When a switching target device receives a media output indication from a sender device, a switch (401) connects with contact B, which causes all image data stored in an extended media buffer (402) to be inputted in a decoder (201), starting from the first frame (which is an I-frame) of the image data. The decoder (201) decodes the image data, starting from the I-frame, and stores a reconstructed image in a reconstructed-image buffer (202). A reconstructed image required for decoding video picture data outputted from a media buffer (2108) is held in the reconstructed-image buffer (202). Thus, when device switching occurs, the decoder (201) can immediately start decoding regardless of whether video picture data inputted from the media buffer (2108) is an intraframe.