JPH11261927A - Display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a display picture similar to a picture at the time of projection by removing a field duplicated in conversion so as to generate a video signal with a specific successive scanning to drive a display panel. SOLUTION: When an inputted video signal is a telecine-converted picture using a 2-3 pull down system, a successively scanned video signal supplied through a switch 6 in response to a memory control signal from a control means 8 is alternately written in frame memories 4 and 5 by thinning a field of the same picture patterns and is alternately read out in 24 Hz by a reading control means 9. When the inputted video signal is a telecine-converted picture, an address driver 10 drives a display panel 12 to a display together with a sustain driver 11 by a frame rate of 24 Hz in response to a driving control signal supplied from a control signal 3. When the inputted video signal is a general picture, the driver 10 drives the display panel 12 to display together with the sustain driver 11 by a frame rate of 60 Hz in response to a driving control signal supplied from a control means 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel (PDP) capable of displaying a high-quality telecine-converted video signal in which an input video signal is generated from a cinema film by a 2-3 pull-down method, and electroluminescence. The present invention relates to a matrix display device such as an (EL) panel and a liquid crystal panel.

[0002]

2. Description of the Related Art A video signal of a cinema film is often included in a video signal of a standard television system such as the NTSC system. Movie film is 2 per second
There are four frames (frames). On the other hand, the video signal of the standard television system is an interlaced video signal in which one frame is composed of two fields at 30 frames per second. For this reason, a cinema film is telecine-converted by a 2-3 pull-down system to obtain a video signal of a standard television system.

In the 2-3 pull-down method, the first and second fields of the first frame to the first frame of the movie film, the first and second fields of the second frame to the second frame, and the first field of the third frame are used. , The second field of the third frame and the first field of the fourth frame are created from the third frame. Thereafter, similarly, from each frame of the continuous film, two fields, three fields,
Video signals for fields, 3 fields,... Are created. In this way, two frames of the movie film are made to correspond to five fields of the video signal of the standard television system, and the video signal of the two fields and the video signal of the three fields are alternately repeated corresponding to the frame of the movie film. Is converted to a signal.

[0004] When displaying the interlaced scanning video signal thus telecine-converted on a display device such as a PDP, for example, in the above-mentioned third frame, the images of the second and third frames of the cinema film are combined. Therefore, there is a problem that the image quality is inferior to the original movie film image.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a display device having improved reproduction quality for a telecine-converted image.

[0006]

According to a first aspect of the present invention, a display device detects whether or not an input video signal is a 60-Hz field unit telecine-converted video signal obtained by telecine-converting a 24 Hz film source. Detecting means for detecting the input video signal as a telecine-converted video signal, removing an overlapped field during the telecine conversion from the telecine-converted video signal to generate a 24 Hz progressively scanned video signal; Signal processing means, 24Hz
And a display panel driving means for driving the display panel with the video signal of the sequential scanning.

The display device according to the second aspect of the present invention includes a progressive scan conversion means for converting an input interlaced scan video signal into a progressive scan video signal, and an input interlace scan video signal of 24 Hz. Detecting means for detecting whether or not a 60 Hz field-based telecine converted video signal obtained by telecine converting the film source of
Frame memory control means for controlling writing of the converted progressively scanned video signal to the frame memory and reading from the frame memory, and display panel driving for driving the display panel with the progressively scanned video signal read from the frame memory Means for detecting the input video signal as a telecine-converted video signal by the detection means, the progressive scan conversion means generates a progressively scanned video signal by inter-field interpolation using fields of the same film frame. The frame memory control means is characterized in that fields of the same picture are thinned out and written into the frame memory, and read out from the frame memory at 24 Hz.

[0008] Further, the invention described in claim 3 is based on claim 2.
Wherein the frame memory control means performs writing to and reading from the frame memory at 60 Hz when the detection means detects that the input video signal is not a telecine-converted video signal. Features.

[0009] The invention described in claim 4 is the invention according to claim 3.
Wherein the detecting means detects whether or not the signal is a telecine-converted video signal for each field based on a correlation with the preceding and succeeding fields.

