JP2021011095A - Image processing device, image processing method, and program - Google Patents

Abstract

To preform image processing without increasing a scale of a memory.SOLUTION: An image processing device according to one aspect of a disclosed technology includes: a length-width conversion processing part which outputs first image data, to which length-width conversion has been performed, to a storage part; an image processing part which outputs second image data, which is obtained by performing predetermined image processing to the first image data, to the storage part; and a rendering processing part which outputs third image data, which is obtained by performing rendering to the second image data, to the storage part.SELECTED DRAWING: Figure 5

Description

The present application relates to an image processing apparatus, an image processing method, and a program.

Conventionally, a liquid discharge device that discharges a liquid based on image data and prints it on a recording medium is known. Further, the liquid discharge device includes a liquid discharge head including a nozzle array in which nozzles for discharging liquid are arranged along the transport direction of the recording medium, and scans the liquid discharge head in the main scanning direction orthogonal to the transport direction. It is known that printing of a plurality of lines is collectively executed by making the printing.

In such a liquid discharge device, a process of rearranging the image data according to the position of the liquid discharge head is performed, and the image data is output to a memory provided in the liquid discharge device according to a continuous address in the main scanning direction from the upper left of the image. Will be done. On the other hand, as described above, the liquid discharge head collectively prints a plurality of lines in the transport direction, so that the image data is arranged 90 degrees in the memory in order to efficiently access the image data in the memory. Or, it is preferable to perform a process of rotating the image by 270 degrees (vertical / horizontal conversion process).

On the other hand, a technique has been disclosed in which a vertical / horizontal conversion process is executed for each pixel block composed of a plurality of pixels included in the image data, and a vertical / horizontal conversion process is executed for each pixel to perform vertical / horizontal conversion of the image data. (See, for example, Patent Document 1).

However, in the technique of Patent Document 1, the scale of the memory may be increased due to the execution of image processing.

The subject of the disclosed technique is to execute image processing without increasing the scale of the memory.

The image processing apparatus according to one aspect of the disclosed technique includes a vertical / horizontal conversion processing unit that outputs the first image data after vertical / horizontal conversion to a storage unit, and after executing predetermined image processing on the first image data. An image processing unit that outputs the second image data of the above to the storage unit, and a rendering processing unit that outputs the third image data after executing the rendering processing to the storage unit for the second image data. To be equipped.

According to the disclosed technology, image processing can be executed without increasing the scale of the memory.

It is a block diagram which shows the whole structure example of the image formation system which concerns on embodiment. It is a figure which shows the structural example of the liquid discharge head which concerns on embodiment. It is a block diagram which shows the hardware configuration example of the liquid discharge device which concerns on embodiment. It is a figure explaining an example of a printing operation by a liquid discharge head. It is a block diagram which shows the functional structure example of the image processing apparatus which concerns on 1st Embodiment. It is a figure which shows the example of data output to the storage part by the vertical-horizontal conversion processing part which concerns on embodiment. It is a figure which shows the example of exchanging data with the storage part of the image processing part which concerns on embodiment. It is a figure which shows the example of data exchange with the storage part of the rendering processing part which concerns on embodiment. It is a flowchart which shows the processing example by the vertical-horizontal conversion processing part which concerns on embodiment. It is a flowchart which shows the processing example by the image processing part which concerns on embodiment. It is a flowchart which shows the processing example by the rendering processing part which concerns on embodiment. It is a flowchart of the processing example by the liquid discharge head which concerns on embodiment. It is a block diagram which shows the functional structure example of the image processing apparatus which concerns on 2nd Embodiment. It is a figure which shows the configuration example of a rendering data area. It is a timing chart diagram which shows the processing example for a rendering data area. It is a figure which shows the processing example for a rendering data area.

Hereinafter, modes for carrying out the invention will be described with reference to the drawings. In each drawing, the same components may be designated by the same reference numerals and duplicate description may be omitted.

In the image processing apparatus according to the embodiment, the liquid discharge head scans the liquid discharge head including the nozzle rows in which the nozzles for discharging the liquid are arranged along the transport direction of the recording medium in the direction orthogonal to the above transport direction. A liquid is discharged from the recording medium toward the recording medium to form an image on the recording medium.

Further, in the embodiment, the first image data after the vertical / horizontal conversion is output to the storage unit, and the second image data after performing predetermined image processing on the first image data is stored in the storage unit. Output. Further, by outputting the third image data after the rendering process to the above-mentioned storage unit for the second image data, the vertical / horizontal conversion process is executed without increasing the scale of the storage unit.

In the embodiment, an image forming system including a liquid discharge device (an example of an image processing device) will be described. In the figure shown below, arrows may indicate the X direction and the Y direction. The X direction indicates the main scanning direction which is orthogonal to the transport direction of the recording medium, and the Y direction indicates the recording medium. It shall indicate the sub-scanning direction which is the transport direction.

