JPH09247669A - Image transmitter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain transmission of image with high performance without missing of an image frame by synchronizing an image frame frequency of an image input signal with an image frame frequency of an image output signal. SOLUTION: An image head position detection section 7 detects an image head position signal 8 corresponding to each image pattern from a video bit stream signal 6 of a digitized transmission moving image. Furthermore, an image number detection section 9 detects a transmission image number signal 10 corresponding to each image and a synchronization image display timing generating section 13 generates an outputs an image display timing signal 14 synchronously with the consecutive image number and the display timing signal is used to realize image transmission with high performance without missing in the moving image sent digitally.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image transmission device which is applied to an image transmission section between a video camera, a video tape reproducing device and the like and a monitor television or the like and which digitally transmits moving image information.

[0002]

2. Description of the Related Art FIG. 3 is a block diagram showing a configuration of a conventional image transmission device. In the figure, the video camera 1
An image input signal 4 having a cycle synchronized with the screen capture timing signal 3 generated by the built-in screen capture timing generation unit 2 is supplied to the image encoding unit 5. The image encoding unit 5 encodes the image input signal and outputs the video bitstream signal 6. The video bitstream signal 6 of the moving image that has been digitally encoded is decoded by the image decoding unit 15 and output to the screen display unit 17 as a decoded image signal 16. The independent screen display timing generation unit 20 independently generates the screen display timing signal 14 and outputs it to the image display unit 17. The image display unit 17 generates an image output signal 18 from the screen display timing signal 14 and the decoded image signal 16, and causes the monitor television 19 to display a moving image.

[0003]

In the conventional image transmission apparatus described above, as shown in FIG. 3, the image capture timing generation section 2 and the independent screen display timing generation section 20 are operated independently of each other. If the frequency of the screen capture timing signal 3 is higher than the frequency of the screen display timing signal 14, the moving image information in the video bit stream signal 6 transmitted from the image encoding unit 5 to the image decoding unit 15 is obtained. There is a problem that some of them are discarded without generating the image output signal 18, and the transmitted moving image is not properly displayed on the monitor TV 19.

The present invention solves the above-mentioned conventional problems, and synchronizes the image frame frequency of the image input signal with the image frame frequency of the image output signal to enable high-performance image transmission without image frame loss. It is an object of the present invention to provide an image transmission device according to the above.

[0005]

In order to achieve the above object, in the image transmission apparatus of the present invention, the head position corresponding to each screen is selected from the transmitted video bit stream signal of the moving image. A signal and a screen number signal are detected, and a synchronous type screen display timing generation unit generates and outputs a display timing signal synchronized with consecutive screen numbers. It enables high-performance image transmission without loss in transmitted moving images.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention is a screen head position for detecting a head position signal corresponding to each screen in a video bit stream signal of a transmitted digitized moving image. A detection unit, a screen number detection unit that detects a screen number signal corresponding to each screen in the video bit stream signal, and a synchronous screen display timing generation that generates and outputs a display timing signal synchronized with consecutive screen numbers. And a digital transmission of moving image information capable of synchronizing the image frame frequency of the input signal and the image frame frequency of the output signal by using the display timing signal,
High-performance image information is transmitted without loss in the transmitted moving image information.

According to a second aspect of the present invention, when a discontinuous screen number is detected by the screen number detecting section, it is interpolated to generate a continuous screen number signal, and the synchronous type It is equipped with a screen number interpolation unit that outputs to the screen display timing generation unit, and enables higher-performance image information transmission by enabling interpolation of missing in consecutive screen numbers. is there.

A preferred embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of the entire apparatus for explaining one embodiment of the present invention. The same members and signals as those described in FIG. Omit it.

In FIG. 1, the screen top position detecting section 7 is
The head position signal corresponding to each screen is detected from the video bit stream signal 6 to be described later, and the screen head position signal 8 is detected.
Further, the image number detector 9 generates a continuous transmission screen number signal 10 from the screen head position signal 8. When the screen number detecting unit 9 detects discontinuous screen numbers, the screen number interpolating unit 11 performs interpolation processing based on the transmission screen number signal 10 to generate continuous interpolating screen number signals 12. The synchronous screen display timing generation unit 13 is a screen display timing signal synchronized with the continuous interpolation screen number signal 12.
14 is generated and output to the screen display unit 17.

FIG. 2 is a structural diagram showing an example of a video bit stream signal, which is transmitted in order from the L1 side. L
1, L2, L3, ..., LN are information of N sequentially transmitted images, and the length of each bit may be the same value or different lengths. A1, A
2, A3, ..., AN are header information for indicating the position of the beginning of the screen, which is given for each image. ITU-T
Recommendation H. In the case of 261, it is a PSC (picture start code).

