JP3603683B2 - Video encoder circuit and television system conversion method - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a video encoder circuit provided in, for example, a digital camera for converting an NTSC signal obtained by shooting into a PAL signal and outputting the PAL signal, and a television system conversion method used in the circuit.
[0002]
[Prior art]
FIG. 7 shows a circuit configuration of a general digital camera. In the figure, reference numeral 10 denotes a digital camera. The digital camera 10 can selectively set a recording mode and a reproduction mode. In the recording mode, a CCD 12 disposed behind the lens 11 and serving as an imaging device is provided with a timing generator (TG). 13. The scanning drive is performed by the vertical driver 14, and the photoelectric conversion output for one screen is output at regular intervals.
[0003]
The photoelectric conversion output is sampled and held by a sample and hold circuit (S / H) 15, converted into digital data by an A / D converter (A / D) 16, and subjected to color processing by a color processing unit 17. , A digital value luminance and color difference multiplex signal (YUV data) is generated and written into the DRAM 18 as a buffer memory.
[0004]
After writing the YUV data into the DRAM 18, the CPU 19 reads out at least a part of the YUV data from the DRAM 18 in accordance with a specific television system, for example, the number of effective scanning lines of the NTSC, and sends it to the video encoder 20. The video encoder 20 generates an analog video signal for external output based on the YUV data, generates an analog RGB signal, and sends it to the display processing unit 21.
[0005]
The display processing unit 21 generates a timing signal for driving a liquid crystal display (LCD) panel, and drives the LCD panel 22 to display using an RGB signal based on the timing signal. When the LCD panel 22 is in the recording mode, By functioning as a liquid crystal finder and performing display based on driving of the display processing unit 21, a monitor image based on image information taken in from the CCD 12 at that time is displayed.
[0006]
When the shutter key constituting the key input unit 23 is operated at a timing at which recording is desired to be performed while the image at that time is displayed on the LCD panel 22 in real time, a trigger signal is generated. .
[0007]
In response to the trigger signal, the CPU 19 stops the path from the CCD 12 to the DRAM 18 immediately after the writing of one screen of YUV data captured from the CCD 12 to the DRAM 18 at that point in time, and enters a state of recording and saving. Transition.
[0008]
In this recording and storage state, the CPU 19 reads out one frame of YUV data written in the DRAM 18 in units called basic blocks of 8 pixels × 8 pixels for each of Y, Cb, and Cr components. The image is written to a JPEG processing unit (JPEG circuit) 24 and subjected to processing such as ADCT (Adaptive Discrete Cosine Transform) and Huffman coding, which is an entropy coding method, and compressed into a file. Data is obtained, and the obtained image data file is read out from the JPEG circuit 24 and written into the flash memory 25 which is a nonvolatile memory.
[0009]
Then, with the compression processing of the YUV data for one frame into the image data file and the completion of the writing of all the image data files to the flash memory 25, the CPU 19 restarts the path from the CCD 12 to the DRAM 18 again.
[0010]
The key input unit 23 includes a recording / replay mode switching key for switching between a recording (REC) mode and a reproducing (PLAY) mode, an image selection key, and the like, in addition to the shutter key described above. The no signal is sent directly to the CPU 19.
[0011]
Further, in the reproduction mode, the CPU 19 stops the path from the CCD 12 to the DRAM 18, and in response to the operation of the image selection key or the like of the key input unit 23, the CPU 19 reads out the code data of one specific frame from the flash memory 25 and performs The data is written into the processing unit 24, and the JPEG processing unit 24 performs the decompression process in a process completely opposite to the compression process. The video encoder 20 generates an analog video signal for external output from the YUV signal obtained by the decompression processing, and generates an analog RGB signal and sends it to the display processing unit 21.
[0012]
The display processing unit 21 drives the display of the LCD panel 22 using the analog RGB signals, so that the selected image data file can be displayed and output on the LCD panel 22.
[0013]
Next, a detailed circuit configuration in the video encoder 20 for generating an analog video signal and RGB from a digital YUV signal will be described with reference to FIG.
[0014]
In the figure, for example, when 4: 2: 2 YUV data composed of an 8-bit (or 16-bit) parallel pixel data string in the CCIR656 format is input to the video encoder 20, the YUV data is converted into 4: After the same YUV data of 4: 4 is interpolated, it is output to the low-pass filters (LPF) 321 to 323 and the conversion circuit 33.
