The crop is a 16x9 pixels resized.
Thank you for your comments.
Sassi

looks like a pixel to me

Yes, this is a hotpixel. It should be on every picture on the same location, and depends on the length of the exposure.

A spot of dust on the sensor is just a blurry, grey, darker area around 4 to 10 pixels. Make a lightshot to find them all.

Point your camera to a uniformly lit, bright area. A clean white wall will do the trick.

defocus your lens and make a photo.

Blurry, big areas are dirt or dust on the lens.
Sharp spots are dust on the sensor (CCD or Cmos).

That's not dust.