JP3494524B2 - Rasterizer error check method and error handling method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rasterizer / error check method and an error handling method, and is provided with a bidirectionally communicable network printer used on a network, such as a multi-function peripheral, CTR, etc. It is applicable to equipment.

[0002]

2. Description of the Related Art Printers connected to a network are
In addition to the fonts originally stored in the ROM in the printer and the fonts supplied by a card or the like, there are more and more opportunities to handle fonts downloaded via a network, and the types and number of fonts handled are enormous. By the way, when downloading fonts, use some tool for downloading.

[0003]

Although the data downloaded to the printer should be guaranteed by the tool that originally executed the download, it is difficult to predict what will happen on a wide area network. Also, as I don't know what tool is used for downloading, it is no longer the situation that the printer side does not have to check the incoming data.

The present invention has been made in view of the above circumstances and provides a method of guaranteeing the validity of downloaded font data.

[0005]

According to a first aspect of the present invention, in a printer which is used on a network and is capable of two-way communication, font data downloaded from a host or another peripheral device is compared with font data. It is characterized by checking the illegality of font data at the time of map creation, so that the correctness of the data can be confirmed at an early stage and the efficiency and safety of the entire processing can be guaranteed.

According to a second aspect of the present invention, in a printer which is used on a network and is capable of two-way communication, the font data downloaded from the host or other peripheral device is converted into font data when the font data is expanded. It is characterized by checking for injustice, so that unrecoverable errors due to data accelerator failure do not occur.

According to a third aspect of the present invention, in a printer that is used on a network and is capable of bidirectional communication, an error check is performed on font data downloaded from a host or other peripheral device, and When an irregularity is found in, the process is temporarily suspended for the emulation that is currently calling this rasterizer,
It is characterized by having the authority to prompt the release and re-downloading of illegal font data, so that even if the processing is interrupted by the illegal data, the printer will re-acquire the data by itself and continue the processing. It was designed so as not to bother you.

The invention according to claim 4 is claim 1 or claim 2.
By the error check of the above, it is characterized by giving the authority to prompt the data release and re-download in units of tables for the fonts in which the data is found to be illegal, and therefore the process for restoring the illegal data must be redone. Also,
The defective part can be replaced by the minimum unit so that the time to be lost can be reduced.

[0009]

FIG. 1 is a block diagram showing an example of a controller applied to the present invention. In the figure, 100 is a controller, 11 is a program in a program ROM 14, a mode instruction from a panel device 20, and a host device. 22
C which controls the whole controller by the command from
It is PU. Reference numeral 12 is an IC card for supplying font data or a program from the outside, and 13 is a non-volatile storage device (NVRAM) for storing the content of the mode instruction from the panel device 20. Reference numeral 14 is a program ROM in which a control program for the controller is stored, and 15 is a font RO for storing font pattern data and the like.
M and 16 are RAs used as a work memory of the CPU 11, an input buffer for input data, a page buffer for print data, a memory for download fonts, etc.
It is M. Reference numeral 17 denotes an engine interface for communicating commands and statuses with the engine 18 and print data. 18 is an engine for actually printing, 19
Is a panel interface that communicates commands and statuses with the panel device 20, and 20 is a panel device that informs the user of the current printer status and gives a mode instruction. Reference numeral 21 denotes a host interface that communicates with the host device 22, and is capable of bidirectional communication. 22 is a host device, which is a higher-level device of the printer, 2
Reference numeral 3 is a disk interface for communicating with the disk device 24, and 24 is a disk device for storing various data such as font data, programs and print data, such as a floppy disk device or a hard disk device.

[Invention 1] The present invention relates to an error handling function of a rasterizer that handles downloaded fonts. For example, when a certain font is downloaded, it is displayed in the printer as shown in FIG. It is registered with a simple structure. In FIG. 2 (A), “Header” is a “table” that collects information related to the entire font (in what order, where and what information is registered), and “Hinting inf” is character data. "Style inf" is a table that is used for correction and is shared by all characters included in the font. "Style inf" is a table that collects information indicating the character shape such as character width, line feed width, and glyphs. "G
“Lyph” is a table in which path data of each character is registered.

