Image capturing apparatus, image processing apparatus and image processing method

Abstract

A digital camera which performs digital processing on an image obtained by image capturing has a three-dimensional lattice point data table for image data conversion processing. The digital camera holds a matrix coefficient set for performing the conversion processing by matrix operation. In the respective lattice points of the three-dimensional lattice point data table, values corresponding to the conversion processing with the matrix coefficient set are set. Then a raw image file, including compressed image data obtained by lossy compression on the image data converted by the conversion processing and the held matrix coefficient set, as attendant information, is generated.

Description

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to image processing in an image capturing apparatus such as a digital camera. [0003] 2. Description of the Related Art [0004] Generally, regarding image processing within digital cameras, in performing various conversion processing (for example, a gamma conversion) in, 3×3 matrix operation, a one-dimensional look-up table and the like are used. These conversion processings are appropriate for reducing the amount of hardware memory and gates in chip downsizing, and in scale reduction for energy saving. However, in recent years, advancement in hardware microminiaturization and reductions in IC power source voltage have allowed, chip size reductions and more effective energy savings to be realized. As a result, it is now possible to mount a complex circuit, a large capacity memory and the like within the IC. Accordingly, it is now becoming possible to perform complex image processing withi...

AI Technical Summary

Benefits of technology

The present invention provides an image capturing apparatus that uses a lattice point data table for image processing, reducing the necessary memory capacity for storing the table. The apparatus includes a conversion unit, a holding unit, and a setting unit. The conversion unit performs conversion processing on image data using the lattice point data table. The holding unit holds a matrix coefficient set for performing the conversion processing by matrix operation. The setting unit calculates values of respective lattice points of the lattice point data table using the matrix coefficient set and sets the values in the lattice point data table used by the conversion unit. This invention reduces the amount of memory needed for image processing, making it more efficient and cost-effective.

Problems solved by technology

However, in many cases, since the number of lattice points and bits are constrained by the hardware within the IC, high-precision image processing as in the case of application software cannot be performed.

As a result, the number of image frames that can be captured in a series is limited.

However, if all the data is generated using a look-up table for image processing with high bit precision, the data size of the look-up table becomes enormous, and the circuit scale increases.

Further, to perform image processing using high-order matrix operations for image processing with high bit precision, a large number of multipliers are required, and when the number of bits is increased, the gate scale increases markedly.

In actually, even when up to two-dimensional matrix operations are used, the level of freedom in image processing is limited with respect to processing using a three-dimensional lattice point data table.

In this case, a large amount of data of the three-dimensional lattice point data table, which is not used in image processing within the camera, must be stored in the ROM of the camera, and the efficiency of memory usage is seriously lowered.

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