A system for transmitting and receiving an image signal has transmission apparatuses and reception apparatuses. Each of the transmission apparatuses includes an image pickup device for alternately outputting first and second image signals obtained by picking up images of a subject with different exposure times, a compressor for separately compressing data amounts of the first and second image signals, and a transmission interface for attaching an identification signal for identification of a transmitter and a frame number to each of compressed first and second image signals and transmitting attached compressed signals to a signal path. Each of the reception apparatuses includes a reception interface for receiving from the signal path the compressed image signals, an expander for individually expanding the received compressed image signals to reproduce the first and second image signals, and a combiner for combining reproduced first and second image signals at a desired combination ratio.