JP6540458B2 - Image processing method, image processing apparatus, and printing system - Google Patents

Description

  The present invention relates to an image processing method that generates print data that causes a printing apparatus to execute printing based on image data, an image processing apparatus that generates print data by the image processing method, and a printing system that includes the image processing apparatus.

  Inkjet printers as printing apparatuses have undergone innovation in printing technology along with image processing technology, and various forms of printing have become possible using various presentation means on various print media. As a result, for example, it is widely used for medium-sized printers for commercial applications corresponding to the creation of posters, billboards, promotional materials, wrapping paper, clothing, etc., large-sized printers for industrial applications to be incorporated into product production lines, etc. Became. Along with this, the size of image data for performing large format and high definition printing has become larger and the time required for image processing for generating print data for driving a printer has become longer. On the other hand, speeding up of processing is achieved by using a general purpose DSP (Digital Signal Processor) as an image processing engine.

  When a general purpose DSP is used for the printing system, the endianness of the main CPU and the endianness of the DSP may differ, and in that case, it is necessary to newly provide a means for absorbing the endian difference. For example, Patent Document 1 describes an inter-CPU data communication system that can reduce the work load when there are CPUs with different endians in the system. This inter-CPU data communication system sets either big endian or little endian as unity endian of the whole system, and in the communication program executed by the CPU when its own endian differs from unity endian, A processing part that rearranges data so as to be uniform endian regardless of the endian of the communication partner, and performs processing on the transmitting side to perform rearrangement processing, and a receiving side that rearranges the received data into its own endian and stores it in memory Are configured to have at least one of a processing portion that performs the rearrangement process of

JP, 2005-227998, A

  However, in the inter-CPU data communication system described in Patent Document 1, the time required for the rearrangement process performed on either the transmission side or the reception side may be long, and the main CPU and DSP in the printing system When the means for sorting is used as means for absorbing the endian difference between the two, there is a problem that the printing efficiency may be lowered.

  The present invention has been made to solve the above-described problems, and can be realized as the following application examples or embodiments.

  Application Example 1 An image processing method according to this application example is an image processing method for generating print data that causes a printing apparatus to execute printing of a desired image based on image data, and a predetermined image processing method is used based on the image data. The data processing result is written for each data processing unit based on a data processing step of performing data processing for each long data unit and a write data table in which write data are arranged according to the data processing result of the data processing step. And a data writing process to be performed, wherein the write data table is configured based on an endian of the data processing process and an endian of an image processing system to which the data processing result is written. Do.

  According to this application example, the write data table in which the write data according to the data processing result is arranged is configured based on the endian of the data processing process and the endian of the image processing system of the write destination to write the data processing result. Since the data processing result is written, it is possible to complete the writing with appropriate endianness. For this reason, it is not necessary to perform processing to rearrange the data processing result whose data processing has been completed again in accordance with the endian of the image processing system of the write destination, and as a result, print data can be generated at higher speed.

  Application Example 2 In the image processing method according to the application example, the write data table corresponds to the case where the endian of the data processing step and the endian of the image processing system of the write destination to which the data processing result is written are the same. The first data writing step includes the first writing data table, and the second writing data table corresponding to the case where the endian of the data processing step is different from the endian of the image processing system to which the data processing result is written. Selecting either the first write data table or the second write data table in correspondence with the endianness of the data processing process and the endianness of the image processing system to which the data is written. It is characterized by

  According to this application example, since the appropriate write data table is selected in correspondence with the endian of the data processing process and the endian of the image processing system to which the data processing result is written, the image processing for generating print data In the case where a system includes a plurality of image processing systems with different endianness, or when a part of the image processing system is replaced with an image processing system with different endianness, etc., it is possible to cope more flexibly.

  Application Example 3 In the image processing method according to the application example described above, the data processing step generates halftone data including data of presence / absence and / or size of dots constituting the desired image. It is characterized by being.

  According to this application example, since the processing result of the halftone processing step can be written in correspondence with the endian of the subsequent image processing step, the endian in the halftone processing step and the result of the halftone processing are processed thereafter Even if the endian of the image processing step is different, it is not necessary to perform processing to rearrange the data for which halftoning has been completed according to the endian of the image processing system of the write destination again. As a result, printing is performed faster It is possible to generate data.

