How to give sketch effect on image in iphone? - iphone

I am implementing an iPhone application, in which I have implemented the following functionalities:
Select photo
Capture photo
Now I want to give a sketch effect to that photo like this one.
How could I do this?

If I may once again recommend it, my open source GPUImage framework has a built in filter that does just this. The GPUImageSketchFilter uses Sobel edge detection to highlight edges in black on images or video, leading to the exact same effect as seen in that application:
The above image was drawn from this answer, where I describe how that filter works, as well as show a couple other filter examples.
In fact, the SimplePhotoFilter example application that comes with the framework does exactly what you describe (capture a photo, apply a sketch filter to it, and save it to the photo library), so I'd start there if you want to get this up and running quickly.

OpenCV can be used to give sketch effect on image in iphone.
Refer iphone-how-to-convert-a-photo-into-a-pencil-drawing link and get helped.

Core Image filters are probably the best way to go.
http://developer.apple.com/library/ios/#documentation/GraphicsImaging/Reference/CoreImageFilterReference/.

Related

Focus to a object in square form using ios Camera?

Actually I need a region over camera overlay like mostly of the QR code scanner app.
And when a square box comes within it just focus and click picture from it. Any idea how to implement it. I was using the UIIMAGEPICKER class but after doing some googling I found that I need to use the AVFoundation framework. But unfortunately I am not the near one.
Any code or any tutorial will be helpful. Please let me know how can I implement this.
One more thing if i need to take picture can i make the picture only to the region size?
Yes, you are correct. You will need to use AV Foundation to implement this. Have a look at the 'Using the Camera with AV Foundation' video from the WWDC 2010 session videos, to get an overview of the framework.
AvFoundation has no Dependancies on UIKit. So you will get some nice performance increases over using UIImagePickerController. It will also give you Full Access to the camera.
When using AV Foundation you are in control of the 'Device Capture Settings' i.e. Flash as well as Focus Mode and Exposure; including their points of interest. Have a look at the Programming Guide to see how to use these, or the device behaviour may differ from what you expected.
You can also download and example of an application that uses AV Foundation to implement the camera here.
Once you're up and running with that, have a look at this tutorial to get started with the overlay on the camera.
One more thing if i need to take picture can i make the picture only to the region size?
Yes you will be able to implement this. You can also configure the AVFoundation session itself to output the lowest practical resolution.

How to add Cartoon Color and Cartoon B&W filter effect on Image in iPhone [duplicate]

Is there any filters available in ios to convert a image to cartoonistic image like exactly in the above picture?
For a much faster solution than ImageMagick, you could use the GPUImageToonFilter from my GPUImage framework:
It combines Sobel edge detection with posterization of the image to give a good cartoon-like feel. As implemented in this framework, it's fast enough to run on realtime video from the iPhone's camera, and is probably at least an order of magnitude faster than something similar in ImageMagick. My framework's also a little easier to integrate with an iOS project than ImageMagick.
If you want more of an abstract look to the image, the GPUImageKuwaharaFilter converts images into an oil painting style, as I show in this answer.
Try to use imagemagick for iOS http://www.imagemagick.org/download/iOS/
Of course you need some serval hours how to use imagemagick for iOS.
But then you should also look at: http://www.fmwconcepts.com/imagemagick/cartoon/index.php
and maybe also on:
http://www.imagemagick.org/discourse-server/viewtopic.php?f=1&t=11140&start=0&st=0&sk=t&sd=a
This Core Image filter section in the iOS dev library, possibly combined with the script referenced by Jonas and a little luck, might get you where you're going. Not sure, having never used either of these technologies.

How can you change a picture on the iPhone to make it look comicy or black and white?

