JPH0370384A - Color image forming device - Google Patents

Abstract

PURPOSE:To form a still image which provides an intended light-shade feeling and has intended color balance by printing out the same image as a color image projected on a color monitor by a printer part. CONSTITUTION:A gamma correcting means 5 multiplies a still image signal by the reciprocal of a gamma value for a color image receiver 12 and a color converting means 1 converts the image signal obtained by the gamma correcting means 5 into a color signal; and the color signal from the color converting means 1 is stored in a storage means 11 and the image is projected on the color receiver 12 according to color information read out of the storage means 11. Then the color information read out of the storage means 11 is corrected by a gamma correcting means 5, a color density converting means 6 converts the gamma-corrected color information into density information, and the image is recorded by an image recording means 8 according to the obtained color density. Consequently, the image which provides the intended light-shade feeling and has the intended color balance can be formed.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention digitizes still image signals from still video cameras, t' (SV) cameras, SV recording media, etc., imports them into memory, and processes the signals to create color images. The present invention relates to a color image forming apparatus configured to form a color image.

[Prior Art] A conventional color image forming apparatus, for example, a color copying apparatus, converts an Sv flaw signal into a digital signal, stores the digital signal in a memory, processes the signal read out from the memory, and processes the processed signal. Color printing was now possible based on the digital signals received.

[Problems to be Solved by the Invention] However, when an image taken with an Sv camera is printed in color, the reproduced image may differ from the scene and impression when it was taken, especially in terms of clarity and color balance. Ta.

SUMMARY OF THE INVENTION An object of the present invention is to provide a color image forming apparatus that can solve the above-mentioned problems and form a still image having intended contrast and color balance.

[Means for Solving the Problem] In order to achieve such an object, the present invention provides a correction means for raising a still image signal to the reciprocal power of a gamma value for a color receiver, and an image signal obtained by the correction means. color conversion means for converting into a color signal; storage means for storing the color signal from the color conversion means; and image projection for projecting an image on the color receiver based on the color information read from the storage means. gamma correction means for gamma-correcting the color information read out from the storage means; color density conversion means for converting the color information gamma-corrected by the gamma correction means into density information; The present invention is characterized by comprising an image recording means for recording an image based on the color density obtained by the color density conversion means.

The present invention also provides a correction means for raising a still image signal to the reciprocal power of a gamma value for a color receiver, a color conversion means for converting the image signal obtained by the correction means into a color signal, and a color conversion means for converting the image signal obtained by the correction means into a color signal. a storage means for storing a color signal; and an image projection means for projecting an image on the color receiver based on the color information read from the storage means, and the color read from the storage means. gamma correction means for gamma-correcting information; color density conversion means for converting color information gamma-corrected by the gamma correction means into density information; and recording an image based on the color density obtained by the color density conversion means. The apparatus is characterized in that it comprises an image recording means, and a changing means for changing the color information stored in the storage means.

[Function] In the present invention, the still image signal is raised to the reciprocal power of the gamma value for the color receiver by the correction means, the image signal obtained by the correction means is converted into a color signal by the color conversion means, and the color conversion means converts the image signal obtained by the correction means into a color signal. storing the color signal in a storage means, projecting an image on the color receiver by the image projection means based on the color information read out from the storage means, and gamma correcting the color information read out from the storage means. The color information corrected by the gamma correction means is converted into density information by the color density conversion means, and an image is recorded by the image recording means based on the color density obtained by the color density conversion means.

Further, in the present invention, the still image signal is raised to the reciprocal power of the gamma value for a color receiver by the correction means, the image signal obtained by the correction means is converted into a color signal by the color conversion means, and the color from the color conversion means is storing the signal in a storage means, projecting an image on the color receiver by the image projection means based on the color information read from the storage means, and using the gamma correction means to project the color information read from the storage means. Gamma correction is performed, the color information gamma corrected by the gamma correction means is converted into density information by the color density conversion means, and an image is recorded by the image recording means based on the color density obtained by the color density conversion means, and is stored. The color information stored in the means is changed by the changing means.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a first embodiment of the invention.

In the figure, 1 is a color conversion section as a color conversion means, and SV
This converts the double signal luminance color difference signal into R, G, and B color signals. 2 is an A/D converter (A/D) that converts the analog R, G, and B color signals from the color converter 1 into digital R, G
, B color signal. Reference numeral 3 denotes a memory serving as a storage means for storing digital R, G, and B color signals.