<Overall configuration of image formation system 1>
First, the overall configuration of the image forming system 1 according to the embodiment will be described with reference to FIG. FIG. 1 is a block diagram illustrating an example of the overall configuration of the image forming system 1. As shown in FIG. 1, the image forming system 1 includes a liquid discharge device 2 and a host PC (Personal Computer) 3.

The host PC 3 is a computer that outputs image data of an image to be image-formed to the liquid discharge device 2. The image to be image-formed is image data or the like read by a scanner.

The liquid discharge device 2 includes a data processing unit 21 and a liquid discharge head 22, and forms an image on a recording medium such as paper (hereinafter, simply referred to as paper) based on image data input from the host PC 3.

The data processing unit 21 executes a predetermined process on the image data input from the host PC 3, and outputs the processed image data to the liquid discharge head 22.

The liquid discharge head 22 includes a nozzle array in which nozzles for discharging the liquid are arranged along the sub-scanning direction, which is the transport direction of the recording medium, and discharges the liquid from each nozzle.

The liquid discharge device 2 scans the liquid discharge head 22 in the main scanning direction orthogonal to the paper transport direction based on the image data processed by the data processing unit 21, and while transporting the paper in the transport direction, the liquid is discharged. The liquid is discharged to the discharge head 22 to form an image on the paper.

<Structure of liquid discharge head 22>
Next, the configuration of the liquid discharge head 22 will be described with reference to FIG. FIG. 2 is a diagram illustrating an example of the configuration of the liquid discharge head 22. As shown in FIG. 2, the liquid discharge head 22 includes a cyan nozzle row 22C in which D nozzles for discharging cyan (C) color liquid are arranged in the Y direction, and a nozzle for discharging magenta (M) color liquid. A magenta nozzle row 22M in which D nozzles are arranged in the Y direction, a yellow nozzle row 22Y in which D nozzles are arranged in the Y direction to discharge a yellow (Y) color liquid, and a black (K) color liquid is discharged. A black nozzle row 22K in which D nozzles are arranged in the Y direction is provided.

The liquid discharge device 2 discharges the liquid from each nozzle of the liquid discharge head 22 while moving the liquid discharge head 22 in the X direction, thereby collectively printing with the width of the D dot shown in FIG. 2 (image). Form. The liquid discharge head 22 includes a drive unit such as a piezo element that is deformed by applying a voltage and a discharge control unit that controls the drive unit, and the drive unit is driven by the discharge control unit to discharge liquid.

<Hardware configuration of liquid discharge device 2>
Next, the hardware configuration of the liquid discharge device 2 will be described. FIG. 3 is a block diagram illustrating an example of the hardware configuration of the liquid discharge device 2.

As shown in FIG. 3, the liquid discharge device 2 includes a CPU 301 (Central Processing Unit) 301, a ROM (Read Only Memory) 302, a RAM (Random Access Memory) 303, and an NVRAM (Non-Volatile Random Access Memory) 304. The external device connection I / F (Interface) 308, the network I / F 309, and the bus line 310 are provided. The liquid discharge device 2 includes a paper transport unit 311, a sub-scanning driver 312, a main scanning driver 313, a carriage 320, an operation panel 330, and an ASIC (Application Specific Integrated Circuit). Further, the carriage 320 includes a liquid discharge head 22 and a liquid discharge head driver 321.

Of these, the CPU 301 controls the operation of the entire liquid discharge device 2. The ROM 302 stores a program or the like used to drive the CPU 301 such as an IPL (Initial Program Loader).

The RAM 303 is used as a work area of the CPU 301. The NVRAM 304 stores various data such as a program, and holds various data even while the power supply of the liquid discharge device 2 is cut off.

The external device connection I / F306 is connected to a PC by a USB (Universal Serial Bus) cable or the like, and communicates control signals and printed data with the PC. The network I / F 309 is an interface for data communication using a communication network 100 such as the Internet. The bus line 310 is an address bus, a data bus, or the like for electrically connecting each component such as the CPU 301.

The paper transport unit 311 is, for example, a roller and a motor for driving the roller, and transports the paper in the sub-scanning direction along the transport path in the liquid discharge device 2. The sub-scanning driver 312 controls the movement of the paper transport unit 311 in the sub-scanning direction. The main scanning driver 313 controls the movement of the carriage 320 in the main scanning direction.

The liquid discharge head 22 of the carriage 320 has a plurality of nozzles, and is mounted on the carriage 320 so that the discharge surface (nozzle surface) thereof faces the paper side. The liquid discharge head 22 discharges the liquid to the paper intermittently conveyed in the sub-scanning direction while moving in the main scanning direction, thereby discharging the liquid to a predetermined position on the paper to form an image. The liquid discharge head driver 321 is a driver for controlling the drive of the liquid discharge head 22.

The operation panel 330 is composed of a touch panel, an alarm lamp, or the like that displays the current set value, selection screen, or the like and accepts input from the operator.

