Patent Publication Number: US-6343144-B2

Title: Method and apparatus for image processing, and storage medium

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an image processing apparatus and an image processing method in which image information is read from a recording medium and image processing is suitably performed in accordance with the read image information. The invention also pertains to a storage medium in which the above method is stored. 
     2. Related Background Art 
     Hitherto, the following type of film scanner is known: image information is read from a developed negative or positive film by the scanner and is output to, for example, a printer. The above type of film scanner has an image processing section for processing the read image information. Before the image processing section performs image processing on the read image, it is necessary to check the characteristics of the image. This further requires that an image should be first read from a film and then analyzed. 
     In order to overcome the above drawback, an image pick-up apparatus is known which is able to record on the surface of the film various types of information, such as photographic conditions, concerning a photographed picture. By using a film in which a picture (image) is recorded by the above type of image pick-up apparatus, the characteristics of the picture are obtained merely by reading information, such as photographic conditions, recorded on the film without needing to read the picture from the film and extracting its characteristics. 
     SUMMARY OF THE INVENTION 
     Accordingly, in view of the above background, it is an object of the present invention to efficiently perform color-processing of an image recorded on a recording medium by using focus information concerning the focus of the image when the image is taken, the image and the focus information being recorded on the recording medium by different methods. 
     It is another object of the present invention to efficiently perform filtering-processing on an image recorded on a recording medium by using focus information concerning the focus of the image when the image is taken, the image and the focus information being recorded on the recording medium by different methods. 
     In order to achieve the above objects, according to one aspect of the present invention, there is provided an image processing apparatus comprising: first reading means for reading an image recorded on a recording medium; second reading means for reading focus information concerning the focus of the image when the image is taken, the image and the focus information being recorded on the recording medium by using different methods; and color-processing means for color-processing the image read by the first reading means in accordance with the focus information read by the second reading means. 
     According to another aspect of the present invention, there is provided an image processing method comprising: a first reading step of reading an image recorded on a recording medium; a second reading step of reading focus information concerning the focus of the image when the image is taken, the image and the focus information being recorded on the recording medium by using different methods; and a color-processing step of color-processing the image read in the first reading step in accordance with the focus information read in the second reading step. 
     According to still another aspect of the present invention, there is provided a storage medium in which an image processing program is stored in such a manner that the program is readable by a computer, the program comprising: a first reading step of reading an image recorded on a recording medium; a second reading step of reading focus information concerning the focus of the image when the image is taken, the image and the focus information being recorded on the recording medium by using different methods; and a color-processing step of color-processing the image read in the first reading step in accordance with the focus information read in the second reading step. 
     According to a further aspect of the present invention, there is provided an image processing apparatus comprising: first reading means for reading an image recorded on a recording medium; second reading means for reading focus information concerning the focus of the image when the image is taken, the image and the focus information being recorded on the recording medium by using different methods; and filter-processing means for filter-processing the image read by the first reading means in accordance with the focus information read by the second reading means. 
     According to a further aspect of the present invention, there is provided an image processing method comprising: a first reading step of reading an image recorded on a recording medium; a second reading step of reading focus information concerning the focus of the image when the image is taken, the image and the focus information being recorded on the recording medium by using different methods; and a filtering step of filtering the image read in the first reading step in accordance with the focus information read in the second reading step. 
