Apple has been granted five camera related patents today by the US Patent and Trademark office. The patents range from a dual sensor processing system to improving auto exposure.

The first is a dual sensor image processing patent which looks to improve on the quality of images by processing data from multiple sensors in order to reduce photographic anomalies.

Various techniques are provided for processing image data acquired using a digital image sensor. In accordance with aspects of the present disclosure, one such technique may relate to the processing of image data in a system that supports multiple image sensors. In one embodiment, the image processing system may include control circuitry configured to determine whether a device is operating in a single sensor mode (one active sensor) or a dual sensor mode (two active sensors). When operating in the single sensor mode, data may be provided directly to a front-end pixel processing unit from the sensor interface of the active sensor. When operating in a dual sensor mode, the image frames from the first and second sensors are provided to the front-end pixel processing unit in an interleaved manner. For instance, in one embodiment, the image frames from the first and second sensors are written to a memory, and then read out to the front-end pixel processing unit in an interleaved manner.



Apple also was granted a patent for a System and method for RAW image processing. Filed back in July of 2010, the patent discloses an automated RAW image processing system within the OS.

An automated RAW image processing method and system are disclosed. A RAW image and metadata related to the RAW image are obtained from a digital camera or other source. The RAW image and the related metadata are automatically processed using an Operating System service of a processing device to produce a resulting image in an absolute color space. The resulting image is then made available to an application program executing on the processing device through an application program interface with the Operating System service.

The office also granted Apple the 'Image capturing devices using orientation detectors to implement automatic exposure mechanisms' patent which describes various ways to implement auto exposures mechanisms for cameras.

The automatic exposure mechanism projects an orientation vector into an image plane of an image sensor. Next, the automatic exposure mechanism adjusts an initial position of a metering area used for automatic exposure towards a target position based on the projected orientation vector. The automatic exposure mechanism optionally dampens the adjustment of the metering area.



Apple was also granted two other patents relating to auto-exposure. The first was 'scene-aware' which stabilizes the camera's auto exposure to reduce lighting and color flicking. However scene changes such as moving into or out of a scene do not cause a trigger to exposure adjustments.

A metric, referred to as the Modified Adjusted Luminance (MAL) metric, is defined to remain relatively constant as long as the lighting of the scene being captured remains relatively constant. Thus, scene changes such as an object moving into, out of, or around in a scene do not significantly affect the MAL metric's value and do not, therefore, trigger an exposure adjustment.

The other auto-exposure patent was related to 'blowout' prevention. A blow is an area in an image where the pixel brightness exceeds the sensor's capturing capability.

In one embodiment, the captured image's histogram may be analyzed to determine if the image is indicative of the presence of exposure blowouts. Once it has been determined that there likely are blowouts in the image, an exposure bias for the image capture device may be set accordingly.