The liquid discharge head driver 321 may not be mounted on the carriage 320, but may be configured to be connected to the bus line outside the carriage 320. Further, the main scanning driver 313, the sub scanning driver 312, and the liquid discharge head driver 321 may each have a function realized by a command of the CPU 301 according to the program.

The ASIC 340 is an electronic circuit for executing vertical / horizontal conversion processing, various image processing, rendering processing, and the like, which will be described later, on the image data input to the liquid discharge device 2.

<Image formation operation by the liquid discharge head 22>
Here, the image forming operation by the liquid discharge head 22 will be described with reference to FIG. FIG. 4 is a diagram illustrating an example of an image forming operation by the liquid discharge head 22.

In FIG. 4, the path for scanning the liquid discharge head 22 in the positive X direction from the left end to the right end of the paper P is referred to as an outward path. Further, a path for scanning the liquid discharge head 22 in the negative Y direction from the right end to the left end of the paper P is called a return path. By one scanning on the outward trip or the return trip, an image that is a part of the image data and corresponds to the entire image data in the Y direction and the X direction is formed on the paper P. For the sake of simplicity, the "image corresponding to the entire image data in the Y direction and the entire image data in the X direction" may be referred to as "an image for D dots" below.

In the image formation by the liquid discharge head 22, the liquid discharge device 2 first scans the liquid discharge head 22 in the positive X direction (outward path) while the paper P is stationary, and obtains an image for D dots as an area. It is formed on the P _11. After that, the liquid discharge head 22 is scanned to the right end of the paper P, and when the image formation in the region P ₁₁ is completed, the liquid discharge device 2 stops the liquid discharge head 22 at that position and then turns the paper P into D dots. Transport in the positive Y direction by the corresponding distance.

The liquid ejection device 2 moves the paper P by a distance corresponding to the D dot, and then stops the paper P. Then, the liquid ejection head 22 stopped at the right end of the paper P is scanned in the negative X direction (return path) to form an image for D dots in the region P ₁₂ . By repeating the scanning of the outward path and the return path and the transport of the paper, all the images corresponding to the image data can be formed on the paper P. In FIG. 4, for convenience, the liquid discharge head 22 moves from the region P ₁₁ toward the negative Y direction to form an image with the region P ₁₂ , the region P ₂₁ , ..., The region _PS2. However, in reality, the liquid discharge head 22 does not move in the Y direction, but only reciprocates in the X direction. Instead of the liquid ejection head 22 moving in the negative Y direction, the paper P is conveyed in the positive Y direction.

Further, in FIG. 4, an example in which an image is formed without overlapping the scanning ranges of the outward path and the return path is shown. However, by making the transport distance of the paper P in the Y direction smaller than the distance of D dots, the outward path and the return path The scanning range of the above may be overlapped to form an image.

Further, the range of image formation on the paper P can also be changed. For example, the image formation range in the X direction can be changed by starting from the position on the upper left side of FIG. 4 and changing the start position of image formation in the positive X direction from the origin. Similarly, the start position of image formation can be changed in the Y direction, and the image formation range in the Y direction can be changed.

Here, when the liquid discharge head 22 in which the nozzles are arranged in the Y direction is scanned in the X direction to form an image, the scanning direction of the liquid discharge head 22 (outward route, in order to efficiently access the image data on the memory). It is preferable to rotate the image data that is the source of the image formation at an angle corresponding to the return route), switch the vertical and horizontal directions of the image data, and supply the image data to the liquid discharge head 22. Such vertical / horizontal conversion processing will be described in detail separately.

[First Embodiment]
<Functional configuration of liquid discharge device 2>
Next, the functional configuration of the liquid discharge device 2 will be described with reference to FIG. FIG. 5 is a block diagram illustrating an example of the functional configuration of the liquid discharge device 2.

As shown in FIG. 5, the liquid discharge device 2 includes a vertical / horizontal conversion processing unit 211, an image processing unit 212, a rendering processing unit 213, and a storage unit 214. Of these, each function of the vertical / horizontal conversion processing unit 211, the image processing unit 212, and the rendering processing unit 213 is realized by the ASIC 340 of FIG. However, the present invention is not limited to this, and some or all of the functions in the vertical / horizontal conversion processing unit 211, the image processing unit 212, and the rendering processing unit 213 may be realized by the CPU 301, or an FPGA (field programmable gate array). ) Etc. may be realized by an electronic circuit. Further, the function of the storage unit 214 is realized by the RAM 303 or the like.

As shown in FIG. 5, the data processing unit 21 is composed of a vertical / horizontal conversion processing unit 211, an image processing unit 212, a rendering processing unit 213, and a storage unit 214. Further, the data processing unit 21 is electrically connected to the liquid discharge head 22 and the host PC 3 via the bus line 310, and can send and receive data and signals to and from each other.