  Application Example 4 An image processing apparatus according to this application example is an image processing apparatus that generates print data that causes a printing apparatus to execute printing of a desired image based on image data, and a predetermined value is generated based on the image data. Writing of the data processing result for each data processing unit based on a data processing unit that performs data processing for each long data unit and a write data table in which write data according to the data processing result of the data processing unit are arranged A write data table for performing the write data table based on the endianness of the data processing unit and the endianity of the image processing system to which the data processing result is written. Do.

  According to this application example, the write data table in which the write data according to the data processing result is arranged is configured based on the endian of the data processing unit and the endian of the image processing system to which the data processing result is written. Since the data processing result is written, it is possible to complete the writing with appropriate endianness. For this reason, it is not necessary to perform processing to rearrange the data processing result whose data processing has been completed again in accordance with the endian of the image processing system of the write destination, and as a result, print data can be generated at higher speed.

  Application Example 5 In the image processing apparatus according to the application example, the writing data table corresponds to the case where the endianness of the data processing unit and the endianness of the writing destination image processing system for writing the data processing result are the same. (1) a write data table, and a second write data table corresponding to the case where the endian of the data processing unit and the endian of the image processing system to which the data processing result is written are different; One of the first write data table and the second write data table may be selected according to the endianness of the data processing unit and the endianness of the image processing system to which the data is to be written.

  According to this application example, since the appropriate writing data table is selected in correspondence with the endianness of the data processing unit and the endianness of the image processing system to which the data processing result is to be written, the print data in the image processing apparatus In the case where a plurality of image processing systems with different endianness are included in the image processing system that generates the image data, or when a part of the image processing system is replaced with an image processing system with different endianness, etc., more flexibility can be achieved.

  Application Example 6 A printing system according to this application example includes the printing apparatus and the image processing apparatus described in the application example.

  According to this application example, the image processing apparatus that generates print data that causes the printing apparatus to execute printing of a desired image based on image data can generate print data at a higher speed, so it is possible to perform more efficiently. It can print.

Front view showing the configuration of the printing system according to the first embodiment Block diagram showing the configuration of the printing system according to the first embodiment Illustration of basic functions of printer driver Conceptual diagram showing an example of arrangement of pixel data as a result of halftone processing Conceptual diagram in which the data to be written is arranged on the time axis in byte units A conceptual diagram showing an example in which the arrangement of pixel data as a result of halftone processing is erroneously recognized Conceptual diagram showing an example of the first write data table Conceptual diagram showing an example of the second write data table A flowchart showing a flow of print data generation processing in the first embodiment A flowchart showing a flow of print data generation processing in the second embodiment

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following is one embodiment of the present invention, and not intended to limit the present invention. In addition, in each following figure, in order to make an explanation intelligible, it may be described in the scale different from actual. In addition, in the coordinates appended to the drawing, the Z-axis direction is vertical, + Z direction is upward, Y-axis direction is front-back, + Y direction is nearer, X-axis direction is horizontal, + X direction is left, X The -Y plane is a horizontal plane.

(Embodiment 1)
<Printing system>
FIG. 1 is a front view showing the configuration of the printing system 1 according to the first embodiment, and FIG. 2 is a block diagram of the same.
The printing system 1 includes a printing apparatus 100 and a personal computer 110 (hereinafter referred to as a PC 110) as an “image processing apparatus” connected to the printing apparatus 100. The printing apparatus 100 is an inkjet printer that prints a desired image on a long print medium 5 supplied in a rolled state based on print data received from the PC 110.

<Basic Configuration of Image Processing Device (PC 110)>
The PC 110 includes a printer control unit 111, an input unit 112, a display unit 113, a storage unit 114, and the like, and controls a print job that causes the printing apparatus 100 to print.
The software that the PC 110 operates includes general image processing application software (hereinafter referred to as application) that handles image data to be printed, control of the printing apparatus 100, and print data for causing the printing apparatus 100 to execute printing. Printer driver software (hereinafter referred to as a printer driver) is included.

