JP3508169B2 - Signal processing device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal processing device suitable for use in a color correction circuit when performing so-called telecine, for recording a video signal of a cinema film photographed by a camera on a video tape recorder.

[0002]

2. Description of the Related Art Conventionally, so-called telecine (telecine) for converting image information of a film such as a movie into a television signal (video signal).
And a cinema compound word) device has been proposed.

This telecine device irradiates the film with light from a light source, scrapes the film one frame at a time by a scraping mechanism, and picks up the light of the film image with a video camera using a solid-state image sensor such as a CCD. Then, a video signal is obtained and this video signal is recorded on a video tape set in a video tape recorder.

Here, the above-mentioned telecine requires a signal processing device for recording a film video signal on a video tape recorder as shown in FIG. This signal processing device uses a video signal obtained by shooting a cinema film with a camera via an input terminal 40 and a buffer 41.
The analog signal is supplied to the D converter 42, the analog signal is converted to a digital signal by the A / D converter 42, and the non-linear processing circuit 43 performs γ correction, which is a correction unique to film photography, and then supplied to the output terminal 44. Then, this is recorded on a video tape recorder and reproduced on a television receiver.

[0005]

However, in the above-mentioned conventional signal processing circuit, since the cinema film itself for movies is based on orange, the state of the light source at the time of shooting and the processing state of the developing process at the time of development Alternatively, due to a change in the γ correction operating point of the non-linear processing circuit 43 or the like, there occurs a state in which the black level in the video signal of the film changes.

Here, since the gain of the operating point of the non-linear processing in the non-linear processing circuit 43 is large, it is necessary to quantize the change in the black level in addition to the video signal so that the quantization error is not greatly expanded. Therefore, an A / D converter with a large number of bits is required.

However, it is difficult to realize a high-speed A / D converter for video signals. Further, if A / D converters that are relatively slow and have a large number of bits are used in parallel, the circuit becomes large-scale and complicated. Therefore, it is difficult to realize such an A / D converter. Further, in this case, since the non-linear processing circuit is performed in the analog area, the circuit stability cannot be obtained, and there is a disadvantage that complicated non-linear processing cannot be realized.

The present invention has been made in consideration of the above points, and provides a signal processing apparatus for separately handling a video signal and a black level signal when the black level of the video signal of a film changes. It is intended.

[0009]

[Means for Solving the Problems]

The signal processing apparatus of the present invention irradiates the film with light from a light source , as shown in FIG.
The captured image of the film is picked up by the image pickup device, and the obtained
In a signal processing device that processes a log video signal,
Fluctuating component generation means 2 for generating a digital black level variation corresponding to the black level variation of the video signal, and a digital for converting the digital black level variation generated by the variation component generating means 2 into an analog black level variation. / Analog converter 3 and digital / analog from analog video signal
Subtract the analog black level fluctuation from the converter 3.
An analog subtractor 5, an analog / digital converter 7 which converts the output from the subtracter 5 into a digital signal, Ana
Di adding the variation of a digital black level of the output from the log / digital converter 7 from fluctuation components generated hand <br/> stage 2
A digital adder 10, the output from the digital adder 10
And a non-linear processing section 11 for performing non-linear processing of the film .

The signal processing apparatus of the present invention is shown in FIG.
The light from the light source is applied to the film as shown in
The image of the irradiated film is taken by the image pickup device and obtained.
In the signal processing device that processes the analog video signal,
A voltage generator 17 that generates a voltage corresponding to the fluctuation amount of the black level of the analog video signal, and a voltage from the analog video signal.
Subtract the analog fluctuation of the black level from the generator 17.
An analog subtractor 5, a first analog / digital converter 7, the black level of the analog variable <br/> dynamic content the black level from the voltage generator 17 for converting the output from the analog subtractor 5 into a digital signal and second analog / digital converter 19 for converting the digital variation, digital adder for adding outputs of the first analog / digital converter 7 and an output of the second analog / digital converter 19 10
And a non-linear processing unit 11 for performing non-linear processing of the film on the output from the digital adder 10.

