JPH02126782A - Still picture transmission equipment - Google Patents

Abstract

PURPOSE:To suppress costs by switching a high-picture-quality transmitting mode to a low-picture-quality transmitting mode according to a use, and transmitting a picture. CONSTITUTION:Transmission contents are stored through an A/D converter 10 to a memory 4 by a video rate write/read controller 9. At the beginning of the transmission, a mode change-over switch 7 is operated, a first MODEM 1 and a first write/read controller 3 are operated, and the contents are transmitted in the low-picture-quality transmitting mode. When the transmission mode of the other equipment can only correspond to the high-picture-quality transmission mode based on communication, however, the fact is detected by a controller 6, and the operation is automatically switched to a second MODEM 2 for the high-picture-quality transmission mode and a second write/read controller 5. Thereafter, when the transmission is executed in the high-picture-quality mode, the second MODEM 2 and the second write/read controller 5 are operated by the mode change-over switch 7, and the picture is transmitted.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a still image transmission device capable of switching transmission modes depending on image quality.

<Prior Art> In recent years, still image transmission devices that transmit images shot with a still video camera and recorded on a video floppy or the like using a telephone line and display the images on a television screen are becoming popular among businesses.

On the other hand, although it is a still image transmission device, a device for general households called a still image videophone has also been commercialized.
It is designed to be transmitted.

<Problem to be solved by the invention> By the way, the former (hereinafter referred to as still video) has a large number of pixels in accordance with the -IC television standard, and has a high horizontal resolution of about 400 to 500.64 to 256 gradations. Although it transmits high-quality color TV images, the transmission speed takes about 1 to 2 minutes.

On the other hand, the latter (hereinafter referred to as TV phone) has a small number of pixels and transmits relatively low-quality black and white images of 100 (vertical) x 96 (horizontal) and 32 gradations, but the transmission speed is 6 to 10 seconds. degree and fast.

As shown in item 2, standards for still video have high image quality but low transmission speed (and standards for TV telephone have low image quality but high transmission speed), each having their own advantages and disadvantages.

However, in the case of still video used in companies, it is often not necessary to always transmit high-quality images when communicating with the other party, but it is necessary to send high-quality images, and the transmission This was an unreasonable situation in that it took time to do so, and the cost of using telephone lines increased.

On the other hand, even in the case of home-use TV phones, it is likely that people will have to be satisfied with low image quality due to price, but it is highly likely that products with higher image quality will become available as prices fall in the future. In this case as well, there may be cases where low image quality transmission is sufficient, so there is a desire to have a low image quality transmission function as well.

The present invention has been made in view of these conventional problems, and an object of the present invention is to provide a still image transmission device that solves the above problems by having a configuration in which the transmission mode can be freely switched depending on the image quality.

Therefore, as shown in FIG. 1, the present invention provides a still image transmission device for transmitting still image video signals via a telephone line. and a mode switching means for switching the transmission mode means.

In addition, as shown by the chain line in Fig. 1, there is a mode detecting means for detecting the transmission mode of the other party, and a means for detecting the transmission mode of the other party when the detected transmission mode of the other party is single. A configuration may also be provided in which mode fixing means for fixing the mode is added.

For example, at the beginning of communication with the other party, when transmitting memos and images to be left behind for verification purposes, low image quality is sufficient.
In this case, the mode switching means selects and operates the low image quality transmission mode means.

Thereafter, when transmitting a high-quality image, the mode switching means selects and operates the high-quality transmission mode means.

Further, in a device equipped with a mode detection means and a mode fixing means, the transmission mode of the other party is detected from the data obtained through communication, and if the transmission mode is single, the mode fixing means adjusts the operation of the mode switching means. Regardless, a transmission mode means suitable for the transmission mode of the other party is selected and operated.

<Example> Embodiments of the present invention will be described below based on the drawings.

In FIG. 2 showing the configuration of an embodiment, the first MODEM
I is a modulator compatible with low image quality transmission mode for video telephones,
The second MODEM2 is a modulator compatible with a high-quality transmission mode for still video.

The first writing/continuation controller 3 reads the image data from the memory 4 at a speed corresponding to the low image quality transmission mode, and transmits the image data from the telephone line via the first MODEMI, or from the telephone line via the first MODEM1. It has a function of writing still image video signals into the memory 4.

