JP2940714B2 - Facsimile broadcast transmission system and reception system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facsimile broadcasting transmission system for multiplexing and transmitting a facsimile signal to a television broadcast.

[0002]

2. Description of the Related Art From the 1965's, terrestrial facsimile broadcasting systems in which fixed images such as characters, graphics, and photographs were transmitted using television broadcast waves and reproduced and recorded on the receiving side were studied. (Refer to February 1987, etc.) In February 1989, two systems, the analog system and the digital system, were reported to the Minister of Posts and Telecommunications.
issue). Of these, as shown in FIG.
Providing the second subcarrier newly to the frequency of 5f _H, the second
An image signal equivalent to that of a wired G3 facsimile is transmitted by subjecting the subcarrier to four-phase differential modulation. A digital facsimile signal is transmitted at a rate of 16 kbps with a frame having a configuration as shown in FIG. 9 as one unit. In FIG. 9, PFX (prefix) is DAT (data)
The DAT unit is used for identifying the unit, and is roughly divided into an image signal and a control signal. The receiver extracts the program selection signal by the PFX part of the facsimile signal transmitted in a time-series configuration as shown in FIG. (Communication technology 1989.
5).

As one of the transmission methods of the high-resolution image in such facsimile broadcasting, a method of dividing the high-resolution image information into a plurality of low-resolution image information parts, compressing the divided parts, and transmitting the divided parts in a time-division manner is conceivable. . In this method, a high-resolution image is represented by G1 to G4 according to the method shown in FIG.
, And each image is compressed and encoded and transmitted. After the receiving side restores each code data, G
1 to G4 are synthesized based on FIG. 6 to obtain a high-resolution image.

[0004]

However, according to this method, an image having the same data amount is transmitted four times, and the transmission and reception times are expected to be about four times as long as the case of low resolution.

In facsimile broadcasting, transmission errors are prevented because a signal is multiplexed on a television wave and transmitted. Therefore, when receiving and recording each image data which is transmitted by dividing a high resolution original into standard resolution parts. If a decoding error occurs, the restored images of each standard resolution cannot be aligned in the sub-scanning line direction, and when the restored images are combined, an image that is significantly different from the original image may occur.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a facsimile broadcasting transmission system for multiplexing a facsimile signal with an audio signal of a television broadcast and transmitting the multiplexed facsimile signal. Image dividing means for dividing one or more low-resolution interpolated images into one or more low-resolution interpolated images, MR one-dimensionally encoding one scan line of the low-resolution reference image, and then using the scan line as a reference line and using the interpolated image as MR2 A facsimile broadcast transmission system comprising compression encoding means for dimensionally encoding, and means for transmitting each of the compression-encoded image signals in a predetermined signal format, and a facsimile image transmitted by the system. In a facsimile broadcast receiving system for receiving a signal, decoding means for expanding a received image signal; A high-resolution original image is obtained by synthesizing a decompressed image of each scanning line using a scan line encoded according to the method as the low-resolution reference image and a scan line encoded according to the MR two-dimensional method as the low-resolution interpolation image. An object of the present invention is to solve the above-described problem by configuring a facsimile broadcast receiving system including an image restoring unit for restoring.

[0007]

According to the above means, the interpolated image is encoded by referring to the reference image and encoding based on the position of the changed pixel from the reference pixel.
The transmission information amount is compressed by the two-dimensional encoding, and transmission / reception efficiency is improved.

Further, at the time of decoding, since the images are transmitted in the order of the scanning lines, decoding is performed based on the MR one-dimensionally encoded scanning lines, that is, the reference image, and matching between the reference image and the interpolation image is performed. Can take.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

First, a facsimile broadcasting transmission system will be described. In FIG. 1, (1) is a high-resolution image input means, and a document to be transmitted is read into an image memory (not shown). This image information is stored as high-resolution image information shown in FIGS. 6 and 7 (a). The resolution of this image information is, for example, 3456 pixels / 215 mm in the main scanning direction.
± 1% and the sub-scanning direction is 15.4 lines / mm ± 1%.

(2) An image dividing circuit divides image information into four blocks as shown in FIG. 6 for each small block of a high-resolution image, for example, a block of 2 × 2 pixels. FIG. 7 shows only the pixel G1 extracted from the high-resolution image information shown in FIG.
As shown in FIG. 7C, the low-resolution reference image G1 as shown in FIG. 7B is taken out of the low-resolution reference image G1 and the low-resolution interpolation image G2 as shown in FIG. The image is divided into images G2 to G4. G1 to G4 can be received and recorded without processing by a standard receiver (for example, G3), and have a low resolution equivalent to a standard image (for example, 1728 pixels in the main scanning direction / 215 mm ± 1% 7.7 in the sub-scanning direction) / Mm ± 1%) and is stored in the divided image memories (3a to 3d).