Further, the storage unit 214 is provided to simultaneously execute the processes of the vertical / horizontal conversion processing unit 211, the image processing unit 212, and the rendering processing unit 213. The storage unit 214 is a vertical / horizontal conversion data area 214a and an image processing data area 214b, which are dedicated storage areas for storing data after processing by each of the vertical / horizontal conversion processing unit 211, the image processing unit 212, and the rendering processing unit 213. And the rendering data area 214c is secured.

The vertical / horizontal conversion processing unit 211, the image processing unit 212, and the rendering processing unit 213 output the image data after executing each processing to the dedicated area of the storage unit 214 and store it. The image processing unit 212 reads the image data from the vertical / horizontal conversion data area 214a and executes the image processing, and the rendering processing unit 213 reads the image data from the image processing data area 214b and executes the rendering processing. As a result, the vertical / horizontal conversion processing unit 211, the image processing unit 212, and the rendering processing unit 213 do not need to be stopped until the processing in the previous stage is completed, and the processing by each unit can be executed at the same time.

Here, the image data input from the host PC 3 to the liquid discharge device 2 is, as described with reference to FIG. 4, image data for each image data corresponding to the image formed by one scan of the liquid discharge head 22. The whole is divided and input sequentially. In the case of an image having a wide width in the scanning direction (X direction in FIG. 4) of the liquid discharge head 22, which is generally called wide, an image corresponding to the image formed by one scanning (the image for the above D dots). When divided for each data, the width of the image data in the scanning direction of the image data input to the liquid ejection device 2 is overwhelmingly wider than that in the direction orthogonal to the scanning direction (the transport direction of the paper P).

On the other hand, the image processing executed by the image processing unit 212 may include one or more processes executed using the image data of a plurality of lines. For example, when image processing is performed using an image filter having a tap size of 5 × 5 pixels, image data of 5 lines or more is required.

Therefore, the vertical / horizontal conversion processing unit 211 in FIG. 5 performs vertical / horizontal conversion of the image data in the first stage of the image processing by the image processing unit 212, and exchanges the scanning direction in the image data with the conveying direction of the paper P. In other words, the image data is rotated 90 degrees or 270 degrees. As a result, the width of the image data in the scanning direction can be suppressed to about the width corresponding to the D dots. The vertical / horizontal conversion processing unit 211 outputs the processed image data to the storage unit 214. Here, the image data processed by the vertical / horizontal conversion processing unit 211 is an example of the “first image data”.

The image processing unit 212 includes a first image processing unit 212 ₁ to an Nth image processing unit 212 _N , and uses each of them to perform N types of image processing. Further, each of the first image processing unit 212 ₁ to the Nth image processing unit 212 _N is provided with a first storage unit 212a ₁ to an Nth storage unit 212a _N in a one-to-one correspondence.

Since the width of the image data in the scanning direction is suppressed to about the width corresponding to the D dot by the processing by the vertical / horizontal conversion processing unit 211 described above, the first image processing unit 212 ₁ to the Nth image processing unit 212 _N Each of the line buffer memories for use in image processing can be configured by each of the first storage units 212a ₁ to Nth storage units 212a _N of the internal circuit, which are small-scale memories.

When the image processing unit 212 reads out the image data after the vertical / horizontal conversion processing stored in the vertical / horizontal conversion data area 214a of the storage unit 214 and executes the image processing, the first image processing unit at the head of the image processing unit 212 Before 212 ₁ starts processing, image data is read from the storage unit 214. Then, the image data is passed in a string between the first image processing unit 212 ₁ to the Nth image processing unit 212 _N , and after the final processing by the Nth image processing unit 212 _N is completed, the processed image data is stored in the storage unit 214. Output to. Here, the image data after image processing by the image processing unit 212 is an example of "second image data".

The rendering processing unit 213 reads the image data from the image processing data area 214b, executes the rendering processing for discharging the liquid by the liquid discharge head 22, and outputs the processed image data to the storage unit 214. Here, the image data processed by the rendering processing unit 213 is an example of the "third image data".

After the processing by the rendering processing unit 213 is completed, the image data stored in the storage unit 214 is transferred to the liquid discharge head 22, and image formation is performed based on the transferred image data.

<Example of data exchange with the storage unit 214 of each functional unit>
Next, an example of data exchange between the data processing unit 21 and the storage unit 214 of each functional unit will be described with reference to FIGS. 6 to 8.

FIG. 6 is a diagram illustrating an example of outputting image data to the storage unit 214 by the vertical / horizontal conversion processing unit 211.

The vertical / horizontal conversion processing unit 211 reads the image data 61 corresponding to the image formed by one scan from the memory 31 inside the host PC 3 via the bus line 310, and executes the vertical / horizontal conversion processing. Then, the processed image data 62 is output to the storage unit 214 and written.

As shown in FIG. 6, the processed image data 62 is vertically and horizontally converted with respect to the read image data 61, and apparently 90 degrees with respect to the direction 63 in which the memory addresses in the storage unit 214 are continuous. It's spinning.