[0015]
The low-pass filters 321 to 323 selectively pass only the YUV frequency components, and their outputs are sent to an arithmetic circuit 34 including a plurality of adders and multipliers.
[0016]
The arithmetic circuit 34 converts the U and V signals into subcarrier signals (f_SC) The sub-carrier signals from the generator 36 are respectively modulated by the sine / cosine phases, and then added. The added signal is superimposed with the burst signal from the burst signal generator 37, and the horizontal synchronization signal oscillated by the synchronization signal generator 35. A video signal can be generated by further superimposing a Y signal on which a signal and a vertical synchronizing signal are superimposed. The video signal thus obtained is smoothed by a D / A converter 38 and converted into an analog video signal. Deriving outside.
[0017]
On the other hand, the conversion circuit 33 directly calculates RGB signals from a 4: 4: 4 YUV signal by a matrix operation, and converts the outputs thereof into analog signals by D / A converters 391 to 393, respectively. Will be output to
[0018]
The composite synchronization signal CSYNC and the reference clock are both input to the video timing signal generator 40, where various timing signals are generated and supplied to each circuit in the video encoder 20.
[0019]
[Problems to be solved by the invention]
By the way, the video signal and the RGB signal created as described above are both created according to a predetermined television system, for example, in Japan, the number of scanning lines of the NTSC system, the output timing of the signal, and the like.
[0020]
Therefore, it is not possible to cope with a television system different from the television system of the created signal, for example, an external output device or a liquid crystal display panel that operates in a PAL system, and as a result, an external device that outputs a video signal or an RGB signal It is necessary to prepare a dedicated video encoder 20 that conforms to the television system of the liquid crystal display panel that displays.
[0021]
Therefore, for example, in order to enable a digital camera to be used in a foreign country having a different television system, a plurality of circuits having the configuration shown in FIG. 8 are prepared according to the number of television systems, and one of them is provided. This means that the circuit is selected and used, and the circuit scale becomes very large.
[0022]
SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a video encoder circuit capable of supporting a plurality of television systems with a smaller circuit scale and a television used in the circuit. It is another object of the present invention to provide a method for converting a video format into a video format.
[0023]
[Means for Solving the Problems]
According to the first aspect of the present invention, in order to make the signal of the first television system an effective number of scanning lines of the signal of the second television system, the first television system and the second television system are effective. One line data constituting the YUV signal is superimposed for every predetermined number according to the ratio of the number of scanning lines.4: 2: 2 or 4: 2: 0Input means for inputting a YUV signal, delay means for delaying the YUV signal input from the input means by one scanning line period and outputting the same, and inputting the YUV signal delayed by the delay means and the input means and Line conversion means for converting line data constituting the YUV signal by performing a line addition operation with the YUV signal not delayed by the delay means;First conversion means for converting the 4: 2: 2 or 4: 2: 0 YUV signal converted by the line conversion means into the 4: 4: 4 same signal;It is characterized by having.
The invention according to claim 2 isIn the invention according to claim 1, a second conversion means for converting the 4: 4: 4 YUV signal converted by the first conversion means into a video signal different from the YUV signal and the RGB signal, 4: 4: 4 converted by the first conversion meansNo. to convert YUV signal to RGB signal3And a conversion means.
[0024]
With such a configuration, after the YUV signal of the first television system is created from the image signal, the YUV signal of the first television system is simply converted to the number of effective scanning lines of the second television system. Since the converted YUV signal is input and converted from the YUV signal to the same signal of the second television system with high accuracy, it is possible to support a plurality of television systems with a smaller circuit scale.
[0025]
Furthermore, since the YUV signal of the first television system in which the chrominance component is omitted is converted into the same signal of the second television system, and then the chrominance component is interpolated, the conversion of the television system is particularly performed. It is possible to cope with a plurality of television systems while reducing the circuit scale required for the above.
According to the third aspect of the present invention, in order to make the signal of the first television system an effective number of scanning lines of the signal of the second television system, the first television system and the second television system have an effective number of scanning lines. Input means for inputting a YUV signal in which one line data constituting the YUV signal is superimposed for every predetermined number according to the ratio of the number of scanning lines, and delaying the YUV signal inputted from the input means by one scanning line period A delay means for outputting a YUV signal, and a line data constituting a YUV signal by performing a line addition operation on the YUV signal delayed by the delay means and the YUV signal inputted from the input means and not delayed by the delay means. , A first conversion means for converting a YUV signal inputted from the input means and not converted by the line conversion means into an RGB signal, Characterized in that the output of the duplicate lines in RGB signal obtained by the conversion means is provided with a line suppression means to prohibit.
