JP7243172B2 - Image processing device - Google Patents

Description

The present invention relates to an image processing apparatus.

In Patent Document 1, internal An SOC is disclosed that performs job control so as to suppress power consumption and maintain performance to some extent without exceeding the withstand voltage of the package.

Japanese Patent Application Laid-Open No. 2007-157068

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image processing apparatus capable of controlling the amount of heat generated by the apparatus to be below the upper limit while suppressing deterioration in quality even when a plurality of related processes are executed simultaneously.

The image processing apparatus according to the first aspect includes a plurality of processing units that execute a series of processes related to predetermined image processing, and a total power consumption of the plurality of processing units that is equal to or less than a predetermined threshold. a control unit for controlling the processing capacity of at least one of the plurality of processing units, wherein the control unit selects at least one means from a plurality of means for reducing the throughput of processing in the processing unit, and The means described above lowers the processing capacity and controls the total power consumption to be equal to or less than a predetermined threshold value.

An image processing apparatus according to a second aspect is the image processing apparatus according to the first aspect, wherein the plurality of means includes means for reducing the throughput by increasing the number of clocks required for processing in the processing section. It is.

An image processing apparatus according to a third aspect is the image processing apparatus according to the second aspect, wherein the control unit decreases the throughput by increasing the number of clocks required for processing one pixel.

An image processing apparatus according to a fourth aspect is the image processing apparatus according to the first aspect, wherein the plurality of means reads the image information from a storage unit storing the image information to be subjected to the image processing. and means for reducing the amount of image information read out per unit time to reduce the throughput.

An image processing apparatus according to a fifth aspect is the image processing apparatus according to the fourth aspect, wherein the control unit increases a readout interval when reading each unit information amount determined in advance from the storage unit, and to reduce the amount of said image information read out in the first step.

An image processing apparatus according to a sixth aspect is the image processing apparatus according to the fourth aspect, wherein the control unit reduces the unit information amount when read out from the storage unit for each predetermined unit information amount, and It reduces the amount of image information read out per time.

An image processing apparatus according to a seventh aspect is the image processing apparatus according to the first aspect, wherein the plurality of means includes at least one parallel processing of a plurality of parallel processing units that perform parallel processing of one processing and another parallel processing. means for reducing said throughput by having it run after is completed.

An image processing apparatus according to an eighth aspect is the image processing apparatus according to any one of the first to seventh aspects, wherein the total power consumption is calculated according to the received image processing content, and the calculated total power consumption is calculated. The control unit further includes a determination unit that determines whether power exceeds the threshold, and the control unit determines that the total power consumption exceeds the threshold if the determination unit determines that the total power consumption exceeds the threshold. It is controlled so that it becomes equal to or less than the threshold value.

An image processing apparatus according to a ninth aspect is the image processing apparatus according to the eighth aspect, wherein when the determination unit determines that the total power consumption exceeds the threshold value, the determination unit determines Priorities are given to the plurality of means according to the results, and at least one means is selected from the plurality of means according to the priorities.

According to the first aspect, it is possible to provide an image processing apparatus capable of controlling the amount of heat generated by the apparatus to be equal to or lower than the upper limit while suppressing deterioration in quality even when a plurality of related processes are executed simultaneously. Effective.

According to the second mode and the third mode, there is an effect that the throughput of processing can be lowered regardless of access to the storage unit.

According to the fourth, fifth, and sixth modes, there is an effect that fine adjustment of the degree of decrease in throughput can be performed.

According to the seventh aspect, there is an effect that the throughput can be reduced in units of a large degree of reduction.

According to the eighth aspect, compared to the case where the total power consumption is controlled to be equal to or less than a predetermined threshold during image processing, the total power consumption can be controlled to be equal to or less than the threshold more reliably. It has the effect of

According to the ninth aspect, it is possible to select at least one means from a plurality of means in a shorter time than when the plurality of means are not given priority.