Next, FIG. 7 is a diagram illustrating an example of exchanging data with the storage unit of the image processing unit 212. In FIG. 7, image data is read out for each pixel block required for image processing from the image data stored in the vertical / horizontal conversion data area 214a of the storage unit 214 after processing by the vertical / horizontal conversion processing unit 211, and the image processing unit 212 Is input to the first image processing unit 212 ₁ of. After that, after the processing from the first image processing unit 212 ₁ to the Nth image processing unit 212 _N is completed, the processed image data is output to the image processing data area 214b of the storage unit 214.

Further, in FIG. 7, image data for 7 lines is processed, and the first image processing unit 212 _{1 of the} image processing unit 212 executes image processing using an image filter having a tap size of 3 × 3 pixels. 2 The image processing unit 212 ₂ shows an example in which image processing using an image filter having a tap size of 5 × 5 pixels is executed, and other than that, image processing without using an image filter is performed. In other words, for the image data for 7 lines, the first image processing unit 212 ₁ performs image processing that refers to 3 lines, and the second image processing unit 212 ₂ performs image processing that refers to 5 lines. Other than that, image processing that refers to multiple lines is not performed.

In FIG. 7, the arrow indicated by the broken line indicates the image data for 7 lines to be processed, 71 indicates an image filter having a tap size of 3 × 3 pixels, and 72 indicates an image filter having a tap size of 5 × 5 pixels. ing.

First, image data of 7 lines to be processed and 2 lines of the maximum reference pixel are read from the vertical / horizontal conversion data area 214a, and the first image processing unit 212 ₁ uses the pixels of 8 lines for 7 lines. Image processing is performed on the pixels. In FIG. 7, the image data shown as the “first transfer” indicates the image data for 9 lines read in the first time, and the image data shown as the “second transfer” is read in the second time 9 The image data for the line is shown.

Here, the maximum reference pixel refers to a pixel for supplementing pixel data in a portion where the pixel data does not exist when performing image processing by an image filter on the end pixel in the image data. Further, the image data for 7 lines to be processed is an example of the “predetermined first pixel”. The "predetermined first pixel" may be a plurality of pixels such as image data for 7 lines, or may be one pixel. Further, the above-mentioned two-line image data of the maximum reference pixel is an example of "pixels around the first pixel". The "pixels around the first pixel" may also be a plurality of pixels such as image data for two lines, or may be one pixel.

Since the maximum reference pixel is not required for the image data read from the third time onward, image processing is performed on the pixels for 7 lines with the pixels for 7 lines. Since preferably better line buffer, each of the first image processing unit 212 1 _to N image processing unit 212 _N by the number of lines used in the image processing is provided inside, in this example a ₁ first image processing unit 212 The second image processing unit 212 ₂ preferably includes a line buffer for 9 lines, and thereafter preferably includes a line buffer for 7 lines.

Since the number of lines output to the image processing data area 214b after processing by the image processing unit 212 corresponds to the number of lines to be processed, in this example, image data for 7 lines is output. In FIG. 7, the image data shown as "first writing" is output for the first time and shows the image data for seven lines written, and the image data shown as "second writing" is the second time. The image data for 7 lines output and written in is shown.

Next, FIG. 8 is a diagram showing an example of data exchange with the storage unit 214 of the rendering processing unit 213. The rendering processing unit 213 reads image data from the image processing data area 214b of the storage unit 214, performs rendering processing, and then outputs the processed image data to the rendering data area 214c.

In the rendering data area 214c, image data processed by the vertical / horizontal conversion processing unit 211, the image processing unit 212, and the rendering processing unit 213 is accumulated, and the image data corresponding to the image for D dots is sequentially liquid. It is transferred to the discharge head 22.

<Processing by liquid discharge device 2>
Next, the processing by the liquid discharge device 2 will be described with reference to FIGS. 9 to 12. In addition, in the description, the functional configuration of FIG. 5 will be referred to as appropriate.

FIG. 9 is a flowchart illustrating an example of processing by the vertical / horizontal conversion processing unit 211.

First, in step S91, the vertical / horizontal conversion processing unit 211 acquires the parameters set in the liquid discharge head 22. This parameter is information such as the value of D in the image for D dots, for example. Based on the information in D, the number of pixels of the image data required in one scan is determined, thereby determining the number of pixels to execute the vertical / horizontal conversion process, and from the host PC 3 in one scan. The number of pixels to be read is determined.

Subsequently, in step S92, the vertical / horizontal conversion processing unit 211 determines whether or not there is a free area in the rendering data area 214c in the storage unit 214. In other words, after the processing is executed by the entire data processing unit 21, it is determined whether or not there is a vacancy in the area where the processed image data is stored.

If it is determined in step S92 that there is a free area (step S92, Yes), the process proceeds to step S93. On the other hand, if it is determined that there is no free area (step S92, No), the process of step S92 is repeated again.

