Patent ID: 8442376

Claim:
An image data recording/playback device, comprising: a decoder that decodes image data encoded in a first format; and a transcoder configured to encode image data, supplied from the decoder and encoded in the first format, into a second format whose compression rate is higher than the compression rate of the first format and output the image data encoded into the second format to the decoder, decode input image data supplied from the decoder and encoded in the second format, output the decoded input image data to the decoder, and alternately carry out the encoding processing and the decoding processing, wherein: the decoder inputs/outputs image data encoded in the first and second format to/from a storage device; the transcoder employs a semi-duplex system capable of simultaneously carrying out only one of the processing in which image data encoded in the first format is encoded into the second format or the processing in which image data encoded in the second format is decoded; and the decoder simultaneously inputs image data encoded in the first format from the storage device when outputting image data encoded in the second format to the storage device, and the decoder simultaneously outputs image data encoded in the first format to the storage device when inputting image data encoded in the second format from the storage device.