Abstract: An electronic device may include a display, an ambient light sensor, and control circuitry. The control circuitry may use a mesopic vision model to compensate images that are displayed in low light conditions when the measured ambient light brightness is below a threshold. The mesopic vision model may use a tone mapping process and a color mapping process to compensate for the reduced color sensitivity of the retina in low light conditions. The control circuitry may iteratively adjust weights associated with the tone mapping process and the color mapping process until a perceived (retinal) version of the compensated image in the measured ambient light conditions closely matches a perceived (retinal) version of the original image in reference ambient light conditions. The control circuitry may use a joint optimization process that balances the contrast and color of the compensated image.

Abstract: A system may include multiple electronic devices. A first device such as a source electronic device may supply visual content for displaying by a display in a second electronic device such as a display electronic device. The display electronic device may be a television or other device with a display. Calibration operations may be performed by taking light measurements on light produced by the display when test content is provided from the first device to the second device. A third electronic device in the system such as a portable electronic device with an ambient light sensor may make measurement on the light from the display while the test content is being displayed. The test content may contain a test image target with time-varying color and time-varying intensity, allowing calibration information such as gamma curves to be obtained on the display.

Abstract: In some implementations, a mobile computing device may participate in the calibration of an output signal of a media device. This calibration process includes storing device-specific calibration data which is related to properties of a light sensor of the mobile device. The mobile device then detects of properties of light emitted by the display device during a presentation to obtain sensor values related to light emitted by the display device during the presentation. The calibration process may also ensure that the mobile device is proximate to the display device prior to obtaining the sensor values. The collected sensor values are adjusted using device-specific calibration data stored to the mobile device to normalize the sensor values relative to a baseline. These normalized sensor values are sent to the media device for use in adjusting the output signal based on the normalized sensor values.

Abstract: In some implementations, a mobile computing device may participate in the calibration of an output signal of a media device. This calibration process includes storing device-specific calibration data which is related to properties of a light sensor of the mobile device. The mobile device then detects of properties of light emitted by the display device during a presentation to obtain sensor values related to light emitted by the display device during the presentation. The calibration process may also ensure that the mobile device is proximate to the display device prior to obtaining the sensor values. The collected sensor values are adjusted using device-specific calibration data stored to the mobile device to normalize the sensor values relative to a baseline. These normalized sensor values are sent to the media device for use in adjusting the output signal based on the normalized sensor values.

Abstract: In some implementations, a mobile computing device may participate in the calibration of an output signal of a media device. This calibration process includes storing device-specific calibration data which is related to properties of a light sensor of the mobile device. The mobile device then detects of properties of light emitted by the display device during a presentation to obtain sensor values related to light emitted by the display device during the presentation. The calibration process may also ensure that the mobile device is proximate to the display device prior to obtaining the sensor values. The collected sensor values are adjusted using device-specific calibration data stored to the mobile device to normalize the sensor values relative to a baseline. These normalized sensor values are sent to the media device for use in adjusting the output signal based on the normalized sensor values.

Abstract: In some implementations, a mobile computing device may participate in the calibration of an output signal of a media device. This calibration process includes storing device-specific calibration data which is related to properties of a light sensor of the mobile device. The mobile device then detects of properties of light emitted by the display device during a presentation to obtain sensor values related to light emitted by the display device during the presentation. The calibration process may also ensure that the mobile device is proximate to the display device prior to obtaining the sensor values. The collected sensor values are adjusted using device-specific calibration data stored to the mobile device to normalize the sensor values relative to a baseline. These normalized sensor values are sent to the media device for use in adjusting the output signal based on the normalized sensor values.