Electronic shelf label system with sectional control of display content

An electronic shelf label system (1), comprising a number of display devices (6A, 6B) to display content on its screen or its screens (5A-5D), each device (6A, 6B) comprises

• a memory stage (13) to store content data, and
• a control stage (15) to control the display of the content on its screen (5A-5D), wherein
• the screen (5A-5D) is a video screen and realizes a shelf rail (4) or covers a front of a shelf rail (4) or a part of it to which it is attachable, and
• the content is a video and the memory stage (13) stores the video data of the video, and
• the control stage (15) is designed to define a display window (W1-W4) for the video and to display video content within the display window (W1-W4) on its screen (5A-5D),
• wherein a coordinated playback of the video on a number of screens (5A-5D) is provided and each screen (5A-5D) shows the video content of an individual display window (W1-W4), and wherein
• the devices (6A, 6B) are designed to playback compressed video data that are structured in frames labeled by frame numbers,
• the devices (6A, 6B) are designed to utilize a frame number that labels the frame that is currently played back as a progress-data to be transmitted in the group of devices (6A, 6B) playing the same video,
• the devices (6A, 6B) are designed to transmit the progress-data repeatedly, in particular in aperiodic manner, and
• each device (6A, 6B) is further designed to
• compare a frame number received with a frame number of the frame currently played back at the device (6A, 6B) and
• to determine an asynchronous playback progress when the difference in the frame numbers compared with each other exceeds a pre-determined threshold value and to send out the higher of the two compared frame numbers, and
• to continue their playback with this higher of the two compared frame numbers.