Gain calling system and method

Abstract

The present invention provides a gain calling system, comprising an image processing chip and an image processing auxiliary module, wherein the image processing chip comprises a lens shading correction unit, a cache unit, an on-chip storage unit, an on-chip storage control unit and an off-chip storage control unit, and the image processing auxiliary module comprises an off-chip storage unit, wherein all block point gain values ​​are uniformly stored through the off-chip storage unit, and when the lens shading correction unit performs lens shading correction processing on an image, the off-chip storage control unit retrieves the corresponding block point gain value from the off-chip storage unit and transmits it to the on-chip storage control unit, and then the on-chip storage control unit writes the on-chip storage unit, and then the on-chip storage control unit reads the on-chip storage unit and writes the cache unit, thereby greatly reducing the memory size of the on-chip storage unit, thereby reducing the area of ​​the image processing chip. The present invention also provides a gain calling method.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor chip technology, and in particular to a gain calling system and method. Background Art

[0002] Lens shading is a phenomenon of uneven image brightness caused by the optical characteristics of the lens. Currently, the grid method is used to implement Lens Shading Correction (LSC). The grid method is to divide the image into grids, and use the block point gain values ​​of the four corners of the corresponding grids to perform bilinear interpolation correction on the pixels in different grids. The gain value is obtained by testing and is generally written into the chip in advance. It is automatically retrieved and used when the module is turned on. The storage and reading of the gain value can be implemented in different ways inside the chip, such as storing it in a register or storing it in a static random access memory (SRAM).

[0003] When performing LSC correction on images with different color channels, the number of gain values ​​that need to be stored is three times that of images with no color channels. If all of them are stored inside the image processing chip, the area of ​​the image processing chip will be greatly increased.

[0004] Therefore, it is necessary to provide a new gain calling system and method to solve the above problems existing in the prior art. Summary of the invention

[0005] The object of the present invention is to provide a gain calling system and method to reduce the area of ​​an image processing chip.

[0006] To achieve the above-mentioned purpose, the gain calling system of the present invention comprises an image processing chip and an image processing auxiliary module, wherein the image processing chip comprises a lens shading correction unit, a cache unit, an on-chip storage unit, an on-chip storage control unit and an off-chip storage control unit, wherein the lens shading correction unit is connected to the cache unit, the on-chip storage control unit is connected to the on-chip storage unit and the off-chip storage control unit, the image processing auxiliary module comprises an off-chip storage unit, and the off-chip storage control unit is connected to the off-chip storage unit.

[0007] Among them, the lens shading correction unit is used to perform lens shading correction processing on the image; the off-chip storage unit is used to store all block point gain values; the off-chip storage control unit is used to write all the block point gain values ​​into the off-chip storage unit, and read part of the block point gain values ​​from the off-chip storage unit and transmit them to the on-chip storage control unit; the on-chip storage unit is used to store part of the block point gain values; the on-chip storage control unit is used to write part of the block point gain values ​​into the on-chip storage unit, and read the block point gain values ​​from the on-chip storage unit and write them into the cache unit.

[0008] The beneficial effect of the gain calling system is that all block point gain values ​​are uniformly stored through the off-chip storage unit, and when the lens shading correction unit performs lens shading correction processing on the image, the off-chip storage control unit retrieves the corresponding block point gain value from the off-chip storage unit and transmits it to the on-chip storage control unit, which is then written into the on-chip storage unit by the on-chip storage control unit, and then reads from the on-chip storage unit and writes into the cache unit through the on-chip storage control unit, which can greatly reduce the memory size of the on-chip storage unit, thereby reducing the area of ​​the image processing chip.

[0009] Optionally, the on-chip storage unit is a volatile memory, the off-chip storage unit is a non-volatile memory, and the cache unit is an asynchronous first-in-first-out memory.

[0010] Optionally, the image processing auxiliary module further includes a bus unit and a processor, and the bus unit is connected to the processor and the off-chip storage control unit.

[0011] Optionally, the off-chip storage control unit is used to read from the off-chip storage unit a block point gain value required for the lens shading correction unit to perform lens shading correction processing on a row of image data.

[0012] Optionally, the on-chip storage control unit is used to write the block point gain value required by the lens shading correction unit to perform lens shading correction processing on a row of image data into the on-chip storage unit.

[0013] Optionally, the on-chip storage unit is used to store block point gain values ​​required for the lens shading correction unit to perform lens shading correction processing on a row of image data.