[0012]

[0013]

[Action]

Further, according to the present invention described above, the fluctuation component of the black level signal of the input signal composed of at least the video signal and the black level signal is generated, the fluctuation component is converted into an analog signal, and the black level is converted from the input signal. Subtract the signal fluctuation,
This subtraction output is converted into a digital signal, this conversion output and the black level signal fluctuation component are added, and since this addition output is subjected to nonlinear processing, even if there is a fluctuation in the black level signal of the input signal, By separately processing the black level signal, the analog / digital converter 7 has the same number of bits as when the black level signal of the input signal does not change.
Can be used.

Further, according to the present invention described above, the variation of the black level signal of the input signal consisting of at least the video signal and the black level signal is generated, the variation of the black level signal is subtracted from the input signal, and the subtraction output Is converted into a digital signal, the fluctuation of the black level signal is converted into a digital signal,
Since the first analog / digital conversion output and the second analog / digital conversion output are added and this addition output is subjected to nonlinear processing, even if the black level signal of the input signal varies, the video signal of the input signal and the black signal By processing the level signal separately, the analog / digital converter 7 having the same number of bits as in the case where the black level signal of the input signal does not change can be used.

[0016]

[0017]

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the signal processing apparatus of the present invention will be described in detail below with reference to FIGS. The signal processing device of the present invention, as shown in FIG. 3, captures a cinema film for a movie with a camera 24 to obtain a video signal, which is recorded on a video tape recorder 27 and reproduced on a monitor 29 such as a television receiver. It is used in a so-called telecine system.

This telecine system is constructed as shown in FIG. Each of them is installed so that the image magnified by the cinema scope lens 21 is projected on a screen (not shown) by the projector 20.
Here, a lens 23 and a high-definition camera 24 are provided so that the cinema film can be photographed via an adapter 22 that converts the cinema film into a film having a size of 36 mm to 16 mm.

A processor 25 for processing the video signal from the high-definition camera 24 is provided. The processor 25 includes an I / O circuit 15 that processes input / output signals, a noise reducer and image enhancer circuit 9 that performs noise removal and edge enhancement operations, and a color collector circuit 16 that performs color correction. The signal processing device of the present invention corresponds to the I / O circuit 15 and the color collector circuit 16.

The video signal output from the processor 25 is supplied to the matrix circuit 26. The video tape recorder 2 so that the video signal from the matrix circuit 26 is supplied.
7 and a frame memory 28 are provided. The matrix circuit 28 generates color difference signals RY and BY and a luminance signal Y from the primary color signals R, G and B signals. Then, a monitor 29 for supplying a video signal from the video tape recorder 27 and the frame memory 28 to watch the video is provided.

An analog signal processing circuit 30 for performing signal processing such as shaping the analog audio 2-channel signal from the projector 20 is provided. A Dolby circuit 31 for supplying the analog audio two-channel signal from the analog signal processing circuit 30 and converting it to a digital audio signal is provided, and the digital audio signal is supplied to the video tape recorder 27.

The workstation 32 has a keyboard 35.
And a main CPU 33. The workstation 32 supplies the control signals for this system.
A control signal line for supplying a control signal from the workstation 32 to the analog audio signal processing circuit 30 is provided. The workstation 32 is connected to the projector 20, the control panel 34, and the video tape recorder 27 via the RS-422 interface. Further, the workstation 32 is provided with a color collector circuit 16, a noise reducer and image enhancer circuit 9, an I / O circuit 1 through a SCSI interface.
5, and is connected to the frame memory 28.

The telecine system configured as above operates as follows. The operator operates the control panel 34 and the keyboard 35 of the workstation 32 to operate the I / O circuit 15 of the processor 25.
Supplies a control signal and a cam sync signal to the high-definition camera 24. At the same time, the project sync signal is supplied to the projector 20. As a result, the high-definition camera 24 shoots a cinema film (not shown) set on the projector 20 to generate a video signal.

The video signal is supplied to the I / O circuit 15 for input / output signal processing. The video signal is supplied to the noise reducer and image enhancer circuit 9 for noise removal and contour enhancement. The video signal is supplied to the color corrector circuit 16 for color correction. The operation of the signal processing device of the present invention corresponds to the operation of the I / O circuit 15 and the color collector circuit 16.

