JPS63203070A - Video circuit - Google Patents

Abstract

PURPOSE:To display a picture data at a normal attitude even by a video software formed while being turned by 90 deg. by writing a digital picture data of a video signal into a memory and making the order of write different from the order of read from the memory by 90 deg.. CONSTITUTION:An input video signal is separated into a luminance signal and a chrominance signal by a video processing circuit 4, converted into a time series serial signal by a multiplexer 5, digitized and written in a buffer memory 7. A picture data read from the memory 7 is written in an odd number field memory 9 by a field switching circuit 8. In this case, the signal is written longitudinally from the right to the left. In case of reading a signal from the memory 9, it is read sequentially from a direction different from the write direction by 90 deg., that is, from the left to the right and from the upper to the lower direction. Thus, in case of inputting a BCG signal obtained from a field switching circuit 11, D/A converters 12-14 and a matrix 15 to the CRT, a pattern turned right by 90 deg. is reproduced. The processing above is applied entirely similarly as to an even number of fields.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image circuit in which the display mode of the screen is rotated by 90 degrees.

[Prior art]

A conventional television receiver or monitor has a horizontally long display screen with an aspect ratio of 4:4. However, the camcorder (
When using a camera-integrated VCR), video software created by rotating the camera 90 degrees will result in an image lying on its side.
When playing back a small television receiver, it is possible to change the landscape orientation to portrait orientation, but this is not possible with a large television receiver.

[Purpose of the invention]

An object of the present invention is to enable an image rotated by 90 degrees to be reduced and displayed on a screen, so that even video software created by rotating the image by 90 degrees as described above can be displayed in a normal posture.

[Structure of the invention]

For this purpose, in the present invention, image data obtained by A/D converting a video signal is once written into a memory, and the order of reading from the memory is made 90 degrees different from the order of writing.

〔Example〕

Examples of the present invention will be described below. FIG. 1 is a block diagram of a video circuit according to one embodiment. 1 is N
An input terminal 2 to which a TC3 system composite video signal is input is a synchronization processing circuit that extracts a synchronization signal from the composite video signal and sends it to a control circuit 3 that controls the entire circuit. 4 is a video processing circuit in which Y/C separation is performed, that is, a luminance signal and a color signal are separated. The luminance signal Y, color difference signals R-Y, B-Y obtained there are sent to the multiplexer 5.
and is converted into a serial time-series signal. and,
This serial signal is converted into a digital signal by an A/D/conversion circuit 6 and then written into a buffer memory 7. This buffer memory 7 consists of two line memories, and when one is in the write mode, the other is in the continuous write mode. The data of the luminance signal and color difference signal temporarily written here is written into the field memory 9 or 10 by the field switching circuit 8. This field memory 9.1
When one of the zeros is in the write mode, the other is in the read mode, and is selected and output by the field switching circuit 11, and the luminance signal and color difference signal data are individually transferred to the D/input switch 12.
~14 is converted into an analog signal and sent to the matrix circuit 15
The primary color signals are converted into RGB signals and then output.

Now, for example, if we look at the odd field, the original image data is sent in the order of the 1st line, 3rd line, ..., 2n+1th line, as shown in Figure 2. The A/D converter 6 sequentially converts the signals into digital signals. During this A/D/conversion, the sampling frequency is set to fsc(
If you select approximately 2.5 times the subcarrier), the sampling point on one scanning line will have an effective horizontal scanning rate of 0.835 in the NTSC system.
In this case, it will be 475 points. Also, set the vertical scanning rate to 0.
In the case of 945, the effective number of scanning lines is 496 in total. In other words, the number of sampling points in the horizontal direction is close to the number of scanning lines.

Then, the image data that has become digital data as described above is written to one line memory of the buffer memory 7, and during this writing, the image data of the previous line that has already been written to the other line is read out. The field switching circuit 8 writes the data into the field memory 9 of the odd field.

Writing at this time is performed vertically from the right to the left, as shown in FIG. 3, where the memory map is imitated on the display screen. Therefore, the data of the original screen (interlaced) is written in the left half at a position rotated by 90 degrees. Successive entries in the field memory 9 are read from a direction 90 degrees different from the direction of the writing order. That is, they are read out sequentially from left to right in FIG. 2, from top to bottom. Therefore, the RGB obtained via the field switching circuit 11, the D/A converters 12 to 14, and the matrix 15
If the signal is input to a CRT (not shown), a screen rotated 90 degrees to the right will be reproduced. In this case, the reproduced image is displayed on the left half of the screen according to the aspect ratio of the original image (
If this is done, a margin A will remain on the left as shown in Figure 3, but other data can be displayed here. The above is exactly the same for even fields.

Note that if the data is written in the field memory 9.10 sequentially from bottom to top and from left to right as shown in Figure 4, an image rotated 90 degrees to the left will be output from the CRT, contrary to the case in Figure 2. It will now be played.

In addition, in the above, the writing order to the field memory was performed in such an order that the screen was rotated 90 degrees, but the writing order is performed from left to right, top to bottom, and successive entries are performed by rotating the screen 90 degrees. You can also do that. That is, in this field memory, the writing order and the successive writing order may be made to differ by 90 degrees in the screen reproduction state. Further, although digital processing is performed at the luminance signal and color difference signal stages in the above example, it is also possible to perform matrix processing to convert the signals into RGB signals and then process them in the same manner. Further, although the configuration is made in field units in the above example, it can also be configured in frame units.

〔Effect of the invention〕

As described above, according to the present invention, since the screen of input image information can be rotated 90 degrees and displayed, the camcorder can be rotated 90 degrees.
Video software obtained by rotating the CRT screen can be played back in its normal position on the right or left side of the CRT screen. Furthermore, in this case, the remaining part of the screen rotated 90 degrees becomes a blank space, so other information can be displayed in that part.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram of the video circuit of the present invention, Fig. 2 is an explanatory diagram of the screen of the original image, Fig. 3 is an explanatory diagram of writing image data to the field memory, and Fig. 3 is an illustration of writing image data in another example. FIG.

Claims (1)

[Claims] (1) A video circuit characterized in that image data obtained by A/D converting a video signal is once written into a memory, and the order of reading from the memory is made 90 degrees different from the order of writing.