Question

When an object moves at a very high speed relative to an observer, its measured length in the direction of motion is contracted. t true?

Answer 1

That's true. It doesn't even need to be very high speed, although the effect is too small to measure at low speeds.

Answer 2

Your statement is not completely correct.
When an object is moving towards the observer, its measured wavelength decreases,(it is not correct if measured length) because the waves are compressed.