The video signal from the processor 25 is supplied to the matrix circuit 26 according to the signal standard SMPTE260M. The matrix circuit 26 generates RY, BY, and Y signals from the R, G, and B signals. The video signal is supplied from the matrix circuit 26 to the video tape recorder 27 and the frame memory 28 according to the signal standard SMPTE260M. The video signals from the video tape recorder 27 and the frame memory 28 are signal standards S respectively.
It is supplied to the monitor 29 by MPTE240M. Separately from this, the video signal is directly supplied from the processor 25 to the monitor 29 according to the signal standard SMPTE240M.

Next, the operation of the audio signal will be described.
The analog audio 2-channel signal from the projector 20 is supplied to the analog signal processing circuit 30 and subjected to signal processing such as shaping. The analog audio 2-channel signal from the analog signal processing circuit 30 is supplied to the Dolby circuit 31 and converted into a digital audio signal.
This digital audio signal is supplied to the video tape recorder 27. In the video tape recorder 27, this digital audio signal is recorded on a tape, reproduced, and then supplied to the monitor 29 for listening.

The control signal will be further described. A control signal is supplied from the workstation 32 to the analog audio signal processing circuit 30 to control the audio signal.
The control signal from the workstation 32 is RS-422.
The projector 20 is supplied to the projector 20 and the video tape recorder 27 via the interface.
The operation of the video tape recorder 27 can be controlled.

The workstation 32 also supplies control signals to the three circuits of the color collector circuit 16, the noise reducer and image enhancer circuit 9, and the I / O circuit 15 in the processor 25 through the SCSI interface. It enables the operation of the circuit. Further, the workstation 32 supplies a control signal to the frame memory 28 via the SCSI interface to control a video signal supplied to the monitor 29.

As described above, the high-definition camera 24 shoots a cinema film (not shown) set in the projector 20 to create a video signal, and the processor 25 performs predetermined signal processing on the video signal to produce a video signal. Monitor 2 by supplying video signal to tape recorder 27
You can watch the video at 9.

The processor 25 in the above-mentioned telecine system is constructed in detail as shown in FIG.
Here, only the path of the video signal is shown and the path of the control signal is omitted. Main CPU 3 in workstation 32
A system control unit 2 is provided at 3. The output from the system controller 2 is supplied to the adder 10 and D / A
It is supplied to the converter 3. The output of the D / A converter 3 is supplied to the subtractor 5 via the buffer 4. The video signal supplied to the input terminal 1 is supplied to the addition input of the subtracter 5. Here, the signals supplied to the adder 10 and the subtractor 5 are generated by the system control unit 2. This signal is added to the adder 10 as it is, and the subtractor 5 D / A converts it into an analog amount, which is exactly "-1 time".
Are converted so as to be added and added.

A 10-bit A / D converter 7 is provided so that the 10-bit analog signal which is the subtraction output of the subtractor 5 can be converted into a 10-bit digital signal via the buffer 6. An S / P converter 8 for converting the serial signal output of the 10-bit A / D converter 7 into a parallel signal output is provided. S /
A noise reducer and image enhancer circuit 9 that removes noise from the parallel signal output of the P converter 8 and enhances the contour is provided at the subsequent stage of the S / P converter 8.

The output of the noise reducer and image enhancer circuit 9 is supplied to the addition input of the adder 10. A non-linear processing circuit 11 for γ-correcting the addition output of the adder 10 is provided. Here, since the non-linear processing can be performed in the digital domain that has already been converted into a digital signal by the 10-bit A / D converter 7, it is possible to stably perform complicated processing that cannot be realized in the analog domain. it can. The output of the non-linear processing circuit 11 is supplied to the noise reducer and image enhancer circuit 9. This noise reducer and image enhancer circuit 9
Is the same as described above.

A P / S converter 12 for converting the parallel signal output of the noise reducer and image enhancer circuit 9 into a serial signal output is provided. D / which converts the digital signal output of the P / S converter 12 into an analog signal output
An A converter 13 is provided and its output is supplied to the output terminal 14. Here, the subtracter 5, the buffer 6, and the 10-bit A / D
Converter 7, S / P converter 8, D / A converters 3, 13, P
The portion of the / S converter 12 constitutes the I / O circuit 15. Further, the adder 10 and the non-linear processing circuit 11 constitute a color collector circuit 16. The I / O circuit 15 and the color collector circuit 16 correspond to the signal processing device of the present invention.

