Abstract: A display device may include a display panel including a first display area having a plurality of first pixels and a second display having a plurality of second pixels and a light-transmission area between the second pixels. The display device may further include a sensor or an optical element under the display panel and overlapping with the second display area of the display panel. The display panel may include a substrate, a circuit layer on the substrate and having a buffer layer and a plurality of insulating layers, and a light emitting element layer on the circuit layer. The second display area may include a hole penetrating the substrate, the buffer layer, and the plurality of insulating layers.

Abstract: Provided is an image processing device configured to compress first image data. The image processing device includes an encoding circuit configured to compress the first image data into second image data including prediction data and residual data, compress the second image data into third image data by performing entropy encoding on the second image data, generate a header representing a compression ratio of the third image data, and store the third image data along with the header in a memory device as compressed first image data.

Abstract: In a system for transmitting a data file, a first terminal calculates sizes of data fields for a displayed target data file on a frame basis, totals the calculated sizes, code-converts a data file having the totaled size, and encodes the code-converted data file, and a second terminal captures the target data file displayed on the first terminal using a camera at N frames-per-second (fps) (where N is an integer), and decodes the captured data file.

Abstract: A letter input method and system for inputting a sequence of letters are provided. The letter input method includes activating a toggle input mode in response to a stroke on one of toggle keys, detecting an input event on a letter key in the toggle input mode, and inputting a letter which is fixed to the letter key in association with the toggle key activated in the toggle input mode among multiple letters assigned to letter keys.