The printer control unit 111 includes a central processing unit (CPU) 115, an application specific integrated circuit (ASIC) 116, a digital signal processor (DSP) 117, a memory 118, a printer interface unit 119, etc. I do.
The input unit 112 is an information input unit as a human interface. Specifically, for example, a keyboard or a port to which an information input device is connected.
The display unit 113 is an information display unit (display) as a human interface, and relates to information input from the input unit 112, an image to be printed on the printing apparatus 100, and a print job under the control of the printer control unit 111. Information etc. are displayed.
The storage unit 114 is a rewritable storage medium such as a hard disk drive (HDD) or a memory card, and the software (a program operated by the printer control unit 111) in which the PC 110 operates, an image to be printed, and information related to a print job Etc. are stored.
The memory 118 is a storage medium for securing an area for storing a program in which the CPU 115 operates, a working area for operation, and the like, and is configured by a storage element such as a RAM or an EEPROM. Further, in the memory 118, a “data processing result” to be described later is stored by the DSP 117.

<Basic Configuration of Printing Device 100>
The printing apparatus 100 includes a printing unit 10, a print medium moving unit 20, a control unit 30, and the like. The printing apparatus 100 having received the print data from the PC 110 controls the printing unit 10 and the printing medium moving unit 20 by the control unit 30 to print an image on the printing medium 5 (image formation).
The print data is, for example, an image formed by converting general image data (for example, digital image information of RGB) obtained by a digital camera or the like into a printing apparatus 100 so as to be printed by an application and a printer driver included in the PC 110 And includes commands for controlling the printing apparatus 100.

The printing unit 10 includes a print head 11, a print head control unit 12, and the like.
The print medium moving unit 20 includes a main scanning unit 40, a sub scanning unit 50, and the like. The main scanning unit 40 includes a carriage 41, a guide shaft 42, a carriage motor (not shown), and the like. The sub-scanning unit 50 includes a supply unit 51, a storage unit 52, a conveyance roller 53, a platen 55, and the like.

  The print head 11 has a plurality of nozzles (nozzle rows) for discharging printing ink (hereinafter referred to as ink) as droplets (hereinafter also referred to as ink droplets). The print head 11 is mounted on the carriage 41, and reciprocates in the scanning direction along with the carriage 41 moving in the scanning direction (Y-axis direction shown in FIG. 1). By discharging ink droplets onto the print medium 5 supported by the platen 55 under the control of the control unit 30 while moving the print head 11 in the scan direction, the dot rows (raster lines) along the scan direction The print medium 5 is formed.

  The ink includes, for example, a four-color ink set obtained by adding black (K) to a three-color ink set of cyan (C), magenta (M), and yellow (Y) as an ink set consisting of a dark ink composition There is. Also, for example, eight colors added with an ink set such as light cyan (Lc), light magenta (Lm), light yellow (Ly), light black (Lk), and the like which are light ink compositions in which the concentration of each color material is lightened There is ink set of.

As a system (ink jet system) for discharging ink droplets, a piezo system is used as a preferred example. The piezo method is a method in which a pressure corresponding to a print information signal is applied to ink stored in a pressure chamber by a piezoelectric element (piezo element), and ink droplets are ejected (discharged) from a nozzle communicating with the pressure chamber for printing.
Note that the method of ejecting the ink droplet is not limited to this, and another recording method may be used in which the ink is ejected in the form of droplets and a dot group is formed on the printing medium. For example, pressure is applied to the ink with a small pump, and the nozzle is forcibly vibrated by a quartz oscillator or the like to forcibly eject the ink droplet, the ink is heated and foamed by the micro electrode according to the recording information signal, It may be a system (thermal jet system) or the like in which a droplet is ejected and recorded.

The printing medium moving unit 20 (main scanning unit 40, sub scanning unit 50) moves the printing medium 5 relative to the printing unit 10 under the control of the control unit 30.
The guide shaft 42 extends in the scanning direction and supports the carriage 41 in a slidable manner, and the carriage motor serves as a drive source for reciprocating the carriage 41 along the guide shaft 42. That is, the main scanning unit 40 (carriage 41, guide shaft 42, carriage motor) moves the carriage 41 (that is, the print head 11) in the scanning direction along the guide shaft 42 under the control of the control unit 30. .

The supply unit 51 rotatably supports a reel on which the print medium 5 is wound in a roll, and feeds the print medium 5 to the transport path. The storage unit 52 rotatably supports a reel for taking up the print medium 5 and takes up the print medium 5 for which printing has been completed from the transport path.
The transport roller 53 includes a drive roller for moving the print medium 5 in the sub scanning direction (X-axis direction shown in FIG. 1) intersecting the scanning direction, a driven roller which rotates with the movement of the print medium 5, etc. A conveyance path is configured to be conveyed from the supply unit 51 to the storage unit 52 via the printing area of the printing unit 10 (the area on the upper surface of the platen 55 where the print head 11 scans and moves).

