JPH07154735A - Video printer - Google Patents

Abstract

PURPOSE:To enable high-speed and high-quality printing by reading video data from an image memory during a video data output term, outputting them on a monitor, continuously reading the pixel data of vertical picture elements corresponding to the same horizontal picture element number from the image memory during a print data output term by just one line and transferring those data. CONSTITUTION:During a print operation term, an output data switching signal is turned to a low level in the cycle twice the vertical synchronizing signal, for example, and within this term, print data are continuously read from a memory 21. When reading is completed, the switching signal is turned to a high level, and first and second video data are read from the memory 21 synchronously with video output timing. Next, the print data in the twice cycle are read from the memory 21 matching two vertical synchronizing signal cycles, when a print operation is completed, the switching signal is automatically turned to the high level at all times, and the transfer of print data is finished as well. Afterwards, the video data and print data read out while sharing time are inputted to an image processing circuit 23 by a data read control circuit 22.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video printer such as a thermal transfer print which reads video data and print data from an image memory, outputs the video to a monitor based on the video data, and prints based on the print data. It is about.

[0002]

2. Description of the Related Art A conventional video printer of this type is shown in FIG.
9 to FIG.

FIG. 6 is a block diagram showing an example of a conventional video printer. In FIG. 6, 1 is an image memory,
Reference numeral 2 is an image processing circuit for improving image quality, 3 is a video output circuit, 4 is a print data selection circuit for extracting color signal data to be printed, and 5 is print for converting print data into transfer data to a thermal head. It is a data processing circuit.

The operation of the video print configured as described above will be described with reference to FIG. 7. Now, (n, m) is the nth in the horizontal direction (horizontal pixel number n) and the mth in the vertical direction (referred to as horizontal pixel number n). It will be described as representing the pixel data at the position of vertical pixel number m) (see FIG. 2).

When the print switch (not shown) is not operated, that is, when the video data stored in the image memory 1 is output to the monitor, and the monitor is the interlace display, the first field and the second field are displayed. The video data for monitor output is read from the image memory 1 in this order, the image processing circuit 2 performs image processing such as image quality enhancement, and then the video processing circuit 3 displays a display device such as a CRT (not shown). Video output to.

When a print switch (not shown) is turned on, the print data selection circuit 4 sequentially extracts print data from the first field video data and the second field video data, respectively, based on the vertical synchronization signal. Will be done.

That is, in the print data selection circuit 4, among the video data read from the image memory 1 with the vertical synchronizing signal as a reference, the vertical pixel numbers 1, 3, 5 are first from the first first field video data. Vertical lines corresponding to the respective horizontal pixel numbers 1 of ..., That is, vertical pixel data (1,1), (1,3), (1,
5), ... Are sequentially extracted (period A in FIG. 7), and then the vertical pixel numbers 2, 4, 6, from the second field image data.
Vertical pixel data (1,2), (1,4), (1,6) of the vertical line corresponding to each horizontal pixel number 1 of ...
Are sequentially extracted (period B in FIG. 7) to obtain print data # 1 for one vertical line corresponding to horizontal pixel number 1.
This is sent to the printer as print data, and printing for one vertical line is performed.

Next, the following first field image data,
In the same manner as above, the print data # 2 for one vertical line corresponding to the horizontal pixel number 2 is obtained from the second field image data, and subsequently, the print data #n for one vertical line corresponding to the horizontal pixel number n is sequentially obtained. , The print data #N is sequentially obtained for one vertical line corresponding to the horizontal pixel number N, and the print data for the entire one screen is obtained.

As described above, in this conventional example, the print data # 1, # 2, ..., #N for one line corresponding to the horizontal pixel numbers 1, 2, ... It means that the video data is sequentially output at the same time.

FIG. 8 is a block diagram showing another example of a conventional video printer. In FIG. 8, 11 is a dual port memory which is an image memory having two outputs.
Reference numerals 12a and 12b are image processing circuits for video data, image processing circuits for print data, 13 is a video output circuit, and 15 is a print data processing circuit.

The operation of the video print configured as above will be described with reference to FIG. The video data for monitor output is sequentially read from the dual port memory 11 in real time, and the print data is controlled to be randomly accessed, so that the video data and the print data are read in different systems, and the print data # 1 is read. , # 2, # 3, ..., #N are sequentially output simultaneously with the video data for each frame of the video data output.