By the way, in order to manage fonts,
The data classification is too rough with the information of "Header" only, and the usage efficiency is poor. Therefore, a data map in which the address or offset of each data is registered is prepared for each table so that the data in each table can be taken out easily. As an example, FIG. 2B shows a data map of the “Glyph” table. In this way, if the information for each character is clear, the data can be taken out immediately when the character is expanded.

Further, for the resident font and the card font, a data map can be prepared when the printer starts up, and the data content is guaranteed by hardware. Downloaded fonts, on the other hand, must create a data map when downloaded or when first used,
The guarantee of data contents is not perfect.

The invention of claim 1 has been made in view of the above-mentioned circumstances, and when creating a data map for each table for a download font, a data check is then performed to improve data safety. It was made to let.

FIG. 3 is a flow chart for explaining the operation of the invention of claim 1, wherein the font data downloaded from the transfer source is first registered in the large classification table (S1). The position of each table is grasped from "Header" (S2), and while reading each table, a data map is created for each character (S3). At that time, the offset, the length, the data size, and the sum value are checked (S4). If an error is found, error processing is performed (S5). Through such operations, early detection and handling of data fraud is performed.

[Invention of Claim 2] According to the invention of Claim 2, a part of the data is further checked immediately before the expansion. The font data includes, in addition to the coordinate values that define the character shape, addresses and pointers that point to data points on the memory that are referred to during the expansion process.
If this value is wrong, you will access a completely unrelated place. Fr, depending on emulation
Some of them are weak in ee Memory Access, and the failure of data reference may cause an internal error.

The invention of claim 2 is made in view of the above-mentioned circumstances, and a dangerous Free Memory Access is performed by checking the access area at the time of referring to data during the expansion process for the downloaded font. This is something that is prevented in advance.

FIG. 4 is a flow chart for explaining the operation of the invention of claim 2, in which a print command is first received and font search is performed (S11). Read the Glyph with the character code of the font obtained as a result of the search (S12), "Glyp
A character shape is created based on the path information for one character extracted from "h" (S13). Then, the information for executing the specified style change is read from "Style inf" (S1).
4) The access area is checked for each data before processing is executed (S15). If there is no problem with the data, the style change is executed (S16). If there is a problem with the data, error processing is executed (S17). Furthermore, “Hinting in
The hinting information is read from f ″ (S18), and similarly, the access area is checked for each data before the processing is executed (S19). If there is no problem in the data, the hinting is executed and the character data is corrected (S20). If there is a problem with the data, error processing is executed (S21) (S1).
The operations from 1) to (S21) are repeated to create characters one by one. When all the data has been processed, it is developed in the page buffer (S22) and printed (S23). Through such an operation, safe character expansion can be performed.

[Invention of Claim 3] Claim 1 or Claim 2
In the invention of (1), when the data check is found to be incorrect, the process is normally stopped and the incorrect data is discarded. However, if an error occurs near the end of data, it will be a great waste.

According to the third aspect of the present invention, it is possible to eliminate the trouble of continuing the processing by not invalidating the processing performed until the error occurs, but by deleting the invalid data and redoing the font download by the interrupt processing. It is the one.

4 and 5 are flowcharts for explaining the operation of the invention of claim 3, for example, Hint of FIG.
It is assumed that a data error has occurred during the ing process (S19).
If an error is found in the error check of (1), the error processing of (S21) is started. FIG. 5 shows the error handling (S2
In the flowchart for explaining the outline of 1), first, for the data being executed, the process is temporarily suspended at the error occurrence point (S21a). Delete the illegal font from the memory (S
21b), the font data transmission source is instructed to re-download (S21c), and registered in the downloaded data font table (S21d). Next, the position of each table is grasped from "Header" (S21e), a data map is created for each character while reading each table (S21f), and the process returns to (C) of FIG. 4 to restart the process.
Even if the processing fails due to invalid data through such an operation, the processing can be continued by restarting from the character in which the error occurred.

[Invention of Claim 4] Similar to the invention of Claim 3, the invention of Claim 4 is intended to make it possible to continue the processing as much as possible by the restoration of the illegal data by the interrupt processing. Data is discarded with the font as one unit.
While re-downloading is executed, the invention of claim 4 is characterized in that it can be corrected in units of tables.