[0014] The present invention also provides a gain calling method, comprising:

[0015] A gain calling system is provided, comprising an image processing chip and an image processing auxiliary module, wherein the image processing chip comprises a lens shading correction unit, a cache unit, an on-chip storage unit, an on-chip storage control unit and an off-chip storage control unit, wherein the lens shading correction unit is connected to the cache unit, the on-chip storage control unit is connected to the on-chip storage unit and the off-chip storage control unit, the image processing auxiliary module comprises an off-chip storage unit, and the off-chip storage control unit is connected to the off-chip storage unit;

[0016] The off-chip storage control unit writes all the block point gain values ​​into the off-chip storage unit;

[0017] The off-chip storage control unit reads part of the block point gain value from the off-chip storage unit and transmits it to the on-chip storage control unit;

[0018] The on-chip storage control unit writes part of the block point gain values ​​into the on-chip storage unit;

[0019] The on-chip storage control unit reads the block point gain value from the on-chip storage unit and writes it into the cache unit;

[0020] The cache unit transmits the block point gain value to the lens shading correction unit according to the request of the lens shading correction unit.

[0021] The beneficial effect of the gain calling method is that: the off-chip storage control unit writes all the block point gain values ​​into the off-chip storage unit, the off-chip storage control unit reads part of the block point gain values ​​from the off-chip storage unit and transmits them to the on-chip storage control unit, the on-chip storage control unit writes part of the block point gain values ​​into the on-chip storage unit, the on-chip storage control unit reads the block point gain values ​​from the on-chip storage unit and writes them into the cache unit, and the cache unit transmits the block point gain values ​​to the lens shading correction unit according to the request of the lens shading correction unit, which can greatly reduce the memory size of the on-chip storage unit, thereby reducing the area of ​​the image processing chip.

[0022] Optionally, the off-chip storage control unit reads part of the block point gain values ​​from the off-chip storage unit and transmits them to the on-chip storage control unit, including:

[0023] The off-chip storage control unit reads the block point gain value required by the lens shading correction unit to perform lens shading correction processing on a row of image data from the off-chip storage unit and transmits it to the on-chip storage control unit.

[0024] Optionally, the on-chip storage control unit writes part of the block point gain values ​​into the on-chip storage unit, including:

[0025] The on-chip storage control unit writes the block point gain value required by the lens shading correction unit to perform lens shading correction processing on a row of image data into the on-chip storage unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A structural block diagram of a gain calling system in some embodiments of the present invention;

[0027] Figure 2 A flowchart of a gain calling method in some embodiments of the present invention;

[0028] Figure 3 A schematic diagram of grid differentiation of an image in some embodiments of the present invention;

[0029] Figure 4 1 is a waveform diagram of the access sequence of the block point gain values ​​in some embodiments of the present invention. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be understood by people with general skills in the field to which the present invention belongs. "Including" and similar words used in this article mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0031] In view of the problems existing in the prior art, an embodiment of the present invention provides a gain calling system. Figure 1 The gain calling system includes an image processing chip 101 and an image processing auxiliary module. The image processing chip 101 includes a lens shading correction unit 1011, a cache unit 1012, an on-chip storage unit 1013, an on-chip storage control unit 1014 and an off-chip storage control unit 1015. The lens shading correction unit 1011 is connected to the cache unit 1012, the on-chip storage control unit 1014 is connected to the on-chip storage unit 1013 and the off-chip storage control unit 1015, the image processing auxiliary module includes an off-chip storage unit 102, and the off-chip storage control unit 1015 is connected to the off-chip storage unit 102.

[0032] Among them, the lens shading correction unit 1011 is used to perform lens shading correction processing on the image; the off-chip storage unit 102 is used to store all block point gain values; the off-chip storage control unit 1015 is used to write all the block point gain values ​​into the off-chip storage unit 102, and read part of the block point gain values ​​from the off-chip storage unit 102 and transmit them to the on-chip storage control unit 1014; the on-chip storage unit 1013 is used to store part of the block point gain values; the on-chip storage control unit 1014 is used to write part of the block point gain values ​​into the on-chip storage unit 1013, and read the block point gain values ​​from the on-chip storage unit 1013 and write them into the cache unit 1012.

[0033] In some embodiments, the on-chip storage unit is a volatile memory, the off-chip storage unit is a non-volatile memory, and the cache unit is an asynchronous first-input-first-out memory (FIFO). Specifically, the on-chip storage unit is a static random-access memory (SRAM), and the off-chip storage unit is a Flash memory.

[0034] Reference Figure 1 The connection interface between the off-chip storage control unit 1015 and the static random access memory is a spi interface, which greatly improves the communication efficiency between the off-chip storage control unit 1015 and the static random access memory.

