JPH0635442A - Data converting device - Google Patents

Abstract

PURPOSE:To convert bit data into pixel data fast by providing a conversion table for the batch conversion of a specific bit data sequence into a specific pixel data sequence. CONSTITUTION:A setting part 5 sets pixel data 'P1' corresponding to a bit '1' in the conversion table 3 and pixel data 'P0' corresponding to a bit '0' according to an instruction from a control part 4. In the conversion 3, a corresponding pixel data sequence is arranged for every 16 indexes corresponding to a 4-bit data sequence. A successive bit data sequence L1 is read out of a bit data storage part 1 and one 4-bit data is converted into a corresponding pixel data sequence at a time by the conversion table 3. Then the converted pixel data sequence is stored sequentially in a pixel data storage part 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data conversion device for converting bit data into pixel data.

[0002]

2. Description of the Related Art Conventionally, when converting bit data into pixel data based on a specified pixel value, it is inspected for each bit "1" or "0" and converted into pixel data corresponding to each of them. However, the transfer was performed, but when converting a large amount of bit data, there was a problem that conversion processing into pixel data took time. For example, in a computer equipped with a color bitmap display, when a bit image is converted into a color image and displayed, the display is slower than the display on a monochrome display.

As a technique for solving this problem,
There is JP-A-3-186980. This is because the microprocessor has an instruction that can perform the process of expanding from a bit string to a data array with one instruction, thereby reducing the number of accesses to the memory required for instruction reading and reducing the time required for instruction decoding, etc. Thus, the conversion processing can be speeded up.

[0004]

As described above, conventionally, when converting a large amount of bit data into pixel data, there has been a problem that the conversion process takes time.

It is therefore an object of the present invention to provide a data conversion device which eliminates such problems and can perform a high speed conversion process of bit data into pixel data.

[0006]

According to the present invention, in a data conversion device for converting bit data into pixel data based on a predetermined pixel value, a first storage means for storing an input predetermined bit data string is provided. , Setting means for setting the predetermined pixel value corresponding to each bit forming the bit data string, and the predetermined bit data string set by the setting means based on the value of the predetermined bit data string. It is characterized by comprising a conversion table for collectively converting into a predetermined pixel data string composed of the pixel values, and a second storage means for storing the pixel data string converted by the conversion table.

[0007]

According to the present invention, the predetermined bit data string retrieved from the first storage means comprises a predetermined pixel value corresponding to each bit of "1" or "0" forming the bit data string. It is collectively converted by a conversion table having all combinations of predetermined bit data strings, and the converted pixel data strings are stored in the second storage means.
In addition, each bit that constitutes the predetermined bit data string
The predetermined pixel value corresponding to 1 "or" 0 "can be set and changed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a data conversion device that is a first embodiment of the present invention. In FIG.
The data converter includes a bit data storage unit 1 in which bit data to be converted is stored, a conversion table 3 for collectively converting a predetermined number of bit data into a pixel data string, and a pixel data string collectively converted by the conversion table 3. It is composed of a pixel data storage unit 2 for storing, a setting unit 5 for setting a value of pixel data corresponding to bit data in the conversion table 3, and a control unit 4 for performing overall control such as reading and writing of data.

FIG. 2 is a diagram for explaining a data conversion device for collectively converting 4-bit data into a pixel data string. That is, the predetermined bit data string in FIG. 1 is 4 bits, and the converted pixel data string is the pixel data string L2 corresponding to the 4-bit data string L1. In FIG. 2, the setting unit 5 sets pixel data “P1” corresponding to the bit “1” and pixel data “P0” corresponding to the bit “0” in the conversion table 3 based on the instruction from the control unit 4. I'll do it. In this embodiment, the value of one pixel to be converted is 8 bits. In FIG. 2, the conversion table has 16 indexes corresponding to a 4-bit data string, and a corresponding pixel data string is arranged for each of these 16 indexes. Therefore, one piece of 4-bit data of a continuous bit data string read from the bit data storage unit 1 is represented by 4-bit data information, for example, the pixel data string “P1, P1” corresponding to the index “1011”.
0, P1, P1 ". Then, the converted pixel data string “P1, P0, P1, P1”
Are sequentially stored in the pixel data storage unit 2.

FIG. 3 is a conversion flowchart of the data conversion device. In FIG. 3, first, the setting unit 5 sets the pixel data “corresponding to the bit data“ 1 ”and“ 0 ””.
Change the settings of P1 "and" P0 "(step 3
1). Then, the 4-bit data string is read from the bit data storage unit 1 (step 32), and the 4-bit data string is inspected (step 33). Next, a pixel data string is extracted from the conversion table 3 based on the inspection index in step 32 (step 34). Then, the converted pixel data string is stored in the pixel data storage unit 2 (step 35). Finally, it is determined whether or not there is a further 4-bit data string (step 36), and if there is a 4-bit data string, the process proceeds to step 31,
Further, the 4-bit data is converted into pixel data, and when there is no 4-bit data string, the processing is ended.
Note that the pixel data value in the conversion table can be changed only in two types of bit data “1” and “0”, so the change time can be short.

In this way, since the conversion from bit data to pixel data is carried out collectively for a predetermined number of bits, the conversion processing can be speeded up.

[0012]

As described above, according to the present invention, the predetermined bit data string retrieved from the first storage means corresponds to each bit of "1" or "0" forming this bit data string. Since the conversion table having all the combinations of the predetermined bit data strings composed of the predetermined pixel values is collectively converted, there is an advantage that the bit data can be converted into the pixel data at a high speed.

Further, the conversion speed can be further increased by setting the optimum batch conversion amount in consideration of the characteristics of the conversion data and the change time of the pixel data value of the conversion table when the data conversion apparatus is used. Has the advantage that

[Brief description of drawings]

FIG. 1 is a configuration block diagram of a data conversion device that is a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a data conversion device that collectively converts 4-bit data into a pixel data string.

FIG. 3 is a conversion flowchart of the data conversion device.

[Explanation of symbols]

1-bit data storage unit 2 Pixel data storage unit
3 conversion table 4 control unit 5 setting unit L1 bit data string L2
Pixel data string

Claims (1)

[Claims] 1. A data conversion device for converting bit data into pixel data based on a predetermined pixel value, comprising first storage means for storing an input predetermined bit data string, and the bit data string. Setting means for setting the predetermined pixel value corresponding to each bit, and a predetermined pixel having a pixel value set by the setting means for the predetermined bit data string based on the value of the predetermined bit data string A data conversion device comprising: a conversion table for collectively converting into a data string, and a second storage means for storing the pixel data string converted by the conversion table.