The operation of the invention of claim 4 will be described below with reference to the flow charts of FIGS. For example, in FIG.
Assume that a data error occurred during Hinting processing (S1
If an error is found in the error check of 9), (S21)
The error processing of is started. FIG. 6 shows the error handling (S
In the flow chart for explaining the outline of 21), first, for the data being executed, the processing is temporarily stopped at the error occurrence location (S21), and the offset of the "Hinting inf" table is read from Helder (S21 ₂ ). , an error table offset pointed to delete from the memory (S21 _3),
Instruct the font data source to download again (S21
_4), to download only the deleted table, to register on the memory (S21 _5). Then, a data map of the re-downloaded table is created again (S2
₁₆ ), returning to (E) of FIG. 4 and restarting the process (if an error occurs during the style changing process, restore the “Style inf” table and return to “D”). Through such an operation, it becomes possible to reduce the correction part and the redo process.

[0023]

According to the first aspect of the present invention, in a printer that is used on a network and is capable of two-way communication, when creating a font data map for font data downloaded from a host or other peripheral device, Although the font data is checked for injustice, there is no other font than the rasterizer that handles the data that can recognize the font data on a character-by-character basis. It guarantees efficiency and safety.

According to a second aspect of the present invention, in a printer which can be used on a network and which is capable of two-way communication, the font data downloaded from the host or other peripheral device is converted into font data when the font data is expanded. It is characterized by checking fraud. Therefore, in the printer operation, being inoperable due to an internal error is a fatal obstacle, and even if an error occurs due to invalid data, some workaround must be taken. According to the invention of claim 2, although the character shape may be disturbed, an unrecoverable error due to a data accelerator failure does not occur.

According to a third aspect of the present invention, in a printer which is used on a network and is capable of two-way communication, an error check is performed on font data downloaded from a host or other peripheral device, and When an irregularity is found in, the process is temporarily suspended for the emulation that is currently calling this rasterizer,
Since the authority to release and re-download the illegal font data has been given, even if the processing is interrupted by the illegal data, the printer will re-acquire the data independently and continue the processing, which is troublesome for the user. There is no.

The invention of claim 4 is the same as claim 1 or claim 2.
With the error check of the above, it has been made possible to give the authority to prompt the data release and re-download for each font for the font in which the data is found to be illegal, so even if the process for restoring the illegal data is redone, Since the defective part can be replaced by the minimum unit, the time to be lost can be reduced.

[Brief description of drawings]

FIG. 1 is a block diagram for explaining an example of a controller to which the present invention is applied.

FIG. 2 is a configuration diagram of a data table of a font table and a Glyph table for explaining the present invention.

FIG. 3 is a flow chart for explaining the operation of the invention of claim 1;

FIG. 4 is a flowchart for explaining the operation of the invention of claim 2;

FIG. 5 is a flowchart for explaining the operation of the invention of claim 3;

FIG. 6 is a flowchart for explaining the operation of the invention of claim 4;

[Explanation of symbols]

11 ... CPU, 12 ... IC card, 13 ... NVRAM,
14 ... Program ROM, 15 ... Font ROM, 16
RAM, 17 ... Engine interface, 18 ... Engine, 19 ... Panel interface, 20 ... Panel device, 21 ... Host interface device, 22 ... Host device, 23 ... Disk interface, 24 ... Disk device, 100 ... Controller.

Front page continuation (51) Int.Cl. ⁷ identification code FI G06F 17/21 G06F 17/21 580J (58) Fields investigated (Int.Cl. ⁷ , DB name) G06F 3/12 B41J 5/00 G06F 17 / 00

Claims (4)

(57) [Claims] 1. In a printer that is used on a network and is capable of two-way communication, font data downloaded from a host or other peripheral device is checked for illegal font data when creating a font data map. A rasterizer error check method characterized by the above. 2. In a printer that is used on a network and is capable of two-way communication, the font data downloaded from a host or other peripheral device is checked for illegal font data when the font data is expanded. Rasterizer error check method characterized by. 3. In a printer which is used on a network and is capable of bidirectional communication, an error check is performed on font data downloaded from a host or other peripheral device, and an illegality is found in the font data. At this time, the rasterizer error check method is characterized in that the emulation that is currently calling this rasterizer has the authority to temporarily suspend the process and prompt the unauthorized font data release and re-download. 4. A rasterizer characterized in that a font for which data injustice is detected by the error check according to claim 1 or 2 is given authority to prompt data release and re-download in table units. -How to deal with errors.