The processor configured as described above operates as follows. The system control unit 2 generates the fluctuation amount of the black level signal of the input signal including the video signal and the black level signal supplied to the input terminal 1. The fluctuation of the black level signal is supplied to the adder 10 and D / A
It is supplied to the converter 3. The analog signal, which is the variation of the black level signal, is converted into an analog signal in the D / A converter 3. The fluctuation amount of the black level signal converted into the analog signal is supplied to the subtraction input of the subtractor 5 via the buffer 4.

Here, since the input signal consisting of the video signal and the black level signal is supplied from the input terminal 1 to the subtraction input of the subtractor 5, the black level fluctuation is subtracted in the subtractor 5 and the video signal is subtracted. Only the subtraction output. This video signal is passed through the buffer 6 to the 10-bit A / D converter 7
Is supplied to. The 10-bit A / D converter 7 converts an analog video signal into a digital video signal.
This is for performing non-linear processing in the digital domain converted into a digital signal in the non-linear processing circuit 11 in the subsequent stage. This makes it possible to stably perform complicated non-linear processing that cannot be realized in the analog domain. The black level fluctuation is subtracted by the analog area subtractor 5 and added by the digital area adder 10. Therefore, only the 10-bit video signal is converted into the 10-bit A / D signal.
Since it can be converted into a digital signal in the converter 7, these can be realized with a simple configuration.

FIG. 6 shows the flow of the input signal from the input terminal 1 to the adder 10 described above. A, b, shown here
Each point of c and d shows each measurement point in FIG. The black level of the signal at point a indicating the video signal and the black level signal of the input signal supplied to the input terminal 1 is changed. Next, b obtained by subtracting the change in black level in the analog area
The point signal is only a 10-bit video signal. As a result, a 10-bit A / D converter can be used. The signal at point c is a signal in which the black level does not change is converted into a 10-bit digital signal.

The signal at the point d is reproduced by digitally adding the black level subtracted signal before the A / D conversion to the black level changed signal. In this way, the signal at point d has 11 bits, and the result equivalent to using the 11-bit A / D converter can be obtained without increasing the quantization error. Here, since it is known how much the voltage in the analog area will be in the digital area, for example, the voltage at the point b is measured with an oscilloscope or the like so that the change in the black level is eliminated. And

Further, the video signal subjected to the non-linear processing in the non-linear processing circuit 11 is supplied to the noise reducer and image enhancer circuit 9 for noise removal and contour enhancement. The P / S converter 12 converts the parallel signal output into a serial signal output. Furthermore D
The / A converter 13 converts the digital signal output into an analog signal output and supplies it to the output terminal 14.

As described above, the processor is the I / O circuit 1
5, the noise reducer and image enhancer circuit 9 and the color collector circuit 16 can perform their respective operations. Further, at the same time, the signal processing device of the present invention subtracts the fluctuation amount of the black level from the input signal composed of the video signal and the black level signal to obtain 1
By converting only the 0-bit video signal into a digital signal in the 10-bit A / D converter 7 and adding the fluctuation amount of the black level to the converted digital video signal,
It can be easily configured by the A / D converter 7 having a small number of bits. As a result, the 10-bit A / D converter 7
Since the nonlinear processing circuit 11 can perform the nonlinear processing in the digital area that has already been converted into the digital signal, the complicated processing that cannot be realized in the analog area can be stably performed.

In this case, as shown in FIG. 4, when the black level of the input signal does not change, only the 10-bit video signal can be subjected to the non-linear processing in the non-linear processing circuit 11. At this time, since it is not necessary to perform subtraction and addition of the black level by the subtractor 5 and the adder 10, the subtractor 5
Also, the processing is performed without using the adder 10 and is supplied to the nonlinear processing circuit 11. This black level becomes an operating point in nonlinear processing. A / D conversion is performed with 10 bits for the entire area from the black level to the white level of the video signal. This is to prevent the quantization error from being emphasized in the non-linear processing circuit 11.

However, as shown in FIG. 5, when the black level changes, assuming that the entire area from the black level to the white level of the video signal is 10 bits, in addition to the 10-bit video signal, the 1-bit black level 11 bits are required because there is a fluctuation of This is to prevent the quantization error from being emphasized in the non-linear processing circuit 11. In this case, since the operating point changes, the non-linear processing of 11 bits complicates the circuit scale. In the present invention, even when the black level, that is, the operating point is changed in this way, the change amount of the black level is subtracted, so that the 10-bit A / D converter 7 having the same number of bits as when the black level does not change can be used. it can.