[0026]
With such a configuration,After generating a YUV signal of the first television system from the image signal, a YUV signal having the number of effective scanning lines of the second television system simply converted from the YUV signal of the first television system is input. Since the YUV signal is converted into the same signal of the second television system with high accuracy, it is possible to support a plurality of television systems with a smaller circuit scale.
Furthermore, since the YUV signal of the first television system is obtained from the image signal and then further converted from the YUV signal to the same signal of the second television system, a plurality of television systems with a smaller circuit scale can be obtained. The output of the corresponding video signal becomes possible, and the YUV signals of both the first and second television systems can be obtained.
[0027]
The invention according to claim 4 isThe invention according to claim 3, further comprising second conversion means for converting the YUV signal converted by the line conversion means into a video signal different from the YUV signal and the RGB signal. .
[0028]
With such a configuration,According to the fourth aspect of the present invention, in addition to the effect of the third aspect of the invention, in addition to the effect of the third aspect of the present invention, a highly accurate YUV signal of the second television system is used. A video signal different from the YUV signal and the RGB signal can be obtained.
[0029]
The invention according to claim 5 isThe third conversion means for converting the 4: 2: 2 or 4: 2: 0 YUV signal input from the input means into the 4: 4: 4 same signal. Further, the delay unit delays the YUV signal converted by the third conversion unit by one scanning line period and outputs the YUV signal, and the line conversion unit compares the YUV signal delayed by the delay unit with the YUV signal. The line data forming the YUV signal is converted by performing a line addition operation with the YUV signal which has been converted by the conversion means of No. 3 and not delayed by the delay means, and the first conversion means performs the third conversion. The YUV signal converted by the means and not converted by the line conversion means is converted into an RGB signal.
[0030]
With such a configuration,In addition to the effect of the third or fourth aspect of the present invention, the present invention is particularly suitable for performing display or the like using RGB signals of the first television system.
[0031]
The invention according to claim 6 isIn the invention according to claim 4, a third conversion means for converting the 4: 2: 2 or 4: 2: 0 YUV signal converted by the line conversion means into the 4: 4: 4 same signal, A fourth conversion unit that converts a 4: 2: 2 or 4: 2: 0 YUV signal input from the input unit and not converted by the line conversion unit to a 4: 4: 4 YUV signal; The first converter converts the YUV signal converted by the fourth converter into a video signal, and the second converter converts the YUV signal converted by the third converter into an RGB signal. It is characterized in that it is converted into a signal.
[0032]
With such a configuration,In addition to the effect of the fourth aspect of the present invention, it is particularly suitable for performing display and the like using RGB signals of the first television system.
[0037]
Claim7According to the invention described above, the first television system and the second television system are used in order to make the YUV signal given in correspondence with the number of effective scanning lines of the first television system the effective number of scanning lines of the second television system. A line number converting step of superimposing one line for every predetermined number in accordance with the ratio of the number of effective scanning lines of the television system, and a delay step of delaying and outputting the YUV signal obtained in the line number converting step for one scanning line period. A line conversion step of converting line data constituting the YUV signal by performing a line addition operation on the YUV signal delayed in the delay step and the YUV signal obtained in the line number conversion step.Converting the 4: 2: 2 or 4: 2: 0 YUV signal obtained in this line conversion step into the 4: 4: 4 same signal.It is characterized by having.
[0038]
According to such a method, a YUV signal of the first television system is obtained from the image signal, and the YUV signal is simply converted so as to have an effective number of scanning lines of the second television system. Since the signal is converted into the same signal of the second television system with higher accuracy, it is possible to support a plurality of television systems with a smaller circuit scale.
[0039]
Furthermore, since the YUV signal of the first television system in which the chrominance component is omitted is converted into the same signal of the second television system, and then the chrominance component is interpolated, the conversion of the television system is particularly performed. It is possible to cope with a plurality of television systems while reducing the circuit scale required for the above.