I was wondering, are there any libraries on the iPhone that allow you to take an image and apply some sort of filter to it so the image turns out black and white, or to make it look comicy, or to skew it?
Start by taking a look at CoreImage. Its available in iOS5. You'll probably want to explore third party options too.
Check out OpenCV. It's an open source library that can be compiled for iOS (there's plenty of tutorials all around the net) and it's specifically made for things like image manipulation.
While it's harder to set up, it's a lot more powerful than CoreImage will be!
There's also plenty of sample code around the net that does things like turn images comicy/black and white/find image outlines/thresholds images etc. There's a small learning curve, but for what you want to do, it's more than worth it :)

iOS: Getting started with the Camera and Custom Image Editing

My app will let users cut out things from photos. They'll be able to either select a photo already in their iPhone's photo library, or take a new one with the camera. From what I understand, UIImagePicker is the simplest way to accomplish picking a photo from the library or taking a new one. However, I also understand that it only provides basic image editing (zoom, crop). I want my image editing to allow for the creation of Bezier curves that, once all joined together, will cut out the enclosed area, saving it without the surrounding background.
The official apple documentation on UIImagePicker suggested that the AV Framework is required for providing custom image editing as opposed to the basic zoom and crop. So my first questions are:
Is the AV Framework indeed what I want to
use?
Will it get used in conjunction with UIImagePicker (i.e., UIImagePicker is used to select the photo or take a new one, and then my AV Framework code takes over for the image editing)?
Can anyone offer good resources on getting started on learning the code for this process?
My final question is about the actual Bezier curve generation/manipulation. It appears that the Core Graphics Framework has support for this, but there is also the UIBezierPath object, which is apparently some kind of wrapper for the Core Graphics tools I would otherwise use.
So my final question: will I want to use the UIBezierPath object, or does what I previously described require more fine-grained control that UIBezierPath can't provide, thereby forcing me to use the Core Graphics framework directly?
Thanks!
the AV Foundation allows you to talk to the camera, to configure it in various ways, and to receive a live feed from it. So it's good for taking new pictures or movies, but not for selecting them from the camera roll or for editing them. You'd likely want to use the AV Foundation to replace the image capture duties that UIImagePicker supplies. Probably you'll want to use a UIImagePicker with allowsEditing set to NO so as to be able to provide your own entirely separate editing interface.
no, it's a different sort of task.
I'm unaware of any tutorials on this sort of thing, but the docs are pretty good. I've posted the whole stuff for capturing a live feed from the camera in answers like this one, not sure if that's a more helpful way to see how some of the AV Foundation classes can be chained together?
What you'll probably end up doing in order to edit an image is starting with a UIImage, creating a CoreGraphics bitmap context (which is something you can draw to), doing some sort of compositing to that and then converting the result into an image and saving it back out to the camera roll.
UIBezierPath is a wrapper over the Core Graphics stuff, but will probably do what you want. addClip can set a defined path to be the new clipping path on the current context, or you can use the CGPath property if you need to go a bit further afield than UIKit's idea of a current context.
look for the iphone cookbook, maybe kickasstorrents still has it
C07 has everything you need, camera, overlay, loading, picking, editing, snapping,hiking camera, saving doc, sending image, image scroller, thumbnails, masking, etc....

iphone 4 - How do I record the video overlay on top of the video also?

Does anyone know how to do this?
Is anyone able to provide an example? I believe this is out of NDA now as was available in version 4.0 ?
Take a look to AVFoundation framework , specially to avcapture avsession avinputdevice, etc. You can find some listings in the iPhone dev center forums: search "avcapture"
AVFoundation is the framework you want to use to record, modify raw frames, show them, an offcourse add some overlay
If you want to do only overlay then, UIImagePickerController should b enough.
If i understand, what you are trying to do corectly, you have set up video capture someting like suggested by Apple in this Q&A:http://developer.apple.com/iphone/library/qa/qa2010/qa1702.html
From there it shouldn't be much of a Problem to use the method described in this answer:blend two uiimages based on alpha/transparency of top image to blend the preview with your overlay, provided you draw it in a UIImage first. Feed the resulting images to a buffer and save it accordingly.
Though, this method most certainly wouldn't give you a lot of frames per second.