[0010]

According to the display device of the present invention, when the input video signal is 24
It is configured to detect whether or not it is a video signal obtained by conversion from a film source of 24 Hz, remove a field duplicated at the time of conversion, generate a video signal of 24 Hz progressive scanning, and drive the display panel. Therefore, it is possible to display a display image with the same number of frames as when projecting a film,
An image closer to film projection can be obtained as compared with the case of reproducing with a 0 Hz field unit NTSC signal.

[0011]

FIG. 1 is an overall block diagram of a display device according to an embodiment of the present invention. In FIG. 1, the display device comprises a sequential scan conversion means 1, a film mode detection means 2, a control means 3, frame memories 4 and 5, a write control means 8 for controlling writing / reading of the frame memories 4 and 5, and a read control means. 9 and frame memory 4,
Switch 6 for alternately selecting write and read of No. 5,
Signal processing means comprising an address driver 1
0, a display panel driving means including a sustain driver 11, and a display panel 12 such as a plasma display panel (PDP).

First, NTSC having a frame frequency of 30 Hz
The input video signal obtained by the interlaced scanning of the system is input to the progressive scan conversion means 1 and the film mode detection means 2.

The film mode detecting means 2 integrates, for example, the absolute value of the difference between frames for one field period, compares the integrated value with a predetermined threshold value, , The others are determined to be still fields. In the case of an image (film image) converted by the 2-3 pull-down method, a still field is generated every five fields. This periodic pattern is detected to determine whether the image is a film image (telecine-converted image) or a general image, and the detection information is sequentially converted by the scan conversion means 1 and the control means 3.
To supply.

The progressive scan conversion means 1 responds to the detection information from the film mode detection means 2 to generate an interpolation scan signal by an intra-field interpolation process and / or an inter-field interpolation process, and generates an actual scan signal and a video signal. By interpolating the interpolated scanning signals, the interlaced scanning video signals are converted into progressive scanning video signals.

Here, when the input video signal is a telecine-converted image converted by the 2-3 pull-down method, in response to the detection information from the film mode detecting means 2, the progressive scan converting means 1 A progressively scanned video signal is generated by inter-field interpolation using fields.

On the other hand, when the input video signal is a general image generated by a television camera or the like, the progressive scan conversion means 1 responds to the detection information from the film mode detection means 2 by a normal motion adaptive interpolation processing. To generate a video signal of progressive scanning.

The control means 3 comprises a film mode detecting means 2
Supplies a memory control signal to the write control means 8 and the read control means 9 for controlling the writing / reading of the frame memories 4 and 5 respectively in response to the detection information, and the writing and reading of the frame memories 4 and 5 are alternately performed. A switching signal to be selected is supplied to switches 6 and 7, and
A drive control signal is supplied to a sustain driver 11 that drives the display panel 12.

The switch 6 is switched in response to a switching signal output from the control means 3, and switches the sequential scan conversion means 1.
, The video signals converted into the sequential scanning signals are alternately relayed to the frame memories 4 and 5.

The writing and reading of the video signals supplied to the frame memories 4 and 5 via the switch 6 by the writing control means 8 and the reading control means 9 are controlled.
If one is in the write state, the other is in the read state.

Here, when the input video signal is a telecine-converted image converted by the 2-3 pull-down method, the switch 6 responds to the memory control signal from the control means 8.
Of the same picture by the write control means 8 and alternately write them to the frame memories 4 and 5 by the write control means 8, and alternately read from the frame memories 4 and 5 at 24 Hz by the read control means 9. read out.

On the other hand, when the input video signal is a general image generated by a television camera or the like, in response to the memory control signal from the control means 8, the progressive video signal supplied via the switch 6 is transmitted. The writing control means 8 and the reading control means 9 are controlled so as to write and read at 60 Hz.

The switch 7 switches in response to a switching signal output from the control means 3, and switches the frame memory 4,
5 are relayed to the address driver 10 in the sequential scanning video signal alternately read out from the address driver 10. The address driver 10 drives the display panel 12 together with the sustain driver 11 to perform display based on the sequentially scanned video signals read alternately from the frame memories 4 and 5.