The second write/continuation controller 5 reads the image data from the memory 4 at a speed corresponding to the high image quality transmission mode and transmits it from the telephone line via the second MODEM 2, or from the telephone line via the second MODEM 2. It has a function of writing the transmitted still image video signal into the memory 4.

The controller 6 is for controlling the overall operation, and sends control signals such as start and stop to the first MODEMI and the second MODEM2, and controls the first MODEMI and the second MODEM2.
DEMI and the second MODEM 2 input the results of communication with the other party (the type of the other party's transmission device, specifically the type and number of transmission modes, whether the other party is ready for transmission, etc.).

When using the low image quality transmission mode using the first MODEMI, the first writing/continuing controller 3 is used at the same time, and when using the high image quality transmission mode using the second MODEM 2, the second writing/continuing controller 3 is used. Control so that 5 are used at the same time.

Therefore, the first MODEMI, the first write/read controller 3, and the controller 6 constitute a low image quality transmission mode means, and the second MODEM 2, the second write/read controller 5, and the controller 6 constitute a high image quality transmission mode means. be done.

Further, when the mode changeover switch 7 as a mode changeover means is pressed, the transmission mode is changed over by the controller 6, and at this time, the mode display (blinking) by the mode display lamp 8 is also changed over, but depending on the above-mentioned communication result, When it is detected that the other party's transmission mode is compatible with only one mode, MODEM and the write/continuation controller are selected to use the same transmission mode as the other party's transmission mode regardless of switch operation. and operate it.

That is, the controller 6 also has the functions of mode detection means and mode fixing means.

Since the video rate writing/continuation controller 9 continues to display images on the display independently of the above operations,
Image data is read out from the memory 4 and outputted to the display from the output terminal OUT via the DA converter 11, and a still image video signal input via the input terminal IN from a video floppy or the like (not shown) is AD converted by the AD converter lO. It has a function of converting the data and writing it into the memory 4.

Next, a series of transmission operations by this device will be explained.

In the case of transmission, first, the transmission contents recorded on a video floppy or the like are stored in the memory 4 via the AD converter 10 by the video rate write/read controller 9.

Initially, when transmitting memos, etc., use a low-quality transmission mode,
- mode is sufficient, so the first MODEMI and the first write/continuation controller 3 are operated by pressing or pressing the mode changeover switch 7 to perform transmission in the low image quality transmission mode.

However, when the transmission mode of the other party's device can only support high image quality due to communication, this is detected by the controller 6, and the operation of the second MODEM 2 and the second writing/continuation controller 5 for the high image quality transmission mode is automatically adjusted. can be switched to

Thereafter, if transmission is to be performed in the high-quality mode, the second MODEM 2 and the second write/continuation controller 5 are operated by the mode changeover switch 7 to perform transmission in the high-quality transmission mode.

However, in this case as well, if the other party can only support low image quality, the controller 6 automatically switches to the low image quality mode and transmits the image.

On the other hand, when receiving, select the MODEM that matches the transmission mode of the other party.
and the write/continue controller are selected and temporarily stored in the memory 4, and the video rate write/continue controller 9 reads out the stored data and outputs it to the display via the DA converter 11 for reproduction and display.

<Effects of the Invention> As explained above, according to the present invention, transmission can be performed by switching between high image quality transmission mode and low image quality transmission mode depending on the purpose, and memory etc. can be shared. Costs can also be kept to a minimum.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of the present invention, and FIG. 2 is a block diagram showing the configuration of the present invention.
FIG. 1 is a circuit diagram showing the configuration of an embodiment of the present invention.

Claims (2)

[Claims] (1) In a still image transmission device that transmits still image video signals via a telephone line, a high image quality transmission mode means that transmits still image video signals with high image quality and a low image quality means that transmits still image video signals with low image quality. A still image transmission device comprising: a transmission mode means; and a mode switching means for switching the transmission mode means. (2) It includes a mode detection means for detecting the transmission mode of the other party, and a mode fixing means for fixing its own transmission mode to match the transmission mode of the other party when the detected transmission mode of the other party is single. The still image transmission device according to claim 1, characterized in that: