JPH0619384U - Video signal processing circuit - Google Patents

Abstract

(57) [Abstract] [Purpose] Miniaturize equipment and improve signal S / N. [Structure] The composite video signal aa is transferred to Y via the AD converter 1.
Luminance signal 2a and color signal 2 obtained by supplying to the / C separation circuit 2
b is supplied to a first recording luminance signal processing circuit 51 and a first recording color signal processing circuit 61 which perform digital signal processing,
These output signals are supplied to the second recording luminance signal processing circuit 52 and the second recording color signal processing circuit 62 via the first and second DA converters 3 and 4, where analog signal processing is performed. In addition, the luminance signal 2a and the color signal 2b are supplied to the TV via the third and fourth DA converters 7 and 8, and the numbers 1 to 4,
A video signal processing circuit characterized in that the configuration of 7, 8, 51, 61 is built in a one-chip IC.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a video signal digital processing circuit.

[0002]

[Prior art]

 In recent years, in a video signal magnetic recording / reproducing apparatus (hereinafter abbreviated as "VTR"), digital signal processing is performed in order to improve interference between both signals generated when a composite image signal is separated into a luminance signal and a color signal. The signal separation method used is being adopted.

The main part of the signal processing of the VTR using such a signal separation method will be described with reference to FIG. 3A with reference to each IC of one chip, and a composite video signal a from a transmission line (not shown) will be described. a is supplied to a Y / C separation circuit 2 for separating a luminance signal and a color signal via an AD converter 1. The luminance signal 2a and the color signal 2b, which have been subjected to digital signal processing, are transmitted from the VTR to a television receiver (hereinafter abbreviated as "TV") via the first and second DA converters 3 and 4. And a recording luminance signal processing circuit 5 for supplying well-known recording luminance signal processing such as pre-emphasis and FM modulation using analog processing, and crosstalk interference from an adjacent track during reproduction is improved. The recording color signal processing circuit 6 performs the PS and PI processing for this purpose and the known recording color signal processing such as high frequency conversion. The recording luminance signal 5a and the recording color signal 6a output from both circuits are supplied to a known recording / reproducing system (not shown).

[0004]

[Problems to be solved by the device]

 As described above, in the signal processing of the VTR, the configuration of the latter stage of the first and second DA converters 3 and 4 is performed by analog signal processing. However, there is a case where it is desired to newly process a part of the recording luminance signal processing circuit 5 and the recording color signal processing circuit 6 by using digital signal processing. In such a case, in order to supply the luminance signal and the color signal as monitor signals to the TV, it is necessary to newly provide a DA converter. Such a case will be described with reference to FIG. 3B by assigning a reference numeral to each IC of one chip. The same components as those in FIG. 7A are designated by the same reference numerals and the description thereof is omitted.

Here, the first and second recording brightness signal processing circuits 51 and 52 are in the recording brightness signal processing circuit 5, and the first and second recording color signal processing circuits 61 and 62 are the recording color signal processing circuits. Each corresponds to 6. Further, the first recording luminance signal processing circuit 51 and the first recording color signal processing circuit 61 are processing units that perform processing such as pre-emphasis and signal delay related to digital signal processing, and the remaining processing units. Corresponds to the second recording luminance signal processing circuit 52 and the second recording color signal processing circuit 62. Then, in order to supply the monitor signal to the TV, the luminance signal 2a and the color signal 2b are output from the VTR via the third and fourth DA converters 7 and 8.

In such signal processing, since the third and fourth DA converters 7 and 8 for securing the monitor signal are indispensable configurations, digital signals are respectively transferred between the ICs as compared with the conventional one. The number of transmission paths through which the transmission is performed increases. That is, it is a portion shown by a thick line in FIG. Since 8-bit parallel transmission or the like is used in such a transmission path, it is necessary to form a large number of wirings having a high frequency component on the substrate, which makes it difficult to miniaturize the device. Further, since a digital signal having a high frequency component (for example, sampled by 4 times subcarrier) is transmitted to these wirings, this digital signal is transmitted through the substrate or the air to The recording luminance signal processing circuit 52 and the second recording color signal processing circuit 62 of No. 2 jumped into the analog processing section as an interfering wave and deteriorated the S / N of the signal or caused a malfunction.

[0007]

[Means for Solving the Problems]

 The present invention provides the following configurations in order to solve the problems described above.

In a video signal processing circuit used in a video signal magnetic recording / reproducing apparatus, an AD converter for AD-converting an input video signal, and an output signal of the AD converter is subjected to digital signal processing to obtain a luminance signal and a color signal. Y / C separation circuit for separating and outputting, recording to the luminance signal, first recording luminance signal processing circuit for processing a part of the luminance signal processing using digital signal processing, and first recording luminance signal processing circuit And a first DA converter for converting the output signal of the D.A.D.A. to D.A., a first recording color signal processing circuit for processing a part of the recording color signal processing on the color signal using digital signal processing, A second DA converter for DA converting the output signal of the recording color signal processing circuit, a third DA converter for DA converting the luminance signal, and a fourth DA converter for DA converting the color signal, It remains in the output signal of the first DA converter. A second recording luminance signal processing circuit for processing the remaining recording luminance signal processing by using analog signal processing, and the remaining recording color signal processing for the output signal of the second DA converter by using analog signal processing. A second recording chrominance signal processing circuit for processing by means of the above, and the AD converter, the first to fourth DA converters, the Y / C separation circuit, the first recording luminance signal processing circuit, and the A video signal processing circuit, wherein the first recording color signal processing circuit is built in a one-chip integrated circuit.