1 is a block diagram showing an example of the configuration of an image processing device according to an embodiment; FIG. 1A is a configuration diagram, FIG. 1B is a diagram for explaining a reduction in peak power value, and FIG. FIG. 8A is a configuration diagram, FIG. 9B is a diagram for explaining the reduction of peak power value, and FIG. FIG. 9A is a configuration diagram, FIG. 1B is a diagram for explaining a reduction in peak power value, and FIG. 7 is a flow chart showing the flow of processing of a peak power reduction processing program according to the embodiment; FIG. 4A is a diagram for explaining temporal changes in power in image processing of the image processing apparatus according to the embodiment, FIG. (c) is a diagram showing a comparison between the power shown in (b) and the allowable power amount.

Hereinafter, with reference to FIGS. 1-6, the form for implementing this invention is demonstrated in detail.
In the present embodiment, in the image processing apparatus according to the present invention, image processing corresponding to the operation mode is performed on image information (image data) input from the image reading apparatus, and processing for outputting to the image forming apparatus is performed. A case will be described as an example. It should be noted that the “operation mode” referred to in the present embodiment refers to the content of processing specifically executed in the image processing apparatus 10 .

As shown in FIG. 1, the image processing apparatus 10 according to the present embodiment includes an image input unit 12, an image processing unit 14, an image output unit 16, and storage units 18, 20, 22 (in FIG. 1, DDR (Double data rate)). FIG. 1 also shows a scanner 50 as an image reading device and a printer 52 as an image forming device as devices related to the image processing device 10 .

The image input unit 12 is an interface for inputting image information read by the scanner 50, and is sometimes called an IIT (Image Input Terminal). Below, the processing in the image input unit 12 may be referred to as “IIT processing”.

The image output unit 16 is an interface that outputs the image information processed by the image processing unit 14 to the printer 52, and is sometimes called an IOT (Image Output Terminal). Below, the processing in the image output unit 16 may be referred to as “IOT processing”.

The image processing unit 14 is a unit that performs predetermined processing such as noise removal on image information input via the image input unit 12 . Hereinafter, the term "image processing" simply refers to this predetermined processing in the image processing section 14. FIG. The image processing device 10 typically performs multiple types of image processing. Each image processing is centered on memory-to-memory processing in which image information is read out from a storage unit, processed, and the processed result is stored in the storage unit.
In that sense, the processing in the image processing unit 14 may be hereinafter referred to as "copy processing". In this embodiment, a plurality of processes are assumed as image processing, but a single process may of course be used.

The storage unit 18 is storage means used when transferring image information between the image input unit 12 and the image processing unit 14 . The storage unit 22 is storage means used when transferring image information between the image processing unit 14 and the image output unit 16 . The storage unit 20 is storage means for storing execution results of each process performed by the image processing unit 14 . Although the form of the storage units 18, 20, and 22 is not particularly limited, a DDR system memory is used as an example in the present embodiment.

In addition to the above components, the image processing apparatus 10 includes a CPU for controlling each of the image input unit 12, the image processing unit 14, the image output unit 16, and the storage units 18, 20, 22, and a peak power reduction process (to be described later). A ROM for storing programs and various control programs, a RAM for developing the program when the peak power reduction processing program is executed, and the like are provided.

Here, a process of reducing a peak value (hereinafter referred to as "peak power") of power consumption (hereinafter referred to as "power") consumed by processing in the image processing apparatus 10 executed by the image processing apparatus 10 will be described.

There is a natural limit to the amount of power consumed by electrical equipment, not just image processing devices. The interior of an electrical device is generally divided into a plurality of processing units each executing a predetermined process. In general, the allowable power (hereinafter referred to as "allowable power amount") differs for each processing unit. If the allowable power level is exceeded in a specific processing unit, problems such as malfunction and damage will occur in that processing unit.

In order to solve the above problems, conventionally, the following measures have been taken. That is, the first measure is to release heat generated by excessive power. More specifically, heat is released by using, for example, a heat sink, a fan, a package with high heat dissipation performance, or the like. The second measure is a measure that does not generate heat. More specifically, power gating (control of power supply/cutoff), clock gating (control of clock signal supply/cutoff), or the like is used to stop part of the processing unit to suppress heat generation.

However, the first measure has the problem of increased cost due to the additional members. In addition, the second measure is not suitable for fine control, leading to the problem of complication of software. Therefore, as a third measure, even if all the processing units operate simultaneously, a measure may be taken to reduce the number of copying processes so that the heat tolerance is not exceeded. However, in this case, since the originally necessary processing is omitted, the image quality and functions may be degraded.