According to the above example, the low-frequency fluctuation component of the input signal including at least the high frequency band and the low frequency band is generated, the generated fluctuation component is converted into an analog signal, and the low frequency band generated from the input signal is generated. The fluctuation is subtracted, the subtracted output is converted to a digital signal, and the converted output and the generated fluctuation are added, so even if there is fluctuation in the low range of the input signal, the high range of the input signal By separately processing the low frequency band and the low frequency band, it is possible to use the A / D converter 7 having the same number of bits as when the low frequency band of the input signal does not change.

Further, according to the above example, the fluctuation of the black level signal of the input signal composed of at least the video signal and the black level signal is generated, and this fluctuation is converted into an analog signal,
The black level signal fluctuation is subtracted from the input signal, this subtraction output is converted to a digital signal, this conversion output and the black level signal fluctuation are added, and this addition output is subjected to nonlinear processing. Even if there is fluctuation, the video signal of the input signal and the black level signal are processed separately so that the number of bits of the A / D converter 7 is the same as that of the case where the black level signal of the input signal does not vary. Can be used.

Further, the processor may be constructed as shown in FIG. In this case, the difference from the configuration of the processor shown in FIG. 1 is as follows. The variable resistor 17 is used instead of the system control unit 2 in FIG. The variable resistor 17 generates the fluctuation amount of the black level signal of the input signal composed of the video signal and the black level signal supplied to the input terminal 1. It goes without saying that the operation of such a processor is the same as that described in FIG. Here, the signal generated by the variable resistor 17 is directly supplied to the subtractor 5. The signal supplied to the subtractor 5 is converted and added to the adder 10 so that the signal supplied to the subtractor 5 becomes exactly "-1" when the digital amount is obtained by A / D conversion.

Further, according to the above example, the fluctuation amount of the black level signal of the input signal including at least the video signal and the black level signal is generated, the fluctuation amount of the black level signal is subtracted from the input signal, and the subtraction output is digitalized. The signal is converted into a digital signal, the fluctuation of the black level signal is converted into a digital signal, the first analog / digital conversion output and the second analog / digital conversion output are added, and the addition output is nonlinearly processed. A / D converter having the same number of bits as when the black level signal of the input signal does not change by separately processing the video signal of the input signal and the black level signal even when the black level signal of the signal changes 7 can be used.

The case where the video signal has a black level change has been described above. FIG. 7 shows the case where the carrier signal is superimposed on the baseband signal. The signal processing circuit used at this time is the same as that shown in FIG. 1 or FIG. 2, and therefore detailed description thereof will be omitted. High-speed A / D converter 7
Has a small number of bits, and in such a case, the dynamic range is insufficient due to the amplitude component of the baseband signal. Therefore, the same processing as in the case of subtracting the change amount of the black level signal in the video signal is performed.

That is, the baseband signal is subtracted in the analog domain before A / D conversion to generate only an 8-bit carrier signal. Next, only the 8-bit carrier signal whose dynamic range is suppressed is converted by the high-speed A / D converter 7. The baseband signals are added in the digital domain converted by the A / D converter 7 to reproduce the superimposed signal. As a result, a high-speed A / D equivalently having many bits
The converter is obtained.

Further, according to the above example, since the low band of the input signal is the baseband signal and the high band of the input signal is the carrier signal, when the carrier signal is superimposed on the baseband signal, the input signal is The number of bits of the A / D converter 7 can be reduced by separately processing the baseband signal and the carrier signal of.

Further, according to the present invention described above, the video signal is a video signal obtained by shooting a film by the camera 24, and the output of the non-linear processing circuit is the video tape recorder 27.
Since it is supplied to and recorded on the film, the video signal obtained by photographing the film and the black level signal are separately processed, so that the bit number of the A / D converter 7 is reduced by the bit number of the black level signal to perform the signal processing. It can be supplied to the video tape recorder 27. The above-described embodiment is an example of the present invention, and it goes without saying that various other configurations can be adopted without departing from the scope of the present invention.