     According to a yet further aspect of the present invention, there is provided a storage medium in which an image processing program is stored in such a manner that said program is readable by a computer, the program comprising: a first reading step of reading an image recorded on a recording medium; a second reading step of reading focus information concerning the focus of the image when the image is taken, the image and the focus information being recorded on the recording medium by using different methods; and a filtering step of filtering the image read in the first reading step in accordance with the focus information read in the second reading step. 
     Further objects, features and advantages of the present invention will become apparent from the following description of the preferred embodiments with reference to the attached drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic view illustrating a configuration of an image processing apparatus according to an embodiment of the present invention; 
     FIG. 2 is a schematic view illustrating a film scanner shown in FIG. 1; 
     FIG. 3 is a timing chart illustrating the control timing provided to perform density reproduction in the printer shown in FIG. 1; 
     FIG. 4 is a schematic diagram illustrating the flow of an image signal in the image signal processing unit of the image scanner shown in FIG. 1; 
     FIG. 5 illustrates the under-color processing section shown in FIG. 4; 
     FIG. 6 is a diagram illustrating a technique of obtaining the under-color level from a density histogram; 
     FIG. 7 is a timing chart illustrating the timing provided for the control signal used in the image signal processing unit shown in FIG. 4; 
     FIG. 8 illustrates the relationship between the input data and the output data in the look up table (LUT) shown in FIG. 4; and 
     FIG. 9 is a flow chart illustrating the process used in the image processing unit shown in FIG.  4 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A preferred embodiment of the present invention is described in detail below with reference to the accompanying drawings. 
     FIG. 1 is a schematic sectional view of an image processing apparatus according to a preferred embodiment of the present invention. In FIG. 1, the image processing apparatus has an image scanner  201  and a printer  200 . The image scanner  201  reads a document or a film and converts an image signal corresponding to the read image to a digital signal. The printer  200  prints in full color on a sheet of paper an image corresponding to the image signal digitized by the scanner  201 . 
     The configuration of the image scanner  201  is as follows. 
     In order to read an image of an original document  204  placed on an original-document glass (platen)  203 , the document  204  held on the glass  203  by a document press plate  202  is exposed to light from a halogen lamp  205 . The light reflected by the document  204  is transmitted to mirrors  206  and  207 , and an image is formed on a three-line sensor (hereinafter referred to as “the CCD”)  210  by a lens unit  208 . The lens unit  208  is provided with an infrared-blocking filter  231 . 
     The CCD  210  performs color separation on the light reflected from the document  204  and extracts color elements, such as red (R), green (G), and blue (B), of full color information and sends them to an image signal processing unit  209 . The sensor arrays of the CCD  210  for reading the color elements are each formed of 5000 pixels. In this manner, the width (297 mm) of an A3-size document, which is the maximum size placable on the document glass  203 , can be read with a 400-dpi resolution. 
     The halogen lamp  205  and the mirror  206  are moved at a velocity V, while the mirror  207  is shifted at a velocity 1/2 V, in the directions indicated by the arrows shown in FIG.  1 . In this fashion, the halogen lamp  205  and the mirrors  206  and  207  are mechanically moved in the perpendicular direction (hereinafter referred to as “the sub-scanning direction”) in relation to the CCD  210  in the electrical scanning direction (hereinafter referred to as “the main scanning direction), thereby scanning the overall surface of the document  204 . 
     A standard white plate  211  is used for obtaining corrected data for the read data output from the R, G and B sensors  210 - 1 ,  210 - 2  and  210 - 3  of the CCD  210 . The standard white plate  211  exhibits substantially uniform reflection characteristics in response to visible light. In this embodiment, the image data output from the R, G and B sensors  210 - 1  through  210 - 3  is corrected by utilizing the intensity of the light reflected by the white plate  211 . 
     The operation of reading an image signal and magnetic information from the film  4  with a film scanner  227  is described below. 
     FIG. 2 is an exploded view illustrating the internal configuration of the film scanner  227 . The film  4  used in this embodiment has an optical recording portion for optically recording a photographic picture and a magnetic recording portion for magnetically recording various photographic conditions (for example, auxiliary information concerning the focal length, the zoom magnification, and the aperture) when the picture is taken. 
