I have an app that chooses an image from the Camera Roll or Takes a photo using the Camera. The problem is that when I run the app on an iPad, if I select an image it doesn't display the full image later on.
Image you select : (Notice that the waterfall is pretty much entered.)
Image displayed : (The image is displayed wrong)
The problem is only on big devices like iPads. I'm saving the image using CoreData and then recovering it. How can I get it to display the full I'm age?
Niall
You need to set UIImageView contentMode to ScaleAspectFit
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I'm coding an app where users can upload pictures and add some filters to it.
The problem is that when I apply filter on it, the picture is rotating, ONLY if the picture has been taken with back camera.
If it was a selfie the picture is not rotating
If the picture is in portrait mode, the picture is not rotating
The problem is that I don't know how I could get these information, in order to rotate the picture only when I need it.
You're thinking about this the wrong way. It may be the case that images taken with your phone's rear camera appear rotated after applying a filter, but you cannot make this assumption for all devices. Instead, you can read the imageOrientation property on UIImage to obtain information about whether the image has an unusual rotation.
I'm having a real hard time understanding this, but let's say I have an iOS app for both iPad and iPhone and I want to download an image from a server and display it in full screen.
I have read that the iPad pro has a resolution of 2732x2048 and if we want to display an image in fullscreen we would need to download the image with this size right? However, I also read that the image should never be over 300KB. I was not able to bring an image with this size under 2MB (I used JPEGmini for example to reduce size).
And I don't think that iPhone user would need to download such a huge image, so my question is: what resolution should my images be on the server and how can I manage to keep them in a rational file size. Also should I upload multiple images for different devices? If so, how many and at what resolutions?
Isn't the problem merely that you are holding incompatible beliefs? This is the belief that is giving you trouble:
I also read that the image should never be over 300KB.
Let go of it.
Clearly it is right to say that the image should be no larger than needed for display. But an image to be shown as a 3x scale image on the iPad pro needs to be 2732x2048. So that's that.
(You could, alternatively, use an image 2/3 of that size and show it as a 2x scale image. It wouldn't look quite as good as the 3x scale image, but it might be acceptable.)
On a smaller device, yes, you should scale down the image in code, so that you are not holding in memory an image larger than needed for display. But in this case, you need the large image for display.
On Snapchat, it allows you to take a full screen camera photo on iOS. The preview is full screen, and the image returned is full screen. There appears to be no cropping/stretching/etc... What you see is what you get.
Now I've looked all over the place, and I can't figure out how this is actually being done, seeing that the iPhone camera always returns an image with an aspect ratio of 4:3. Yes, you can use the camera view transform to have a full screen "preview", but the image returned is still 4:3 and needs to be cropped.
So my question is, how do you take a full screen camera photo on iOS without cropping? If your answer is that it can't be done, then how is Snapchat doing it (or appearing to do it)?
Snapchat isn't displaying everything the camera is picking up. By cropping a bit from the top/bottom or sides, they can create a 16:9 image from a 4:3 image. This is easy to verify.
Open up the snapchat and camera apps so it's easy to switch between them.
Place your phone on its side pointed at something with some marks for reference points.
Switch between the apps without moving the phone. There is content that you do not see on Snapchat.
I'm using UIImagePickerController to fetch images from the user's photo library and/or taken with the camera. Works great.
I'm noticing that fetched images are often (always?) coming back with their imageOrientation set to UIImageOrientationRight. But the image was captured with the device in portrait orientation. Why is this? This is an iPhone4S, iOS6, using the rear camera - so the resolution is 8MP.
In the simulator, grabbing photos from the photo library, images come back UIImageOrientationUp.
When I display the image in a UIImageView the orientation looks correct (portrait/up). But when I go to crop the image the coordinate system isn't what I would expect. 0,0 is in the upper-right of the image, which I guess makes sense when it reports UIImageOrientationRight.
I'm looking for an explanation of what's going on and the correct approach to dealing with the odd coordinate system.
EDIT: it sure appears to me that, on iPhone4S at least, the camera always takes UIImageOrientationRight/"landscape" images, and that UIImageView is respecting the imageOrientation on display. However, if I save the image using UIImagePNGRepresentation the orientation is not preserved (I think I read about this somewhere.)
It has to do with the orientation the phone was in when the image was taken. The phone doesn't rotate the image data from the camera sensor to make up in the image be up but instead sets the imageOrientation and then UIImage will take care of rendering things the right way.
When you try and crop, you typically change the image to be a CGImage and that loses the orientation information so suddenly you get the image with a strange orientation.
There are several categories on UIImage that you can get that will perform image cropping while taking imageOrientation into account.
Have a look at link or link
In my app I use a custom camera and when I snap a photo I want to see it in an UIImageView, it's all ok it work, but there is a little problem: when it put the UIImage (from camera) in UIImageView, the image sems a little flattened, then what's the exactly resolution that I should to set for UIImageView to have an exactly copy of my original UIImage?
ok, I set aspect fill in IB and it's all ok
The images resolution depends on the device that you are using. For the iPhone 4, it's 2592x1936.
I think it's more likely that you might be looking for the aspect ratio for the image, which is always 4:3. Keep in mind however, that a) you don't know whether the image will be portrait or landscape and b) that, if you allow to take an image from a photo album, you don't have control over the resolution/ratio at all.
So the most prudent thing to do might be to just set the UIImages fill mode to 'Aspect Fill' or 'Aspect Fit'.