The control unit 30 includes an interface unit 31, a CPU 32, a memory 33, a drive control unit 34, a drive data setting unit 35, and the like, and controls the printing apparatus 100.
The interface unit 31 is connected to the printer interface unit 119, and transmits and receives data between the PC 110 and the printing apparatus 100.
The CPU 32 is an arithmetic processing unit for controlling the entire printing apparatus 100.
The memory 33 is a storage medium for securing an area for storing a program in which the CPU 32 operates, a working area for the operation, and the like, and is configured by a storage element such as a RAM or an EEPROM.
The CPU 32 controls the print medium moving unit 20 (main scanning unit 40, sub scanning unit 50), the printing unit 10 (printing) according to the program stored in the memory 33 and the print data received from the PC 110 via the drive control unit 34. While controlling the head 11), the head drive data to be described later is sequentially sent out to the print head control unit 12 through the drive data setting unit 35.

  With the above-described configuration, the control unit 30 supports the print head 5 along the guide shaft 42 with respect to the print medium 5 supplied to the printing area by the sub-scanning unit 50 (the supply unit 51 and the conveyance roller 53). To move the print medium 5 in the conveyance direction (+ X direction) intersecting the scanning direction by the sub scanning unit 50 (conveying roller 53) that discharges ink droplets from the print head 11 while moving the scanning direction (Y axis direction) A desired image is formed (printed) on the print medium 5 by alternately repeating the operation to be performed.

<Basic function of printer driver>
FIG. 3 is an explanatory diagram of a basic function of the printer driver.
Printing on the print medium 5 is started by sending print data from the PC 110 to the printing apparatus 100. Print data is generated by a printer driver.
Hereinafter, the print data generation process will be described with reference to FIG.

  The printer driver receives image data (for example, text data or full-color image data) from an application, converts it into print data in a format that can be interpreted by the printing apparatus 100, and outputs the print data to the printing apparatus 100. When converting image data from an application into print data, the printer driver performs resolution conversion processing, color conversion processing, halftone processing, rasterization processing, command addition processing, and the like.

The resolution conversion process is a process of converting image data output from an application into a resolution (print resolution) when printing on the print medium 5. For example, when the print resolution is specified as 720 × 720 dpi, the vector format image data received from the application is converted to bitmap data of 720 × 720 dpi resolution. Each pixel data of the image data after resolution conversion processing is composed of pixels arranged in a matrix. Each pixel has a gradation value of, for example, 256 gradations in the RGB color space. That is, the pixel data after resolution conversion indicates the gradation value of the corresponding pixel.
Pixel data corresponding to one row of pixels arranged in a predetermined direction among the pixels arranged in a matrix is referred to as raster data. The predetermined direction in which the pixels corresponding to raster data are arranged corresponds to the moving direction (scanning direction) of the print head 11 when printing an image.

The color conversion process is a process of converting RGB data into data of a CMYK color system space. The CMYK colors are cyan (C), magenta (M), yellow (Y), and black (K), and the image data of the CMYK color system space is data corresponding to the color of the ink that the printing apparatus 100 has. . Therefore, for example, when the printing apparatus 100 uses 10 types of ink of the CMYK color system, the printer driver generates image data of a 10-dimensional space of the CMYK color system based on RGB data.
This color conversion process is performed based on a table (color conversion lookup table LUT) in which the gradation values of RGB data are associated with the gradation values of CMYK color system data. The pixel data after the color conversion process is CMYK color system data of, for example, 256 gradations represented by the CMYK color system space.

The halftone process is a process of converting data of high gradation number (256 gradations) into data of gradation number that the printing apparatus 100 can form. By this halftoning process, the data showing 256 gradations is 1 bit data showing 2 gradations (with and without dots) and 2 bits showing 4 gradations (without dots, small dots, medium dots and large dots) Converted to data. Specifically, from the dot generation rate table in which the gradation value (0 to 255) and the dot generation rate correspond to each other, the generation rate of dots corresponding to the gradation value (for example, in the case of 4 gradations, no dot, small The generation rates of dots, medium dots, and large dots are determined, and at the obtained generation rates, pixel data is created so that dots are formed in a dispersed manner using dithering, error diffusion, etc. Ru.
That is, pixel data after halftone processing is 1-bit or 2-bit data, and this pixel data is data indicating dot formation (presence or absence of dots, dot size) in each pixel. For example, in the case of 2 bits (4 tones), a dot tone value [00] corresponding to no dot, a dot tone value [01] corresponding to the formation of small dots, a dot tone corresponding to the formation of medium dots The value is converted into four stages as [10] and dot gradation value [11] corresponding to formation of a large dot.
In the present embodiment, the halftone processing step corresponds to the “data processing step” in which data processing is performed for each data unit of a predetermined length.