     Referring to FIG. 2, a magnetic head  1  serves as reading means for reading the above magnetic recording (photographic data) portion. The film scanner  227  includes a hold pad  2  for holding the magnetic head  1 , a film cartridge  3 , a film  4 , a spool  5  for winding the film  4 , and an illuminating device  6  for a scanner  7 . The scanner  7  has R, G and B-color line sensors and reads the picture recorded on the film  4  based on the light passing through the film  4 . The film  4  is fed to relatively move the scanner  7  in the sub-scanning direction. A feeding gear unit  8  is used for feeding the film  4  from the film cartridge  3 . A fork  10  is employed for driving the spool  5  to wind the film  4 . The film scanner  227  further includes a feeding gear unit  9  and a spool driving gear unit  11 . A feeding motor  12  is connected to both the feeding gear unit  9  and the spool driving gear unit  11 . 
     In the film scanner  227  constructed as described above, the feeding motor  12  is operated to feed the film  4 , and simultaneously, the photographic data magnetically recorded on the film  4  is read by the magnetic head  1 . At this time, the scanner  7  also reads the image (developed image) recorded on the film  4 . 
     A description is given below of the image signal processing unit  209  for receiving the image signal from the image scanner  201  or the film scanner  227 . 
     Referring back to FIG. 1, the image signal processing unit  209  switches between an image signal obtained by reading the document  204  placed on the document glass  203  with the image scanner  201  and an image signal read from the film  4  with the film scanner  227 . The selected image signal is then input and electrically processed in the image signal processing unit  209  so as to be separated into the respective color elements, such as magenta (M), cyan (C), yellow (Y), and black (Bk). The separated color elements are then output to the printer  200 . When an image is printed from the image scanner  201 , data concerning one of the color elements, M, C, Y and Bk, is output to the printer  200  by scanning a document one time (plane-sequential image formation), and the entire image contained in one sheet is printed in full color by scanning the document four times. 
     In the-printer  200 , a semiconductor laser  213  is modulated by a laser driver  212  based on the image signals of the respective colors M, C, Y, and Bk which have been processed and sent from the image signal processing unit  209 . Laser light output from the modulated semiconductor laser  213  reaches and scans a photosensitive drum  217  via a polygonal mirror  214 , a f-θ lens  215 , and a mirror  216 . Thus, an electrostatic latent image corresponding to the input image signals is formed on the photosensitive drum  217 . 
     A developer device is formed of a magenta developer unit  219 , a cyan developer unit  220 , a yellow developer unit  221 , and a black developer unit  222 . The four developer units  219  through  222  sequentially contact the photosensitive drum  217  to develop the latent image having the respective colors M, C, Y and Bk formed on the photosensitive drum  217  with the corresponding colors of toner. A transfer drum  223  takes up and winds a sheet of paper fed from a sheet cassette  224  or  225  so as to transfer the toner image developed on the photosensitive drum  217  to the sheet, thereby forming a color image on the sheet. 
     After the toner images having the respective four colors M, C, Y and Bk are sequentially transferred to the sheet, the sheet passes through a fixing unit  226  and is then discharged to the exterior of the image processing apparatus. 
     An explanation is given below of a density reproducing method used in the printer  200  of the image processing apparatus according to an embodiment of the present invention. 
     In the printer  200  of this embodiment, in order to precisely reproduce image density, a well-known pulse-width modulation (PWM) method is employed to control the activation time of the semiconductor laser  213  in accordance with the image density signal. In this method, the electrostatic latent image having an electric potential in response to the activation time of the semiconductor laser  213  is formed on the photosensitive drum  217 . Then, the respective colors of toner by an amount according to the electric potential of the latent image adhere to the photosensitive drum  217  by the developer units  219  through  222 , thereby developing the latent image. The developed image is then transferred to a transfer sheet wound around the transfer drum  223 . The image density is thus reproduced. 
     FIG. 3 is a timing chart illustrating the control operation for density reproduction performed in the printer  200 . 
     In FIG. 3,  10201  indicates a printer pixel clock, which corresponds to 400-dpi resolution. The pixel clock  10201  is generated by the laser driver  212 . Moreover, a 400-line (line/inch) triangular wave  10202  is produced in synchronization with the pixel clock  10201 . The triangular wave  10202  and the pixel clock  10201  have the same period. 