[0012]

However, in the conventional video printer whose block diagram is shown in FIG. 6, the print data selection circuit 4 for extracting the print data from the video data is necessary, and therefore the circuit scale is large. There is a problem that not only the size becomes large but there is a limitation in terms of high speed printing.

Further, the conventional video printer whose block diagram is shown in FIG. 8 uses a dual port memory having two systems of outputs, which is expensive and requires complicated control. There was a problem that it would invite ups.

The present invention has been made in view of the above circumstances, and enables transfer of print data with a simple circuit configuration, and high-speed printing and high-quality printing can be realized by using an inexpensive memory. The purpose is to provide a video printer.

[0015]

In order to solve the above-mentioned problems, a video printer according to the first invention of the present application comprises an image memory, and reads out video data and print data from the image memory, In the video printer that outputs the image to the monitor based on the print data and performs the printing based on the print data, the video data output period and the print data output period are separated, and the same horizontal pixel number corresponds to the print data output period. A data read control circuit for controlling the pixel data of the vertical pixels to be continuously read from the image memory is provided.

A video printer according to a second aspect of the present invention includes an image memory, reads video data and print data from the image memory, outputs a video to a monitor based on the video data, and outputs the video based on the print data. In a video printer for printing by means of the above, the video data output period and the print data output period are divided, and pixel data of vertical pixels corresponding to the same horizontal pixel number are consecutively twice described above during the print data output period. A data read control circuit for controlling reading from the image memory is provided.

[0017]

In the video printer according to the first invention of the present application, the video data is read from the image memory during the video data output period and output to the monitor, and the vertical data corresponding to the same horizontal pixel number is read from the image memory during the print data output period. Since pixel data of pixels is continuously read out for one line and data is transferred, data processing of video data and print data can be performed by time division, and the circuit configuration can be simplified.

In the video printer according to the second invention of the present application, the video data is read from the image memory during the video data output period and is output to the monitor, and the vertical data corresponding to the same horizontal pixel number is read from the image memory during the print data output period. Pixel data of a pixel is read out continuously for one line and data is transferred, so that data can be read out in field units, cost can be reduced by using an inexpensive memory, and field interpolation can be easily performed. Therefore, high image quality and enlarged printing can be realized.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the video printer of the present invention will be described below with reference to FIGS.

As shown in FIG. 1, the video printer of the present embodiment has an image memory (RGB memory, luminance / color difference memory, etc.) 21 and an output data switching signal which becomes a pulse at a cycle of an integral multiple of the vertical synchronizing signal. Based on the memory 21
Data read control circuit 22 for controlling the time-division reading of data from the image memory 21 and an image for improving the image quality of the image data sequence and the print data sequence time-divisionally read from the image memory 21 in time series. An image processing circuit 23 for performing processing and a changeover switch 24 for selectively outputting the image-processed data in the image processing circuit 23 to the video output circuit 25 or the print data processing circuit 26 are provided.

A data transfer operation in the video printer configured as described above will be described with reference to FIGS. Assuming that pixels are stored in the image memory 21 as shown in the memory map diagram of FIG. 2, in the video printer of this embodiment, as shown in FIG. 3 and FIG. The print data for one vertical line to be printed is output in the order of horizontal pixel numbers prior to the first field video data. In FIG. 4, the horizontal pixel number n
(N = 1 to N) is shown.

That is, during the print operation period, the output data switching signal becomes low level at a cycle of an integral multiple (two times in this embodiment) of the vertical synchronizing signal, and the output data switching signal becomes low level during the period. , Print data #
As n, the pixel data (n, m) of the vertical pixel number m corresponding to the horizontal pixel number n is continuously read from the image memory 21 from m = 1 to M. When this reading is completed,
The output data switching signal becomes high level, and the first field video data and the second field video data are read from the image memory 21 in synchronization with the video output timing.

Then, the print data # 1 to the print data #N are sequentially read out in advance of the first field video data in two vertical synchronizing signal cycles, and when the printing operation is completed, the output data switching signal is automatically and constantly The level becomes high, and the transfer of print data is completed.

Video data and print data which are time-divisionally read from the image memory 21 by the data read control circuit 22 on the basis of the output data switching signal are input to the image processing circuit 23, which are time-series images of high quality. Processing is done. The image-processed data is converted into a video data string by a changeover switch 24 and a video output circuit 25.
To the print data processing circuit 25.