[0035] Reference Figure 1 The image processing auxiliary module further includes a bus unit 103 and a processor 104, wherein the bus unit 103 is connected to the processor 104 and the off-chip storage control unit 1015. Specifically, the bus unit 103 includes an arbitrator and a bus, wherein the bus includes at least one of an APB bus, an AHB bus, and an AXI bus, and the processor includes a microcontroller unit (MCU).

[0036] In some embodiments, the off-chip storage control unit is used to read the block point gain value required by the lens shading correction unit to perform lens shading correction processing on a row of image data from the off-chip storage unit; and is also used to write the block point gain value required by the lens shading correction unit to perform lens shading correction processing on a row of image data into the on-chip storage unit. The on-chip storage unit is used to store the block point gain value required by the lens shading correction unit to perform lens shading correction processing on a row of image data.

[0037] Figure 2FIG. 1 is a flow chart of a gain calling method in some embodiments of the present invention. Figure 2 , the gain calling method comprises the following steps:

[0038] S0: A gain calling system is provided, comprising an image processing chip and an image processing auxiliary module, wherein the image processing chip comprises a lens shading correction unit, a cache unit, an on-chip storage unit, an on-chip storage control unit and an off-chip storage control unit, wherein the lens shading correction unit is connected to the cache unit, the on-chip storage control unit is connected to the on-chip storage unit and the off-chip storage control unit, the image processing auxiliary module comprises an off-chip storage unit, and the off-chip storage control unit is connected to the off-chip storage unit;

[0039] S1: the off-chip storage control unit writes all the block point gain values ​​into the off-chip storage unit;

[0040] S2: the off-chip storage control unit reads part of the block point gain value from the off-chip storage unit and transmits it to the on-chip storage control unit;

[0041] S3: the on-chip storage control unit writes part of the block point gain values ​​into the on-chip storage unit;

[0042] S4: the on-chip storage control unit reads the block point gain value from the on-chip storage unit and writes it into the cache unit;

[0043] S5: The cache unit transmits the block point gain value to the lens shading correction unit according to the request of the lens shading correction unit.

[0044] In some embodiments, the off-chip storage control unit reads part of the block point gain values ​​from the off-chip storage unit and transmits them to the on-chip storage control unit, including: the off-chip storage control unit reads the block point gain values ​​required for the lens shading correction unit to perform lens shading correction processing on a row of image data from the off-chip storage unit and transmits them to the on-chip storage control unit.

[0045] In some embodiments, the on-chip storage control unit writes part of the block point gain values ​​into the on-chip storage unit, including: the on-chip storage control unit writes the block point gain values ​​required by the lens shading correction unit to perform lens shading correction processing on a row of image data into the on-chip storage unit.

[0046] Figure 3 Schematic diagram of grid differentiation of an image in some embodiments of the present invention. Figure 3, a frame of image is divided into small grids, the values ​​at the four corners of each grid are the block point gain values, and the pixels in each grid are corrected according to the four block point gain values. Among them, block0 represents the 0th grid, block1 represents the 1st grid, and so on, blocklast represents the last grid; line0 represents the 0th row of pixels, and line1 represents the 1st row of pixels. The four block point gain values ​​of the 0th grid are (1, 0), (0, 0), (1, 1) and (0, 1), and the four block point gain values ​​of the 1st grid are (1, 1), (0, 1), (1, 2) and (0, 2).

[0047] Figure 4 The following is a waveform diagram of the access sequence of the block point gain value in some embodiments of the present invention. Figure 4 In the figure, vsync is the frame synchronization signal and hsync is the line synchronization signal.

[0048] Reference Figure 1 , Figure 3 and Figure 4 When correcting the pixels in the 0th row, the lens shading correction unit 1011 sends a read request signal inter_rd to the cache unit 1013 to read data inter from the cache unit 1013, that is, loads block point gain values ​​(1, 0), (0, 0), (1, 1) and (0, 1), and performs lens shading correction on the pixels in the 0th row in block0; when the pixels to be corrected change from block0 to block1, the lens shading correction unit 1011 loads two new block point gain values ​​(1, 2) and (0, 2). Because the two block point gain values ​​(1, 1) and (0, 1) have been loaded when correcting the pixels in the 0th row in block0, there is no need to repeatedly load the two block point gain values ​​(1, 1) and (0, 1) when correcting the pixels in the 0th row in block1; the gain value loading method of subsequent grids is the same, which will not be repeated here.