     400-dpi resolution image data (digital) signals having the respective M, C, Y and Bk colors, each having a 256-step gradation (8 bits), and a 200-line/400-line switching signal are transmitted to the laser driver  212  from the image signal processing unit  209  in synchronization with the clock of the image data pixels. The laser driver  212  synchronizes the above signals with the pixel clock  10201  by using a FIFO memory (not shown). The image data having the respective colors, each having 8 bits, is converted into an analog image signal  10203  by a digital-to-analog (D/A) converter (not shown) and is compared with the above-described 400-line triangular wave  10202 , thereby generating a 400-line PWM digital output signal  10204 . This digital image data changes from “00H” (H indicates hexadecimal) to “0FFH”, and thus, the 400-line PWM output signal  10204  has a pulse width in accordance with the above values. One period of the 400-line PWM output signal  10204  is 63.5 μm on the photosensitive drum  217 . 
     Further, the laser driver  212  produces not only the 400-line triangular wave  10202  but also a 200-line triangular wave  10205 , which has a period twice as long as the 400-line triangular wave  10202 , in synchronization with the pixel clock  10201 . Upon comparison of the 200-line triangular wave  10205  with the 400-dpi analog image signal  10203 , a 200-line PWM digital output signal  10206  is generated. The 200-line PWM output signal  10206  forms a latent image on the photosensitive drum  207  with a period of 127 μm, as shown in FIG.  3 . 
     Upon comparing density reproduction used by the 200-line triangular wave with density reproduction used by the 400-line triangular wave, a higher level of gradation reproducibility is achieved by the 200-line triangular wave because the minimum unit of the former wave for density reproduction is 127 μm, which is twice as long as the latter wave. In terms of resolution, however, the 400-line triangular wave that reproduces density by a 63.5 μm unit is more suitable for higher-resolution image recording. Consequently, 200-line PWM recording achieves a higher level of gradation reproduction, while 400-line PWM recording exhibits a higher level of resolution. To perform optimal density reproduction, therefore, PWM recording is switched between the 200-line triangular wave and the 400-line triangular wave in accordance with the nature of an image to be recorded. 
     For performing the above PWM switching operation, a 200-line/400-line switching signal  10207  is provided, as shown in FIG.  3 . The switching signal  10207  is input for each pixel into the laser driver  212  from the image signal processing unit  209  in synchronization with the 400-dpi image data. When the 200-line/400-line switching signal  10207  is at a logical low level (hereinafter referred to as “the L level”), the PWM output signal using the 400-line triangular wave is selected. In contrast, when the switching signal  10207  is at a logical high level (hereinafter referred to as “the H level”), the PWM output signal using the 200-line triangular wave is selected. 
     The configuration of the image signal processing unit  209  of the image scanner  201  is as follows. 
     FIG. 4 is a block diagram illustrating the flow of an image signal in the image signal processing unit  9  according to an embodiment of the present invention. An image signal output from the CCD  210  is input into an analog signal processing section  101  of the image signal processing unit  209 . In the analog signal processing section  101 , the gain and the offset of the signal are adjusted. The corrected signal is then output to an A/D converter  102  in which the analog signal is converted into digital image signals R 1 , G 1  and B 1  of the respective colors, each having 8 bits. Subsequently, the image signals R 1 , G 1  and B 1  are input into a shading correcting section  103  in which the shading of each of the image signals R 1 , G 1  and B 1  is corrected according to a known shading correction method using a signal read from the standard white plate  211 . The corrected signals R 2 , G 2  and B 2  are output. 
     Meanwhile, a clock generator  121  generates a clock (CLK) for each pixel. A main-scanning address counter  122  counts the number of clocks (CLK) from the clock generator  121  and generates a pixel address output signal for one line. A decoder  123  then decodes the main-scanning address output signal from the address counter  122  and produces the following signals: a CCD drive signal for each line, such as a shift pulse or a reset pulse, a VE signal representing the effective zone of a reading signal for one line output from the CCD  210 , and a line synchronizing signal HSYNC. The address counter  122  is reset by the HSYNC signal output from the decoder  123  and starts counting the number of clocks output from the clock generator  121  for a subsequent line. 
     An input masking section  106  converts a reading color space, which is determined by the spectral characteristics of the R, G and B filters  210 - 1 ,  210 - 2  and  210 - 3  of the CCD  210 , into an NTSC standard color space represented by R 4 , G 4  and B 4  according to the following matrix calculation.          [         R4           G4           B4         ]     =       [         a11       a12       a13           a21       a22       a23           a31       a32       a33         ]          [         R3           G3           B3         ]                       
     An image synthesizing section  1064  respectively synthesizes the image signals R 4 , G 4  and B 4  output from the image scanner  201  with the image signals Rif, Gif and Bif which are output from the film scanner  227  via the input masking section  106 . The calculations required for this synthesizing operation are as follows. 
     
