JPS60143061A - Reading and recording method of multi-color picture - Google Patents

Abstract

PURPOSE:To reduce the circuit scale and the transmission time by selecting one piece of color information among plural different pieces of color information and recording the information based on the selected color information. CONSTITUTION:A picture an original face 1 is collected by a lens 2 and split into three by two half mirrors 3a, 3b. An output of photoelectric converters 5a- 5c is inputted to a level deciding circuits 6a-6c and the circuits 6a-6c output logical ''1'' when the input is lower than a fixed potential and outputs logical ''0'' when the input is higher. A logical circuit 8 consists of OR gates 9a, 9b, an NAND gate 10, inverters 11a, 11b and AND gates 12a-12c and selects any one color of color information with priority when >=2 colors of color information among three colors (black, blue, red) except a background color is detected from the original face 1.

Description

[Detailed description of the invention] [Technical field of invention] The present invention relates to (1) a method for reading and recording multicolor images;

[Technical background of the invention and its problems]

Most originals, such as ordinary facsimile originals, are in two colors, black and white, and do not require halftones. However, recently there has been an increasing demand for multicolor recording, such as that seen in multicolor facsimiles, when dealing with graphs.

Multicolor facsimile is a method in which color information of two or more colors, excluding the background color (usually white) on the document surface, is transmitted and recorded on the receiving side. Conventionally, multicolor facsimile transmission devices have adopted a method in which the color information read from the document surface is sent several times as often as in a normal two-color facsimile. For example, when sending color information for a total of 4 colors (black, evening, and red) outside the white background, it takes three times as long as a two-color facsimile because the color information for black, blue, and red is sent separately. Transmission will be performed by applying As described above, the conventional multicolor facsimile transmitting apparatus has problems in that the circuit size is large because it constantly handles all color information, and that it takes a long time to transmit the color information in code.

[Purpose of the invention]

The present invention has been made in view of these points, and its purpose is to provide a method for reading and recording multicolor images that can reduce the circuit scale and transmission time in multicolor facsimiles and the like. .

[Summary of the invention]

In general, in most documents such as facsimile documents, there is no need to mix gray colors that transmit halftone color information, such as graphs, even if they are multicolor documents. The present invention has been made in view of the above circumstances, and when reading and recording a multicolor image from the document surface, one of the plurality of different color information detected from the document surface by the plurality of photoelectric conversion means. Color information is selected and recording is performed based on the selected color information.

〔Effect of the invention〕

According to the present invention, when sending three colors, black, red, and blue, in addition to the white background in conventional multicolor facsimiles, mixing of colors is allowed, and information on whether to send or not to send each color is independent. 23 = 8 types of states had to be transmitted, but since mixing of colors is not allowed and only one color is always transmitted, only 4 types of states need to be transmitted. . For example, when information from the document surface is sampled pixel by pixel and color information is transmitted as a code, the former conventional method requires sending a 3-bit code per pixel, but the latter method of the present invention requires that a 3-bit code be sent per pixel. For example, 92 per pixel
It is sufficient to send the bit code, which reduces the transmission time to two-thirds and greatly reduces the circuit scale.

[Embodiments of the invention]

FIG. 1 is a configuration diagram of a transmitting side showing an embodiment of the present invention applied to a facsimile machine, and FIG. 2 is a waveform diagram of each part thereof. l is the side of the document to be sent, the background color (usually white)
2 or more colors, in this example black, red, and blue
It shall include color. The image on this document surface is from lens 2.
The light is focused and divided into three parts by two half mirrors 3a + Jb. The light transmitted through the first half mirror 3a enters the first photoelectric converter 5a.

The light reflected from the first half mirror 3a enters the second half mirror 3b, and the light reflected from the second half mirror 3b passes through the blue complementary color filter 4a to the second photoelectric converter 5.
The light that has passed through the second half-mi y-3b and the second half-mi y-3b enters the third photoelectric converter 5c via the red complementary color filter 4b. First to third photoelectric converters 5a to 5cl
Both output high potential signals when the amount of incident light is large, and low potential signals when the amount of incident light is small, and the respective output waveforms are shown in Figure 2 (
, ) to (c).

Outputs (,) to (c) of the first to third photoelectric converters 5a to 5c
) are input to the first to third level determination circuits 68 to 6C. Each of the level determination circuits 6a to 6c outputs a logic level signal of 111++ if the input voltage is lower than a certain potential, and °O'' if it is higher, and the respective output waveforms are shown in FIGS. 2(d) to (f). That is, when the output of the first light weight converter 5a that detects all the colors of light from the document surface 1 is lower than a certain potential, the first level determination circuit 6IL detects the original γ! It is determined that color information of black, dark, or red is detected from surface l, and a logic level II I N is output.

Further, when the output of the second photoelectric converter 5b that detects evening complementary color light is lower than a certain potential, the second level determination circuit 6b determines that blue color information has been detected from the document surface 1, and performs a logic Output level niy+. Furthermore, the third level determination circuit 6c includes a third photoelectric converter 5c that detects light of a complementary color to red.
If the output is lower than a certain level, it is determined that red color information has been detected from the document surface l, and a logic level "1" is output.

