Ultrasound scanner 2 obtains ultrasound frame data, which is compressed 30 before wireless transmission 32, e.g. via Wi-Fi, to a separate processor 4 for decompression 42 and image output, possibly to display screen 50 or goggles. The compression might be upon individual frames or lines within the frame data, possibly via a variable-length code (VLC) compressor encoding differences between consecutive ultrasound measurement portions. Since the compression does not rely on groups of frames, the transmission buffer, bandwidth or quality of service can be monitored and the frame compression adjusted accordingly, to give a reasonable latency. The number of scan positions or lines or the period between ultrasound frames might be regulated. A lag of just 70-90ms may be achieved. The separate scanner 2 or probe 3 may be useful in e.g. outdoor or veterinary environments. A regularly updated image can be displayed even if image quality may be temporarily reduced.
