JP2000025279A - Band scan type raster plotter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a print wait time and improve a print speed by increasing a data process speed. SOLUTION: A band scan type raster plotter 2 divides an image output area of one page to a plurality of bands, develops vector data of image information to be output to a bit map memory 8 in a form of raster data for every band, and outputs the image information developed to the bit map memory 8 to a head 10 for every band. The bit map memory 8 when the vector data is developed to the bit map memory 8 is prepared by a maximum capacity necessary for the plotter. A height of the bands is changed according to a print condition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a band scan type raster plotter / printer for developing vector data to be output as raster data and outputting the raster data.

[0002]

2. Description of the Related Art When an input vector data is developed as raster data and output as an image to an image output device such as a raster plotter, the rasterized result of analysis is stored in an image memory having a capacity corresponding to one sheet of data. There are a full bitmap type for expanding data and a banding type for expanding raster data to an image memory having a capacity equivalent to band data obtained by dividing one sheet of data into several bands. In the latter banding type, for example, a banding memory having a capacity of two bands is used as an image memory, and raster data developed through an intermediate code in one banding memory is printed for one band while the other banding memory is printed. The operation of expanding raster data in the banding memory via the intermediate code is repeated. For example, when printing on A1 paper at a resolution of 400 dpi, the former requires 16
Although a large capacity corresponding to MB is required, the latter has an advantage that if the width of one band is 128 dots, the capacity required for the banding memory is 150 KB per band, and the total capacity is 300 KB.

[0003]

However, in the above-described conventional banding-type image output apparatus, the resolution (for example, 720 × 720 dpi, 360 × 360 dpi) is required.
, And the use of ink (switching between CMYK four colors and K1 color) has been processed with a constant bandwidth. Therefore, since raster data development processing is performed in band units, even for a band including many blank portions that are output with the ink K1 color at a resolution of 360 × 360 dpi, the entire banding memory for one band is allocated. For this reason, most of the memory is consumed for a lot of blank information, and there is a problem that the efficiency of use of the memory is low and that it takes time to clear data. In addition, in the conventional system, the amount of data that can be
For example, since it is limited to one band, if the number of intermediate codes in the next band is large or the amount of raster data to be developed is large, even if printing of one band is completed, Is not completed, and the image output apparatus stops outputting (so-called conceived state), which causes a problem that the printing speed is reduced.
SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and provides a band scan type raster plotter that can change a band height according to printing conditions (analysis degree / number of inks used) and reduce a waiting time. It is intended for.

[0004]

In order to achieve the above-mentioned problem, the present invention divides an image output area for one page into a plurality of bands and rasterizes vector data of image information to be output for each of the bands. A bitmap memory for developing vector data in a bitmap memory in a band scan type raster plotter that develops data in a bitmap memory in the form of data and outputs the image information developed in the bitmap memory for each band. The maximum capacity required for the plotter is provided, and the height of the band is changed according to the printing conditions.

[0005]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In FIG.
(1) is a host device, which outputs image information such as design drawings created using an input device (not shown) to a raster plotter (2) in the form of vector data. The raster plotter (2) converts vector data sent from the host device (1) into raster data and prints out the raster data.

[0006] Vector data transmitted from the host device (1) is taken into the RAM (4) via the interface (3) having a FIFO buffering function.
The CPU (5) performs, based on a program stored in the ROM (6), division processing, sort processing, and the like for the vector data stored in the RAM (4) using a preset bandwidth and block width. Preprocessing is performed to arrange vector data included in each block of each band into an intermediate code format (for example, vector data).

[0007] The image processor (7) sequentially converts the image data in the intermediate code format stored in the RAM (4) into a D code.
The DA processing is performed, and the raster data is developed in the bit map memory (8). The raster data developed in the bitmap memory (8) is sequentially sent to the head (10) via the head driving device (9) and printed by the band scanner method.

FIG. 1 shows a paper (1) using a raster plotter (2).
1) shows a band to be printed. The whole image is divided into a plurality of bands, and the image of each band is
The image is printed on a sheet with a width corresponding to the length in the longitudinal direction of 0). Next, the band height adjustment processing operation will be described.

The maximum drawing width is 905 mm and the resolution is 720.
dpi, the number of nozzles of the inkjet head (10) is 64
In an ink-jet plotter using four colors of CMYK (cyan, azenda, and yellow black), the maximum capacity of the bitmap memory (8) required for the plotter is (905 / 25.4 × 720 × 64). × 4)
/ 8 = 820913 bytes, which is about 800 KB.

Here, one inch is calculated as 25.4 mm, and the whole is divided by 8 in order to convert bits into bytes (1 byte = 8 bits). The CPU (5) prepares a bitmap memory (8) for developing vector data into a bitmap, with a maximum capacity necessary for the plotter, that is, 800 KB in the present embodiment.

The CPU (5) divides the vector data stored in the RAM (4) into bands according to the maximum capacity of the bitmap memory (8). 720 dpi, CM
Assuming that the height of the band (B1) of four colors of YK is one band width, 360 dpi, 400 KB for four colors of CMYK
From the formula of × 2, the height of the band (B2) is set to twice the double band width. 100 KB for 360 dpi, K1 color
From the formula of × 8, the height of the band (B3) is set to be eight times the bandwidth. Thus, the band (B2) depends on the printing conditions.
By making the height of (B3) twice or eight times, the number of bands of an image for one page can be reduced and data processing can be performed at high speed.

[0012]

Since the present invention is constructed as described above, it is possible to perform data processing at a high speed, to reduce the data processing waiting time and to increase the printing speed.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of the present invention.

FIG. 2 is a block diagram illustrating a raster plotter.

[Brief description of reference numerals]

 DESCRIPTION OF SYMBOLS 1 Host apparatus 2 Raster plotter 3 Interface 4 RAM 5 CPU 6 ROM 7 Image processor 8 Bit map memory 9 Head drive unit 10 Head 11 Paper B1 band B2 band B3 band

Claims (1)

[Claims] 1. An image output area for one page is divided into a plurality of bands, vector data of image information to be output is developed in a bitmap memory in the form of raster data for each of the bands, and stored in the bitmap memory. In a band scan type raster plotter that outputs developed image information for each band, a maximum capacity required for the plotter is provided with a bitmap memory for developing vector data into a bitmap memory, and the height of the band is determined by printing conditions. A band scan type raster plotter characterized by changing the color.