[0051]

【The invention's effect】

Further, according to the present invention described above, the variation of the black level signal of the input signal consisting of at least the video signal and the black level signal is generated, the variation is converted into an analog signal, and the black level is converted from the input signal. Subtract the signal fluctuation,
This subtraction output is converted into a digital signal, this conversion output and the black level signal fluctuation component are added, and since this addition output is subjected to nonlinear processing, even if there is a fluctuation in the black level signal of the input signal, By processing the black level signal separately, it is possible to use an analog / digital converter having the same number of bits as in the case where the black level signal of the input signal does not change.

Further, according to the present invention described above, the variation of the black level signal of the input signal consisting of at least the video signal and the black level signal is generated, the variation of the black level signal is subtracted from the input signal, and the subtraction output Is converted into a digital signal, the fluctuation of the black level signal is converted into a digital signal,
Since the first analog / digital conversion output and the second analog / digital conversion output are added and this addition output is subjected to nonlinear processing, even if the black level signal of the input signal varies, the video signal of the input signal and the black signal By processing the level signal separately, it is possible to use an analog / digital converter having the same number of bits as when the black level signal of the input signal does not change.

[0054]

[0055]

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a telecine system using an embodiment of a signal processing device of the present invention.

FIG. 2 is a block diagram showing a configuration of an embodiment of a signal processing device of the present invention.

FIG. 3 is a block diagram showing the configuration of another embodiment of the signal processing device of the present invention.

FIG. 4 is a diagram illustrating an input signal (A) and an operation (B) of a non-linear circuit when the black level (operating point) of the signal processing device of the present invention does not change.

FIG. 5 is a diagram illustrating an input signal (A) and an operation (B) of a non-linear circuit when the black level (operating point) of the signal processing device of the present invention changes.

FIG. 6 is an operation (A) of an input signal of the signal processing device of the present invention.
It is a figure explaining- (D).

FIG. 7 is a diagram for explaining an operation when a carrier signal (high band) is superimposed on a baseband signal (low band) in the signal processing device of the present invention.

FIG. 8 is a block diagram showing a configuration of a conventional signal processing device.

[Explanation of symbols]

1 input terminal 2 System control unit 3 D / A converter 4 buffers 5 subtractor 6 buffers 7 A / D converter 8 S / P converter 9 Noise reducer and image enhancer circuit 10 adder 11 Non-linear processing circuit 12 P / S converter 13 D / A converter 14 output terminals 15 I / O circuit 16 color collector circuit 17 Variable resistor 18 buffers 19 Low speed A / D converter 20 projector 21 Cinemascope lens 22 16mm adapter 23 lenses 24 HD camera 25 processors 26 Matrix circuit 27 Video Tape Recorder 28 frame memory 29 monitors 30 Analog audio signal processing circuit 31 Dolby circuit 32 workstations 33 Main CPU 34 Control panel 35 keyboard

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Claims (2)

(57) [Claims] 1. A film is irradiated with light from a light source,
The image of the irradiated film is taken by the image pickup device and obtained.
In the signal processing device for processing the analog video signal, the data corresponding to the variation of the black level of the analog video signal
Digital converting the fluctuation component generating means for generating Ijitaru black level variation, a digital black level variation generated by the fluctuation component generating means into an analog black level variation /
An analog converter and the above digital / analog converter from the above analog video signal.
An analog subtractor for subtracting the analog black level fluctuation from the converter, an analog / digital converter for converting the output from the subtractor into a digital signal, and an output from the analog / digital converter. A signal processing apparatus comprising: a digital adder for adding the fluctuation amount of the digital black level from the fluctuation component generating means; and a non-linear processing section for performing non-linear processing of the film on the output from the digital adder. 2. A film is irradiated with light from a light source,
The image of the irradiated film is taken by the image pickup device and obtained.
In the signal processing device for processing the analog video signal, the signal corresponding to the variation of the black level of the analog video signal
A voltage generator for generating a pressure and a black level from the voltage generator from the analog video signal.
Black and analog subtractor for subtracting the analog variation Le, a first analog / digital converter for converting the output from the analog subtractor into a digital signal, an analog variation of the black level from said voltage generator Les
De adding the second analog / digital converter for converting the digital variation of the bell, the outputs of the said second analog / digital converter of the first analog / digital converter
A signal processing device comprising: a digital adder; and a non-linear processing unit for performing non-linear processing of a film on an output from the digital adder.