JPH01269124A - Photographic printer - Google Patents

Abstract

PURPOSE:To synthesize a signal to input without having a picture memory and to obtain a picture hard copy by storing and operating picture element data with two pairs of the shift register, sending the result into a buffer memory and executing the photographic printing. CONSTITUTION:The title printer is composed of an A/D converter 1 to binarize a video signal, registers 2 and 3 to temporarily store digital data, a counter 4 to designate the position to fetch a picture, a switch 5 to switch the contents to pass directly the and the contents to pass the arithmetic result for the contents of a shift register 2, a computing element 6 to execute the operation such as interpolarion, a memory 7 to store the data of plural lines, a processing part 8 to generate the address control signal of the memory, a circuit 9 to generate a clock synthesized to a synthesizing signal, a data processing part 10 to execute the photographic printing and a part 11 to photographic-print. Thus, the photographic printing synthesized to the inputted video signal can be executed.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is mainly applicable to personal computers, televisions, VTRs, etc.
The present invention relates to a printing device for hard copying video signals of still videos, laser discs, etc.

[Prior Art] Conventional printing devices that hard copy video signals from personal computers and the like temporarily store digitized video signals in an image memory, read out the contents of the memory in accordance with the speed of the printing device, and then print. Common. Furthermore, in systems without memory, it is common to have two sets of buffer memories and print while synchronizing with each other.

[Problems to be Solved by the Invention] In order to further simplify the system described above and perform printing in synchronization with the input video signal, processing such as interpolation of the number of printing lines, padding, data correction, etc. In order to carry out printing with a simplified system, it is important to keep memory to a minimum.

[Means to solve the problem]

The printing apparatus according to the present invention stores and calculates pixel data using two sets of shift registers, and sends the results to a buffer memory for printing.

[Embodiment] Fig. 1 is a block diagram showing an embodiment of the present invention, Fig. 2 is a diagram for explaining the present invention on a screen, and Fig. 3 is a timing chart of the embodiment. It is a diagram. In Figure 1, A/D1 is an A/D converter that binarizes the video signal, shift register 2 and shift register 3 are registers that temporarily store digital data, and counter 4 is for specifying the position to capture the screen. SW5 is a switch for switching between passing the contents of the shift register 2 directly and passing the calculation results, the computing unit 6 is a computing unit that performs calculations such as interpolation, and the memory 7 is used as a line buffer. A memory for storing multiple lines of data for printing, an address processing section 8 for generating memory address control signals, a clock 9 for generating a clock synchronized with a synchronization signal, and a printing processing section 10 for printing. The data processing unit and mechanism 11 are the parts that print images.

This will be explained in detail according to the signal flow. The input analog video signal is selected according to the color to be printed and input to one A/D converter (not shown), where it is converted into digital data. For example, the shift register No. 2 is composed of 5 x 6 bits and continuously takes in data of 5 pixels and 6 bits, that is, 5 pixels lined up horizontally in the diagram of a screen such as a CRT as shown in Fig. 2. (5 points horizontally and vertically l) The data of the horizontal scanning line of the primary line (2 horizontally 2 vertically)
is taken in again, and the data of both lines are stored in the shift registers 2 and 3. From the contents of the 0 and 0 data, the arithmetic unit 6 performs arithmetic processing such as vertical line interpolation and horizontal position correction. These calculation processes are performed during the period up to the sampling period of the primary line, and are transferred to the next stage memory 7 by then. In the memory 7, the data of the calculation results is written from the shift register and the data is transferred to the print processing circuit lO. Perform appropriate readings on a timeshare. This memory address control is performed by eight processing circuits. Further, address processing is performed by a clock generation circuit 9 according to an input synchronization signal.

The order of the printing process in Fig. 2 is as follows: 5 dots are sampled from each line according to horizontal scanning, and when it reaches the bottom in the vertical direction, the next vertical line 2 is started.
Due to computational processing considerations, sampling may be performed on overlapping vertical lines. The memory 7 temporarily stores the data as a 5-line or 4-line buffer in the vertical direction. When sampling is completed from left to right in the vertical direction, one color in the print is completed, and the next color is executed by changing the color signal of the input video signal. Generally, one sheet of printing is completed by repeating the three colors sequentially.

FIG. 3 shows a timing chart in the block diagram of FIG. 1. A is a horizontal synchronizing signal, and the input into the shift register is performed in synchronization with the horizontal period. B's 5 (nl
, sfn+ 1), and S(n+ 2) indicate the timing of loading into the shift register and change depending on the loading location.The counter 4 is responsible for controlling this position. Indicates the operable period, D indicates the transfer period from the shift register to the memory,
T(m), T(m+1), and T(m+2) are periods during which transfer is possible, and are determined from a period during which data can be written into the memory 7 from printing processing. Transfer is performed when arithmetic processing is completed during this period. Therefore, the calculation period of C must be completed with one transfer period of D remaining. Under this condition, continuous sampling is performed.

In this embodiment, the sampling number is 5 pixels at a time, but depending on the printing speed and the memory configuration, sampling may be performed for any number of pixels.
It can be configured similarly. Further, in the embodiment, an example in which three color planes are sequentially used is shown, but the same effect can be obtained even if the switching is performed line sequentially. Also, if a latch circuit is placed in front of the memory, there will be more margin for transfer to the memory, which can be considered similarly.

[Effects of the Invention] As explained above, the present invention makes it possible to obtain a hard copy of the screen by synchronizing with input signals without having a screen memory.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a printing apparatus according to the present invention. FIG. 2 is a diagram illustrating the present invention in detail. FIG. 3 is a timing chart diagram explaining the present invention in detail. ■...A/D converter 2.3...Shift register 6...Calculating unit 7...Buffer memory 11...Printing mechanism and above Applicant Seiko Epson Co., Ltd. Agent Patent attorney Suzu Kisanbe (1 person) 2nd A

Claims (1)

[Claims] An A/D converter that digitizes the input video signal, two sets of shift registers that store multiple pixels at high speed, an arithmetic unit that performs calculations based on the contents of the shift registers, and generates addresses for loading the shift registers. A group of counters, a memory that stores calculation contents and also serves as a buffer for printing;
A printing device comprising a counter group for controlling memory addresses, etc., a processing circuit group for printing the contents of the memory, and a printing mechanism, and printing in synchronization with an input video signal.