(4) is an encoding circuit. The low resolution reference image G1 is obtained by MR one-dimensional encoding, the low resolution interpolation image G2 is obtained by MR two-dimensional encoding with reference to the G1 line, and G3 is hereinafter referred to as G2. G4 is compressed by MR two-dimensional encoding using G3 as a reference line, and is converted into facsimile code data. The facsimile code data is converted into a packet frame by a packet frame generation unit (5). An example of this packet framing will be described. In facsimile broadcasting, a frame composed of 32 packets is formed as shown in FIG.
Send by c. One frame contains data of each code sequence, and the PFX unit of FIG. 9 is used so that the contents of each packet can be identified. As an example of the PFX unit, a conventional image signal (b3 to b5 of B1 is 011) as shown in FIG.
Is assigned to the low-resolution image G1 (the conventional standard device can receive and record the low-resolution reference image G1 by assigning in this manner) to the newly defined interpolation image signal (B1
B3 to b5 are defined as interpolation images G2 to G4 and packetized.

An example of the packet configuration will be described with reference to FIG. First, the code data of the reference image G1 is
1 and b3 to b5 are set to “011”, and the interpolated image data G2 to G4 are subsequently converted to b3 to b4 of the PFX unit B1.
A packet is configured by setting b5 to “101”. At this time, if the last code bit of the reference image data or the interpolated image data sequence is not the last of the packet, the space between them is filled with fill bits (F). The data packet formed by the above procedure corresponds to the portion (m line) in FIG. 2A.
You. EOL + 1 is a signal obtained by adding bits "and" to a signal EOL indicating that the signal is at the end of the line. EOL + O
Is a signal obtained by adding the bit “0” to EOL. Also,
If all of the interpolated images G2 to G4 are the same image as the reference image G1, the interpolation image data is omitted as in the B portion (m + 1, m + 2 lines), and then the packet is transferred from the next reference image data in the same manner as the above means. (FIG. 2C). After forming such a packet, frames are assembled so that the facsimile code sequence of the image G1 satisfies the minimum scanning time of 10 ms / scanning line in frame unit which is a standard of facsimile broadcasting, thereby forming a facsimile image signal sequence. The television transmission section (6) multiplexes the television audio signal with the television audio signal and transmits it as a television broadcast.

Next, a receiving system for receiving and restoring an image transmitted from the transmitting system of FIG. 1 will be described with reference to FIG.

(8) a tuner for detecting a signal of a predetermined channel from a television broadcast wave received by an antenna (7) and extracting a facsimile signal, and (9) detecting a sound signal of the extracted channel. 8, a voice detection circuit for obtaining a spectrum signal as shown in FIG. 8, (10) a band-pass filter (BPF) for extracting only a facsimile signal from a spectrum signal as shown in FIG. 8, and (11) a digital modulation A demodulation circuit for a four-phase differential phase modulation signal, which demodulates the obtained facsimile signal to obtain a digital signal sequence, (12)
Is a descrambling process for restoring a signal that has been scrambled and interleaved in units of frames in FIG.
An interleave processing circuit (13) is an error correction circuit for correcting an error generated in the transmission circuit. By the signal processing from the tuner (8) to the error correction circuit (13), a facsimile signal in packet units shown in the upper part of FIG. 9 can be obtained. A packet identification / extraction circuit (14) identifies a program selection signal packet and an image signal packet from the digital signal sequence, and extracts only a DAT part from each packet. The extracted image signal is stored in the code buffer (15).

(16) A decoding circuit for expanding a compressed code sequence, which performs expansion as follows. This will be described with reference to FIG. First, when a high-resolution image transmitted according to the method of the present embodiment is received, an MR one-dimensionally encoded scan line, that is, an image of G1 is restored and stored in a low-resolution reference image line buffer (20a). , MR two-dimensionally encoded scanning lines, that is, G2 to G4, are decoded with reference to the decompressed images of G1 to G3, respectively, and stored in the low-resolution interpolation image line buffers (20b, 21a, 21b). When the above decoding is completed, the line synthesis circuit (22)
According to (b), line synthesis is performed, G1 and G2 are synthesized, and G3 and G4 are synthesized and transferred to the line memory B (23b). If no scan line encoded by MR is found, the decompressed image of G1 is copied to G2 to G4 and the above synthesis is performed.

The scanning lines of the high-resolution image obtained as described above are stored in the line memories A and B and then transferred to the image memory (17). The image memory (17) has a capacity enough to store one page of the high-resolution image A4 size, and when the decoding of one page is completed, the content is printed by the printing unit (18).

Next, in the case of receiving a low-resolution image transmitted by the conventional method, a facsimile signal is decoded, and the decompressed image is stored in (20a) and (20b).
Subsequently, (21a) and (21b) are duplicated in (20a) and (20b) and line synthesis is performed, and the resultant is transferred to the line memories A and B, respectively. Subsequently, the line memories A and B are each transferred twice to the image memory. That is, the pixel density in the main / sub-scanning line direction of the expanded image is converted into a pixel density equivalent to high resolution and stored in the image memory (17). The same applies to the printing section
If printing is performed in (18), the received image can be recorded.