In the invention according to claim 8, the YTV signal provided in correspondence with the number of effective scanning lines of the first television system is set as the number of effective scanning lines of the second television system. And a line number conversion step of superimposing one line for every predetermined number of lines according to the ratio of the number of effective scanning lines of the second television system, and outputting the YUV signal obtained in the line number conversion step for one scanning line period. A delay step; a line conversion step of converting line data constituting the YUV signal by performing a line addition operation on the YUV signal delayed in the delay step and the YUV signal obtained in the line number conversion step; A line suppressing step of prohibiting the output of the overlapping line of the YUV signal obtained in the converting step.
[0040]
With this method,A YTV signal of the first television system is obtained from the image signal, and the YUV signal is simply converted to have the number of effective scanning lines of the second television system. Since the signal is converted into the same signal of the television system, it is possible to support a plurality of television systems with a smaller circuit scale.
Furthermore, since the YUV signal of the first television system is obtained from the image signal and then further converted from the YUV signal to the same signal of the second television system, a plurality of television systems with a smaller circuit scale can be obtained. The output of the corresponding video signal becomes possible, and the YUV signals of both the first and second television systems can be obtained.
[0041]
BEST MODE FOR CARRYING OUT THE INVENTION
(First Embodiment)
Hereinafter, a first embodiment in which the present invention is applied to a video encoder used in a digital camera will be described with reference to the drawings.
[0042]
The configuration of the digital camera itself is the same as that shown in FIG. 7, and the same portions are denoted by the same reference numerals, and the illustration and description thereof are omitted here.
[0043]
Here, the NTSC system is used as the first television system, and the PAL system is used as the second television system. From the NTSC system YUV signal having 240 effective scanning lines, the PAL system YUV having 288 effective scanning lines is used. A case where a signal is generated will be described.
[0044]
FIG. 1 shows a circuit configuration of the video encoder 50. Since the basic processing circuit flow is the same as that shown in FIG. 8, the same portions are denoted by the same reference numerals and description thereof will be omitted. It shall be.
[0045]
Then, the CPU 19 converts the YUV data read from the DRAM 18 into a YUV signal according to the NTSC system into a YUV signal according to the simplified PAL system by overlapping, for example, the first one of the five lines every five lines. The interpolation circuit 31 generates a 4: 4: 4 YUV signal by interpolating the color difference signals U and V in the input 4: 2: 2 YUV signal. Output to the one-line memory 51 and the line conversion circuit 52.
[0046]
The one-line memory 51 is composed of, for example, a RAM, and stores a YUV signal sent from the interpolation circuit 31 for one scanning line period in accordance with a timing signal from a video timing signal generation section 53, reads out the read-out YUV signal, and reads out the line conversion circuit 52. , Functions as a delay circuit for the YUV signal.
[0047]
In the line conversion circuit 52, a YUV signal directly input from the interpolation circuit 31 and a YUV signal delayed and input via the one-line memory 51 are selected in line units according to a timing signal from the video timing signal generation unit 53. Then, by performing a line addition operation as appropriate, the simple PAL-system YUV signal is converted into an accurate (highly accurate) PAL-system YUV signal and output. 323 and the conversion circuit 33.
[0048]
The video timing signal generator 53 for inputting the composite synchronization signal CSYNC and the reference clock generates a timing signal to the one-line memory 51 and the line conversion circuit 52, and outputs the signals from the D / A converters 391 to 393. An enable signal EN-N corresponding to an effective scanning line period is generated and output to, for example, a drive circuit of a TFT liquid crystal display panel which displays an RGB signal.
[0049]
The operation of the one-line memory 51 and the line conversion circuit 52 having the above-described circuit configuration will be described with reference to FIGS.
[0050]
FIG. 2 shows a process when an accurate PAL system signal is generated from a simplified PAL system YUV signal.
[0051]
FIG. 2A shows the YUV signal output from the interpolation circuit 31 in units of scanning lines. In this case, the number of effective scanning lines 240 in the NTSC system and the number 288 of effective scanning lines in the PAL system are exactly 5: 6. Here, the YUV signal read out from the DRAM 18 as a buffer memory by the CPU 19 and input to the interpolation circuit 31 where the color difference components are interpolated and output to the one-line memory 51 and the line conversion circuit 52 here. Is converted into a simple PAL system in which, for example, one leading scanning line is overlapped for every five scanning lines to provide two scanning lines.