FIG. 4 shows an example of the arrangement of pixel data as a result of halftone processing. The example shown in the drawing shows the result of expanding image data of high gradation number (256 gradations) into 2-bit data of 4 × 4 matrix by halftone processing. This corresponds to one ink, and is developed into such 2-bit data for each ink color.
Each of d1 to d16 arranged in a 4 × 4 matrix is 2-bit data corresponding to the dot formation position, and any of [00], [01], [10], and [11] obtained by halftone processing. Contains some data.
The following description will be made in the case where pixel data after halftone processing is 2 bits (4 gradations: no dot, small dot, medium dot, large dot).

The rasterization process is a process of rearranging pixel data (2-bit data) arranged in a matrix in accordance with the dot formation order at the time of printing.
The command addition process is a process of adding command data according to the printing method to the rasterized data. The command data includes, for example, transport data related to the transport specification of the medium (the amount of movement in the sub scanning direction, the speed, and the like).
The processing by the printer driver is performed by the ASIC 116 and the DSP 117 (see FIG. 2) under the control of the CPU 115, and the generated print data is transmitted to the printing apparatus 100 via the printer interface unit 119.

In the print data generation process (image process) described above, the size of the image to be printed is increased, the number of ink used is increased, and as the quality (resolution) is increased, the number of pixels to be processed is increased. The time required for As a result, since printing can not be started until print data is generated, depending on the image processing time, printing efficiency may be significantly reduced.
Therefore, in the present embodiment, in the print data generation process, the halftone process with the largest processing load is executed by the DSP 117 capable of performing calculations at higher speed. As the DSP 117, it is possible to use a general-purpose DSP, and when the image processing load is further increased, it is also possible to use a plurality of DSPs 117 for parallel processing.

However, when a general purpose DSP is used as the DSP 117, the endianness of the ASIC 116 and the endianness of the DSP 117 may be different. If the difference in endianness affects the processing result, it can be dealt with by converting the processing result according to the endian, but it takes time for this conversion processing to generate print data, that is, print The efficiency of the
In the print data generation process, image data of high gradation number (256 gradations) is expanded into 2 bits data (2 bits × 16 = 32 bits = 4 bytes) of 4 × 4 matrix by halftone processing. Therefore, if the order of processing in units of bytes changes, processing results will be affected. That is, at least before and after halftoning, processing for absorbing the difference in endianness is required. Therefore, in the present embodiment, in the writing process of the result of performing the halftone process for each pixel, the writing of the process result is performed for each data processing unit based on the write data table in which the write data according to the process result is arranged. In this case, the write data table is configured based on the endianness of the ASIC 116 and the endianness of the DSP 117 so that it is not necessary to perform subsequent conversion processing.
In the present embodiment, the process of performing the writing process as a result of the halftone process corresponds to the “data writing process”.
The details will be described below.

  First, the influence of the endian difference in the delivery of halftone processing results will be described. The delivery of the halftone processing result means the delivery of the result of the halftone processing by the DSP 117 to the subsequent rasterization processing by the ASIC 116, and more specifically, the processing for writing the memory 118.

  The DSP 117 completes the halftoning process corresponding to the high gradation number (256 gradations) image data, and outputs a set (d1 to d16) of 2-bit data constituting a 4 × 4 matrix shown in FIG. A 4 × 4 matrix set of 2-bit data is 2 bits × 16 = 32 bits = 4 bytes of data. For example, when the DSP 117 writes data to the memory 118 by the big endian recording method, FIG. As shown, write from the upper byte. FIG. 5 is a diagram in which data to be written is arranged on a time axis in byte units. Since the memory 118 is recorded by the big endian recording method, data of 32 bits = 4 bytes is recorded as a data string as it is shown in FIG.

