I am trying to develop an iphone application which needs to show a 360 degree video like the one and rotate the video as per the phone movement. How can i do this? Is it possible to do this with normal MPMovieplayer controller?
I don't think you can do this with a normal MPMoviePlayerController, but there are several libraries out there to achieve this. Have a look here:
PanoramaGL
Panorama 360
They work with OpenGL and you can embed them in your Objective-C code.
EDIT:
As #Mangesh Vyas kindly pointed out those are intended to use with fixed images only. However they might be a suitable starting point for embedding video as well, if you modify the code accordingly. They already do the handling of direction, accelerometer etc. so you don't have to implement all that yourself.
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I'm building an iphone photo app. I don't know how to achieve this kind of effect on an image:
When the user drags a finger across the arrow, I want the image to be distorted accordingly. How can I achieve this? Is there any framework that makes this process simple?
Thank you.
No clue about iOS, but the look reminds me of a thin-plate spline warp. It's quite easy to implement in OpenGL, a quick Google search for example code returns plenty of hits.
From the sound of it I think your looking for the CoreImage framework. Look into the various distortion effects...in particular CIBumpDistortionLinear.
I don't have any code so check out this tutorial and read up on CoreImage.
I am trying to piece together a solution to let users take and edit videos in an app. I have seen the 8mm app and am wondering how they did it... and made it so smooth.
At first I was thinking the effects might have been a series of pngs streamed together like a animated gif and then placed on top of the real video. but then for merging the images to the video I am at a loss. Also the app is so smooth I think it has to be using some low level Core.media Framework but am not sure.
Any ideas or advise on where to begin?
Thanks
AVFoundation combined with OpenGL ES 2.0 (with shaders) provides great performances for adding effects to camera / video in realtime (and even better with the ios 5 but i can't say too much due to the NDA).
You probably read most the documentation of AVFoundation to start with, because there is a lot going on. One method that might be of interests is this one:
- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection *)connection;
which allow you to work directly with blocks of data representing video information coming from the camera. You can then modify this data to change the video information, for example, adding additional content or pictures on top of the video frame. You can use Open GL ES to do this processing.
I am working on a project where I would like to open a video (on a Mac) with QTKit. That part I can do no problem, but as I am playing it, I would like to edit or modify the video on the fly using OpenGL.
From what I understand, I should be able to intercept the frames and change them before it hits the display, but no matter what I do, I cannot seem to do so.
It sounds like you should have a look at Core Video and the display link mechanic.
You can basically get a callback on a high priority thread with the decoded frame in a CVImageBuffer and do whatever you like with it (including packing it up as a texture for OpenGL processing and display).
Apple provides documentation and demo code snippets on the developer sites.
In my application I have a color video which I want to make as black and white video. Is there any framework that supports this in iOS? If so, how to implement that effect on color video?
Can anyone help in this regard?
A bit late here, but you should check out OpenCV.
It can be compiled as a static lib for the iPhone and can convert video (frame by frame) to grayscale or two color.
You can start here. There are other resources for doing this floating around.
HI Lakshmi this might be familiar to you that at least 24 frames make a clip of video so you have to use a tool like movie maker so that you can see the video frame by frame and edit each frame.
See the opensource Framework named: GPUImage https://github.com/BradLarson/GPUImage/
The filter name GPUImageGrayscaleFilter is what you want
This framework included the sample code, so you can learn how to use GPUImageGrayscaleFilter in your apps easily
Actually I am adding Image Processing Feature in my iPhone Application It should do Brightness, Contrast, Sharpen, Exposure....
But i am not able to Find any article/Tutorial on the Internet. Will you please help me to find any tutorial or tell me how can i implement the iPhone View Based Application.
I have found 1 link http://www.iphonedevsdk.com/forum/iphone-sdk-development/10094-adjust-image-brightness-contrast-fly.html its worked also for Brightness but its not working on iPad.
So Suggest something that i can start with my Image Processing Logic.
Thanks
Rick Jackson
I personally like the approach in the GLImageProcessing project from Apple's sample code. Check it out.
There are a few libraries that support image processing in Quartz. There are even a few categories on UIImage to do some basic stuff.
The following are a few examples:
https://github.com/esilverberg/ios-image-filters
https://github.com/cmkilger/CKImageAdditions
http://code.google.com/p/simple-iphone-image-processing/
But as said before by #Felz those libraries are slow because they use the quartz codebase, which isn't that fast (for example: changing the saturation of an image with a resolution of 1024x1024 might take up to 4 to 8 seconds, depending on which device your using).
If your project is iOS 5 or higher then you should definitely consider using CoreImage
You can try GPUImage framework created by Brad Larson. It includes awesome image filters and also easy to use.