Mediapipe: How to obtain unnormalized landmark coordinates?

[AlexYiningLiu]

I am currently running the mediapipe_multi_hands_tracking_aar_example.
Inside the MainActivity class I am able to obtain the normalized x and y coordinates of the landmarks by using getX() and getY() on the received NormalizedLandmarks. However, I am trying to extract the box of pixels around the finger tips for each frame. To do this, I need the unnormalized, precise coordinates of the finger tip landmarks. The incoming frames are 1080 x 1440 pixels, however the normalized landmark coordinates are all between [0,1]. Using the normalized landmark coordinates to map out the actual finger tip pixels will not be accurate at all.

How can I obtain the coordinates of the original, unnormalized landmarks and use it in my MainActivity? If this is possible, what do these unnormalized coordinates represent? Are they pixels coordinates? Thank you.

[Tectu]

Why do you think that it will not be accurate at all? The landmarks are at least single precision float point values.

I am successfully extracting the normalized landmark coordinates and then processing them further for on-frame drawing without any issues.

[mcclanahoochie]

The beauty of normalized coordinates is that they [generally] do not care what size of output is used.
Using getX()*width & getY()*height should be plenty accurate.

Let's say you have a hand coordinate, in pixel space, of (123,123) with your 1080 x 1440 image, and it moves 1 pixel up (123,124):
In normalized coordinates this would be
123/1440.0 = 0.0854166666666666
124/1440.0 = 0.08611111111111111
meaning there is a difference of
abs(0.08541666666666667 - 0.08611111111111111) = 0.000694444444444442
which floating point can easily handle, even more accurate than integer coordinates, allowing for sub-pixel accuracy.

[AlexYiningLiu]

I realize my misinterpretation now. Thank you all for the input. I do have a new issue about accessing raw camera frames and would appreciate any help. https://github.com/google/mediapipe/issues/793