An image transmission process allows fixed data rates to be efficiently utilised. The image data to be transmitted are sorted into different categories depending on their sensitivity to channel errors and the categories are provided with different error protections and transmitted. Information words that contain information on the number of data bits belonging to the category and the type of error protection used precede the individual categories. In addition, a synchronisation word is added to the image data of each image. At the receiver, the first information words are channel-decoded according to a fixed coding rate and the information stored in the first information words is used for channel-decoding the image data. The image data are then image source decoded and outputted.