IO is a ROM in which a look-up table (LOT) is stored. 14 is an operation unit for selecting LIFT stored in ROM 1G. 9 is CPU
Then, the LtlT selected by the operation unit 14 is stored in the RAM 4.
．． 11. Operation unit 14, CPII
9. RAM 4, 114: Consists of changing means. 12 is a color monitor, L stored in RAM 11
An image is displayed based on digital R, G, and B color signals converted based on IIT.

Reference numeral 5 denotes a gamma correction section as a gamma correction means, which performs degamma to the power of 2.2 based on the LOT stored in the RAM 4. Reference numeral 6 denotes a logarithmic conversion section as a color density conversion means, which converts the R, G, and 11 signals γ-corrected by the γ' correction section 5 into Y, M signals. A masking section 7 removes color turbidity from the density obtained by the logarithmic conversion section 6.

Reference numeral 8 denotes a printer section as an image recording means, which performs color printing based on signals from the masking section 7.

Since the color image forming apparatus of this embodiment is configured as described above, the printer section 8 prints out a color image that is the same as the color image displayed on the color monitor 12.

That is, the Sv signal I' can be approximated by the relational expression 1' = 10.4B, where I is a linear signal with respect to the light amount, and the straight line shown in Fig. 2 is However, it can be approximated by the relational expression a: slope). In addition, color picture tubes are γ-
2,2, so if the amount of light emitted from the phosphor of the color monitor 12 is (■), it can be approximated by the relational expression 1,=I''22.Therefore, 1, .
The relationship of I can be expressed as 1,=a'''1.

On the other hand, since the γ correction unit 5 is γ-2,2, the γ correction unit 5
If the output signal of is Iyo, it can be expressed as T, = 1''22 = 82.2■.

To create a desirable image, the user looks at the color monitor and selects R, G, and B independently from the tables shown in Figure 2.
Select an appropriate table from
The CPU sets the table to RAM 11 and displays the image on the color monitor, and the selected table is stored in RAM 4.
Also set.

FIG. 3 shows a second embodiment of the invention.

This embodiment is different from the first embodiment in the configuration of the gamma correction means. That is, in the first embodiment, the γ correction unit 5 performs the γ correction, but in this embodiment, the RAM storing the table shown in the first figure
4 to perform γ correction. However, RAM
A table shown in the second figure is stored in 11. This has the advantage that digital loss is reduced.

FIG. 5 shows a third embodiment of the invention.

This embodiment differs from the first embodiment in gamma correction means. That is, in the first embodiment, the γ correction unit 5 performs γ correction, but in this embodiment, the RAM 4
, a γ correction unit 5, and a logarithmic conversion unit 6. This has the advantage of reducing digital loss.

[Effects of the Invention] As described above, according to the present invention, since it is configured as described above, it is possible to form an image having intended brightness and color balance.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention, FIG. 2 is a diagram showing an example of the contents of a table used in the first embodiment of the present invention, and FIG. 3 is a block diagram showing a second embodiment of the present invention. 4 is a diagram showing an example of the contents of a table used in the second embodiment of the present invention, and FIG. 5 is a block diagram showing the third embodiment of the present invention. 4...RAM 5...γ correction section, 6...logarithmic conversion section, 7...masking section, 8...printer section, 9...CPU, 10...rlOM. 11...RAM. 12...Color monitor. 1...Color conversion unit, 2...^10 converter, 3...Memory, Fig. 2, Fig. 4, Fig. 3

Claims (1)

[Scope of Claims] 1) correction means for raising a still image signal to the reciprocal power of a gamma value for a color receiver; color conversion means for converting the image signal obtained by the correction means into a color signal; and the color conversion means. storage means for storing color signals from the storage means; and image projection means for projecting an image on the color receiver based on the color information read from the storage means; gamma correction means for gamma-correcting the color information obtained by the gamma correction means; color density conversion means for converting the color information gamma-corrected by the gamma correction means into density information; 1. A color image forming apparatus comprising: an image recording means for recording. 2) A color image forming apparatus according to claim 1, further comprising changing means for changing the color information stored in said storage means.