[Python] How V4l2 10bit storage works?

This is the v4l2 documentation for 10 bit sensor: https://www.kernel.org/doc/html/v4.9/media/uapi/v4l/pixfmt-srggb10.html

According to this documentation I belive my 1 10 bit pixel should be stored like this

xxxxxxxx 000000xx


where first 8 bits are the lower byte and next 8 bits are the higher byte and first 6 of MSB are zeroes.

I get the sensor data through Jetson Xavier nx using the following command:

v4l2-ctl -d /dev/video0 --set-fmt-video=width=1280,height=720,pixelformat=RG10 --set-ctrl=bypass_mode=0 --stream-mmap --stream-count=1 --stream-to=file.raw


Here's my python code where I'm reading my raw file and printing it along with it's binary:

import numpy as np
raw_file_path = 'file.raw'
width = 3280
height = 2464
dtype = np.uint16
with open(raw_file_path, 'rb') as f:
data = np.fromfile(f, dtype=dtype)

if data.size != width * height:
raise ValueError(f"File size doesn't match expected shape ({height}, {width}). Got {data.size} elements.")

image = data.reshape((height, width)) # shape (3280, 2482)

print(image)
print(image.shape)
print(image.dtype)


image_bin = np.vectorize(lambda x: format(x, '016b'))(image)

print(image_bin)
print(image_bin.shape)
print(image_bin.dtype)


ANd here's the output:

[[4548 4996 4484 ... 4676 4932 4612]
[5125 4420 4996 ... 0 0 0]
[4676 5125 4484 ... 4612 5060 4548]
...
[4676 4356 4676 ... 0 0 0]
[4164 4420 4292 ... 4292 4548 4292]
[4420 4292 4420 ... 0 0 0]]
(2464, 3280)
uint16
[['0001000111000100' '0001001110000100' '0001000110000100' ...
'0001001001000100' '0001001101000100' '0001001000000100']
['0001010000000101' '0001000101000100' '0001001110000100' ...
'0000000000000000' '0000000000000000' '0000000000000000']
['0001001001000100' '0001010000000101' '0001000110000100' ...
'0001001000000100' '0001001111000100' '0001000111000100']
...
['0001001001000100' '0001000100000100' '0001001001000100' ...
'0000000000000000' '0000000000000000' '0000000000000000']
['0001000001000100' '0001000101000100' '0001000011000100' ...
'0001000011000100' '0001000111000100' '0001000011000100']
['0001000101000100' '0001000011000100' '0001000101000100' ...
'0000000000000000' '0000000000000000' '0000000000000000']]
(2464, 3280)
<U16


As seen there's no consecutive 6 zeros in my binary. How the 10 bit image is stored? Help me understand.

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