Subsequently, in step S93, the vertical / horizontal conversion processing unit 211 reads out image data from the host PC 3.

Subsequently, in step S94, the vertical / horizontal conversion processing unit 211 executes the vertical / horizontal conversion processing on the image data read from the host PC 3.

Subsequently, in step S95, the vertical / horizontal conversion processing unit 211 outputs and writes the processed image data to the vertical / horizontal conversion data area 214a in the storage unit 214.

Subsequently, in step S96, the vertical / horizontal conversion processing unit 211 determines whether or not the processing has been completed for the image data of all the lines.

If it is determined in step S96 that the processing has been completed for the image data of all lines (step S96, Yes), the vertical / horizontal conversion processing unit 211 ends the processing. On the other hand, if it is determined that the processing has not been completed for the image data of all the lines (step S96, No), the process returns to step S92, and the processing after step S92 is executed again.

In this way, the vertical / horizontal conversion processing unit 211 can execute the vertical / horizontal conversion processing.

Next, FIG. 10 is a flowchart illustrating an example of processing by the image processing unit 212.

First, in step S101, the image processing unit 212 reads out image data from the vertical / horizontal conversion data area 214a in the storage unit 214.

Subsequently, in step S102, the first image processing unit 212 ₁ in the image processing unit 212 executes a predetermined image processing, and outputs the processed image data to the second image processing unit 212 ₂ .

Subsequently, in step S103, the second image processing unit 212 ₂ executes a predetermined image processing, and outputs the processed image data to the third image processing unit 212 ₃ . Then, the third image processing unit 212 ₃ predetermined processing similarly in later runs, the processed image data is output to the subsequent stage.

Subsequently, in step S104, the Nth image processing unit 212 _N in the final step in the image processing unit 212 executes a predetermined image processing.

Subsequently, in step S105, the image processing unit 212 outputs the processed image data to the image processing data area 214b in the storage unit 214 and writes it.

Subsequently, in step S106, the image processing unit 212 determines whether or not the processing has been completed for the image data of all the lines.

If it is determined in step S106 that the processing has been completed for the image data of all lines (step S106, Yes), the image processing unit 212 ends the processing. On the other hand, if it is determined that the processing has not been completed for the image data of all the lines (step S106, No), the process returns to step S101, and the processing after step S101 is executed again.

In this way, the image processing unit 212 can execute a predetermined image processing.

Next, FIG. 11 is a flowchart illustrating an example of processing by the rendering processing unit 213.

First, in step S111, the rendering processing unit 213 reads out image data from the image processing data area 214b in the storage unit 214.

Subsequently, in step S112, the rendering processing unit 213 executes the rendering process.

Subsequently, in step S113, the rendering processing unit 213 outputs the processed image data to the rendering data area 214c in the storage unit 214 and writes it.

Subsequently, in step S114, the rendering processing unit 213 determines whether or not the processing has been completed for the image data of all the lines.

If it is determined in step S114 that the processing has been completed for the image data of all lines (step S114, Yes), the rendering processing unit 213 ends the processing. On the other hand, if it is determined that the processing has not been completed for the image data of all the lines (step S114, No), the process returns to step S111, and the processing after step S111 is executed again.

In this way, the rendering processing unit 213 can execute the rendering processing.

Here, if there is no duplication of scanning, the image data written in each data area of the storage unit 214 may be read out as it is, and the ejection control may be repeated. However, if the scanning overlaps, the writing speed and the reading speed may be increased. Based on this, it is preferable to control the reading of data from the host PC 3. For example, when the scanning ranges are overlapped by half and operated, the image data to be written is the image data for two scans, while the image data to be read is the image data for three scans. In this case, since the writing speed is higher, the data reading from the host PC 3 is stopped periodically.

Next, FIG. 12 is a flowchart illustrating an example of processing by the liquid discharge head 22. More specifically, FIG. 12 illustrates processing by the discharge control unit provided in the liquid discharge head 22.

Further, when the image data that is the source of the image formed by one scan is written in the storage unit 214, the processing of FIG. 12 is performed. However, when scanning is performed in duplicate, necessary data is read from the rendering data area 214c of the storage unit 214 as the data used for ejection control.

First, in step S121, the liquid discharge head 22 sets parameters and the like.

Subsequently, in step S122, the liquid discharge head 22 determines whether or not the image data after the processing is completed is stored in the rendering data area 214c in the storage unit 214.

If it is determined in step S122 that it is stored (step S122, Yes), the process proceeds to step S123, and if it is determined that it is not stored (step S122, No), the process of step S122 is performed again. Repeated.

Subsequently, in step S123, the liquid discharge head 22 reads out image data from the rendering data area 214c in the storage unit 214.

Subsequently, in step S124, the liquid discharge head 22 executes discharge control based on the read image data.

Subsequently, in step S125, the liquid discharge head 22 determines whether or not the processing has been completed for the image data of all the lines.