On the other hand, 7 is a level comparison circuit that compares the outputs (b) and (c) of the second and third photoelectric converters 5b and 5c.
) outputs a logic level signal of 1" if the potential is lower, and 0" if it is higher. The output waveform of this level comparison circuit 7 is shown in FIG. 2(g).

Outputs (d) to (g) of these level determination circuits 6a to 6C and level comparison circuit 7 are input to logic circuit 8. This logic circuit 8 is a black color excluding the background color from the original surface 1.
When color information for two or more of the three colors W and red is detected, color information for one of the three colors is selected preferentially, and 9! L.

9b is OR dart, JO is NAND dart, 11a.

11b is an inverter, and 12a to 12C are AND darts. The inputs (d) to (g) of this logic circuit 8 are A.

If we put outputs (h) to (j) as B, C, and D and put them as X, Y, and Z, the logical formula becomes as follows.

X=A・(B-1-C) =C・(B-D) As can be seen from this logical formula, when at least one of B and C is °°1'', X is definitely not 1#. and if only B is pa1n, then Y-″1#tez=”o″′,
When only C is '°1', Y = '0' and z = 'i'
becomes. Further, when both B and C are llt'', according to the comparison result of the level comparison circuit 7, if D = ``l'', Y
= “1” fZ = “0”, D = 11011
Then, y = “o” and z = “1”.

Here, x = “1” means that black information is selected Y-
11111 means that blue information is selected and z = ”
1'' respectively means that red information is selected and transmitted.

That is, in the above configuration, since there is no filter in front of the first photoelectric converter 5a, even when blue or red is detected, the first level determination circuit 6IL is processed in the same manner as when black is detected. A, which is the output (d), becomes 1". However, in such a case, X = "0" and transmission of black information is prohibited, and Y = "1" or z =
"i" and blue information or red information is transmitted.Furthermore, when both evening and red information are detected at the same time, the second and third level determination circuits 6b.

Both B and C, which are the outputs (, ) and (f) of 6c, are Ilt'', but the level comparison circuit 7 determines which one is more prominently detected, and Y is determined according to the result.

Since only one of Z becomes II l #I, only one of the blue information and the red information that is significantly detected is selected and transmitted. This situation is also clear from FIG. 2 (h) to (j) showing the output waveforms (X, Y, Z) of the logic circuit 8.

In fact, as shown in FIG. 1, the output of the logic circuit 8 is
It is convenient to perform code conversion in the two OR groups 13a and 13b before transmitting. In this way, the black information is output from the outputs of the OR groups 13m, 13b as shown in FIG.
1, Y = IIQ", Z = "O") is 1""1
″, if blue information is selected (X=°°0”, Y=″1
”, Z=“0”), °゛1”NO#, if red information is selected (X-“0”, Y=“0”.

2="1"), '0''"t 1 n, only white without color information (x = "o", y = "o',, z
= ``o') If ``KU''0#''0'' combination 2
The sign of the bit is obtained.

Therefore, in the case of code transmission, OR'r' −) 13
a.

The output of 13b may be transmitted as is, or in the case of analog multi-value transmission, it may be transmitted after converting it into a 4-level analog 'frj signal using a 1)/A converter.

As described above, only one color information is always selected and transmitted, and recording is performed on the receiving side based on that color information.

According to the present invention, when recording is performed on the receiving side, each pixel is composed of a single color, and mixed colors and halftone colors are not displayed. However, in general, documents for facsimile etc. Considering that most of the things that are colored do not require a mixture of colors or intermediate colors,
There is no practical problem.

Additionally, in the actual case, if color information other than black (excluding the background color) was detected from the document surface, transmission of the black information was prohibited and the color information other than black was transmitted. Therefore, faithful transmission is possible without the fear that parts that should be blue or red will become black on the receiving side.

In addition, in the present invention, the logic of preferentially selecting color information of one color from two or more color information excluding the background color detected simultaneously from the document surface is not limited to the above embodiments; for example, You can compare the color information levels of all colors including black and select the highest color information, or you can prioritize each color in advance and choose the highest priority among the color information detected at the same time. may be selected. Furthermore, it goes without saying that the present invention can also be applied to the case where color information of four or more colors other than the background color is handled.

Figure 1 is a configuration diagram of a facsimile transmitting device for explaining a method for reading and recording a multicolor image according to an embodiment of the present invention, and Figure 2 is a diagram showing its configuration. It is a waveform diagram of each part showing operation.

1... Original surface, 4a, 4b... Filter, 51L~
5c...Photoelectric converter, 68-6C...Level judgment circuit, 7...Level comparison circuit, 8...Logic circuit.

Applicant's representative Zuf Burial Officer Suzue Takehiko Figure 1 Figure 2 ! )

Claims (1)

[Claims] When reading and recording a multicolor image from the document surface, one color information is selected from among a plurality of different color information detected from the document surface by a plurality of photoelectric conversion means, and a multicolor image is recorded based on the selected color information. A method for reading and recording a multicolor image, characterized in that recording is performed using a multicolor image.