1. A digital video disk player using a digital video disk to store digital information including video data, audio data including speech, and closed caption data, comprising: a video player unit configured to extract the video data from the digital information, an audio player unit configured to read out the audio data to generate the audio signal, and a closed caption display controller, which is supplied with the audio signal, the closed caption display controller to control a display mode of a closed caption corresponding to a speech of an audio signal obtained by mixing the speech and a background sound or background music, the controller comprising, an analysis unit configured to analyze the audio signal to obtain a plurality of analysis values including a background level about the background sound or the background music, an examination unit configured to examine a difficulty in listening the speech by comparing the plurality of analysis values with a plurality of reference values including at least a reference value of the background level, and a determination unit configured to determine a display mode of the closed caption image according to an examination result of the examination unit.
1. A digital video disk player using a digital video disk to store digital information including video data, audio data including speech, and closed caption data, comprising: a video player unit configured to extract the video data from the digital information, an audio player unit configured to read out the audio data to generate the audio signal, and a closed caption display controller, which is supplied with the audio signal, the closed caption display controller to control a display mode of a closed caption corresponding to a speech of an audio signal obtained by mixing the speech and a background sound or background music, the controller comprising, an analysis unit configured to analyze the audio signal to obtain a plurality of analysis values including a background level about the background sound or the background music, an examination unit configured to examine a difficulty in listening the speech by comparing the plurality of analysis values with a plurality of reference values including at least a reference value of the background level, and a determination unit configured to determine a display mode of the closed caption image according to an examination result of the examination unit. 3. The digital video disk player according to claim 1 , which further includes a control signal input unit to input a playback control signal representing a playback sound volume of the speech or a playback speed thereof, and the examination unit is configured to examine the speech listening level according to one of a reference value of the playback sound volume and a reference value of the playback speed.