If the input video signal is a telecine-converted image converted by the 2-3 pull-down method, the address driver 10 displays the image together with the sustain driver 11 in response to the drive control signal supplied from the control means 3. The display is performed by driving the display panel 12 at a frame rate of 24 Hz.

On the other hand, when the input video signal is a general image generated by a television camera or the like, in response to the drive control signal from the control means 8, the address driver 10 drives the display panel 12 together with the sustain driver 11 by 60H.
The display is driven by driving the display panel 12 at the rate of z.

Next, the operation of converting an interlaced scanning video signal (NTSC signal) telecine-converted by the 2-3 pull-down method into a progressive scanning video signal will be described with reference to FIG.

FIG. 2A shows a non-interlaced video signal with a frame frequency of 24 Hz generated from a movie film, and FIG. 2B shows a non-interlaced video signal with a frame frequency of 24 Hz in a 2-3 pull-down system. 3 shows an interlaced NTSC signal having a frame frequency of 30 Hz, which has been telecine-converted. FIG. 2C shows FIG.
The actual scanning line of the NTSC signal in (b) is indicated by a circle, and the interpolated scanning line to be inserted during sequential conversion is indicated by a square.

As described above, when the input video signal is a telecine-converted image converted by the 2-3 pull-down method, the progressive scan conversion means 1 responds to the detection information from the film mode detection means 2 and A video signal for progressive scanning is generated by inter-field interpolation using the fields of the frame. That is, for example, the interpolated scanning line of the field Ac2 is interpolated by an actual scanning line adjacent to the field Ac1 one field before constituting the same film frame, and the interpolated scanning line of the field Bcl is one field constituting the same film frame. Interpolated by the actual scanning line adjacent to the subsequent field Bc2,
The interpolation scanning line c2 is interpolated by an actual scanning line adjacent to the field Bc1 one field before or after one field constituting the same film frame.

FIG. 3 is a diagram showing the timing of writing the video signals that have been sequentially scanned and converted to the frame memories 4 and 5 and the timing of reading the video signals from the frame memories 4 and 5. The input video signals shown in FIG. 3A are Ac1, Ac2
... 60Hz by 2-3 pull down conversion like Fc2
It is assumed that a 2-3 periodic pattern is discontinuous due to editing or the like in the field indicated by the mark X.

For an input video signal as shown in FIG. 3A, the film mode detecting means 2 detects that a still field occurs every five fields as described above, and converts the input video signal to a telecine-converted image. Is determined, and in response to this, the progressive scan conversion means 1 generates progressive scan video signals by inter-field interpolation using fields of the same film frame.

As shown in FIG. 3B, the video signal which has been subjected to the sequential scan conversion is first converted into a field Ac.
1 is written into the frame memory 4 via the switch 6,
Writing is not performed on the next same pattern field Ac2, the next field Bc1 is written into the frame memory 5 via the switch 6, and writing is performed on the next same pattern field Bc2, Bc1. , The next field Cc2 is written to the frame memory 4 via the switch 6, the next field Dc2 is not written to the next field Cc1 of the same pattern, and the next field Dc2 is
Is written to the frame memory 5 via the. In this way, writing to the frame memories 4 and 5 is performed intermittently. The writing to the frame memories 4 and 5 is performed as follows.
This is performed in synchronization with reading from the frame memories 4 and 5 described later.

On the other hand, the video signals written in the frame memories 4 and 5 are alternately read at 24 Hz from the frame memories 4 and 5 as shown in FIG. That is,
The field Ac1 is read from the frame memory 4 at 24 Hz, and then the field Ac1 is read from the frame memory 5
1 is read at 24 Hz, and then field Cc1 is read from frame memory 4 at 24 Hz.

In this manner, writing to the frame memories 4 and 5 is performed intermittently in synchronization with reading from the frame memories 4 and 5, and reading is continuously and alternately performed at 24 Hz from the frame memories 4 and 5. As a result, a sequential scanning signal having a frame frequency of 24 Hz including the fields Ac1, Bc1, and Cc1 shown in FIG. 3C is obtained.

