JP2953526B2 - Transmission method of facsimile broadcasting - Google Patents

Description

The present invention relates to a method of transmitting a facsimile broadcast in which a facsimile signal is multiplexed and transmitted to a television broadcast.

B) Conventional technology A facsimile broadcasting system that transmits fixed images such as text, graphics, and photographs using television broadcast waves and reproduces and records them on the receiving side has been studied since the 1970s (The Journal of the Institute of Television Engineers, 1987). In February 1989, two systems, the analog system and the digital system, were reported to the Minister of Posts and Telecommunications (Telecommunications Technology Council Report Consultation No. 15).

Among these, the digital facsimile signal is transmitted at a rate of 16 kbps with a frame having a configuration as shown in FIG. 4 as one unit. In Figure 4, PFX (prefix) is DAT
The DAT section is used to identify a (data) section, and is roughly divided into an image signal and a control signal. The receiver receives the PFX of the facsimile signal sent in a time-series configuration as shown in FIG.
The program selection signal is extracted by the section, and the desired program can be selectively received by referring to the program number, page number, and the like included in the signal (see Communication Technology 1989.5).

Conventional facsimile transmission originals have a resolution of 1728 pixels / 215 mm ± 1% in the main scanning direction and a scanning line density of 7.7 lines / mm ± 1.
%, And a minimum scanning time of 10 ms / scanning line is guaranteed for each frame. In wired facsimile communication, a high-resolution original (with a resolution of 34 in the main scanning direction).
56 pixels / 215mm ± 1%, scanning line density 15.4 lines / mm ± 1%)
Is transmitted, the image signal is generally compressed by the MMR coding method and transmitted. Further, the transmitter determines the resolution or encoding method of the transmitted document according to the capability of the receiver.

C) Problems to be Solved by the Invention Facsimile broadcasting uses MMR coding, which has a higher transmission error rate than a cable system and does not allow 1-bit errors, because it multiplexes and transmits signals to television waves. Cannot be transformed. In addition, since transmission cannot be performed in accordance with the capability of the receiver, when high-resolution transmission is performed, reception cannot be performed by a receiver that does not have the capability, so that it is necessary to further transmit at standard resolution.

INDUSTRIAL APPLICABILITY The present invention enables reception and recording of high-resolution image information (original), regardless of whether the receiver has a high-resolution reception capability or a standard-resolution receiver, and improves transmission efficiency. The purpose is to let them.

D) Means for Solving the Problems The present invention divides high-resolution image information into a plurality of low-resolution image information when transmitting high-resolution image information in facsimile broadcasting, and compresses the divided image portion. Each divided part is transmitted in a time division manner.

E) Operation According to the above-described means, reception recording is performed by synthesizing a plurality of divided portions that have been restored in a high-resolution compatible receiver, and restoring one of the divided portions in a standard-resolution compatible receiver. be able to.

F) Embodiment An embodiment of the present invention will be described below with reference to the drawings. The facsimile broadcast transmission method of the present invention includes a step of decomposing high-resolution image information obtained from a document to be transmitted into a plurality of low-resolution image information; a step of compressing each divided portion obtained by dividing; It includes a step of time-divisionally transmitting a portion, and is realized by, for example, a transmission device having a configuration as shown in FIG. 1 (a).

That is, first, a document to be transmitted in the high-resolution image input unit (1) is read by a high-resolution scanner (not shown) or the like, and is stored in an image memory (not shown) in FIG.
It is stored as high-resolution image information shown in FIG. The resolution of this image information is, for example, 3456 pixels / 215 in the main scanning direction.
mm ± 1%, and the sub-scanning direction is 15.4 lines / mm ± 1%.

Next, in the image dividing unit (2), the image information is divided into small blocks of high-resolution image information, for example, blocks of 2 × 2 pixels, for example, divided into four. From the high resolution image information shown in FIG. 1B, only the GI pixels are extracted, and the low resolution divided image GI as shown in FIG. 2B is extracted from the G II pixels only, as shown in FIG. 2C. The high-resolution image information is divided into the divided images GI, G II, G II, such as the divided image G II.
Divide into I and G IV respectively. Each divided image has a low resolution corresponding to a standard image that can be received and recorded without being processed by a standard resolution receiver (for example, the main scanning direction is 1728 pixels / 215 mm ± 1).
%, The vertical scanning direction is 7.7 lines / mm ±%), and is stored in a divided image memory (not shown).

Next, each of the image parts GI to GIV is encoded (3a) to (3d).
Is converted into facsimile code data compressed by MH or MR coding. It should be noted that the divided image memory may be stored in the memory of the encoding unit after the encoding is performed while being divided without providing the divided image memory in the division unit (2) by using the encoding units (3a) to (3d) in common.

