JPS60109377A - Processing system of picture signal - Google Patents

Abstract

PURPOSE:To shorten the required time of scanning by recording due to a heating value of black coloring in accordance with a received black picture signal, and carrying out red recording on the black coloring due to a heating value of red coloring in accordance with a red picture signal. CONSTITUTION:A picture signal (c) from an image sensor based on green light GL is stored in a memory and transmitted as a black picture signal B, and a picture signal (e) from a sensor based on red light RL is transmitted as a red picture signal R after the signal (e) is synthesized by contents in the memory. After a receiving side has carried out black recording due to a heating value of black coloring in accordance with the initial black picture signal B, the side carries out red recording on the black one due to a heat value of red coloring in accordance with the red picture signal R.

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention uses thermal recording paper that changes color from white to black and then from black to red as the amount of heat applied increases. The present invention relates to an image signal processing method applied to a facsimile machine that performs transmission and recording.

[Prior art]

FIG. 1 is a timing chart of a conventional example showing the operating status of the transmitting side. During one period of the main scanning period indicated by the interval of the main scanning pulse 1:a), as shown in the scanning light (b), The scanning surface is alternately irradiated with green light GL and red light RL, and through the image signal (c), scanning is performed once for green light GL and twice for red light RL. is performed on the image sensor, and the memory access situation is shown in (d).
Write the image signal from the image sensor based on L WT
The red light RL is stored in the memory and the red light is scanned for the second time.
image signal from the image sensor based on and readout RD
After combining the contents of the memory which has been taken out, it is transmitted as a black image signal B (,), and the image of the image sensor 75- etc. is generated based on the red light RL from the third scan. The signal and the similarly extracted memory contents are combined and transmitted as both red signals R.

Note that the white of the scanning surface corresponding to the green light GL and the red light RL,
The reflectance for black and red is as shown in the following table, and the transmitted image signals B and R are determined according to the image signal from the image sensor according to the reflectance.

However, in the above method, as is clear from FIG. is not transmitted continuously,
This causes drawbacks such as a reduction in transmission speed.

[Summary of the invention]

The purpose of the present invention is to fundamentally eliminate the drawbacks of the conventional method. On the transmitting side, first, an image signal based on light of a wavelength with a low reflectance for black and red is stored in a memory, and a black image signal is stored in a memory. Next, an image signal based on light with a wavelength that has a low reflectance for black and a high reflectance for red is combined with the contents of the memory, and is sent as a red image signal. The image sensor is scanned only twice during each period, and the image signal is continuously transmitted, while the receiving side records the amount of heat generated by thermal coloring according to the received black image signal. , Next, in response to the received red image signal, red is recorded on top of the black that was printed the first time using the amount of heat generated by the red color.
This provides an image signal processing method.

〔Example〕

The present invention will be described in detail below with reference to FIG. 2 showing an embodiment.

FIG. 2 is a timing chart showing the operating status of the transmitting side. During one period of the main scanning period indicated by the interruption of the main scanning period pulse (,), the scanning light (b) is transmitted to the green light GL.
At the same time, the image sensor is scanned twice, and the image signal (,) is generated twice in response to this, and the memory access status ( d) and transmission (,) as shown in
The image signal (C) from the image sensor based on the green light GL from the first scan is stored in the memory by the writing WT, and is transmitted as a black image signal B by the transmission (e), and then is transmitted as a black image signal B by the transmission (e). The image signal (C) from the image sensor based on the red light RL in the second scan is read out RD
It is combined with the extracted memory contents and sent (
e) It is transmitted as a red image signal R, and this is repeated in accordance with the generation of the main scanning period pulse (&).

Therefore, the image signals B and H are transmitted continuously, and the image sensor scans only twice during one cycle, making it possible to shorten the main scanning period, thereby reducing the time required for scanning. The transmission speed of the image signals B and H is increased.