[0052]
Therefore, assuming that each scanning line is “L (Line) 1”, “L2”, “L3”} as shown in the figure, the YUV signal output from the interpolation circuit 31 to the one-line memory 51 and the line conversion circuit 52 is “L1 ”“ L1 ”“ L2 ”“ L3 ”“ L4 ”“ L5 ”“ L6 ”“ L6 ”“ L7 ”}.
[0053]
As shown in FIG. 2 (2), the one-line memory 51 stores the YUV signal from the interpolation circuit 31 in accordance with the timing signal from the video timing signal generation unit 53, and reads out the YUV signal so as to read one scanning line period. The data is transmitted to the line conversion circuit 52 after being delayed by an amount.
[0054]
The line conversion circuit 52 performs a line addition operation on the YUV signal of the current line directly sent from the interpolation circuit 31 and the YUV signal of the previous line sent from the one-line memory 51, as shown in FIG. Then, an accurate PAL YUV signal “P (Pal line) 1” “P2” “P3” “P4” “P5” “P6” “P7” “P8”} is calculated.
[0055]
FIG. 3 shows a specific example of the line addition operation performed by the line conversion circuit 52. In this way, extremely natural continuous 288 YUV signals are calculated from YUV signals of 240 effective scanning lines. Can be.
[0056]
The PAL YUV signal is converted to a video signal by the low-pass filters 321 to 323 and the arithmetic circuit 34 and then converted to an analog signal by the D / A converter 38 and output to the outside. After being converted into analog signals by the D / A converters 391 to 393, the signals are supplied to the drive circuit to be displayed.
[0057]
The video timing signal generator 53 generates an enable signal EN-N which becomes "L" level during the period of 288 effective scanning lines in response to the PAL YUV signal output from the line conversion circuit 52. Then, the data is output to the drive circuit of the TFT liquid crystal display panel to be displayed.
[0058]
As described above, only by using the DRAM 18 which is an existing buffer memory, there is no need to provide an image buffer memory inside and outside the video encoder 50 when converting from the NTSC system to the PAL system. It is possible to convert the YUV signal from the NTSC system as the first television system to the PAL system as the second television system while keeping the scale.
[0059]
When it is desired to obtain a video signal and an RGB signal of the NTSC system instead of the PAL system, the CPU 19 reads the YUV signal from the DRAM 18 which is a buffer memory at the previous stage of the video encoder 50 and inputs the signal to the interpolation circuit 31. Even in the video encoder 50, the line conversion circuit 52 is directly sent from the interpolation circuit 31 without performing the operation of converting to the simple PAL system, in which one scanning line is input for every five scanning lines. Only the incoming YUV signal is passed through and output without conversion.
[0060]
At this time, the video timing signal generator 53 converts the timing signal supplied to each circuit in the video encoder 50 including the line conversion circuit 52 and the enable signal EN-N into a display timing of the NTSC system instead of the PAL system. It shall be based on.
[0061]
In the above-described embodiment, the one-line memory 51 is described as being constituted by a RAM, but is not limited thereto, and may be constituted by, for example, a shift register.
[0062]
The interpolation circuit 31 interpolates the color difference signals U and V to obtain the same number of scanning lines (horizontal pixels) as the luminance signal Y, and then supplies the same to the one-line memory 51 and the line conversion circuit 52. As shown in (1), the 4: 2: 2 YUV signal may be processed by the one-line memory 51 and the line conversion circuit 52 and then interpolated by the interpolation circuit 31 to be converted to the 4: 4: 4 YUV signal.
[0063]
In this case, the one-line memory 51 and the line conversion circuit 52 only need to execute the processing in a state where the color difference signals U and V are halved, so that the circuit scale of the entire video encoder 50 is larger than that of the circuit of FIG. Can be reduced.
[0064]
Note that, in the above-described embodiment, a description has been given assuming that the first scanning line is input in duplicate for every five NTSC YUV signals having 240 effective scanning lines, but the present invention is not limited to this. The second or subsequent scanning lines in the book may be overlapped.
[0065]
(Second embodiment)
Hereinafter, a second embodiment in which the present invention is applied to a video encoder used in a digital camera will be described with reference to the drawings.
[0066]
The configuration of the digital camera itself is the same as that shown in FIG. 7, and the same portions are denoted by the same reference numerals, and the illustration and description thereof are omitted here.
[0067]
Here, the NTSC system is used as the first television system, and the PAL system is used as the second television system. From the NTSC system YUV signal having 240 effective scanning lines, the PAL system YUV having 288 effective scanning lines is used. A case where a signal is generated will be described.