[0009]

【Example】

 FIG. 1 is a block diagram for explaining a video signal processing circuit according to an embodiment of the present invention, and FIG. 2 is a block diagram for explaining a video signal processing circuit according to another embodiment. Hereinafter, embodiments will be described with reference to the drawings. The portion surrounded by the dotted line in both figures is composed of a one-chip IC circuit, and the same components as those in FIG. 3 are designated by the same reference numerals and the description thereof will be omitted.

1A is different from FIG. 3B in that the Y / C separation circuit 2, the first recording luminance signal processing circuit 51, and the first recording color signal processing circuit 61 are It is composed of AA which is the IC of the chip.

Therefore, no wiring is required for signal transmission between the Y / C separation circuit 2 and the first recording luminance signal processing circuit 51 and the first recording color signal processing circuit 61. Further, between the AD converter 1 and the Y / C separation circuit 2, between the Y / C separation circuit 2 and the third and fourth DA converters 7 and 8, and between the first recording luminance signal processing circuit 51 and A part of the wiring between the second AD converter 3 and between the first recording color signal processing circuit 61 and the fourth AD converter 4 can be formed inside AA. The upper wiring can be omitted.

As a result, the wiring for digital signals on the substrate is significantly reduced, and the device can be downsized. Further, it is possible to improve the mixing of the interfering wave from the wiring related to the digital signal on the substrate to the analog processing section such as the second recording brightness signal processing circuit 52 and the second recording color signal processing circuit 62.

Further, in FIG. 1B, since the AD converter 1 and the first to fourth DA converters 3, 4, 7 and 8 are also configured inside the AA, wiring related to digital signals on the substrate Can be eliminated, and downsizing of equipment and mixing of interfering waves can be further improved.

As described above, the case where a part of the recording luminance signal processing and the recording color signal processing is digitally processed has been described. However, a part of either the recording luminance signal processing or the recording color signal processing is digitally processed. The present invention can also be applied to signal processing, which will be described with reference to FIG.

FIG. 1A shows a case where a part of the recording luminance signal processing is digital signal processing and the recording color signal processing is an analog signal processing, and FIG. 1B shows a part of the recording color signal processing. This is a case where digital signal processing and recording luminance signal processing are analog signal processing. In both cases, the processing unit related to the digital signal processing exists only inside the AA, so that the miniaturization of the device and the mixing of the interfering wave can be improved as in the case described above.

[0016]

[Effect of device]

 As described above, according to the configuration of the present invention, the AD converter, the first to fourth DA converters, the Y / C separation circuit, the first recording luminance signal processing circuit, and the first recording color signal processing circuit are provided. Since it is built in a one-chip integrated circuit, it is possible to reduce the wiring related to digital signal transmission, so that there is an effect that the device can be downsized. In addition, it is possible to prevent the generation of interfering waves mixed in the second recording luminance signal processing circuit and the second recording color signal processing circuit related to the analog signal processing, thereby improving the S / N of the analog signal and preventing malfunction. There is an effect that can be prevented. Furthermore, with the integration of circuits, there are effects such as improved reliability and cost reduction.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating a video signal processing circuit according to an embodiment of the present invention.

FIG. 2 is a block diagram for explaining a video signal processing circuit of another embodiment.

FIG. 3 is a block diagram for explaining problems to be solved by a conventional video signal processing circuit and a new video signal processing circuit.

[Explanation of symbols]

 1 AD converter 2 Y / C separation circuit 2a Luminance signal 2b Color signal 3 First DA converter 4 Second DA converter 7 Third DA converter 8 Fourth DA converter 51 First recording brightness Signal processing circuit 52 Second recording luminance signal processing circuit 62 Second recording color signal processing circuit 61 First recording color signal processing circuit AA IC (Integrated circuit)

Claims (1)

[Scope of utility model registration request] 1. A video signal processing circuit used in a video signal magnetic recording / reproducing apparatus, wherein an AD converter for AD-converting an input video signal, and a luminance signal and a color signal by digital signal processing an output signal of the AD converter. And a Y / C separation circuit for separating and outputting the same, a first recording brightness signal processing circuit for processing a part of the recording brightness signal processing on the brightness signal using digital signal processing, and the first recording brightness signal processing A first DA converter for DA converting the output signal of the circuit; a first recording color signal processing circuit for processing a part of the recording color signal processing on the color signal using digital signal processing; A second DA converter for DA converting the output signal of the recording color signal processing circuit; a third DA converter for DA converting the luminance signal; and a fourth DA converter for DA converting the color signal, It remains in the output signal of the first DA converter. A second recording luminance signal processing circuit for processing the recording luminance signal processing of No. 2 by using analog signal processing, and the remaining recording color signal processing for the output signal of the second DA converter using analog signal processing A second recording color signal processing circuit, the AD converter, the first to fourth DA converters, the Y / C separation circuit, the first recording luminance signal processing circuit, and the first recording. A video signal processing circuit, characterized in that the color signal processing circuit is built in a one-chip integrated circuit.