FIG. 3 is a block diagram showing an image signal processing circuit on the transmitting side. The output of the image sensor Is, which is scanning based on the clock pulse CLK, is applied to the AND gate G1, the memory MM, and the synthesis circuit SNS. Image sensor Is based on green light GL from the first scan
The image signal from the clock pulse CLK and the image signal shown in FIG.
The control signal generated at the same timing as d) is stored in the memory MM in response to the control signal /R, and the green gate signal GSo generated in response to the lighting of the green light source is ANDed (Gl).
1H〃 (high level), same game) Gl is turned on, so same game) Gl and OR game) Gs
The black image signal B is sent to the receiving side via the transmitting circuit.

Next, when the red light source lights up, the red gate signal GSa becomes NH and the AND gate G2 is turned on, so that the image sensor Is is scanned for the second time.
The image signal based on the red light RL from
The image signal based on L is synthesized by the synthesis circuit SNS according to the control signal CS, and the AND gate G2 and the OR
The signal is sent to the output OUT via the gate G3, and is sent as a red image signal R as in the previous case.

On the other hand, on the receiving side, in synchronization with the sending side, a signal with a short pulse width that is the amount of heat for black coloring is applied to the recording head in accordance with the first black image signal B in a predetermined order. After recording black, in response to the red image signal R received next, a signal with a long pulse width that is the amount of heat for red coloring is similarly applied, and only the necessary pixels are recorded on the black that was printed the first time. Record the red color.

Note that the synthesis circuit SNS in FIG. 3 performs synthesis based on the logical conditions shown in the table above, and if the scanning surface is only black, the red image signal B is not sent out.

Therefore, if the scanning surface is only black, only black recording will be performed on the receiving side, and if the scanning surface is red, the black recording will be updated to red recording on the receiving side.
Recording is performed in the same manner as in the past, using short-cycle scanning and high-speed transmission.

In addition, in order to realize the operation shown in Figure 2 and the operation on the receiving side, it is only necessary to slightly change the conventional circuit configuration.
The composite circuit SNS shown in the figure may be used by combining various gates according to the logic conditions shown in the table above.

Then, connect the AND gates Gl and G2 in Figure 3 to NAND.
It may be replaced with a gate, an inhibit gate, a switch circuit, etc., or a NAND gate, a mixing circuit, etc. may be used in place of the OR gate (OR gate) G3, and various modifications are possible.

Although the above embodiments have been explained using green light and red light, the present invention is not limited to these lights, and instead of green light, light with a wavelength having a small reflectance for black and red can be used. Alternatively, instead of red light, light having a wavelength that has a low reflectance for black and a high reflectance for red may be used.

〔Effect of the invention〕

As is clear from the above explanation, according to the present invention, the number of scans of the image sensor is reduced, the time required for scanning is reduced, and the transmission image signal is continuously transmitted. This provides a significant effect in facsimile machines that transmit and record in two colors, black and red.

[Brief explanation of the drawing]

Fig. 1 is a timing chart of a conventional example showing the operating status of the transmitting side, Fig. 2 and subsequent figures show examples of the present invention, Fig. 2 is a timing chart showing the operating status of the transmitting side, and Fig. 3 is a timing chart of the transmitting side. FIG. 2 is a block diagram showing an image signal processing circuit of FIG. IS...Image sensor, MM...Fist memory, S
NS ・・・@Synthesis circuit, Gl, G2@11@AND gate, G3 ・ ・ ・ ・OR gate, GSa ・・
Fist/green gate signal, GSR-...red gate signal. Continuation of page 1 @ Inventor Minoru Kazusaki 1-235 Hata, Takeshi, Yokosuka City Yokosuka Telecommunications Research Institute, Nippon Telegraph and Telephone Public Corporation

Claims (1)

[Claims] In a facsimile machine that transmits and records in two colors, black and red, using heat-sensitive recording paper that changes color from white to black and from black to red as the amount of heat applied increases, on the sending side, one cycle of the main scanning cycle In the first scan, an image signal based on light with a wavelength with a low reflectance for black and red is stored in the memory and transmitted as a black image signal, and in the next scan, the image signal based on light with a low reflectance for black is stored in the memory. The content of the memory is combined with an image signal based on a wavelength of light that has a small red reflectance and a high reflectance for red, and is then transmitted as a red image signal. Recording is performed according to the amount of heat of color development, and then red is recorded on top of the black on which the 11th recording was performed according to the amount of heat of red color development in response to the received red image signal. Image signal processing method.