       
           R 40 =R 4×COMP  R+Rif× (1-COMP  R ) 
       
     
     
       
           G 40 =G 4×COMP  G+Gif× (1-COMP  G ) 
       
     
     
       
           B 40 =B 4×COMP  B+Bif× (1-COMP  B ) 
       
     
     The elements COMP R, COMP G and COMP B are input by the operation performed through an operation section  1101  provided for the image processing apparatus. When all of the elements COMP R, COMP G and COMP B indicate “1”, an image read by the image scanner  201  is output. In contrast, when all of the elements COMP R, COMP G and COMP B indicate “0”, a film image read by the film scanner  227  is output. If the values between “0” and “1” are set in COMP R, COMP G and COMP B, an image signal from the image scanner  201  and a film image signal from the film scanner  227  are synthesized and output from the image synthesizing section  1064 . 
     An under-color processing section  1065  detects and removes under-color components of the image signals R 40 , G 40  and B 40  output from the image synthesizing section  1064 . 
     FIG. 5 is a block diagram illustrating the configuration of the under-color processing section  1065  used in this embodiment. 
     In FIG. 5, when the operation section  1101  sets an AE mode signal representing the removal of the under-color components, the under-color level detector  4001  samples document image signals which are obtained during the prescanning of the image scanner  201 , thereby producing density histograms of the respective image signals R 40 , G 40  and B 40 . Then, according to the respective density histograms, the values of the respective image signals obtained by the following procedure are determined as under-color level signals Rb, Gb and Bb. The density levels higher than a predetermined value “α” and also having a greater frequency than a predetermined ratio are first obtained. Among the above values, the value having the highest density level is then determined. 
     An example of a technique of determining an under-color level signal Rb based on a histogram is shown in FIG.  6 . 
     The under-color level signals Rb, Gb and Bb obtained by the under-color level detector  4001  are respectively converted into Re, Ge and Be according to the following equations and are input into an under-color removal section  4002 . 
     
       
           Re =(255 −Rb )×255×255/( Rb×Gb×Bb ) 
       
     
     
       
           Ge =(255 −Gb )×255×255/( Rb×Gb×Bb ) 
       
     
     
       
           Be =(255 −Bb )×255×255/( Rb×Gb×Bb ) 
       