As described above, according to the embodiment of the video printer of the present invention, the image processing of the video data and the print data can be performed by time division, and the circuit structure can be simplified. Also, since printer data processing can be performed at the same cycle as the vertical synchronization signal,
Enables high-speed printing.

Next, another embodiment of the video printer of the present invention will be described with reference to FIG.

In the video printer of this embodiment, the image memory in the one shown in FIG. 1 according to the above embodiment is used as a field memory, and the first field video data and the second field video data are the same data. When the pixel data (n, m) of the vertical pixel number m corresponding to the horizontal pixel number n is read from the image memory as the print data prior to the first field video data, the same pixel data of m = 1 is consecutively read. Read twice,
Thereafter, similarly, 2 × M data is read in the order of m = 2, 3, ..., M. In FIG. 5, the horizontal pixel number n (n = 1
~ N).

That is, in the print operation period, the output data switching signal becomes low level at an integer multiple (here, twice) cycle of the vertical synchronizing signal, and the printing is performed during the period when the output data switching signal becomes low level. As the data #n, the pixel data (n, m) of the vertical pixel number m corresponding to the horizontal pixel number n is continuously read from the image memory twice each for m = 1 to M. When this reading is completed, the output data switching signal goes high and the first data
The field video data and the second field video data are read from the image memory in synchronization with the video output timing.

Therefore, according to another embodiment of the video printer of the present invention, in addition to the effects of the above-described embodiment,
The use of the field memory enables cost reduction, field interpolation can be easily performed in print data processing, and high image quality and enlarged printing can be realized. In the present embodiment, the field memory is used especially for cost reduction, but it is also possible to read by the field unit using the frame memory, and even in that case, the field interpolation can be easily performed. Therefore, high image quality and enlarged printing can be realized.

In the above embodiment, the print data string is read prior to the first field video data. However, the print data string is read prior to the first field video data and the second field video data, respectively. You may do it.

[0031]

Since the video printer according to the first invention of the present application is configured as described above, the video data is read from the image memory during the video data output period and is output to the monitor, and the video data is output during the print data output period. The pixel data of the vertical pixels corresponding to the same horizontal pixels are continuously read out for one line from the image memory, and the data is transferred, so that the data processing of the video data and the print data can be performed by time division, and the circuit configuration can be simplified. can do.

A video printer according to a second aspect of the present invention reads out video data from an image memory during a video data output period and outputs it to a monitor, and also outputs vertical pixels corresponding to the same horizontal pixel from the image memory during a print data output period. Since the pixel data of 1 is continuously read twice for one line and the data is transferred, the data can be read in field units, the cost can be reduced by using an inexpensive memory, and the field interpolation can be easily performed. It is possible to realize high image quality and enlarged printing.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a video printer of the present invention.

FIG. 2 is a memory map diagram showing a storage state of pixels in an image memory in one embodiment of the video printer of the present invention.

FIG. 3 is a timing chart showing output data in one embodiment of the video printer of the present invention.

FIG. 4 is an enlarged explanatory view of a main part in FIG.

FIG. 5 is a timing chart showing output data in another embodiment of the video printer of the present invention.

FIG. 6 is a block diagram showing an example of a conventional video printer.

FIG. 7 is a timing chart showing output data in an example of a conventional video printer.

FIG. 8 is a block diagram showing another example of a conventional video printer.

FIG. 9 is a timing chart showing output data in another example of the conventional video printer.

[Explanation of symbols]

 21 image memory 22 data read control circuit 23 image processing circuit 24 changeover switch 25 video output circuit 26 print data processing circuit

Claims (2)

[Claims] 1. A video printer comprising an image memory, wherein video data and print data are read from the image memory, video is output to a monitor based on the video data, and printing is performed based on the print data. A data read control circuit is provided for dividing the data output period from the print data output period, and controlling the pixel data of the vertical pixels corresponding to the same horizontal pixel to be continuously read from the image memory during the print data output period. A video printer characterized by that. 2. A video printer comprising an image memory, wherein video data and print data are read from the image memory, video is output to a monitor based on the video data, and printing is performed based on the print data. A data read control for dividing the data output period from the print data output period, and controlling the pixel data of the vertical pixels corresponding to the same horizontal pixel to be continuously read twice from the image memory during the print data output period. A video printer provided with a circuit.