B1, B2, B3, ..., BN are each image 1
Information indicating the screen number given to each sheet
-T Recommendation H. In the case of 261, TR (temporal reference) is a transmission screen number given by the image encoding unit 5 to the image input signal synchronized with the screen capture timing signal 3 built in the video camera 1. In the transmission screen number, when the image encoding unit 5 encodes and transmits all the screens of the image input signal, the value is generally "1".
When the information of the fixed bit length, which is sequentially increased step by step, is used, and when the specific image of the image input signal is not encoded and transmitted by the image encoding unit 5, the corresponding screen number is generally omitted and increased. Information of fixed bit length is used. C1,
C2, C3, ..., CN are true coded information of the image to be transmitted, and the length of each bit may be the same value or different lengths.

In the present apparatus, the screen head position detector 7 selects the screen head position signal from the video bit stream signals 6.
(A1, A2, A3, ..., AN) 8 is detected, and the screen number detection unit 9 detects the screen top position signal (A1, A2, A3 ,.
..., AN) 8 as a reference, the transmission screen number signals (B1, B
2, B3, ..., BN) 10 are separated. Screen number interpolation section 1
1 is a transmission screen number signal (B1, B2, B3, ..., B
N) 10 to generate the interpolated screen number signal 12, and the synchronous screen display timing generation unit 13 generates the interpolated screen number signal 12.
A screen display timing signal 14 synchronized with 12 is generated and output to the screen display unit 17.

As a concrete example of the transmission screen number signal 10, for example, four discontinuous transmission screen number signals 10 in the order of M, M + 1, M + 3, M + 6 (M is an integer) are arranged on the video bit stream signal 6. It is transmitted and the screen number interpolator
When input to 11, M, M + 1, M + 2, M +
It is converted into seven consecutively interpolated screen number signals 12 of 3, M + 4, M + 5, M + 6, which are incremented by “1”, and output to the synchronous screen display timing generation unit 13.

Further, for example, M, M + 1, M + 2, M +
When four consecutive transmission screen number signals 10 in the order of 3 (M is an integer) are transmitted on the video bit stream signal 6 and input to the screen number interpolation unit 11, they are the same as the input values. 4 of M, M + 1, M + 2, and M + 3 are converted into the interpolated screen number signal 12 and output to the synchronous screen display timing generation unit 13.

The synchronous screen display timing generation unit 13
Is configured using a DPLL (Digital Phase Locked Loop) circuit, generates a stable screen display timing signal (vertical sync signal and horizontal sync signal) 14 in synchronization with the input interpolation screen number signal 12, and Display 17
Output to The screen display unit 17 generates an image output signal 18 based on the decoded image signal 16 decoded by the image decoding unit 15 and the screen display timing signal 14, and outputs the image output signal 18 to a monitor television 19 for image display. .

By doing so, the image frame frequency of the image input signal 4 and the image frame frequency of the image output signal 18 are synchronized, so that the video bit stream signal 6 is generated due to the difference in frequency as in the conventional case.
An image output signal is not generated for some of the moving image information, and there is no loss in the transmitted moving image information, and high-performance image display is performed.

Although an example in which the above apparatus is provided in the video camera 1 has been described, the present invention is also applicable to a video tape reproducing apparatus, a video disk reproducing apparatus, and a video moving image reproducing apparatus.

[0019]

As described above, according to the image transmitting apparatus of the present invention, all the screen information contained in the transmitted video bit stream signal can be displayed on the monitor television or the like without being discarded. Therefore, high-performance transmission can be realized without loss of digitally transmitted moving image information.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an entire apparatus for explaining an embodiment of the present invention.

FIG. 2 is a structural diagram showing an example of a video bitstream signal.

FIG. 3 is a block diagram showing a configuration of a conventional image transmission device.

[Explanation of symbols]

4 ... Image input signal, 5 ... Image coding unit, 6 ... Video bit stream signal, 7 ... Screen head position detection unit, 8
... screen top position signal, 9 ... screen number detection unit, 10 ... transmission screen number signal, 11 ... screen number interpolation unit, 12 ... interpolation screen number signal, 13 ... synchronous screen display timing generation unit, 14
… Screen display timing signal, 15… Image decoding unit, 16
... Decoded image signal, 17 ... Screen display part, 18 ... Image output signal.

Claims (2)

[Claims] 1. A screen head position detecting unit for detecting a head position signal corresponding to each screen in a video bit stream signal of a transmitted digitized moving image, and a screen head position detecting unit for each screen in the video bit stream signal. An image transmission apparatus comprising: a screen number detection unit that detects a corresponding screen number signal; and a synchronous screen display timing generation unit that generates and outputs a display timing signal synchronized with continuous screen numbers. 2. A screen number which, when a discontinuous screen number is detected by the screen number detecting unit, interpolates the discontinuous screen number to generate a continuous screen number signal and outputs it to the synchronous screen display timing generating unit. The image transmission device according to claim 1, further comprising an interpolation unit.