel and send the data(colour)?
Currently i am printing text on screen using 0xB8000. so if i address 0xB8000 am i adressing a pixel?
I am not at all clear in this aspect. so pls help.
please note that i am not using and i can't use any graphic libraries or so because i'm building my own OS from scratch.
I want to do this in C even though i know assembly
80x25 is so called "text mode", that is a byte in memory corresponds to a character on the monitor. You normally switch video adapter into "graphics mode" and you have pixel space.
You can start your reading from here: CGA - Standard Text Modes.
I have an image in UIImageView. Those images are generally of clothes or accessories captured from camera on plain backgrounds. Now, I have to give a functionality to users so that they can remove the background from the actual image which is being shown. Something like what is shown in the picture here. As the slider will move the background will start getting removed more and more. Something like the 'instant alpha' brush in the Preview application available in Mac OS X. I wish to do this in native iPhone app.
I know I'll require some algorithm for image processing to do this. Does anyone have anything helpful which I can refer or use in order to get this done? Thank you so much in advance.
You can render your image in some context, than change all points you need to the color you want, get image from your context and display it again.
This link should help you to get color of a pixel in context.
Note, that this method is too slow, so I think you should remember all positions of pixels you
need to change to make your app a bit faster.
We're using the facebook graph API http://developers.facebook.com/docs/reference/api/post/ and adding the picture parameter. Our picture is a 30x30 pixel image, which is exactly the size we want for the facebook web version. However, the image will be pixelated when using the FB mobile app on an iPhone4 (retina display).
Is there any way to serve a 60x60 high resolution image, but render it always at 30x30 for facebook wall posts?
Well.. as of this moment, here is what I have found out, and offer a 'solution' that has worked for me based on the time i've had to test & play with this concept. For all the readers out there, who need a quick answer to the question, i don't have the exact solution to the question, but…. Essentially, your 30x30 image is being scaled to 90x90. The 60x60 image is being scaled to 90x90. And I can not find a way to go around this.
Below is what I have tried. Feel free to add input.
Take your feed image, and stroke a 2-5px black line around the frame of the image.
Load up your app, initiate a wall feed on the device. With the image present, take a screenshot. Mail yourself the image. Open it up in Photoshop (or photo editing program). Use a Marquee tool to outline the image. Cut it out of the screenshot and paste it as a new image. What size is it? 90x90, right? (and obviously 180x180 if image is retina)
Create a 90x 90 image. Copy your original 30x30 image and paste it anywhere you want within the new 90x90 images' frame. Upload it to the URL parameter's location. Re-run your app. By re-running it, i mean you have to shut it down completely, it appears as though the SDK is cacheing the image upon first launch of the feed and you can clear that cache by closing the app completely, and rerunning it. When you do, you will see significant improvements with the look of the image. It may not be a retina image, but it at least won't be 'fuzzy ugly'. At this point, it boils down to how nice of illustrative lines that where done in the design process to remove the aliasing effect produced from the conversion to a raster graphic. As well, i'm not sure if a variation of resampling method will produce even better results.
Some things i've tried:
I've also saved it as a png file with no transparency : 144ppi at 90 x 90 size. In other words, save your 90x90 image with a higher resolution (pixels per inch). Remember to not constrain proportions as you image resize. And note that If you are using adobe products, i.e. photoshop ) - don't save for web, just use 'save as…', as this will retain the ppi you specified. Although, i don't believe i see much of a difference in the quality which this is displayed going this route, and best to try to keep the file size down as this will increase the overall image size by about 500% or more.
I've tried variations of hosting the image twice the size (180x180) within the same hosted folder and naming it image#2x.png & image-large.png <--(just for the heck of it). This is not really solving the problem either.
Some other things I have not tried:
Monitoring your web server traffic, and any "not found" errors to a resource to see if FB is trying to access an a potential alternate resource when grabbing your image for display, the wall feed box that comes up is a webview. Meaning web graphics. (It's FB's web page…meaning their rules, and i doubt the pages' source is available to dabble with within the SDK.. so!…
Look at the HTML of the feed itself with safari browser:
The inspection of the HTML within the final resulting image that is posted on my FB wall I can see this….
<img class="img" src="http://platform.ak.fbcdn.net/www/app_full_proxy.php?app=153675474666495&v=1&size=z&cksum=773bba91f6146b2463eed0a0bb77dc42&src=http%3A%2F%2Fwww.thumbwizards.com%2Fspeakinapps%2Fgraphics%2Fboxed%2Faussie.png" alt="">
I am wondering:
Within HTML5 isn't there a mechanism to provide a toolkit type of javascript to display retina graphics from a web page?
Would it be possible to have that code run when grabbing the url to the image (in meaning, the url of the image would be acting as a pointer to the code.? I haven't tried playing with this, since my logic tells me that per the url above that FB is essentially taking control over the image at this point. I have noticed (and not waited long enough to see) that the image is apparently cached and posting to the wall with a new image, sometimes results in the older image still being used. (and yes, i've cleared my browser cache)… perhaps simply cached in another location..
If there is another parameter for the image type, that is not published, I have not stumbled across any yet.
Can anyone figure out if through source of:
[http://platform.ak.fbcdn.net/www/app_full_proxy.php] if this php file is part of an available image processor out there we can access to view what could be done?
Can anyone mention an app that uses a retina graphic in their feed post?
Just thoughts really, I've decided to not really give a crop, and if
you've made it this far. Thanks for tuning in. ..So, Sulf, your 30x30 is being scaled to 90x90. making it UGLY!.
Good luck.. If you figure anything else out, let me know!
Mark
apple specify that if you want to add the retina effect for your ios app then the images you are using in this format -i.e
sampleImag.png- 57*57(size) , 163 (DPI)
sampleImag#2x.png - 114*114(size),326 (DPI) when you use these specific graphic images you will get your app is showing retina effect in iphone 4 and above generation.
Just point your code to a larger scaled image and Facebook will take care of the rest.