Next, a description will be given of a line synthesizing process when a transmission error occurs during transmission of a high-resolution image according to the present embodiment. When decoding an MR-encoded facsimile signal, processing is performed with reference to an MR one-dimensional code line, that is, EOL + 1. This is because the two-dimensional encoding is based on the reference line and cannot be decoded if the reference line is different. That is, when an error occurs, the next EOL + 1 is searched, and the next decoding is started from that. In the present embodiment, G1 is MR one dimension, G2 to G
4 is MR two-dimensionally encoded. As described above, when an error occurs in the G1 code sequence, G2 to G4 cannot be decoded. Therefore, the image stored in the line memory A or B, which has been subjected to the extension line synthesis processing, is transferred to the image memory 17 again, and the previous line is replaced. Below G2
If an error occurs in the sequence, G1 is copied to G2 (G
2 is G1), and the combined line of G1 and G2 is G3 and G
By replacing the combined line of G3 and G4 with the combined line of G1 and G2 when an error occurs in the sequence of G3.
If an error occurs in the sequence of G4 by replacing the composite line with G4, error processing can be performed by copying G3 to G4. As described above, according to the method of this embodiment, even when a transmission error occurs, the matching of G1 to G4 is not disturbed.

Although the embodiment of the facsimile broadcast transmitting and receiving system according to the present invention has been described, the present invention is not limited to the above embodiment. For example, in FIG. 2, whether the DAT unit is the reference resolution data by the PFX unit,
Since it is possible to identify whether the data is interpolation image data, the EO is obtained by coding the reference image data using the MH coding method.
The L code can be reduced by one bit.

The present invention can also constitute a system for transmitting and receiving high-resolution image information in the same manner in facsimile broadcasting using a data channel of satellite broadcasting.

[0022]

According to the present invention, high-resolution image information can be transmitted and received efficiently, and even if a transmission error occurs, an image closer to the original image can be restored by decoding error correction.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a transmission system according to an embodiment of the present invention;

FIG. 2 is a diagram showing a packet configuration using a basic image and a complementary image.

FIG. 3 is a configuration diagram of a receiving system.

FIG. 4 is a detailed diagram of a decoding circuit part of FIG. 3;

FIG. 5 is a diagram illustrating an example of a bit definition of a PFX unit;

FIG. 6 is a schematic diagram of a high-resolution image showing a relation between a high-resolution image and a low-resolution image.

FIGS. 7A to 7E are schematic diagrams of image division.

FIG. 8 is a spectrum diagram showing channels of digital facsimile broadcasting.

FIG. 9 is a configuration diagram of a frame matrix of a facsimile signal.

FIG. 10 is a time-series configuration (time sequence) of a facsimile signal.

[Explanation of symbols]

 (2) Image dividing circuit (4) Encoding circuit (5) Packet / frame generating circuit (16) Decoding circuit (19) Decoding section (22) Line combining circuit.

Continued on the front page (72) Inventor Masaaki Hasegawa 2--18 Keihanhondori, Moriguchi-shi Sanyo Electric Co., Ltd. (72) Inventor Mika Tanaka 2-18 Keihanhondori, Moriguchi-shi Sanyo Electric Co., Ltd. (72) Invention Person Hiroshi Senoo 1-10-11 Kinuta, Setagaya-ku, Tokyo Japan Broadcasting Corporation Research Institute (72) Inventor Isamu Misono 1-10-11 Kinuta, Setagaya-ku, Tokyo Japan Broadcasting Corporation Research Institute (56) Reference Document JP-A-3-261232 (JP, A) JP-A-61-237580 (JP, A) JP-A-4-35464 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H04N 1/00 H04N 1/41-1/419 H04N 7/08-7/088

Claims (2)

(57) [Claims] 1. A facsimile broadcasting transmission system for multiplexing and transmitting a facsimile signal to a radio wave of a television broadcast and transmitting a high-resolution original image as a facsimile image to a low-resolution reference image and one or more low-resolution images for interpolating the same. Image dividing means for dividing into one or more interpolated images, and MR one-dimensionally encoding one scan line of the low-resolution reference image;
A facsimile broadcast transmission system comprising: compression encoding means for sequentially MR-two-dimensionally encoding the interpolated image using the scanning line as a reference line; and means for transmitting each compression-encoded image signal in a predetermined signal format. . 2. A facsimile broadcast receiving system for receiving a facsimile image signal transmitted by the facsimile broadcast transmission system according to claim 1, wherein decoding means for expanding the received image signal by MR decoding;
By combining a scan line decoded by the R1D method as the low-resolution reference image and a scan line decoded by the MR two-dimensional method as the low-resolution interpolation image, an expanded image of each scan line is synthesized to obtain a high-resolution image. A facsimile broadcast receiving system comprising: an image restoration unit for restoring an original image.