I'm trying to develop a sort of AR for BlackBerry devices. Trying to achieve the best compatibility for old devices, if it's possible I would like to make it for BlackBerry OS 5 / 6.
Due to lack of hardware performance, I'm not trying to show a real-time solution on screen. Right now I just want to recognize some symbol that the camera see, at the moment the symbol is recognized I want to capture a photo of the current view.
After that, I want to crop part of the captured photo and compare it with a imagery and determine if it matches some image.
I'm quite advanced on researching the alternatives, for the image comparing step, I know there are two common techniques histogram and keypoints. I'm almost decided to use histogram method, but I'm worried about the colors captured by the camera could be a little different from which ones I got in the database (due to light sources, colors, etc.)
Any ideas of which is the best method to achieve what I'm trying to do?
Thanks!
Related
I'm new to Augment Reality and not having a compatible device to run examples provided for ARCore. I am having a few questions and want them to clear before going further as I'm getting clear about those through any mean. The app I'm working over is gonna perform the following task.
Detect a logo from a product
Create a 3D model of it using AR
display the generated 3D model at the exact same surface
Here is a sample image captured from a box. I want to display the text and logo in the 3D model.
My Questions
is it possible to display both logo and text as a 3D model or AR
supports images only?
Should I use ARCore or OpenCV or any other to do the task? which one is efficient regarding time and memory to implement?
Maybe it would be a discussion-based question but I am literally unable to find a solution for it.
Thanks everyone!
If you do not have ARCore supported device, you can try Vuforia + Unity instead. Vuforia also supports image recognition and overlay with AR. Check out this tutorial for your use case.
If you still want to use ARCore, you should check out Augmented Images feature. The challenge here if your logo has a good score to be able to work nicely for tracking and overlaying AR.
You can check image quality/score with this tool.
I'm a 17 year old trying to start developing some android games. I've used LibGDX once before and found it a pretty effective tool, so I'm using it again now.
The game I'm making is a choice based, interactive game where you make a choice and then the next scenario happens based on your choice, and it goes on and on until your character dies or you win. I'm expected to have around 200 scenarios by the time I'm done, and currently have around 160.
The problem I'm having is that each of these scenarios is basically a "card," with a picture, scenario description and 2 options below it. Each of these images is pretty big, and if I scale the card images down they start looking pixelated on the phone screen. I'm worried that in just images, my game will reach 100mb, and then with sound effects and everything else it might be like 200mb. This seems pretty inefficient and I don't want potential players to shy away from the game just because of it's size, if they don't have enough room on their phone...
Am I doing something wrong? I apologize for this inexperienced question, I'm really new to Android development.
That isn't too big for modern games but you will need to not include the assets in the apk and either download that when needed or use what Google already thought of for this problem.
https://developer.android.com/google/play/expansion-files.html
These are some steps that can help you reduce your apk size:
Use only specific drawable
Add only specific image size for each drawable directory for drawable-mdpi, drawable-xhdpi, drawable-xxhdpi, etc. You can try removing a drawable directory that could potentially unused by the user, like drawable-mdpi and drawable-xhdpi, and use only the hi-res one like drawable-xxhdpi. Or, you can try using only drawable directory for all the images, so your app will only use one image for all devices type.
Resize your images
Compress your images
If your images are PNG files, You can compress the images without a noticeable change using pngquant. In fact, it can reduce your images sizes significantly (often as much as 70%) and preserves full alpha transparency. Or you can try using pngcrush (I'm rarely using this)
Im just made my first little app on android.
I've been using the Android Studio for developing which is quite good but the problem is that the app I designed fits only a 5.5" display. On other devices its just very small or larger. I don't know how to make it autosize according to the size of the device.
Is there any way to fix it or is there any way to make different Apks for different mobiles (according to the display sizes)
PS: there isn't any picture in the app. Just writing and calculations. Kind of Calculator for beginners(ME). :)
If you dont have any images on your app, set your layouts and views width (when needed) to 'match_parent' instead of 'wrap_content' or a fixed size.
Set the parent layouts height to 'match_parent' and if you have a background that fits all the screen, set this too.
Check this for reference of LayoutParams values: http://developer.android.com/reference/android/view/ViewGroup.LayoutParams.html
If you want to add images Go to http://developer.android.com/guide/practices/screens_support.html and try to understand all the concepts of densities independence and supporting multiple devices.
I am working with LibGDX at the moment.
I understand why DPI matters for android, but was wondering if it even mattered for desktop development.
My question is this, does DPI matter at all or affect games for desktop?
If so, is it in the same way that it does for android?
If not, how is it different?
It depends.
If you need to keep the same physical size across devices, then it matters. Eg. You need an image to be 1" on both phone and tablet.
If you need to keep the same proportions across devices and are only dealing with different aspect ratio's, then DPI will only be useful if you want to have a good idea on what a finger can achieve on a screen, which is usually 50 dp.
Hopefully not making this too vague... but I have been dealing with a lot of image scaling and manipulating with an app I'm working on and wanted to know:
Is it possible/feasible to warp images using java code and if so, is it possible? I have read up on JAI but can't seem to grasp it very well. Is there any form of built in implementation that would work with Android 2.3 or higher?
Any tutorials or examples that someone may have come across would be a great help as I have been researching for a while and can't seem to gain any ground.
End goal: to be able to warp an image (point to point by pixels) in multiple places and then saving the bitmap. This would be processed behind the scenes and show the user the end result.
do you have an example of the kind of warping that you want to do? It's certainly feasible but you'll probably end up doing pixel-by-pixel manipulation to generate the warped image.
there is a previous discussion here:
android image processing tutorial?