On the other hand, for example, when the rasterization process by the ASIC 116 is performed by the little endian recording method, a 4 × 4 matrix set of 2-bit data is recognized as data written from the lower byte, When configured in a 4 × 4 matrix, the ASIC 116 erroneously recognizes the matrix as the array shown in FIG.
Therefore, in the present embodiment, in order to prevent this erroneous recognition, the DSP 117 performs writing in accordance with the endianness of the ASIC 116 which is the endianness of the image processing system of the writing destination.

Specifically, the following processing is performed for writing the halftone processing result.
First, a method in the case where the endian of the image processing system to which data is to be written is the same will be described.
In the writing of the halftone processing result, the writing of the processing result is performed for each data processing unit based on the write data table in which the write data according to the halftone processing result is arranged.

  FIG. 7 corresponds to the case where the endian of the halftone processing step as the “data processing step” and the endian of the image processing system (the endian of the ASIC 116) of the write destination to write the data processing result (halftone processing result) are the same. It is an example of a write data table (first write data table). This data table (hereinafter referred to as the first write data table) is a 32-bit = 4-byte data string (shown in FIG. 5) as a data string corresponding to the 4 × 4 matrix set of 2-bit data shown in FIG. It is a data table for generating a data string of unit length. Blocks in the upper, middle, lower, and lower four rows in FIG. 7 correspond to small dots, medium dots, and large dots, respectively, and 1 to 4 rows of each block and columns A to D are 4 × 4 in FIG. It corresponds to the matrix position. Also, the numerical values shown in the box are in hexadecimal notation.

  In the step of writing the halftone processing result, using the numerical values of the first write data table, a 32-bit = 4-byte data string to be written is generated. Specifically, the position in the matrix of the 4 × 4 matrix obtained by the halftone processing and the data at the position corresponding to the value of 2-bit data (4 gradations) at that position (corresponding bit is 1 A data string of 32 bits = 4 bytes to be written is generated by selecting data) and adding all the selected 16 data.

  For example, as a result of halftone processing, d1 to d4 are [01], [10], [11], and [00] (that is, small dots, medium dots, large dots, no dots), and d5 to d16 are [00] ( That is, the case where it is converted to "no dot" will be described. From the first write data table (FIG. 7), first, data (40000000) at the position (small 1 row A column) corresponding to d1 = small dot is selected. Similarly, data (20000000) at the position (middle 1 row B column) corresponding to d2 = medium dot is selected, and data (0C000000) at the position (large one row C column) corresponding to d3 = large dot is selected. Ru. Data (00000000) is selected for d4 to d16 because there is no dot. If these data are added, it will be 6C000000. In binary notation, the portion 6C is 00110 1100, and the sequence of bits is placed at the position of the most significant byte of the sequence of d1 to d4 [01], [10], [11], [00]. It becomes a data string.

  FIG. 8 shows a write data table corresponding to the case where the endian of the halftone processing step as the “data processing step” is different from the endian of the image processing system of the write destination to which the data processing result (halftone processing result) is written. 2) an example of the write data table). By performing the same processing as described above using this data table (hereinafter referred to as the second write data table), a 32-bit = 4-byte data string to be written according to different endianness is generated.

  For example, the case where d1 to d4 are converted to [01], [10], [11], [00], and d5 to d16 as [00] as a result of the halftone processing as described above will be described. From the second write data table (FIG. 8), first, data (00000040) at a position (small 1 row A column) corresponding to d1 = small dot is selected. Similarly, data (00000020) at the position (middle 1 row B column) corresponding to d2 = medium dot is selected, and data (0000000C) at the position (large one row C column) corresponding to d3 = large dot is selected. Ru. Data (00000000) is selected because d4 to d16 = no dot. When these data are added, it becomes 0000006C. In binary notation, the portion 6C is 001101100, and the sequence of bits is placed at the position of the least significant byte of the sequence [01], [10], [11], [00] of d1 to d4. It becomes a data string.

  As described above, the write data table in which the write data according to the halftoning result is arranged is configured in consideration of the endian of the halftoning process and the endian of the image processing system of the writing destination. It is possible to perform appropriate writing in accordance with endianness without performing conversion processing. Embodiments of several image processing devices (PCs 110) that utilize this method will now be described.