Therefore, in the present embodiment, an operating processing unit (hereinafter sometimes referred to as a "module") is specified, and the operating module is controlled so that the power (that is, the amount of heat generated) does not exceed the allowable amount. More specifically, at least one means is selected from a plurality of means for reducing the throughput of processing in the processing units, the selected means reduces the processing capacity, and the peak power of the total power of the plurality of processing units is predetermined. We decided to control it so that it would be below the threshold (permissible power amount) set. As a result, it is possible to provide an image processing apparatus capable of controlling the amount of heat generated by the apparatus to be equal to or lower than the upper limit while suppressing deterioration in quality even when a plurality of related processes are executed simultaneously. It should be noted that "throughput" generally means processing capacity per unit time.

The peak power control according to the present embodiment will be specifically described with reference to FIG. FIG. 6 assumes "IIT processing", "copy processing", and "IOT processing" as processing in the image processing apparatus 10, and shows temporal changes in the flow of processing and temporal changes in power. IIT processing and IOT processing are “real-time processing” as shown in FIG. It is "non-real-time processing" in the sense that it is executed according to the scheduling set by the unit (CPU).

FIG. 6A shows three sheets of recording media (hereinafter referred to as "sheets") on which images are formed, indicated by "p1", "p2", and "p3", at intervals indicated by "pages". are sequentially read by the scanner 50 (IIT processing), the read image information of p1, p2, and p3 are subjected to copy processing, then IOT processing is performed, and the printer 52 sequentially prints them. is shown.

FIG. 6(b) is a diagram showing the power in each process of the IIT process, the copy process, and the IOT process. FIG.6(c) is the figure which accumulated the electric power of FIG.6(b) in each time, and showed it. In the present embodiment, as shown in FIG. 6(c), time-series data of accumulated power is compared with the allowable power amount to determine whether the peak power is equal to or less than the allowable power amount.

It should be noted that the throughput of the processing unit should be lowered as a result, so the method for lowering the throughput is not particularly limited, but the following three methods are used as examples in the present embodiment. . In each of the following methods, copy processing is assumed as processing in the image processing unit 14, and the throughput of the module executing the copy processing is lowered so that the total power does not exceed the allowable power amount. In other words, the operating power of each module is known in advance, and if the peak value of the total power of the operating modules (peak power) is predicted to exceed the power capacity, the throughput of one of the modules is reduced. to reduce peak power.

<First method>
A first method of reducing throughput will be described with reference to FIG. In this method, as processing units to be controlled, three processing units 1, 2, and 3 are assumed as shown in FIG. The processing unit 1, the processing unit 2, and the processing unit 3 are part of a plurality of processing units (for example, 20 to 30 types of processing units) of the image processing apparatus 10. FIG. Each process of the processing section 1, the processing section 2, and the processing section 3 reads image information from the memory 24 (indicated by "R" in FIG. 2A), executes predetermined processing, and performs processing. The execution result is written in the memory 24 (denoted as "W" in FIG. 2(a)). The details of the processing in the processing unit are specified using, for example, "data amount", "throughput", and "processing time". The original (before throughput drop) data amount, throughput, and processing time of each of the processing units 1, 2, and 3 are as shown in FIG. 2(c). Examples of units of data amount, throughput, and processing time are [bytes], [bytes/second], and [seconds].

In this method, the time required for processing is lengthened and the throughput is lowered. More specifically, for example, the number of clocks required for processing one pixel included in the image information is increased to lower the throughput. As shown in FIG. 2(c), in this example, the processing times of the processing unit 1, the processing unit 2, and the processing unit 3 are Time1, Time2, and Time3, respectively. Time2<Time3. In this example, as shown in FIG. 2(b) <2>, the peak power exceeds the allowable power amount.

Therefore, in this method, as shown in FIG. match the For example, if originally Time1 = (1/2) Time3, Time2 = (2/3) Time3, and Time3 = 1, then Time1 is doubled to 1, and Time2 is multiplied by 3/2 to 1. and In this case, the throughput of the processing unit 1 is 1/2 times the original capacity, and the throughput of the processing unit 2 is 2/3 times the original capacity.