     
     In the under-color removal section  4002 , the under-color components of the signals Re, Ge and Be are removed by performing a calculation using the following matrix equation, and the resulting signals R 5 , G 5  and B 5  are then output. It should be noted that the signals Re, Ge and Be required for this calculation are input from the under-color level detector  4001  during prescanning.          [         R5           G5           B5         ]     =       [         1       0       0       Re           0       1       0       Ge           0       0       1       Be         ]          [         R4           G4           B4             R4   ×   G4   ×   B4           ]                       
     If the user manually instructs the adjustment of the under-color level through the operation section  1101 , the signal indicating the adjusted level set by the user is input into the under-color level detector  4001  under the control of a CPU  1102 . Then, the under-color level detector  4001  outputs the predetermined values corresponding to the input under-color levels of the respective colors as Re, Ge and Be to the under-color removal section  4002 . 
     The above-described detecting operation by the under-color level detector  4001  may be performed using software according to the calculation based on the program of the CPU  1102 . 
     Referring back to FIG. 4, a light quantity/density converting section (a LOG converting section)  107 , which is formed of a look-up table (LUT) ROM, receives luminance signals R 5 , G 5  and B 5  output from the under-color processing section  1065  and converts them to density signals C 0 , M 0  and Y 0 , which are then output to a line delay memory  108 . The line delay memory  108  delays the density signals C 0 , M 0  and Y 0  for a predetermined number of lines. As a consequence, image signals C 1 , M 1  and Y 1  and the corresponding UCR signals with respect to the same pixel are simultaneously input into a masking/under color removal (UCR) circuit  109 . 
     The masking/UCR circuit  109  extracts a black (K) signal from the three primary color signals C 1 , M 1  and Y 1  and further performs a calculation for correcting apparent contamination of recording color materials (toner) to be used in the printer  200 . The resulting signals Y 2 , M 2 , C 2  and K 2 , each having 8 bits, are plane-sequentially output every time the reading operation is performed by the image scanner  201 . 
     A main-scanning variable-power circuit  110  enlarges and reduces the image signals Y 2 , M 2 , C 2  and K 2  in the main scanning direction by a known interpolation calculation and outputs the resulting signals Y 3 , M 3 , C 3  and K 3 . Further, a spatial-filter processing section (output filter)  111  switches between edge enhancement and smoothing processing in accordance with a two-bit FILTER signal input from a LUT  117 , which is described in detail later, and outputs the resulting signals Y 4 , M 4 , C 4  and K 4  to the printer  200 . 
     The image signals Y 4 , M 4 , C 4  and K 4 , and a SEN signal, which is a 200-line/400-line switching signal, are transmitted to the laser driver  212  of the printer  200 . The signals are then pulse-width modulated (PWM) and are recorded by the printer  200 . 
     FIG. 7 is a timing chart illustrating the control signals used in the image signal processing unit  209 . 
     In FIG. 7, a vertical synchronizing (VSYNC) signal represents the image effective zone in the sub-scanning direction. When the VSYNC signal indicates logical “1”, the image reading (scanning) is performed and the output signals (M), (C), (Y) and (K) are sequentially output. A VE signal, representing the image effective zone in the main scanning direction, provides timing for starting the main scanning operation in the logical “1” zone and is primarily used for controlling the counting of the lines to be delayed. A CLOCK signal designates a pixel synchronizing signal used in the image scanner  201 . When the CLOCK signal is at a rising edge timing “0”→“1”, image data read by the CCD  210  is transferred and supplied to the signal processors, such as the A/D converter  102  used in the image signal processing unit  209 . The CLOCK signal is also employed for transmitting the image signals and the 200-line/400-line switching (SEN) signal to the laser driver  212  of the printer  200 . 
     A description is now given of the image processing executed on photographic data transmitted from the film scanner  227  according to an embodiment of the present invention. 
     When an image recorded on the film is read and input with the film scanner  227 , photographic data concerning the input image signal is simultaneously read by the magnetic head  1 . In this embodiment, as an example of the photographic data, the focal length determined during a photographic operation is described. 
     Based on the photographic data concerning the focal length, the subject of the image signal may be estimated as follows. 
     
       
         
           
               
               
               
             
               
                   
                   
               
             
            
               
                   
                 Distant view 
                 landscape 
               
               
                   
                 Middle view 
                 portrait 
               
               
                   
                 Very close view 
                 characters 
               
               
                   
                   
               
            
           
         
       
     
     As a closer view is focused, the focus precision for the subject deteriorates. In view of this characteristic, the following adjustments may be made in order to perform the image processing considering the above correlations between the view and the subject. 
     1. When a distant view is focused, spatial filtering is performed so that a soft image is formed. 
     2. When a very close view is focused, spatial filtering is performed so that a sharp image is formed, and the level of UCR is intensified to improve the quality of the characters. 
     In FIG. 4, the focal length information Dis read by the film scanner  227  is input into the LUT  117 . Color information COL to be developed in the printer  200  is also input into the LUT  117 , and various signals (UCR signal, FILTER signal, and SEN signal) are generated, as shown in FIG. 8, based on the color information COL and the focal length information Dis. 
     FIG. 8 illustrates the relationship between the input data and the output data in the LUT  117 . The LUT  117  receives the focal length information Dis (two bits) read by the film scanner  227 . The information Dis is defined as follows. 
     