Here, when the 2-3 periodic pattern becomes discontinuous due to editing or the like as in the field indicated by the X mark shown in FIG. 3A, the film mode detecting means 2 converts the telecine-converted image from the telecine-converted image. Images that are not images (2
A field which switches to a (-3 pattern periodic image) is detected. In response to this, the write control means 8 and the read control means 9 perform the operations shown in FIG.
As shown in (1), writing / reading to / from the frame memories 4 and 5 is continuously performed at 60 Hz, and signals read from the frame memories 4 and 5 are 60 Hz sequential scanning signals. In response to the 60 Hz progressive scanning signal, the address driver 10 drives the display panel 12 together with the sustain driver 11 to drive the display panel 12 at a rate of 60 Hz to perform display.

FIG. 4 shows the film mode detecting means 2 shown in FIG.
2 shows another configuration example. The first correlation detector 211 detects the actual scanning signals (the video signal S5 and the video signal S4 in FIG. 4 and the bc of the field Bc1 in FIG.
1, bc3) and the absolute value (| bc1-ac2 |) of the inter-field difference between the pixels of the actual scanning signal (the video signal S3 in FIG. 4, for example, ac2 of the field Ac2 in FIG. 2) of the field one field before. | Bc3-ac2 |), and outputs the smaller one m.

The second correlation detector 212 detects the actual scanning signals (the video signal S5 and the video signal S4 in FIG. 4 such as bc1 in the field Bc1 in FIG.
bc3) and the absolute value (| bc2-bc1 | and | bc2 of the inter-field difference between the pixel of the actual scanning signal in the field after one field (the video signal S6 in FIG. 4, for example, bc2 in the field Bc2 in FIG. 2). −bc3 |), and outputs the smaller one n.

The comparator 223 compares the minimum absolute values m and n from the first and second correlation detectors 211 and 212, respectively. m ≧ h · n (h is a constant, h> 1, for example, h =
In the case of 2) (when the current field has a stronger correlation with the field one field later than the field one field before), the switch 227 is switched to the a side.

N ≧ hm (where h is a constant, h> 1, for example, h = 2) (when the current field has a stronger correlation with the field one field before than the field one field after) Switch 227 is switched to the b side.

When m <hn and n <hm (that is, when the correlation value between the current field and the field immediately before the field is substantially equal to the correlation value between the current field and the field immediately before the field) ), The switch 227 is switched to the c side.

The motion detector 224 outputs an actual scan signal (ac2 in the field Ac2 in FIG. 2) of the field one field before the current field (for example, the field Bc1 in FIG. 2).
Absolute value (| ac2-bc2 |) of the difference between the pixel of the actual scanning signal (bc2 of the field Bc2 in FIG. 2) and the pixel of the field one field after the current field.
Is calculated, and the absolute value is compared with a predetermined threshold value. When the absolute value is equal to or larger than the threshold value, it is determined that there is a motion, and a motion detection pulse is output.

The flat portion detector 225 detects an actual scanning signal (for example, the field Bc in FIG. 2) adjacent above and below the current field.
1 (bc1, bc3), the absolute value of each pixel difference (| bt1
−bt3 |) is compared with a predetermined threshold value. If the threshold value is not more than the threshold value, it is determined to be flat in the vertical direction, and a flat portion detection pulse is output.

The AND circuit 226 receives the motion detection pulse and the flat portion detection pulse, detects a flat and moving point in the vertical direction, and outputs a detection pulse.

When m ≧ h · n (when the current field has a stronger correlation with the field after one field than the field before one field), the first counter 231
In the current field period, the number of detection pulses supplied from the AND circuit 226 is counted, and the integrated value (first integrated value K1) is output.

The second counter 232 determines that when n ≧ hm (when the current field has a stronger correlation with the field one field earlier than the field one field later)
During the current field period, the number of detection pulses supplied from AND circuit 226 is counted, and the integrated value (second integrated value K2) is output.

The third counter 233 counts the number of motion detection pulses in the current field period, and outputs an integrated value (third integrated value K3). The integrated values of the first to third counters 231 to 233 are reset for each field.

