Images showing in simulator but not on the iPhone device - iphone

So when I run the application from the device the pictures show up and everything works great. However, when I move to the device I run in about 10 out of 38 pictures that don't show up. I am pulling the names for the images from an sqlite database and I already checked and the names are correct, case and everything. I checked the bundle and the images are correctly in there.
Does memory play into effect in this? I am not really sure what else could cause this to happen??
Thanks!
Solution:
The files somehow were not saved properly and were unable to be opened by say photoshop or paint even. So with the files not being able to be open they weren't showing up... Thanks for the help everyone!

First thing to check is the case of the strings you're using to refer to the resources. The iPhone is case sensitive, but the simulator is not.
Oops, just seen that you checked the case. Better log all your UIImage creation calls then!

The simulator accepts a wider range of image formats. Sometimes you had a specific file type that the device cannot display. Double check the 10 files looking for some difference from the others ones.

Yes, memory absolutely plays into this. Check your UIImage creation calls and make sure they dont return empty. Also, check to see if youre getting memory warnings in the console window.

Generally, if in-memory size was the culprit, your application would crash with a low memory error on the device. However, it seems like the images just don't display.
One other thing that can be going wrong is the size of the images. UIViews on the iPhone can only have dimensions smaller than the maximum texture size supported by the GPU. Apple states that this is 1024 x 1024, but I've found it to be more like 2048 x 2048 on even the original model iPhone. You may be creating a view for some of these images that exceeds this size in one dimension, but your Mac has a larger maximum texture size on its GPU and so it displays fine in the Simulator.

Apparently the iPhone caches the launch screens. So in my case, I had to reboot my iPhone before being able to see the image.

Related

Unity - Texture2D.Loadimage resulting in MemoryWarning

I currently work on a 2D project on Unity (for mobiles/tablets), where I download a few heavy pictures by using UnityWebRequestTexture.GetTexture(url), which I then store using File.WriteAllBytes(filePath, webRequest.downloadHandler.data).
Later in the project, I need to show the downloaded picture on a RawImage element. To avoid blocking the app I read the bytes via FileStream on a separate Thread, which works well.
But when I call (from the main thread) ((Texture2D) myRawImage.texture).LoadImage(loadedBytes), my Profiler shows a huge peak, and if most devices handle it correctly, on iPad Mini I often get a MemoryWarning at this very point. Which, when repeated, leads to the app being forced close by iOS.
For info, the downloaded image's size vary depending on the device asking it. We initially intended to display 2048x1536 pictures that way on iPad Mini, but we were getting MemoryWarning on each display. We're now using 750x1334, but we still get MemoryWarning from time to time.
My question then is : is there a better way to do the "LoadImage" step ? I believe that the conversion from byte[] to Texture2D is where my memory problem lies, but I didn't find any workaround to this.
Or eventually: Is there a better way to download/store the image? If the image was in the app's resources from the beginning, I don't seem to have any trouble displaying it on the same device. Maybe there is a way to download the texture while applying it the same compression algorithm that assets receive when building an app ?
Using Texture2D.Compress() after loading the texture compresses the texture by at least 90%.
Reference

CCSprite memory overflow

I need to create and show 10 images using cocos2d. Each will be placed above previous one and all will be visible simultaneously (all of them has transparent areas). Each image has resolution 2048x1536.
When I create 5 or less CCSprites the app run fine, but when I create 6 CCSprite - it crashes on device (iPad) with error "Data Formatters temporary unavailable".
I suppose it's lack of memory, but maybe someone knows any approach for for this situation
Thanks!
A transparent image of this size uses about 12mb ram (2048*1536*4 bytes).
You are lucky that you get 5 images of this size shown before your app crashes.. which usually happens at about 50mb ram usage.
Without more knowledge about what you want to do or need to display I can't give any advice what to do .. but you won't be able to show 10 images of this size.
edit: since you are using cocos/opengl you might be able to get more images shown by changing the image format to rgb4444. This will cut the memory need to the half but you also loose much quality on your images.

Default-Portrait.png for iPad: any way to make the file size smaller?