       
         
           
               
               
               
             
               
                   
                   
               
             
            
               
                   
                 Distant view: 
                 3 
               
               
                   
                 Middle view: 
                 2 
               
               
                   
                 Close view: 
                 1 
               
               
                   
                 Very close view: 
                 0 
               
               
                   
                   
               
            
           
         
       
     
     The developing color COL indicating “1” represents a black color, while the developing color COL designating “0” represents a color other than black. Thus, by a combination of the color information COL and the focal length information Dis, the levels of the following types of signals are determined: the masking-coefficient control signal (UCR) to be input into the masking/UCR circuit  109 , the output filter coefficient control signal (FILTER) to be input into the output filter  111 , and the 400-line/200-line switching signal (SEN) input into the printer  200 . The resulting signals are then output. 
     The UCR signal indicates the intensity level of the UCR operation: the intensity level decreases in the order of 0, 1, 2 and 3. The FILTER signal represents the enhancement level of an image edge: the edge enhancement decreases in the order of 0, 1, 2 and 3. The SEN signal “0” designates a 400-line signal, while the SEN signal “1” indicates a 200-line signal. 
     FIG. 8 shows that the LUT  117  sets the foregoing signals in the following manner when the image processing apparatus of this embodiment is under the standard condition. 
     1. UCR processing is performed with an increasingly intensified level as a closer view is focused (in case where the developing color is black). 
     2. The sharpness of an image (FILTER signal) is increased as a closer view is focused. The number of recording lines is set at  200  indicated by the SEN signal “1” unless otherwise instructed by the user through the operation section  1101 . The masking/UCR processing circuit  109  generates a black signal K and performs masking according to the UCR control signal (UCR) output from the LUT  117 . 
     The equations set out below illustrate masking/UCR equations performed in the masking/UCR processing circuit  109 . The minimum value MIN (C, M, Y) of C 1 , M 1  and Y 1  is first obtained to determine a black signal K 1  according to the equation ( 2101 ). Then, 4×8 masking is performed by using the equation ( 2102 ) so as to output C 2 , M 2 , Y 2  and K 2 . In this equation ( 2102 ), the coefficients m 11  through m 84  indicate masking coefficients determined by the printer  200 , while the coefficients k 11  through k 84  represent UCR coefficients determined by the UCR signal.                  K   1     =       -   255     ×     log        (       Min                 CMY     255     )            (     1   1.52     )                            (   2101   )                 (         C2           M2           Y2           K2         )     =       (           m11   ×   k11           m21   ×   k21           m31   ×   k31           m41   ×   k41           m51   ×   k51           m61   ×   k61           m71   ×   k71           m81   ×   k81               m12   ×   k12           m22   ×   k22           m32   ×   k32           m42   ×   k42           m52   ×   k52           m62   ×   k62           m72   ×   k72           m82   ×   k82               m13   ×   k13           m23   ×   k23           m33   ×   k33           m43   ×   k43           m53   ×   k53           m63   ×   k63           m73   ×   k73           m83   ×   k83               m14   ×   k14           m24   ×   k24           m34   ×   k34           m44   ×   k44           m54   ×   k54           m64   ×   k64           m74   ×   k74           m84   ×   k84           )          (         C1           M1           Y1           K1           C1M1           M1Y1           Y1C1           K1K1         )               (   2102   )                         
     In the spatial filter processing section (output filter)  111  shown in FIG. 4, two 5-pixel×5-pixel spatial filters are provided, and an output signal from one filter is connected to an input signal of the other filter. As the spatial filter coefficients, two types of smoothing (FILTER=3, 4) coefficients and two types of edge-enhancement (FILTER=0, 1) coefficients are provided and switched for each pixel in accordance with the level of the FILTER signal output from the LUT  117 . Further, by virtue of the two spatial filters, an edge enhancement operation is performed after a smoothing operation. It is thus possible to achieve edge enhancement with a decreased level of Moire fringing and also to output an image of higher quality by a combination of the two types of edge enhancement coefficients. 
     FIG. 9 is a flow chart illustrating the operation of generating a Dis signal indicating photographic information and a COL signal representing a developing color, the operation being performed by the CPU  1102  of the image signal processing unit  209  according to an embodiment of the present invention. 
     In step S 1 , the user inputs through the operation section  1101  the information representing a developing color (a color to be printed in the printer  200 ) and the number of lines for performing the PWM operation in the printer  200 . If the input developing color is monochrome, the COL signal is determined to be “1”. On the other hand, if the developing color is other than monochrome, the COL signal is determined to be “0”. The determined COL signal is then output to the LUT  117  in step S 2 . 
