Video data transmission method for changing transmission data amounts in accordance with a transmission speed and a transmission system therefor

A motion picture transmission system comprising:

• a video transmission unit for encoding a motion picture signal;
• a transmission line for transmitting video data encoded in said video transmission unit;
• and
• a video reception unit for receiving said video data transmitted via said transmission line,
• wherein said video transmission unit includes generator for generating at least an I picture data and a plurality of P picture data, and
• selector for selecting said I picture data and a predetermined number of P picture data in accordance with a request from said transmission line.

A motion picture transmission apparatus comprising:

• a coding unit for converting a motion picture signal into at least I picture data and a plurality of P picture data;
• a memory unit for storing said I and P picture data;
• an output unit for outputting said I and P picture data;
• and
• a control unit for controlling said output unit,
• wherein said control unit controls the number of I picture data and the number of P picture data output from said output unit in accordance with a request from a transmission line.