I'm making a Universal App using MonoTouch, and I'm adding my Default-Portrait.png file. That file alone (a 768x1004 .png file) is adding 711k to the size of the app. My app itself is only about 7 megs, so it's adding 10% just for the splash screen.
I could easily make this thing an 80k jpg file instead of a png, but the device doesn't seem to look for a .jpg file. Does anyone have tips for reducing the size of this launch art?
At this point, I'm thinking I might just leave the launch art out and load my own jpg and display it as soon as I have the ability to. That'll keep my app size down, but it's not as nice as having the launch art scale in immediately like most apps do.
Hmmm...given the screen of the iPad and the visual quality users are expecting, I'd just leave it like that.
But if you do want to reduce the disk space, try going to Project > Edit Project Settings > Build (tab at top), and searching for a parameter called "Compress PNG Files." Make sure that's checked. It'll run the pngcrush utility before loading the file onto disk (check the size of your IPA archive after to see if it had any effect).
pngcrush is nice as well, however that will not reduce the quality of you image. If reducing the quality of the image is an option for you, then you might try this tool: http://www.punypng.com/ - or just use an image editing tool to "optimize" the image ...
I recommend pngout if you want to really squeeze those PNGs down, and this won't cost you any quality. It simply removes unnecessary metadata (like pngcrush) and uses its own compression algorithm which is compatible with the regular decompressor used in PNG (zlib). It's really slow, though.
A simpler option is to try "Save for web" in your image manipulation program of choice. Exporting from Acorn (not just the regular save) sometimes gives me vastly smaller files. This is especially true for default images which have large, uniform areas in one colour (screenshots, a small logo in the middle of a black screen).
Is there any reason why you want to reduce the file size that badly? I don't think it matters in your case. I just checked 3 of my apps and the Default.png (of various portrait/landscape varieties) is between 29KB and 422KB, so whilst yours do seem a little heavy, your still way under the 3G download limit.
Are you positive it's adding that much to the size of the app? Did you compare a before and after?
Xcode uses pngcrush on the images for you. I know because I just tried to substitue jpegs for pngs and got the following result:
So, in short, there's not a lot to be done except simplify the image beforehand. Xcode will handle the rest.

iPhone 4.0 Screen Resolution and writing robust code

Does anyone know what will happen with existing apps when they run on the iPhone 4.0 in terms of the new screen resolution? I am assuming, just like developing for the iPad that there should be no hard coded screen resolutions in your code.
I'd also like advice on the best way of writing robust code to work well on any device. For instance, detecting the screen resolution is not enough - on the iPad the screen is physically bigger so you can display more items on it. On the new iPhone the screen is the same physical size but higher resolution, so the likely thing is that you wont want to display more items, just higher resolution versions of them.
Any help would be useful,
Regards
Dave
EDIT: I have read the other similar posts, I guess what I really would like to know is what is the recommended way to write code for all App Store devices in a robust way so they a) all work b) make best use of the device.
UIKit has be redesigned so that old apps just work unmodified in the iPhone 4. There are then several things you can do, some programmatic and some by just adding higher resolution images to you app bundle.
Firstly, and most simply you can include new double res images that are used by your app with a suffix of #2x in the name. i.e., Event.png as well as Event#2x.png. [UIImage ImageNamed:] will automatically look for the a file with this suffix if it is running at the higher res.
All the other UIKit stuff now uses points instead of pixels. So for both old and new apps full screen is still 320 x 480 points. This pretty much means everything will work including touches, etc. Although they may now return fractions of a point.
The only real gotcha so far seems to be if you use CGBitmapContextCreate as this uses pixels and requires some jiggery - pokery.

How to display images in a tableview

I can display images in a tableview but can't transfer the application on to the iPhone. I am obviously not releasing some memory but can't figure out what. I have approx 30 pix that are each 250k in size. I have tried storing the images in SQLite as well as the filesystem and get the same problem for both; works in the simulator but does not get to the iDevice (touch actually).
Suggestions?
Check your images are in 24bit format if they are PNGs
I think the problem is to do with image formats - not a lot else makes sense.
What do you mean by they are in a tableview - is this relevant? Can you see them when they are not in a tableview?
No Sample code to review, but have made sure that your not allocating or holding the images more than once. 30 pics at 250k is 7.5MB plus the code, so that app starts off hefty. If the images are not being released, the size could be sending Memory Warnings. Do you have an NSLog("Warning Message"); in your application's - (void)didReceiveMemoryWarning {..} Try setting one if not and then run app in the Simulator with the Console open and double check that MEMORY is not your problem. If that NSLog gets triggered you know that is where the problem is.
I think its too much for the tableview to show this big images on the iPhone. And if it would work you would also have a problem with scrolling performance in the tableview.