As a result of carrying out the above, the total power of the processing units 1, 2, and 3 is as shown in <4> of FIG. 2B, and even the peak power of the total power is below the power allowance. As a result, the power consumption inside the module and the power consumption of the data transfer section with the memory 24 in the module can be reduced. This method has the advantage that the throughput can be reduced independently of accesses to the memory 24 .

<Second method>
A second method of reducing throughput will be described with reference to FIG. In this method, the number of modules in copy processing is reduced to lower the throughput. That is, some copy processes improve processing performance by operating a plurality of pieces of hardware having the same function at the same time. When the peak power of the image processing apparatus 10 exceeds the allowable power amount, in the processing using a plurality of modules simultaneously, the operation of some of the modules is extended to become serial processing. As a result, the power of the target module is suppressed, and the peak power of the entire image processing apparatus 10 is controlled to be equal to or less than the permissible power amount.

In this example, as shown in FIG. 3A, the processing section 2 includes a processing section 2-1 and a processing section 2-2. The processing unit 2-1 and the processing unit 2-2 are made of the same hardware. Write. The original data amount, throughput, and processing time of each processing unit are as shown in FIG. 3(c).

As shown in FIG. 3B <1>, in this example, the processing unit 2 performs parallel processing, and as shown in FIG. surpassed. Therefore, as shown in FIG. 3(c), the processing of one side of the processing unit 2 is extended first so that it becomes serial processing. In this case, the processing time of the processing unit 2 is from Time2 to 2×Time2 (throughput is (1/2)·TP2). As a result, the peak power of the image processing apparatus 10 is suppressed below the permissible power amount as shown in FIG. 3B <4>. In the example of FIG. 3(b) <3>, 2×Time2>Time3, and the total processing time is longer than the original processing time. may be controlled so as to be within the initial processing time by the method of .

In the present embodiment, a method of reducing throughput by changing part of parallel processing to serial processing has been described as an example, but the method is not limited to this. Throughput may be reduced by executing the entire process. This method lowers the throughput in units of parallel processing, so it is an effective method when it is desired to greatly lower the throughput at once.

<Third method>
A third method of reducing throughput will be described with reference to FIG. In this method, throughput is lowered by reducing the transfer amount of image information in copy processing in some modules. As shown in FIG. 4A, the configuration of the processing unit is the same as the processing unit shown in FIG. 2A, and the original data amount, throughput, and processing time in each process are also the same.

When reading data from the memory 24 in a certain module, a request signal RD_REQ is issued to the memory 24 via a bus (not shown) as shown in FIG. 4(b) <1>. A data amount TD (number of bytes) to be transferred is attached to the request signal RD_REQ.
In response to the request of the request signal RD_REQ, the data of the specified data amount TD is sent from the memory 24 to the module as the data signal RD_DATA. In this example, as shown in FIG. 4(b) <3>, the data amount TD is kept constant and the interval of the request signal RD_REQ (indicated as "REQ interval" in FIG. 4(b)) is lengthened. This reduces the amount of data transferred per unit of time, thus reducing the throughput of the module. The example shown in FIG. 4(b) <4> shows an example in which this method is applied to the processing units 1 and 2, resulting in an increase in Time1 and Time2 and a decrease in throughput TP1 and TP2. are doing.

In the present embodiment, an example has been described in which the amount of data TD to be transferred is constant and the REQ interval is lengthened. '(<TD). This also reduces the amount of data transferred per unit time, thereby reducing the throughput of the module. This method and the method described above have in common that the throughput is reduced by preventing the abundant flow of data. Since this method changes the REQ interval or the amount of data to be transferred TD, it is possible to fine-tune the reduction in throughput.

Next, peak power reduction processing executed in the image processing apparatus 10 will be described with reference to FIG. FIG. 5 is a flow chart showing the processing flow of the peak power reduction processing program. This program is stored, for example, in a storage means such as a ROM (not shown) of the image processing apparatus 10. A CPU (not shown) reads this program from the storage means, develops it in a RAM or the like, and executes it.

As shown in FIG. 5, in step S100, the operation module in the current operation mode (denoted as "mode" in FIG. 5) is confirmed. The operation mode, as described above, refers to the content of the processing specifically executed in the image processing apparatus 10, and is set according to the user's instruction, for example. The operation modules refer to, for example, the processing section 1, the processing section 2, and the processing section 3 described above.