[0068]
FIG. 5 shows a circuit configuration of the video encoder 60. Since the basic processing circuit flow is the same as that shown in FIG. 1, the same portions are denoted by the same reference numerals and description thereof will be omitted. Shall be.
[0069]
Thus, the YUV signal output from the interpolation circuit 31 is output to the one-line memory 51, the line conversion circuit 52, and the conversion circuit 33, and the YUV signal converted by the line conversion circuit 52 into an accurate PAL method is output to the low-pass filters 321 to 323. Shall be supplied only to
[0070]
That is, when the D / A converter 38 wants to externally output the video signal converted to the PAL system, the YUV signal input from the CPU 19 to the interpolation circuit 31 is converted to the NTSC system as shown in FIG. This is a simple PAL system in which one is superimposed for every five.
[0071]
However, focusing only on the RGB signals output from the D / A converters 391 to 393, the liquid crystal display panel to be displayed is configured such that the number of electrodes in the vertical direction corresponding to the number of scanning lines matches the NTSC system. Therefore, when displaying PAL RGB signals, thinning must be performed on a line-by-line basis as a generally used technique, and a discontinuous image will be displayed as it is.
[0072]
Therefore, the video timing signal generator 53 'generates an enable signal LOE for enabling other than the superimposed lines in synchronization with the simple PAL YUV signal, and outputs the enable signal LOE to the LCD timing signal generator 61.
[0073]
The LCD timing signal generating section 61 generates a liquid crystal drive signal as an operation clock in phase synchronization with the enable signal LOE, and together with the RGB signals output from the D / A converters 391 to 393, the liquid crystal display to be displayed. Supply to the drive circuit of the panel.
[0074]
In such a circuit configuration, the liquid crystal display panel is driven by the RGB signal based on the original NTSC YUV signal while the simple PAL YUV signal is input from the CPU 19 to the interpolation circuit 31. Can be.
[0075]
At the same time, the LCD timing signal generator 61 is operated in synchronization with the enable signal LOE output from the video timing signal generator 53 'to supply an operation clock to the liquid crystal display panel. No circuit or the like is required, and the circuit scale of the entire digital camera including the video encoder 60 can be further reduced.
[0076]
In the above embodiment, the interpolation circuit 31 interpolates the color difference signals U and V with respect to the 4: 2: 2 YUV signal to obtain a 4: 4: 4 signal, and then the one-line memory 51, Although it is supplied to the line conversion circuit 52 and the conversion circuit 33, as shown in FIG. 6, it is divided into a video signal processing system and an RGB signal processing system, and the video signal processing system has a 4: 2: 2 processing system. The YUV signal is first processed by the one-line memory 51 and the line conversion circuit 52 and then interpolated by the interpolation circuit 31 to be converted into a 4: 4: 4 YUV signal, while the RGB signal processing system uses 4: 2: The second YUV signal may be interpolated by an interpolation circuit 62 having the same configuration as the interpolation circuit 31 and supplied to the conversion circuit 33.
[0077]
In this case, although two interpolation circuits 31 and 62 having the same configuration must be provided, the one-line memory 51 and the line conversion circuit 52 execute the processing in a state where the color difference signals U and V are halved. For this reason, the circuit scale of the video encoder 60 as a whole can be further reduced as compared with the configuration of FIG.
[0078]
In each of the first and second embodiments, only the case where the NTSC system YUV signal is converted into the PAL system signal has been described. However, the present invention is not limited to this. The number of scanning lines can be converted according to the ratio between the first television system and the second television system having different numbers.
[0079]
Similarly, the conversion process of the television system is not limited to the video encoder circuit of the digital (still) camera, but can be applied to a liquid crystal television device, a digital video camera, and the like, which are assumed to be used for portable use. .
[0080]
In addition, the present invention can be variously modified and implemented without departing from the gist thereof.
[0081]
【The invention's effect】
According to the first and second aspects of the present invention, after the YUV signal of the first television system is created from the image signal, the YUV signal of the first television system is simply converted into an effective signal of the second television system. A YUV signal having the number of scanning lines is input, and the YUV signal is converted into the same signal of the second television system with high accuracy. Therefore, it is possible to support a plurality of television systems with a smaller circuit scale. It becomes.
