| 摘要 |
A VIDEO DECODER (121) COMPLIANT WITH THE ADVANCED TELEVISION SYSTEMS STANDARD (ATSC) INCLUDES CIRCUITRY (210, 212, 214, 218, 230) WHICH, WHEN THE DECODER IS OPERATED IN A FIRST MODE, DECODES A MAIN PROFILE, HIGH LEVEL (MP@HL) IMAGE TO PRODUCE A HIGH-DEFINITION VIDEO OUTPUT SIGNAL AND DECODES A MAIN PROFILE, MAIN LEVEL (MP@ML) SIGNAL TO PRODUCE A STANDARD DEFINITION VIDEO SIGNAL. IN ADDITION, WHEN THE DECODER (121) IS OPERATED IN A SECOND MODE, CIRCUITRY (216, 232) IS USED WHICH GENERATES A STANDARD DEFINITION IMAGE FROM THE MP@HL SIGNAL. THE VIDEO DECODER INCLUDES A FREQUENCY-DOMAIN FILTER (216) TO REDUCE THE RESOLUTION OF THE MP@HL SIGNAL WHEN THE DECODER IS OPERATED IN THE SECOND MODE. |