In step S102, peak power is calculated. More specifically, in the image processing apparatus 10, power consumption for each mode of each module is stored in advance in storage means such as a ROM. Then, the CPU obtains the power of each module corresponding to the set mode from the ROM and totals them to calculate the peak power.

In step S104, it is determined whether or not the peak power calculated in step S102 exceeds the allowable power amount. If the determination is negative, the peak power reduction processing program is terminated, and if the determination is positive, the process proceeds to step S106.

In step S106, the order of execution of a plurality of throughput reduction methods (for example, the above-described first method, second method, and third method) is determined. As an example, the execution order may be created in a table format. The execution order of the throughput reduction methods may be set so that, for example, the quality of image processing (e.g. image quality) is executed in descending order of effect on functions, or in descending order of effect on overall processing time. You can set it to run.

In step S108, the throughput lowering method with the highest order is executed first.

In step S110, it is determined whether or not the peak power is equal to or less than the allowable power amount as a result of execution of step S108. If the determination is affirmative, the peak power reduction processing program is ended, and if the determination is negative, the process proceeds to step S108 to execute the next throughput reduction method. Note that steps S106 to S110 are processes for determining a throughput reduction method for a specific processing unit so that the peak power is within the allowable power amount. It is a preprocessing that is executed before performing

By the above process, when various processes are executed in the image processing apparatus 10, the peak power is suppressed to the allowable power amount or less.

In the above-described embodiment, the method of reducing the throughput in consideration of the power consumption of each processing unit corresponding to the operation mode before actual processing in the image processing apparatus 10 has been exemplified and explained, but the present invention is not limited to this. do not have. Although the peak power did not exceed the allowable power amount immediately after executing the image processing, if the peak power exceeds the allowable power amount due to the influence of heat, for example, as the image processing progresses, Peak power may be reduced by reducing the throughput of one of the processing units.

1, 2, 3 Processing unit 10 Image processing device 12 Image input unit 14 Image processing unit 16 Image output units 18, 20, 22 Storage unit 24 Memory 50 Scanner 52 Printer TD Data volume

Claims (7)

a plurality of processing units that execute a series of processes related to predetermined image processing; a control unit for controlling processing capacity,
The control unit selects at least one means from a plurality of means for reducing processing throughput in the processing unit, and reduces the processing capacity by the selected means so that the total power consumption is equal to or less than a predetermined threshold. controlled to be
The image processing apparatus, wherein the plurality of means includes means for reducing the throughput by increasing the number of clocks required for processing in the processing section. The image processing apparatus according to Claim 1, wherein the control unit reduces the throughput by increasing the number of clocks required for processing one pixel. a plurality of processing units that execute a series of processes related to predetermined image processing; a control unit for controlling processing capacity,
The control unit selects at least one means from a plurality of means for reducing processing throughput in the processing unit, and reduces the processing capacity by the selected means so that the total power consumption is equal to or less than a predetermined threshold. controlled to be
When the image information to be processed is read from a storage unit storing the image information to be subjected to the image processing, the plurality of means reduce the amount of the image information to be read per unit time to lower the throughput. image processing apparatus comprising means. 4. The image processing apparatus according to claim 3 , wherein the control unit lengthens a readout interval when reading each predetermined unit amount of information from the storage unit to reduce the amount of the image information read out per unit time. 4. The image processing according to claim 3 , wherein the control unit reduces the amount of the image information read out per unit time by reducing the unit information amount read from the storage unit for each predetermined unit information amount. Device. further comprising a determination unit that calculates the total power consumption according to the content of the received image processing and determines whether the calculated total power consumption exceeds the threshold;
6. Any one of claims 1 to 5 , wherein the control unit controls the total power consumption to be equal to or less than a predetermined threshold when the determination unit determines that the total power consumption exceeds the threshold. 1. The image processing apparatus according to claim 1. When the determination unit determines that the total power consumption exceeds the threshold value, the control unit gives priority to the plurality of means according to the determination result of the determination unit, and according to the priority, 7. The image processing apparatus according to claim 6 , wherein at least one means is selected from a plurality of means.

Images