Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for generating and decoding watermarks. An image and a data item is received. The encoder generates a first watermark and then a second watermark is generated using multiple first watermarks. The second watermark is used to watermark the image by overlaying the second watermark over the image. To decode the watermark, presence of a watermark is determined on a portion of an image. A distortion model determines distortions in the image and modifies the portion of the image based on the predicted distortions. The modified portion is decoded using the decoder to obtain a predicted first data item that is further used to validate the watermark based on the first data item.

Abstract: A display panel includes a data line, a pixel driving circuit, a light-emitting device and a voltage compensation circuit. The voltage compensation circuit includes a sampling and conditioning unit configured to obtain a driving current output by the pixel driving circuit and to output a control signal according to the driving current; a first switch unit including a control terminal, an input terminal and an output terminal, the control terminal of the first switch unit being connected to an output terminal of the sampling and conditioning unit, and the input terminal of the first switch unit being connected to the output terminal of the pixel driving circuit; a compensation unit including an input terminal and an output terminal, the input terminal of the compensation unit being connected to the output terminal of the first switch unit, and the output terminal of the compensation unit being connected to the data line.

Abstract: A display panel includes a data line, a pixel driving circuit, a light-emitting device and a voltage compensation circuit. The voltage compensation circuit includes a sampling and conditioning unit configured to obtain a driving current output by the pixel driving circuit and to output a control signal according to the driving current; a first switch unit including a control terminal, an input terminal and an output terminal, the control terminal of the first switch unit being connected to an output terminal of the sampling and conditioning unit, and the input terminal of the first switch unit being connected to the output terminal of the pixel driving circuit; a compensation unit including an input terminal and an output terminal, the input terminal of the compensation unit being connected to the output terminal of the first switch unit, and the output terminal of the compensation unit being connected to the data line.