If it is determined in step S125 that the processing has been completed for the image data of all lines (step S125, Yes), the liquid discharge head 22 ends the processing. On the other hand, if it is determined that the processing has not been completed for the image data of all the lines (step S125, No), the process returns to step S122, and the processing after step S122 is executed again.

In this way, the liquid discharge head 22 can discharge the liquid.

<Action and effect of liquid discharge device 2>
Conventionally, a liquid discharge device that discharges a liquid based on image data and prints it on a recording medium is known. Further, the liquid discharge device includes a liquid discharge head including a nozzle array in which nozzles for discharging liquid are arranged along the transport direction of the recording medium, and scans the liquid discharge head in the main scanning direction orthogonal to the transport direction. It is known that printing of a plurality of lines is collectively executed by making the printing.

In such a liquid discharge device, a process of rearranging the image data according to the position of the liquid discharge head is performed, and the image data is output to a memory provided in the liquid discharge device according to a continuous address in the main scanning direction from the upper left of the image. Will be done. On the other hand, as described above, the liquid discharge head collectively prints a plurality of lines in the transport direction, so that the image data is arranged 90 degrees in the memory in order to efficiently access the image data in the memory. Or, it is preferable to perform a process of rotating the image by 270 degrees (vertical / horizontal conversion process).

On the other hand, a technique has been disclosed in which a vertical / horizontal conversion process is executed for each pixel block composed of a plurality of pixels included in the image data, and a vertical / horizontal conversion process is executed for each pixel to perform vertical / horizontal conversion of the image data. There is.

However, in the above technology, a circuit such as a DMAC (Direct Memory Access Controller) or a memory for a line buffer is required for each image processing unit that executes image processing, and the scale of the circuit or memory may become large. It was.

In the present embodiment, the first image data after vertical / horizontal conversion is output to the storage unit, and the second image data after performing predetermined image processing on the first image data is output to the storage unit. Then, for the second image data, the third image data after the rendering process is executed is output to the above-mentioned storage unit.

As a result, the size of the image data to be subjected to one image processing can be reduced, and the small internal circuit provided in the image processing unit 212 and the first storage unit can be reduced without providing a large-scale line buffer externally. Image processing can be executed by the 212a ₁ to the Nth storage unit 212a _N. Further, the frequency of memory access using DMAC can be reduced, and the bus bandwidth can be reduced.

[Second Embodiment]
Next, the liquid discharge device 2a according to the second embodiment will be described.

In the present embodiment, the storage unit includes one or more write areas and two or more read areas, the write area and the read area are toggled, and the address of the pixel in the image data stored in the storage unit is set. The address of the pixel is specified so as to be continuous.

FIG. 13 is a diagram illustrating an example of the functional configuration of the liquid discharge device 2a. As shown in FIG. 13, the liquid discharge device 2a includes a data processing unit 21a. Further, the data processing unit includes a storage unit 214A, an area control unit 215, and an address designation unit 216.

The storage unit 214A includes one or more write areas and two or more read areas.

The area control unit 215 has a function of toggle between the write area and the read area in the storage unit 214A.

The address designation unit 216 has a function of designating the addresses of the pixels so that the addresses of the pixels in the image data stored in the storage unit 214A are continuous.

FIG. 14 is a diagram illustrating an example of the configuration of the rendering data area 214cA in the storage unit 214A. As shown in FIG. 14, the rendering data area 214cA included in the storage unit 214A includes an area A1, an area A2, and an area A3.

When the rendering processing unit 213 writes the processed image data, the first pixel data included in the image data is written in the area A1, the second pixel data is written in the area A2, and the third pixel data is written in the area A3. The fourth pixel data is overwritten in the area A1. If the area has four or more areas, the fifth pixel data will be overwritten. However, the area where writing is first started can be specified in any area.

If there is no duplication in scanning, the liquid discharge head 22 reads out the entire written image data as it is, so that one area A3 is used for writing and one area A1 is used for reading. If there is duplication in scanning, in addition to the latest written image data, a part of the image data written in the previous scan will also be read, so two or more areas for reading will be used. ..

The area control unit 215 toggles the area for writing the image data in each area included in the rendering data area 214cA and the area for reading the image data.

Next, FIG. 15 is a timing chart diagram showing an example of processing for the rendering data area 214cA. FIG. 15 shows the processing for the rendering data area 214cA (see FIG. 14) including the three areas.

Further, in FIG. 15, the uppermost “input image” indicates the timing at which image data is input from the host PC 3 to the liquid discharge device 2a, and the “area A1” below it is in the area A1 (see FIG. 14). It indicates the timing at which the image data is written and read. Further, "Area A2" below it indicates the timing at which image data is written and read out in Area A2 (see FIG. 14), and "Area A3" below it indicates an image in Area A3 (see FIG. 14). Indicates the timing at which data is written and read. The "output image" at the bottom shows the timing at which the image data is output to the liquid discharge head 22.

