Abstract: A transaction processing system includes a broadcasting station broadcasting a television signal and a teletext signal, the teletext signal including service information concerning transactions, a home-use terminal, a television set connected to the home-use terminal, a transaction processing center, and a communications network connecting the home-use terminal and the transaction processing center to each other.

Abstract: An image data processing apparatus capable of high-speed encoding even for intermittently supplied image data is provided with a memory storing image data, an encoder for encoding the image data and/or a decoder for decoding such encoded information and a transfer unit for DMA transfer of the image data from the memory to the encoder. A supply may be provided for supplying the encoder with the reference signals in synchronization with the DMA transfer of the image data by the transfer unit. The encoding and/or decoding are performed intermittently, e.g., in response to supply of the reference signals.

Abstract: An image signal coding apparatus includes reference and coding line change point detection circuits, reference line shift registers, a coding line shift register, a symbol detection circuit, coding and reference line ROM tables, and a code determination circuit. The coding line change point detection circuit receives a serial reference line image signal in synchronism with a serial coding line image signal. The reference line shift registers receive serial change point data in the reference line image signal and output parallel reference line change point data. The coding line shift register receives serial change point data in the coding line image signal and outputs parallel coding line change point data. The symbol detection circuit monitors output states of the reference and coding line shift registers. A run length counter counts the number of pixels between the change points in the coding line image signal.

Abstract: A decoder for two-dimensionally encoded image codes such as modified READ or modified READ codes ensures fast decoding operation by outputting reference codes in parallel while serially discriminating input codes and monitoring the relationship of both codes.