UIImage gets distorted/wrong size in UIImageView - ios

I have two UIImageView with dimension 64 x 16 and two images (#2x):
image1 (128 x 32)
image2 (80 x 32).
I've placed image1 in imageview1 and image2 in imageview2.
When I run the app, imageview1 looks ok, but imageview2 looks distorted. How to deal with different image sizes? I want the UIImageView size to be fixed (64 x 32).
Any help would be really appreciated


image1 with dimension 128 x 32 and image2 with dimension 80 x 32
Your 2x image should have 160 x 64, not 128 x 32.
Edit:
If you have a 64x16 points of UIImageView, that results in 128 x 32 pixels on a 2x scale screen, if you have an image with 80 x 32 pixels, that will get disorted if you try to put it inside a 64x16 point (128x32 pixels) UIImageView

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Convert Centroid points generated at Image Size 640 * 640 (image size) to size 622*1186 (image size)

I want to convert point (i.e 622,622) coordinates to other dimensional coordinates (622*1186) Using OpenCV. i.e I currently plotted the data at Image Size 640 * 640.
Now I want to plot it at 622*1186 Image size. I want to know the formula so that I can convert them. I am working with OpenCV.

Ok, So I am answering my own Question!
The formula to convert the point (x, y) from the original size (width_original, height_original) to a new size (width_new, height_new) is:
x_new = x * width_new / width_original
y_new = y * height_new / height_original
So, in the above case:
x_new = 622 * 1186 / 640 = 622 * 1186 / 640 = 1176.25
y_new = 622 * 1186 / 640 = 622 * 1186 / 640 = 1176.25
So the new coordinates of the point would be (1176.25, 1176.25) in the 622 x 1186 image.

Camera Intrinsic Matrix for DJI Phantom 4

I am trying to estimate a gues for the intrinsic matrix, K, of a DJI Phantom 4 drone. I know that the form of this matrix is:
but i cant seem to get the units right. Looking up the specs at https://www.dji.com/phantom-4/info#specs I find that the focal length is 8.88 (dosnt say units...) and the image dimensions are 4000x3000. WHat would K look like with these?
*PS, I am scaling down the images so they are smaller. Will this effect the K matrix I should use for openCV?

The page the OP linked to lists a FOV of 94 degrees. With an image width of 4000 pixels this corresponds to a focal length of
f = (4000 / 2) pixels / tan(94 / 2 degrees) = 1865 pixels
Absent any other calibration data, one should therefore use an estimated camera matrix of the form:
K = [ [1865, 0 , 2000],
[0 , 1865, 1500],
[0 , 0 , 1 ] ]

OP, you may have confused the specs of the P4 and the P4Pro, which have different sensors and lenses. The P4Pro, not the P4, has a focal length of 8.8mm. The P4 has a focal length of 3.61mm.
If you are indeed using images from a P4, Francesco's answer is correct.
However, if you are actually using images from a P4Pro, you need to use these values:
f = (4864 / 2) pixels / tan(84 / 2 degrees) = 2701 pixels
K = [ [2701, 0 , 2432],
[0 , 2701, 1824],
[0 , 0 , 1 ] ]
For future reference for anyone that may find this answer, here are the relevant specs for the P4 and P4Pro sensors/lenses:
Phantom 4:
Sensor size: 1/2.3" (6.17mm x 4.55mm)
Focal length (actual): 3.61mm
Focal length (35mm equivalent): 20mm
FOV: 94°
Image size: 4000×3000 pixels
Video frame size
UHD: 4096×2160 pixels
4K: 3840×2160 pixels
2.7K: 2704×1520 pixels
FHD: 1920×1080 pixels
HD: 1280×720 pixels
Phantom 4 Pro:
Sensor size: 1" (12.8mm x 9.6mm)
Focal length (actual): 8.88mm
Focal length (35mm equivalent): 24mm
FOV: 84°
Image size
3:2 aspect ratio: 5472×3648 pixels
4:3 aspect ratio: 4864×3648 pixels
16:9 aspect ratio: 5472×3078 pixels
Video frame size
C4K: 4096×2160 pixels
4K: 3840×2160 pixels
2.7K: 2720×1530 pixels
FHD: 1920×1080 pixels
HD: 1280×720 pixels

I think it is much better to work from the focal length in mm
https://www.dxomark.com/Cameras/DJI/Phantom4-Pro---Specifications
For P4 Pro:
13.2 x 8.8 so pixel size is = 0.00241 or 2.41 um focal length is 8.8mm
so focal length in pixel = 8.8 / 0.00241 = 3684.6 pixels
Incidentally in the image metadata, there is a field:
CalibratedFocalLength 3666.666504 (use exiftool to find it) so I think K should be
K = [ [3666.6, 0 , 2432],
[0 , 3666.6, 1824],
[0 , 0 , 1 ] ]

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Multiply x and y proportionate to the new image width and height for each coordinate pair:
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UIGraphicsBeginImageContextWithOptions(finalCanvasSize, NO, 0.0);
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