When there is overlap in scanning, as shown in FIG. 15, there is a deviation in line units between the input timing of the image data from the host PC 3 and the output timing of the image data to the liquid discharge head 22. Occur. For example, when the overlap of scanning is less than half the width of the scanning range, as shown in FIG. 15, a delay of one transfer unit of image data always occurs. On the other hand, when the scanning overlap is more than half the width of the scanning range, the image data writing is faster than the image data reading.

Next, FIG. 16 is a diagram illustrating an example of processing for the rendering data area 214cA. Areas A1 to A3 are shown in FIG. 16 as in FIG. In addition, each of the grids shown inside each of the areas A1 to A3 indicates pixel data in the image data. Further, the numerical values shown in some of the grids indicate the memory addresses in the rendering data area 214cA.

When writing the pixel data in the image data after the rendering process to the rendering data area 214cA, the address designation unit 216 causes the memory address to be written so as to be continuous with the previous processing block. In the example of FIG. 16, writing of three processing blocks from addresses 0 to 11 is completed, and when writing a fourth processing block, one processing block is written from address 12. The D (scanning width) of the image for D dots formed by one scanning by the liquid discharge head 22 is 4 pixels.

By the function of the addressing unit 216, the addresses of 4 pixels corresponding to the scanning width by the leading liquid discharge head 22 are always continuous with respect to the previous processing block regardless of the writing to any area. become. As a result, even when the pixels of a plurality of processing blocks are used, the pixels can be continuously transferred.

[Action and effect of liquid discharge device 2a]
In the present embodiment, the storage unit 214 includes one or more writing areas and two or more reading areas, and the writing area and the reading area are toggled to obtain pixels in the image data stored in the storage unit 214. The address of the pixel is specified so that the addresses are continuous. This enables burst transfer across a plurality of areas regardless of the area where the start address is located.

Although the embodiments have been described above, the present invention is not limited to the above-described embodiments specifically disclosed, and various modifications and changes can be made without departing from the scope of claims. is there.

The embodiment also includes an image processing method. For example, the image processing method includes a step of outputting the first image data after vertical / horizontal conversion to the storage unit and the storage of the second image data after performing predetermined image processing on the first image data. It includes a step of outputting to the unit and a step of outputting the third image data after executing the rendering process to the storage unit for the second image data. By such an image processing method, the same effect as that of the above-mentioned image processing device (liquid ejection device) can be obtained.

In addition, embodiments also include programs. For example, the program outputs the first image data after the vertical / horizontal conversion to the storage unit, and outputs the second image data after executing a predetermined image process on the first image data to the storage unit. The computer is made to execute a process of outputting the third image data after executing the rendering process to the storage unit for the second image data. With such a program, the same effect as that of the image processing apparatus described above can be obtained.

Further, each function of the embodiment described above can be realized by one or a plurality of processing circuits. Here, the "processing circuit" in the present specification is a processor programmed to execute each function by software such as a processor implemented by an electronic circuit, or a processor designed to execute each function described above. It shall include devices such as ASIC (Application Specific Integrated Circuit), DSP (digital signal processor), FPGA (field programmable gate array) and conventional circuit modules.

1 Image formation system 2 Liquid discharge device 21 Data processing unit 211 Vertical / horizontal conversion processing unit 212 Image processing unit 213 Rendering processing unit 214 Storage unit 214a Vertical / horizontal conversion data area 214b Image processing data area 214c Rendering data area 215 Area control unit 216 Address designation unit P paper

JP-A-2019-022071

Claims (5)

A vertical / horizontal conversion processing unit that outputs the first image data after vertical / horizontal conversion to the storage unit,
An image processing unit that outputs the second image data after performing predetermined image processing on the first image data to the storage unit, and an image processing unit.
An image processing device including a rendering processing unit that outputs the third image data after executing the rendering processing to the storage unit with respect to the second image data. The second image data is
The first pixel after executing the predetermined image processing on a predetermined first pixel in the first image data or a pixel block composed of the first pixel and pixels around the first pixel. The image processing apparatus according to claim 1, which includes pixel data of one pixel. The storage unit including one or more write areas and two or more read areas,
An area control unit that toggles the writing area and the reading area,
The image processing apparatus according to claim 1 or 2, further comprising an address designation unit for designating the address of the pixel so that the address of the pixel in the image data stored in the storage unit is continuous. The process of outputting the first image data after vertical / horizontal conversion to the storage unit, and
A step of outputting the second image data after executing a predetermined image process on the first image data to the storage unit, and
An image processing method including a step of outputting a third image data after executing a rendering process to the storage unit with respect to the second image data. Output the first image data after vertical / horizontal conversion to the storage unit,
The second image data after executing the predetermined image processing on the first image data is output to the storage unit.
A program that causes a computer to execute a process of outputting the third image data after executing a rendering process to the storage unit for the second image data.

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