[0049] Reference Figure 1 , Figure 3 and Figure 4 When correcting the pixels of the first row, the lens shading correction unit 1011 needs to reload the block point gain values ​​(1, 0), (0, 0), (1, 1) and (0, 1). The subsequent loading method of the block gain points is the same as the method of correcting the pixels of the 0th row, which will not be repeated here.

[0050] Reference Figure 1 , Figure 3 and Figure 4When the pixel correction of one frame of image is completed and the pixel correction of another frame of image is started, the grid jumps from blocklast to block0, and the lens shading correction unit 1011 needs to reload the block point gain values ​​(1, 0), (0, 0), (1, 1) and (0, 1). The subsequent loading method of the block gain points is the same as the method of correcting the pixel points of the previous frame of image, which will not be repeated here.

[0051] Reference Figure 1 , Figure 3 and Figure 4 , before the pixel correction of each frame image and before the correction of each row of pixels begins, there is a row blanking (hblank) and a field blanking (vblank). During the row blanking (hblank) or the field blanking (vblank), the off-chip storage control unit 1015 reads all the block point gain values ​​required for the lens shading correction of the current row of pixels from the off-chip storage unit, and transmits them to the on-chip storage control unit 1014, and then the on-chip storage control unit 1014 writes them into the on-chip storage unit 1013. Then the on-chip storage control unit 1014 reads all the block point gain values ​​required for the lens shading correction of the current row of pixels from the on-chip storage unit 1013, and writes them into the cache unit, and finally the lens shading correction unit 1011 loads the block point gain values ​​from the cache unit in sequence.

[0052] Although the embodiments of the present invention are described in detail above, it is obvious to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations are within the scope and spirit of the present invention as described in the claims. Moreover, the present invention described herein may have other embodiments and may be implemented or realized in a variety of ways.

Claims

1. A gain calling system, characterized in that: The invention comprises an image processing chip and an image processing auxiliary module, wherein the image processing chip comprises a lens shading correction unit, a cache unit, an on-chip storage unit, an on-chip storage control unit and an off-chip storage control unit, wherein the lens shading correction unit is connected to the cache unit, the on-chip storage control unit is connected to the on-chip storage unit and the off-chip storage control unit, the image processing auxiliary module comprises an off-chip storage unit, and the off-chip storage control unit is connected to the off-chip storage unit. Among them, the lens shading correction unit is used to perform lens shading correction processing on the image; the off-chip storage unit is used to store all block point gain values; the off-chip storage control unit is used to write all the block point gain values ​​into the off-chip storage unit, and read part of the block point gain values ​​from the off-chip storage unit and transmit them to the on-chip storage control unit, which is specifically used to read the block point gain values ​​required by the lens shading correction unit to perform lens shading correction processing on a row of image data from the off-chip storage unit; the on-chip storage unit is used to store part of the block point gain values, which is specifically used to store the block point gain values ​​required by the lens shading correction unit to perform lens shading correction processing on a row of image data; the on-chip storage control unit is used to write part of the block point gain values ​​into the on-chip storage unit, and read the block point gain values ​​from the on-chip storage unit and write them into the cache unit, which is specifically used to write the block point gain values ​​required by the lens shading correction unit to perform lens shading correction processing on a row of image data into the on-chip storage unit.

2. The gain calling system according to claim 1, characterized in that: The on-chip storage unit is a volatile memory, the off-chip storage unit is a non-volatile memory, and the cache unit is an asynchronous first-in-first-out memory.

3. The gain calling system according to claim 1, characterized in that: The image processing auxiliary module further includes a bus unit and a processor, wherein the bus unit is connected to the processor and the off-chip storage control unit.

4. A gain calling method, applied to the gain calling system according to any one of claims 1 to 3, characterized in that: The gain calling method comprises: The off-chip storage control unit writes all the block point gain values ​​into the off-chip storage unit; The off-chip storage control unit reads part of the block point gain values ​​from the off-chip storage unit and transmits them to the on-chip storage control unit, which includes: the off-chip storage control unit reads the block point gain values ​​required for the lens shading correction unit to perform lens shading correction processing on a row of image data from the off-chip storage unit and transmits them to the on-chip storage control unit; The on-chip storage control unit writes part of the block point gain values ​​into the on-chip storage unit, which includes: the on-chip storage control unit writes the block point gain values ​​required for the lens shading correction unit to perform lens shading correction processing on a row of image data into the on-chip storage unit; The on-chip storage control unit reads the block point gain value from the on-chip storage unit and writes it into the cache unit; The cache unit transmits the block point gain value to the lens shading correction unit according to the request of the lens shading correction unit.

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