The determiner 241 calculates the first integrated value K1 and the second integrated value K1.
And the third integrated value K3 is compared with a predetermined threshold value, and K1 ≧ i · K2 (i is a constant,
If i> 1), it is determined that the current field is a film moving image (backward film moving image mode) having a strong correlation with the field after one field, and K2 ≧ i · K1 (i is a constant and i> In the case of 1), it is determined that the current field is a film moving image (front film moving image mode) having a strong correlation with the field one field before, and when the third integrated value K3 is equal to or more than a predetermined threshold value, K1 <i · K2 and K2
In the case of <i · K1, it is determined that the image is a general moving image (TV moving image mode), and when the first integrated value K1 is less than a predetermined threshold value, it is determined that the image is a still image (still image mode). Here, when determining that the image is a still image (still image mode), the determiner 241 maintains the mode state determined for the field one field before.

As described above, in the film mode detecting means 2 shown in FIG. 4, the film moving image mode (telecine conversion image) and the TV moving image mode (telecine-converted image) are shifted backward or forward for each field based on the correlation with the preceding and succeeding fields. General image) or still image mode. Accordingly, a field in which the 2-3 cyclic patterns are discontinuous, that is, a field in which the telecine-converted image is switched to an image that is not a telecine-converted image (an image in which the 2-3 cyclic pattern is broken) is immediately generated. Can be detected.

[0047]

As described above, the display device according to the present invention detects whether or not an input video signal is a video signal obtained by converting from a 24 Hz film source, and removes a duplicated field at the time of conversion. 24 Hz, and generates a 24 Hz progressive scanning video signal to drive the display panel, so that the display image can be displayed with the same number of frames as during projection, and a display image closer to the projection can be obtained. it can.

[Brief description of the drawings]

FIG. 1 is an overall block diagram of a display device according to the present invention.

FIG. 2 is a diagram for explaining an operation of converting an interlaced scanning video signal (NTSC signal) subjected to telecine conversion by a 2-3 pull-down method into a progressive scanning video signal.

FIG. 3 is a diagram illustrating a timing of writing a converted progressively scanned video signal (a) to a frame memory and a timing of reading from the frame memory.

FIG. 4 is a diagram showing another example of the configuration of the film mode detecting means of FIG. 1;

[Explanation of symbols]

 1... Progressive scan conversion means 2... Film mode detection means 3... Control means 4, 5... Frame memory 6, 7, 227. Control means 9 ··· Read control means 10 ··· Address driver 11 ··· Sustain driver 12 ··· Display panel (PDP) 201, 203 Field memory 202 Line memory 211, 212 ··· Correlation Detector 223... Comparator 224... Motion detector 225... Flat part detector 226... AND 231 to 233... Counter 241.

Claims (4)

[Claims] 1. A detecting means for detecting whether an input video signal is a 60-Hz field-based telecine-converted video signal obtained by performing a telecine conversion on a 24 Hz film source, and detecting the input video signal by a telecine converting means. Video signal processing means for removing a field duplicated at the time of the telecine conversion from the telecine-converted video signal to generate a video signal of a 24 Hz progressive scan when the converted video signal is detected, and the 24 Hz progressive scan A display panel driving means for driving the display panel with the video signal. 2. A progressive scan conversion means for converting an input interlaced scan video signal into a progressive scan video signal, wherein the input interlaced scan video signal is obtained by subjecting a 24 Hz film source to telecine conversion. Detecting means for detecting whether or not the received 60-Hz field-based telecine converted video signal; a frame memory; and controlling writing of the converted progressively scanned video signal to the frame memory and reading from the frame memory. Frame memory control means, and display panel driving means for driving a display panel with progressively scanned video signals read from the frame memory, wherein the detection means detects that the input video signal is a telecine-converted video signal. When detected, the progressive scan conversion means inter-field interpolation using fields of the same film frame. Sequentially generating a video signal having the scanning by the processing, the frame memory control means thins out the fields of the same pattern written into the frame memory, display device, characterized in that for reading out from the frame memory at 24 Hz. 3. When the detection means detects that the input video signal is not a telecine-converted video signal, the frame memory control means performs writing to the frame memory and reading from the frame memory at 60 Hz. The display device according to claim 2, wherein: 4. The display device according to claim 3, wherein said detecting means detects whether or not the signal is a telecine-converted video signal for each field based on a correlation with the preceding and following fields.