Example 1
The image processing apparatus according to the first embodiment has a configuration in which one DSP 117 having a different endian from the ASIC 116 is used in the PC 110 shown in FIG.
In the print data generation processing, resolution conversion processing and color conversion processing are performed by the ASIC 116, and the subsequent halftone processing is performed by the DSP 117. Also, the DSP 117 writes the halftone processing result to the memory 118, and the ASIC 116 performs subsequent rasterization processing and the like. The storage unit 114 stores a second write data table in advance.

FIG. 9 is a flowchart showing a flow of print data generation processing as the “image processing method” in the first embodiment.
In the configuration of the first embodiment, the “data processing unit” that performs data processing for each data unit of a predetermined length based on image data is configured as the functional unit 120 of the DSP 117 that performs halftone processing. Further, the "data writing unit" which performs writing of the data processing result for each data processing unit based on the write data table in which the write data according to the data processing result of the data processing unit is arranged corresponds to the halftone processing result. The functional unit 121 of the DSP 117 performs writing of the halftone processing result for each data processing unit based on the second write data table in which the write data is arranged.

The printer driver receives image data from the application, and performs resolution conversion processing and color conversion processing in the ASIC 116 (steps S1 and S2).
Next, the DSP 117 receives the color conversion processing result in the functional unit 120 and performs halftone processing (step S3).
Next, the DSP 117 causes the functional unit 121 to generate write data (a data string of a unit length shown in FIG. 5) with reference to the second write data table (step S4), and writes it as a halftone processing result to the memory 118. (Step S5).

  Next, the ASIC 116 reads the halftone processing result from the memory 118, performs subsequent rasterization processing and command addition processing, and completes the print data (steps S6 and S7).

(Example 2)
The image processing apparatus according to the second embodiment has a configuration in which a plurality of DSPs 117 including a DSP 117 having a different endian from the ASIC 116 are used in the PC 110 shown in FIG. That is, this is an example in the case where DSPs 117 with different endianness are mixed.
In the print data generation processing, resolution conversion processing and color conversion processing are performed by the ASIC 116, and the halftone processing thereafter is shared and executed by the plurality of DSPs 117. Further, each of the plurality of DSPs 117 writes the halftone processing result to the memory 118, and the ASIC 116 performs the subsequent rasterization processing and the like. The storage unit 114 stores a first write data table and a second write data table in advance.

  FIG. 10 is a flowchart showing a flow of print data generation processing as the “image processing method” in the second embodiment. FIG. 10 shows a flow in the case of using two DSPs 117 a and 117 b as the plurality of DSPs 117. The DSP 117a has the same endian as the ASIC 116, and the DSP 117b has the same endian as the ASIC 116. The number of DSPs 117 is not limited to two. For example, the number of DSPs 117 corresponding to the number of ink may be mounted, and halftone processing may be shared for each type of ink.

The printer driver receives image data from the application, and performs resolution conversion processing and color conversion processing in the ASIC 116 (steps S1 and S2).
Next, the DSP 117a and the DSP 117b receive the color conversion processing result and perform halftone processing of their respective divisions in the respective functional units 120 (step S3).

Next, the DSP 117a and the DSP 117b recognize the endianness of each of the functional units 121 (step S4), and select the write data table corresponding to the recognized endianness (step S5). Specifically, the DSP 117a selects the first write data table corresponding to the same endian, and the DSP 117b selects the second write data table corresponding to the different endian. Next, write data (data string of unit length shown in FIG. 5) is generated with reference to the write data table selected by each (step S6), and the memory 118 is written as a halftone processing result (step S7).
The endian recognition in step S4 and the selection of the write data table in step S5 may be performed only at the first time, and the generation of write data from the second time (step S6) refers to the same write data table selected at the first time. You should do it.

  Next, the ASIC 116 reads the halftone processing result from the memory 118, performs subsequent rasterization processing and command addition processing, and completes the print data (steps S8 and S9).

As described above, according to the image processing method, the image processing apparatus, and the printing system according to the present embodiment, the following effects can be obtained.
A write data table (a first write data table and a second write data table) in which write data according to the halftoning result are arranged is a writing destination to which the endian of the halftoning process (DSP 117) and the halftoning result are written Since the image processing system (ASIC 116) is configured on the basis of the endianness of the image processing system (ASIC 116), the writing with the appropriate endianness can be completed each time the halftone processing result is written. Therefore, there is no need to perform processing to rearrange the processing result for which halftone processing has been completed according to the endian of the image processing system (ASIC 116) of the write destination, and as a result, print data can be generated faster. it can.

