Apple had filed the application on June 9, 2011 and before the release of the first HDR capable iPhone.
The patent application describes an image sensor and the HDR feature to take "two or more reads" of the sensor following an initial picture. "Data read out during these scans may be deinterleaved by an image signal processor and combined into a high dynamic range image," the document reads.
The process to generate a HDR picture Apple lays out is not different from the usual idea to combine characteristics of multiple picture into a single picture to achieve "greater dynamic range of luminances between the lightest and darkest areas of an image than standard digital imaging techniques". However, the company states that independently taken pictures may be slightly different due to hand movement/ Added HDR capability to an image sensor would be able to eliminate downsides that would cause the combination of pictures to be misaligned.
In detail, the application states: "To generate a HDR image during a single exposure of the frame (i.e., fixed amount of time t during which the rolling shutter reset moves across a frame), multiple reads of the same row of pixels of the image sensor may occur. For example, a first data read, of the data stored in a row of pixels, may be undertaken at a time n, where n is a fixed fractional time of time t. This time n may be, for example, 1/2, 1/3, 1/4, 1/5, 1/10, 1/20, or another value of the frame time t. This time n may be represented as line. That is, the first data read may occur at a time n subsequent to the reset of a row of pixels by the rolling shutter reset."
It is just a patent application at this time and we are not aware of any patents that may be collide with Apple's request. However, since HDR photography has been in the mainstream since the middle of the last decade, it would be highly unusual, if there was no prior art.