     In step S 3 , an image signal is input from the film scanner  227 . The image developed on the film  4  set in the film scanner  227  is read with the image scanner  7 , and the photographic data magnetically recorded on the film  4  is further read by the magnetic head  1 . Subsequently, in step S 4 , the level of the Dis signal is determined as discussed above based on the input photographic data, for example, the focal length of the image when the image has been taken. Then, the determined Dis signal is output to the LUT  117  in step S 5 . According to this procedure, the UCR coefficient used in the masking/UCR circuit  109 , the type of the spatial filter used in the spatial filter circuit  111 , and the number of lines used for the PWM processing in the printer  200  are determined. If it is found in step S 1  that the 200-line mode (SEN=1) to be used in the printer  200  has been instructed, the CPU  1102  does not particularly perform any operation. In contrast, if the 400-line mode (SEN=0) has been instructed, the SEN signal is directly changed to “1” and is output to the printer  200 . Alternatively, the information corresponding to “SEN=0” similar to the information shown in FIG. 8 is stored in the LUT  117 , and the information is selected and directly output to the printer  200 . 
     In the foregoing embodiment, UCR processing and filtering processing are modified based on photographic data (the focal length in this embodiment) recorded on the film. However, the auxiliary data used in the present invention is not restricted to photographic information, and magnetic information or information in the form of a bar code recorded on part of a document image may be read with the image scanner  201 , and based on the read information, UCR processing or filtering processing may be performed on the document image. Moreover, the photographic data is not limited to the focal length, and various types of information concerning images may be used, or data which is directly usable for masking processing or UCR processing may be employed. 
     According to the foregoing embodiment, since the information is magnetically stored in a storage medium, the quality of a resulting image is not impaired. Also, the auxiliary data may be not only magnetically recorded, but may also be recorded by using a developer which may be only responsive to ultraviolet rays. The advantages offered by the present invention using a developer are similar to those exhibited by the present invention using the magnetically recorded information. 
     The present invention may be applied to a system consisting of a plurality of devices (for example, a host computer, an interface, a reader, and a printer) or to a single device (for example, a copying machine or a facsimile machine). 
     Further, the present invention may be achieved by the following modification. A storage medium on which a software program code for implementing the function of the foregoing embodiment is recorded may be installed in a system or a device, and the program code stored in the storage medium may be read and run by a computer (or its CPU or MPU) of the system or the device. In this case, the program code itself read from the storage medium achieves the function of the foregoing embodiment, and accordingly, the storage medium in which the program code is stored may form the present invention. 
     The storage mediums for storing the program code may include floppy disks, hard disks, optical disks, magneto-optical disks, CD-ROMs, CD-Rs, magnetic tape, non-volatile memory cards, and ROMs. 
     The invention also encompasses the cases where the function of the foregoing embodiment is achieved not only when the program code read from the storage medium is run by a computer, but also when an operating system (OS) run on the computer partially or wholly executes the corresponding processing in response to the instruction of the program code. 
     The invention further encompasses the following case. The program code read from a storage medium may be written into a storage device provided in an extended-function board inserted into a computer or an extended-function unit connected to a computer. Then, the CPU provided in the extended-function board or the extended-function unit may partially or wholly perform the corresponding processing in response to the instruction of the program code, thereby implementing the function of the foregoing embodiment. 
     As is seen from the foregoing description, the present invention offers the following advantages. 
     An image signal is optically recorded on a recording medium, and at the same time, the corresponding auxiliary information is magnetically recorded on the recording medium. Then, a method for image processing performed on the image signal read from the recording medium is suitably determined based on the auxiliary information. Thus, optimal image processing is performed on the image input from the recording medium. 
     Further, an image and the corresponding auxiliary information, such as focal length information, are recorded on a recording medium by different methods and are read therefrom. Based on the auxiliary information, the image is efficiently color-processed or filtered. 
     While the present invention has been described with reference to what are presently considered to be the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. To the contrary, the invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.