  Further, in the second embodiment, an appropriate write data table is selected in correspondence with the endian of the halftone processing step (DSP 117) and the endian of the image processing system (ASIC 116) of the write destination to which the halftone processing result is written. Therefore, in the case where an image processing system that generates print data includes a plurality of image processing systems with different endianness, or when a part of the image processing system is replaced with an image processing system with different endianness, etc. be able to.

  In addition, the printing system 1 includes the printing apparatus 100 and the image processing apparatus (PC 110), so that the image processing apparatus (PC 110) generates print data that causes the printing apparatus 100 to print a desired image based on image data. Since the print data can be generated at higher speed, printing can be performed more efficiently.

In the second embodiment described above, the configuration in the case of using a plurality of DSPs 117 including DSPs 117 different in endianness from the ASIC 116 has been described. However, the type and number of DSPs 117 mounted in advance are used as the configuration of the image processing apparatus (PC 110). Both the case where it is fixed and configured as an image processing apparatus and completed, and the case where a necessary number of DSPs 117 are added and configured as needed when printing can be considered.
In the case where the type and number of the DSP 117 mounted in advance are fixed, it is sufficient to recognize the endian structure as the image processing apparatus and set the corresponding write data table when the image processing apparatus is configured. . In addition, when a necessary number of DSPs 117 are added and configured as needed when printing is performed, the configuration of the endian is recognized every time the configuration of the image processing apparatus is changed, for example, the DSP 117 is added. It may be configured to select the necessary write data table. In any case, if the endian recognition of each DSP 117 and the selection of the corresponding write data table are completed at the stage of performing the halftone processing in the DSP 117, the steps S4 and S5 described in the second embodiment are performed. There is no need to carry it out again.

  DESCRIPTION OF SYMBOLS 1 ... printing system, 5 ... printing medium, 10 ... printing part, 11 ... printing head, 12 ... printing head control part, 20 ... printing medium moving part, 30 ... control part, 31 ... interface part, 32 ... CPU, 33 ... Memory, 34: Drive control unit, 35: Drive data setting unit, 40: Main scanning unit, 41: Carriage, 42: Guide shaft, 50: Secondary scanning unit, 51: Supply unit, 52: Storage unit, 53: Transport roller , 55: platen, 100: printing device, 110: personal computer (PC), 111: printer control unit, 112: input unit, 113: display unit, 114: storage unit, 115: CPU, 116: ASIC, 117: DSP , 118: memory, 119: printer interface unit, 120, 121: functional unit.

Claims (4)

An image processing method for generating print data that causes a printing apparatus to execute printing of a desired image based on image data, the image processing method comprising:
A data processing step of performing data processing for each data unit of a predetermined length based on the image data;
And a data writing step of writing the data processing result for each data processing unit based on a write data table in which write data are arranged according to the data processing result of the data processing step.
The write data table is configured based on an endian of the data processing process and an endian of an image processing system to which the data processing result is written.
The write data table includes a first write data table corresponding to the case where the endian of the data processing process and the endian of the image processing system to which the data processing result is written are the same, the endian of the data processing process, and A second write data table corresponding to the case where the end of the image processing system at the write destination to which the data processing result is written is different;
The data writing step selects either the first write data table or the second write data table in correspondence with the endian of the data processing step and the endian of the image processing system of the write destination. An image processing method comprising the steps of:   The image processing according to claim 1, wherein the data processing step is a halftone processing step of generating halftone data including data of presence / absence and / or size of dots constituting the desired image. Method. An image processing apparatus that generates print data that causes a printing apparatus to execute printing of a desired image based on image data.
A data processing unit that performs data processing for each data unit of a predetermined length based on the image data;
And a data writing unit for writing the data processing result for each data processing unit based on a write data table in which write data are arranged according to the data processing result of the data processing unit.
The write data table is configured based on an endian of the data processing unit and an endian of an image processing system to which the data processing result is written.
A first write data table corresponding to the case where the endian of the data processing unit and the endian of the image processing system of the write destination are the same as the write data table, the endian of the data processing unit and the data And a second write data table corresponding to the case where the end of the image processing system at the write destination to which the processing result is written is different.
The data writing unit selects either the first write data table or the second write data table in accordance with the endianness of the data processing unit and the endianness of the image processing system to which the data is written. An image processing apparatus characterized by   A printing system comprising the printing apparatus according to claim 3 and an image processing apparatus.

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