Furthermore, since the YUV signal of the first television system in which the chrominance component is omitted is converted into the same signal of the second television system, and then the chrominance component is interpolated, the conversion of the television system is particularly performed. It is possible to cope with a plurality of television systems while reducing the circuit scale required for the above.
[0082]
According to the invention described in claim 3,After generating a YUV signal of the first television system from the image signal, a YUV signal having the number of effective scanning lines of the second television system simply converted from the YUV signal of the first television system is input. Since the YUV signal is converted into the same signal of the second television system with high accuracy, it is possible to support a plurality of television systems with a smaller circuit scale.
Furthermore, since the YUV signal of the first television system is obtained from the image signal and then further converted from the YUV signal to the same signal of the second television system, a plurality of television systems with a smaller circuit scale can be obtained. The output of the corresponding video signal becomes possible, and the YUV signals of both the first and second television systems can be obtained.
[0083]
According to the invention of claim 4, in addition to the effect of the invention of claim 3,From the highly accurate YUV signal of the second television system, a video signal different from the YUV signal and the RGB signal can be obtained.
[0084]
According to the invention described in claim 5,In addition to the effects of the third or fourth aspect of the present invention, the present invention is particularly suitable for performing display or the like using RGB signals of the first television system.
[0085]
According to the invention described in claim 6,In addition to the effect of the fourth aspect of the present invention, it is particularly suitable for performing display and the like using RGB signals of the first television system.
[0088]
Claim7According to the invention described above, a YTV signal of the first television system is obtained from the image signal, and the YUV signal is simply converted so as to have an effective number of scanning lines of the second television system. Since the signal is converted into the same signal of the second television system with high accuracy, it is possible to support a plurality of television systems with a smaller circuit scale.
Furthermore, since the YUV signal of the first television system in which the chrominance component is omitted is converted into the same signal of the second television system, and then the chrominance component is interpolated, the conversion of the television system is particularly performed. It is possible to cope with a plurality of television systems while reducing the circuit scale required for the above.
[0089]
Claim8According to the described invention,After generating a YUV signal of the first television system from the image signal, a YUV signal having the number of effective scanning lines of the second television system simply converted from the YUV signal of the first television system is input. Since the YUV signal is converted into the same signal of the second television system with high accuracy, it is possible to support a plurality of television systems with a smaller circuit scale.
Furthermore, since the YUV signal of the first television system is obtained from the image signal and then further converted from the YUV signal to the same signal of the second television system, a plurality of television systems with a smaller circuit scale can be obtained. The output of the corresponding video signal becomes possible, and the YUV signals of both the first and second television systems can be obtained.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a circuit configuration of a video encoder according to a first embodiment of the present invention.
FIG. 2 is an exemplary view for explaining conversion to a PAL system according to the embodiment;
FIG. 3 is an exemplary view showing an example of specific calculation contents of a line addition operation according to the embodiment;
FIG. 4 is an exemplary block diagram showing another circuit configuration of the video encoder according to the embodiment;
FIG. 5 is a block diagram showing a circuit configuration of a video encoder according to a second embodiment of the present invention.
FIG. 6 is an exemplary block diagram showing another circuit configuration of the video encoder according to the embodiment;
FIG. 7 is a block diagram showing a circuit configuration of a general digital camera.
