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.
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I'm using UIImagePickerController to snap an image and uploading it to server.
When taking a photo in the front camera, the height/width get reversed somewhere.
The image is displayed correctly later, but height and width are reversed (and I'm using them for the UIImageView autolayout constraint)
The thing is - that when looking at UIImagePickerControllerMediaMetadata of front and back camera images - the EXIF and the rest of the metadata is the same (resolution is smaller but the height/width ratio is the same)
Any ideas what is the difference?
Apple images are always landscape left with EXIF and the orientation is specified in the EXIF.
OK, so #zaph comment is correct, apparently back camera images are "reversed" as well - the upload code in the server (Codeigniter PHP) ignored the EXIF.
The problem surfaced only due to front camera low resolution...
We're developing an AIR app for android and iOS. An important part of the app is taking photos. Using flash.media.CameraUI works perfectly on android, but we experience problems on iOS.
In the iOS camera application, when we rotate the iPad, the orientation is wrong: If we rotate the pad clockwise, the image is rotated anticlockwise. The UI buttons have the correct orientation though, and when the photo is taken, the resulting bitmap has the right orentation based on the orientation of the camera, not the actual view on the screen.
Looking at different camera apps, I notice that when the pad is rotated so the orientation changes clockwise, the camera does three things: First, the displayed image immediately becomes rotated 90 degrees anti-clockwise (so it looks wrong). Then, the image slowly rotates 90 degrees clockwise, to restore the correct orientation. In addition, the UI buttons change orientation so the text is displayed correctly.
It seems as in our app, it only rotates the image slowly without doing the first immediate rotation. Thus, the end result is wrong.
Anyone know how to fix this?
After some more research, I found that the issue isn't just restricted to AIR.
UIImagePickerController camera view rotating strangely on iOS 8 (pictures)
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.
When your taking a photo with a camera, your not getting all the camera view right?
I mean in a portrait photo take
I will have much more hight then a landscape photo:
Where ill have much more width, right?
But the camera is a circle so that means the the image can be actuality taken with a larger area, I mean the hight and the width together!
The camera is probably getting the hole image, but cropping it according to the screen, landscape or portrait.
If i would like to get the full image that the camera is getting, how can i achieve that?
Any suggestions would be much appreciated, thanks!
Edit
After a long search that came out with nothing so far, even if someone knows about a way to display a landscape camera, in a portrait mode, that would help to.
What i mean is display a view were there is more to see on the left and right sids, hope i'm clear enough with my question..
Actually, the sensor has roughly the same proportions as the screen. Its aspect ration is around 1.33 (4/3) or maybe 1.5 (3/2), depends on the phone model. the only round thing in the camera is the lens that projects a circle of light around the sensor. When you rotate your phone the sensor is naturally rotated as well so you always get the full output in every shot.
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