Focusing box on QRCode scanner on iOS 7 - ios7

I'm investigating if it's possible to implement the same functionalities of ZBar library with iOS 7 api.
Everything was good so far thanks to this tutorial.
However, I now want to have a green box shown on the screen whenever the camera detects a QRCode. The green box is supposed to wrap around the QRCode.
From the delegate of AVCaptureMetadataOutput, I can grab AVMetadataObject but the bounds getting from this object is always very small which is not correct, given the fact that my QRCode is very big on the screen.
Anyone has any ideas on how to achieve the green focusing box?
P/S: I came across the documentation and couldn't understand this line "If the metadata originates from video, bounds
may be expressed as scalar values from 0. - 1.". This is for the bounds property of AVMetadataObject

You can look at this tutorial for qrCode scanning using iOS 7.

I had to do the same thing in my scanner app. Here is a link that I found very useful and pretty much answered all my questions.
He goes step by step from setting up the scanner to adding the bounding box.

Related

Unreal Engine 5.1 Retargeted Animation From Manny to Mixamo Model Causes Single Animation Sequence To Rotate 90*

I apologize if this has been asked before. I tried searching for this first and nothing is coming up. I'm pretty new to Unreal Engine 5.1 so this might be something I'm doing as well.
I've been exploring animation retargeting in unreal and have tried following the steps we learned in class using one of the models from mixamo.com. Everything appears to work fine at the start and I can get the actual IK and IKR objects working just fine. However when I try to export the animations either from the IKR object or by right clicking the ABP object for the source mesh one and only one of the animation sequences rotates 90*. It is always the same animation (the Land animation sequence) and I'm not sure how to go about fixing it.
Also tried looking on google and turned up nothing.
I'm hoping this is some stupid newb mistake that is easy to fix or maybe there's something I'm overlooking. Any help is greatly appreciated and I will continue trying to fix the problem myself as well and will post if I fix it
Tried retargeting using the following steps
Create an IK_Object for the model you wish to project your animations on with chains for each. Mine looked like the following
IK_Remy
Repeat step 1 for the model you wish to source animations from. Mine looked like the following
IK_Manny
Create an IKR_Object Linking the two together, here's what mine looked like
IKR_Remy
Find the ABP for your source model, right click, and select "Retarget Animation Assets->Duplicate and Retarget Animation Assets". Here's what I'm selecting for that
Retarget Dialog
When I do the following most of the animation sequences for "Manny" export just fine. However the "Land" animation flips for some reason (see image below)
Exported Animation Images
Even stranger, when I preview the MM_Land animation in my IKR object it looks fine i.e. not rotated. However, if I try to export the animation from the IKR object the same thing happens i.e. it rotates 90*. I would expect this to be a case of WYSIWYG where if it's working in the preview it would export correctly. However that apparently is not the case
Also I tried modifying the animation sequence manually but it won't let me. If I try to rotate the model in the animation sequence and save it, once I close the sequence it's re-rotated and the changes do not persist.
I can export the sequence as a new sequence, modify it, and save it, and then rename it as my exported "Land" animation to hard force it and it at least looks normal. However when I actually play the game and jump, when the land animation it still flips sideways and in addition causes the character to scale and warp for a second which makes me think there's something going on here that I don't know enough to fix. Really hoping someone with more experience in Unreal Engine can help.
EDIT: Fixed Image Descriptions
I can confirm that this is an issue - I'm seeing the same behaviour. I haven't managed to fix it yet, but my suspicion is that it's due to scaling - in my instance, I have had to scale up my custom character by around 2.5 times to replicate the scale of the default mannequin. Did you scale your custom character at all?

OpenCV cvFindContours questions

I'm following this guide: http://www.aishack.in/2010/08/sudoku-grabber-with-opencv/2/
and modifying to iOS 5.0.
I managed to find the largest contour (the sudoku "board"), however, it only locates the surrounding square, without the lines inside, as in the tutorial. can this be easily solved?
I'll try and find a way around it, but still would like to know. thanks!
I assume that you are using the camera right now. Try to load the image what is used in the tutorial and check if your implementation works on that image. Then you can continue with nice sudoku images from the web. You may also change the camera angle and distance from the sudoku when taking pictures to get a better, clearer view.

iOS: compare a slice of an image to library of options

I'm basically trying to work out how to take a slice of an image, say a screenshot of an iPhone home screen, slice out the first icon and compare it to a set array of images in a library. Any help on where to start?
I'm no iPhone programmer, but I might be able to suggest a few things:
The SURF feature detection implemented in OpenCV should help you with this
There is a nice article on using OpenCV in Objective-C code.
A quick & dirty way might be to use the difference blend mode which should return the difference between the 1st image(top) and the 2nd image(bottom). If there is no difference the result will be completely black. So, the more black pixels in the difference result, potentially, the more similarities between the compared images.
I'm not an iOS developer, so I don't know if there is an image library that ships with sdk or if there's a free/opensource library for basic image processing. Still this should be trivial to implement:
e.g.
- (int)difference((int)topPixel,(int)bottomPixel)
{
return abs(topPixel-bottomPixel);
}
Note: Syntax might not be correct :)
HTH
This may not help you with taking a screenshot of the iOS home screen... But these articles show how to take snapshots from within a UIKit application:
https://developer.apple.com/library/prerelease/ios/#qa/qa1703/_index.html
https://developer.apple.com/library/prerelease/ios/#qa/qa1714/_index.html
Perhaps you would instruct the user to press home-power (buttons) to take a snapshot and store in the photo roll, then load that screenshot into an app to process the screenshot.
Hope this helps!

Floating pictures screensaver on Mac OS X

I'm just learning to use XCode and program in Objective-C (my plan is to write a an app we need for my business since I can't find one that does what I need). It's going well and as an exercise I've been playing with database apps and screensavers.
I'm trying to write a screensaver that all it does is to show 3 or 4 pictures randomly floating on the screen. Similar to the out of the box pictures screensaver that comes with Mac OS X.
I've played with the code in http://cocoadevcentral.com/articles/000088.php and while very informative I still don't know how to add those 3 or 4 pictures and make them move.
Anyone out there can point me to sample code? Or a project that I can use as reference?
Again, this is just self learning.
Thank you!
This will probably be your first port of call.
My approach to this was to create a Quartz Composition using Quartz composer. I found this easier than figuring out how to draw and animate everything by hand.
You can display a quartz composition inside a ScreensaverView by using the QCView class. This setup worked well for me.

Image Processing in iPhone

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.