FIG. 8 is a block diagram showing a circuit configuration in the video encoder of FIG. 7;
[Explanation of symbols]
10. Digital camera
11 ... Lens
12 ... CCD
13. Timing generator
14. Vertical driver
15 ... Sample hold circuit
16 A / D converter
17 color processing unit
18 ... DRAM
19 ... CPU
20 Video encoder
21 Display processing unit
22 LCD panel
23 key input section
24 ... JPEG processing unit
25 ... Flash memory
31 ... (4: 2: 2 → 4: 4: 4) interpolation circuit
321-323 ... Low-pass filter
33 ... Conversion circuit
34 ... (YUV → RGB) arithmetic circuit
35: Synchronous signal generator
36 ... Subcarrier signal generator
37 ... burst signal generator
38,391-393 ... D / A converter
40 video timing signal generator
50 ... Video encoder
51 ... 1 line memory
52 ... Line conversion circuit
53, 53 '... video timing signal generator
60 Video encoder
61 LCD timing signal generator
62 ... (4: 2: 2 → 4: 4: 4) interpolation circuit

Claims (8)

In order to make the signal of the first television system the number of effective scanning lines of the signal of the second television system, the ratio of the number of effective scanning lines of the first television system to that of the second television system is determined. Input means for inputting a 4: 2: 2 or 4: 2: 0 YUV signal in which one line data constituting the YUV signal is superimposed for every predetermined number of lines;
Delay means for delaying the YUV signal input from the input means by one scanning line period and outputting the result;
Line conversion means for converting line data constituting the YUV signal by performing a line addition operation on the YUV signal delayed by the delay means and the YUV signal input from the input means and not delayed by the delay means ;
A first conversion means for converting the 4: 2: 2 or 4: 2: 0 YUV signal converted by the line conversion means into the same 4: 4: 4 signal is provided. Video encoder circuit. A second converter for converting the 4: 4: 4 YUV signal converted by the first converter into a video signal different from the YUV signal and the RGB signal;
3. The video encoder circuit according to claim 1, further comprising: third conversion means for converting the 4: 4: 4 YUV signal converted by the first conversion means into an RGB signal. In order to make the signal of the first television system the number of effective scanning lines of the signal of the second television system, the ratio of the number of effective scanning lines of the first television system to that of the second television system is determined. Input means for inputting a YUV signal in which one line data constituting the YUV signal is superimposed for every predetermined number
Delay means for delaying the YUV signal input from the input means by one scanning line period and outputting the result;
Line conversion means for converting line data constituting the YUV signal by performing a line addition operation on the YUV signal delayed by the delay means and the YUV signal input from the input means and not delayed by the delay means;
First conversion means for converting a YUV signal input from the input means and not converted by the line conversion means into an RGB signal;
Line suppressing means for inhibiting output of overlapping lines in the RGB signal obtained by the first converting means;
A video encoder circuit comprising: 4. The video encoder circuit according to claim 3, further comprising a second conversion unit configured to convert the YUV signal converted by the line conversion unit into a video signal different from the YUV signal and the RGB signal. A third conversion unit for converting the 4: 2: 2 or 4: 2: 0 YUV signal input from the input unit into the 4: 4: 4 YUV signal;
The delay means delays the YUV signal converted by the third conversion means by one scanning line period and outputs the signal.
The line conversion unit performs a line addition operation on the YUV signal delayed by the delay unit and the YUV signal converted by the third conversion unit and not delayed by the delay unit, thereby forming a line forming a YUV signal. Transform the data,
The first converter converts the YUV signal converted by the third converter and not converted by the line converter into an RGB signal.
5. The video encoder circuit according to claim 3, wherein: Third conversion means for converting the 4: 2: 2 or 4: 2: 0 YUV signal converted by the line conversion means into the 4: 4: 4 YUV signal;
A fourth conversion unit that converts a 4: 2: 2 or 4: 2: 0 YUV signal input from the input unit and not converted by the line conversion unit to a 4: 4: 4 YUV signal; ,
The first converter converts the YUV signal converted by the fourth converter into a video signal,
The second converter converts the YUV signal converted by the third converter into an RGB signal.
5. The video encoder circuit according to claim 4, wherein: In order to make the YUV signal provided corresponding to the number of effective scanning lines of the first television system the effective number of scanning lines of the second television system, the YUV signal of the first television system and the second television system are used. A line number conversion step of superimposing one line for every predetermined number in accordance with the ratio of the number of effective scanning lines;
A delay step of delaying and outputting the YUV signal obtained in the line number conversion step by one scanning line period;
A line conversion step of converting line data constituting the YUV signal by performing a line addition operation on the YUV signal delayed in the delay step and the YUV signal obtained in the line number conversion step ;
A conversion step of converting the 4: 2: 2 or 4: 2: 0 YUV signal obtained in the line conversion step into the same 4: 4: 4 signal. Method conversion method. In order to make the YUV signal given in correspondence with the number of effective scanning lines of the first television system the number of effective scanning lines of the second television system, the YUV signal of the first television system and the second television system are used. A line number converting step of superimposing one line for every predetermined number in accordance with the ratio of the number of effective scanning lines;
A delay step of delaying and outputting the YUV signal obtained in the line number conversion step by one scanning line period;
A line conversion step of converting line data constituting the YUV signal by performing a line addition operation on the YUV signal delayed in the delay step and the YUV signal obtained in the line number conversion step;
A line suppressing step for inhibiting output of overlapping lines of the YUV signal obtained in the line number converting step;
A television system conversion method comprising:

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