Methods, systems, and apparatuses are provided for measuring a display latency. A video capturing device is configured to capture a video of a reference light flash of a light emitter of a computing device. In the same video, the video capturing device is configured to capture a flash of a predetermined image displayed in a reference frame on a display screen coupled to the computing device. The video is analyzed to determine a time difference between the reference light flash of the light emitter and the flash of the predetermined image on the display screen. The determined time difference is compared with a reference time difference to determine a display latency, and the display latency may be provided to a user. In this manner, a display latency may be determined accurately and with readily available hardware, thus reducing the need to rely on expensive and specialized measuring equipment.

Methods, systems, and apparatuses are provided for measuring a display latency. A video capturing device is configured to capture a video of a reference light flash of a light emitter of a computing device. In the same video, the video capturing device is configured to capture a flash of a predetermined image displayed in a reference frame on a display screen coupled to the computing device. The video is analyzed to determine a time difference between the reference light flash of the light emitter and the flash of the predetermined image on the display screen. The determined time difference is compared with a reference time difference to determine a display latency, and the display latency may be provided to a user. In this manner, a display latency may be determined accurately and with readily available hardware, thus reducing the need to rely on expensive and specialized measuring equipment.

A camera module aligning method includes the following steps. Firstly, a reference chart having plural chart characteristic points is provided. Then, a camera module is used to shoot the reference chart, and an installation position and an installation posture of the camera module are acquired according to an internal parameter matrix and an external parameter matrix. When the camera module shoots the reference chart and an image is formed on an imaging plane of the camera module, a relationship between at least one image characteristic point of the image and the corresponding chart characteristic point complies with a standard relationship. The standard relationship is defined by the internal parameter matrix and the external parameter matrix.

A camera module aligning method includes the following steps. Firstly, a reference chart having plural chart characteristic points is provided. Then, a camera module is used to shoot the reference chart, and an installation position and an installation posture of the camera module are acquired according to an internal parameter matrix and an external parameter matrix. When the camera module shoots the reference chart and an image is formed on an imaging plane of the camera module, a relationship between at least one image characteristic point of the image and the corresponding chart characteristic point complies with a standard relationship. The standard relationship is defined by the internal parameter matrix and the external parameter matrix.

Disclosed is a method for automatically adjusting synchronization of sound and picture of TV. The method includes: obtaining a video, determining whether the video contains an adjustment video clip corresponding to a preset video database; obtaining audio information of the adjustment video clip and a time point corresponding to the audio information if the video contains the adjustment video clip corresponding to the preset video database; comparing the audio information of the adjustment video clip and the time point corresponding to the audio information with a standard video in the preset video database, and determining whether there is a synchronization delay between the sound and the picture; and synchronizing the sound and the picture of the video if there is the synchronization delay between the sound and the picture. A device for automatically adjusting synchronization of sound and picture of TV and a computer readable storage medium are further disclosed.

A residual DC measurement device of the present invention receives light emitted from a display device and outputs a light reception signal, measures a flicker value of the display device on the basis of the light reception signal output while the flicker measurement image is displayed by the display device and stores the flicker value in a storage as an initial flicker value, subsequently causes the display device to display a predetermined display image for a predetermined display time, causes the display device to display the flicker measurement image again when the predetermined display time elapses, measures the flicker value of the display device on the basis of the light reception signal output while the flicker measurement image is displayed and stores the flicker value in the storage as a posterior flicker value, and calculates a flicker change amount by calculating the posterior flicker value stored in the storage and the initial flicker value as an index value representing the residual DC.

A method for calibrating a wearable device includes displaying an image with a plurality of pixels for each of three primary colors using the wearable device, and determining RGB and XYZ values for each of the plurality of pixels. The method includes selecting a subset of the plurality of pixels to form a group of grid points, and dividing the image into a group of tile regions, with each tile region including a grid point. Grid XYZ values are determined for each grid point, based on averaging XYZ values of all pixels in a corresponding tile region, and a grid RGB-to-XYZ conversion matrix is determined for each grid point. The method also includes determining a correction matrix for each grid point by multiplying an inverse of the grid RGB-to-XYZ conversion matrix for the grid with an sRGB-to-XYZ conversion matrix.

A method for calibrating a wearable device includes displaying an image with a plurality of pixels for each of three primary colors using the wearable device, and determining RGB and XYZ values for each of the plurality of pixels. The method includes selecting a subset of the plurality of pixels to form a group of grid points, and dividing the image into a group of tile regions, with each tile region including a grid point. Grid XYZ values are determined for each grid point, based on averaging XYZ values of all pixels in a corresponding tile region, and a grid RGB-to-XYZ conversion matrix is determined for each grid point. The method also includes determining a correction matrix for each grid point by multiplying an inverse of the grid RGB-to-XYZ conversion matrix for the grid with an sRGB-to-XYZ conversion matrix.

A video processing device includes: a frame number generating unit that generates frame numbers representing respective frames to which successively supplied video data belongs, the frame numbers differing between one frame and a next frame; a writing unit that writes a data block including a piece of the video data and the frame number corresponding thereto in a frame memory for every frame; a reading unit that reads out the data block written in the frame memory in the order of frames; and a video freezing determination unit that generates an abnormality determination signal that indicates video freezing when a current value of the frame number of the data block read stays the same as a previous value over a prescribed number of times.

A video processing device includes: a frame number generating unit that generates frame numbers representing respective frames to which successively supplied video data belongs, the frame numbers differing between one frame and a next frame; a writing unit that writes a data block including a piece of the video data and the frame number corresponding thereto in a frame memory for every frame; a reading unit that reads out the data block written in the frame memory in the order of frames; and a video freezing determination unit that generates an abnormality determination signal that indicates video freezing when a current value of the frame number of the data block read stays the same as a previous value over a prescribed number of times.