This facsimile coded data is converted into a packet frame by a packet frame generator (4). An example of this packet framing will be described. In the facsimile broadcast, as shown in FIG. 4, a signal composed of 32 packets as one frame is transmitted in frame units at about every 577 ms. Then, each divided image portion GI to GIV is allocated to one frame in a time-division manner by eight packets. Note that it is optional whether the packet arrangement is such that eight packets are collected for each part, or the parts I to IV and I to IV are sequentially and repeatedly transmitted. Then, an undefined portion of the PFX section of FIG. 4 is used so that each packet can be identified as an image obtained by dividing high-resolution image information. As an example of this PFX, a conventional image signal b3 to b5 is set to 011 as an image GI (image to be received and recorded by the standard resolution receiver), and as shown in the column of the interpolated image signal in FIG. Using 101, b6 is A, b7 is B, A = 0, B = 0 when the image G II, A = 0, B = 1 when the image
G III, A = 1, B, = 1 is defined as an image G IV. And then
After assembling the packet shown in FIG. 4, the frame shown in FIG. 4 is assembled to form a facsimile image signal sequence, which is multiplexed with a television audio signal by a television transmitting unit, and multiplexed with a video signal before being transmitted. In the above description, the facsimile code length of each image portion is naturally different, and thus the end point of the code data varies in each portion. Therefore, it is free to use the packet position used by the part that ended earlier earlier. For example, it may be used for another part or may be used as a blank signal.

By transmitting the facsimile codes of the divided images mixedly in each frame as in the above embodiment (FIG. 6 (c)), the divided images GI to GIV are serially transmitted one screen (one page) at a time. More effective transmission is possible than in the case (FIG. 6 (b)). That is, for example, considering the case where all the white lines are continuous, in order to guarantee the minimum scanning time of 10 ms / scanning line in the frame unit described above, only data of a maximum of 57 scanning lines exist in one frame. Can not.
When compressed by MR coding (K = 4), the codes of four scanning lines are as follows.

Since the code length is 72 bits long, it is about 1000 bits long for 57 scanning lines. Image information in one frame is 32
× 22 × 8 = 5632 bits, so the remaining 46
32 bits are invalid. However, according to this method, since each divided image portion in one frame is composed of eight packets, the code length is 8 × 22 × 8 = 1408 bits. Therefore, in the case of this method, the invalidity is 408 bits for each divided image portion, and 408 × 4 = 16 for one frame.
It is 32 bits long. From this, the divided images GI to G
It can be said that it is more efficient than sending the IVs one by one serially.

Also, the transmission efficiency is better than in the case where a high-resolution original is transmitted separately from a high-resolution program and a standard-resolution program (FIG. 6A). In other words, for high-resolution programs, the original image information amount is the same as that of this method, and in consideration of compression efficiency, the amount of transmitted data is generally smaller than that of this method, but the amount of data is large because the standard-resolution program is transmitted separately. Become. In addition, as shown in FIG. 5, a period of 6 frames is required between programs. Therefore, considering the whole, FIG. 6 (c)
It can be considered that the occupation time for the high-resolution program is shorter in the method of (1). Thus, high-resolution image information can be transmitted efficiently.

Further, on the receiving side, when the device is compatible with low (standard) resolution, only the GI of the facsimile image information is extracted based on the identification information of the PFX, decoded, and recorded. In the case of high resolution, the divided images GI to GIV can be decoded and then combined to restore and record a high resolution image signal.

In the above embodiment, the resolution of the high-resolution original in the main scanning direction is 3456 pixels / 215 mm ± 1%, and the scanning line density is 15.4.
The number is set to book / mm ± 1%, but is not limited to this. For example, if a high-resolution original is
When dividing into a standard resolution of 28 pixels / 215 mm ± 1% and a scanning line density of 15.4 lines / mm ± 1%, it is sufficient to divide into two in the sub-scanning direction. Although the number of packets of each part in one frame is set to 8 packets, the number of packets allocated to each part may be variable in consideration of the minimum scanning line time.

G) Effects of the Invention According to the present invention, it is possible to receive and record high-resolution image information at high resolution in a receiver supporting high resolution in facsimile broadcasting and at low resolution in a low-resolution receiver. large.

[Brief description of the drawings]

FIG. 1 (a) is a system configuration diagram for realizing the method of the present invention, FIG. 1 (b) is a diagram showing an example of dividing a high-resolution document of the present invention into a standard resolution, and FIGS. e) is a diagram showing a specific example of image division according to one embodiment of the present invention, FIG. 3 is a diagram showing bit definitions of a PFX section according to one embodiment of the present invention, FIG. 4 is a configuration diagram of a frame matrix of a facsimile signal, FIG. 5 is a diagram showing a time-series configuration (time sequence) of a facsimile signal, and FIGS. 6 (a), (b) and (c) are diagrams showing transmission examples of different high-resolution image information. (2) ... image division unit, (3a) to (3B) ... coding,
(4)... Packet frame generation unit.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI H04N 7/081 (72) Inventor Masayuki Sano 2--18 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Invention Person Mika Tanaka 2-18 Keihanhondori, Moriguchi-shi, Osaka Examiner, Sanyo Electric Co., Ltd. Mitsutake Fujiuchi (56) References JP-A-60-148279 (JP, A) (58) Fields investigated (Int. . ^6, DB name) H04H 1/00 H04N 1/00 H04N 7/08 H04J 3/00

Claims (2)

(57) [Claims] In a facsimile broadcasting transmission method for transmitting a facsimile signal by multiplexing a facsimile signal with a television broadcast signal, a step of dividing high-resolution image information into a plurality of low-resolution image information portions, and compressing each of the divided portions. Transmitting a plurality of compressed divided portions in a time-division manner. 2. A facsimile broadcast transmission method according to claim 1, wherein the facsimile code of each divided portion is mixed and transmitted in a frame of the image signal.