Abstract: Imaging systems with image sensors and image processing circuitry are provided. The image processing circuitry may calculate sharpness values for a window within an image captured by the image sensors. The window may be divided into zones. A first filter may be applied to each row of each zone. A first sharpness value may be calculated by averaging the absolute values of the outputs of the first filter that are greater than a first threshold. A second sharpness value may be calculated by averaging the absolute values of the outputs of the second filter that are greater than a second threshold. A final sharpness value for each zone may be calculated by dividing the second sharpness value by the first sharpness value and multiplying the result by corresponding scalar weights. A window sharpness value may be calculated from the weighted sum of the final sharpness values of each zone.

Abstract: Electronic devices may have camera modules that include an image sensor and processing circuitry. The image sensor may capture an interleaved image having rows of long-exposure pixel values that are interleaved with rows of short-exposure pixel values. The image sensor may separate the interleaved image into first and second images each having empty image pixel values. The processing circuitry may generate interpolated long-exposure and interpolated short-exposure images by generating chroma-filtered interpolated pixel values for the empty pixel values in the first and second images. The processing circuitry may perform interpolation operations along one or more directions for the empty image pixels based on whether the empty image pixels are within a texture area or on a dominant edge of the captured image. The processing circuitry may combine the interpolated long-exposure image and the interpolated short-exposure image to generate a high-dynamic-range image.

Abstract: Imaging systems with image sensors and image processing circuitry are provided. The image processing circuitry may calculate sharpness values for a window within an image captured by the image sensors. The window may be divided into zones. A first filter may be applied to each row of each zone. A first sharpness value may be calculated by averaging the absolute values of the outputs of the first filter that are greater than a first threshold. A second sharpness value may be calculated by averaging the absolute values of the outputs of the second filter that are greater than a second threshold. A final sharpness value for each zone may be calculated by dividing the second sharpness value by the first sharpness value and multiplying the result by corresponding scalar weights. A window sharpness value may be calculated from the weighted sum of the final sharpness values of each zone.