JPH02112385A - Encoder - Google Patents

Abstract

PURPOSE:To prevent a terminal from executing erroneous recognition even when the conventional an encoder is switched in the middle of the encoding and output of a G3 FAX signal by delaying the switching timing of a switch in correspondence to the processing delay of the two types of the encoders. CONSTITUTION:Analog signals inputted from an input terminals 1 are inputted respectively to the two types of G3 FAX encoders 2, for which a processing time is different, a multi-pulse encoder 3, and a switch changeover control circuit 6. When switching information is received, the switch changeover control circuit 6 delays the switching timing by a switching timing delay circuit 7 in correspondence to the processing time of the encoders 2 and 3. Thus, since the encoding signal of a multi-pulse is not outputted even when the switching is executed in the middle of the encoding and output of the G3 FAX signal, a G3 FAX terminal in a reception side does not execute the erroneous recognition. In a CODEC limiting a transmission object only to a voice, a data signal can be also transmitted.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a speech encoding device, and in particular, the present invention relates to a speech encoding device, and in particular, the present invention is directed to a speech encoding device, in which two types of encoders having different encoding processing times are switched in a time-sharing manner, and one of the encoders is The present invention relates to an encoding device using.

[Conventional technology]

Conventionally, encoding devices with two types of encoders perform identification based on the identification information (for example, 1.1 kHz and 2.1 kHz sine wave tones in G3 7'7) of the input analog signal. The encoder was switched when information was detected.

FIG. 3 shows an example of fax signal transmission as an example of such a conventional encoding device. This encoding device has two types of encoders with different encoding processing times: a G3 fax signal encoder 12 whose encoding processing time is about IN seconds, and a G3 fax signal encoder 12 whose encoding processing time is about 60 milliseconds. a certain multi-pulse encoder 13;
The encoder includes a switch 14 for switching the digital output of 2.13, and a switch switching control circuit 16 for controlling which encoder the switch 14 selects. In the figure, 11 is an input terminal, and 15 is an output terminal.

[Problem to be solved by the invention]

However, in conventional encoding devices, if encoders with different encoding processing times are switched at the timing described above, the encoder will be switched in the middle of the analog output signal of the opposing decoder, resulting in a loss of encoding accuracy. In the case of a bad encoder, there is a drawback that the output analog signal of the decoder is not correctly received by the opposing terminal.

FIG. 4 is a timing diagram of the encoding device of FIG. 3;
(a) is from the switch switching control circuit 16 to the switch 1.
(b) shows the switch switching signal input to output terminal 1 (“L” selects 03 fax encoder 12).
(c) shows the decoded output waveform of the opposing decoder.

The time required for G3 fax encoding processing is approximately 10 milliseconds, while the time required for multipulse encoding processing is approximately 60 milliseconds. Perform encoder switching,
When switching from the 03 fax encoder 12 to the multipulse encoder 13 at time t2, a multipulse encoded signal is output for about 50 milliseconds, resulting in erroneous recognition by the receiving G3 fax terminal. This problem arises.

An object of the present invention is to provide an encoding device that solves these problems.

[Means to solve the problem]

The present invention includes two types of encoders having different encoding processing times, a switch for switching the digital outputs of these encoders, and a switch control circuit for controlling which encoder is selected by the switch. In the encoding device that converts a manually input analog signal into a digital code, the switch control circuit includes means for delaying the switching timing of the switch in response to processing delays of the two types of encoders. It is characterized by having

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

In this embodiment, the configuration of the switch changeover control circuit 16 in the encoding apparatus shown in FIG. 3 is changed. That is, the switch switching control circuit 6 of this embodiment includes a switching timing delay circuit 7.

G3 fax encoder 2 is identical to 63 fax encoder 12 of FIG. 3, multipulse encoder 3 is identical to multipulse encoder 13 of FIG. 3, and switch 4 is identical to 63 fax encoder 12 of FIG. The switch 14 is the same as the switch 14 shown in FIG.

The switching timing delay circuit 7 has two types of encoders 2
．． It has a function of delaying the switching timing of switch 4 in response to the processing delay of step 3.

In the figure, 1 is an input terminal, and 5 is an output terminal.

Next, the operation of this embodiment will be explained. FIG. 2 is a timing diagram of the encoding device shown in FIG. 1, and (a) is a switch switching signal input from the switch switching control circuit 6 to the switch 4 (“L” selects 03 fax encoder 2).
, (b) shows the encoded digital output output from the output terminal 5, and (c) shows the decoded output waveform of the opposing decoder.

An analog signal inputted from an input terminal 1 is inputted to two types of 63 fax encoder 2° multipulse encoder 3 having different processing times and to a switch changeover control circuit 6. When the switch switching control circuit 6 receives switching information, the switching timing delay circuit 7
As a result, the switching timing is delayed according to the processing time of the encoder 2.3. In this embodiment, when switching from the G3 fax encoder 2 to the multipulse encoder 3, the switching timing is delayed by 50 milliseconds.

That is, at time t3 in FIG. 2(a), the 03 fax encoder 2 is switched to the multipulse encoder 3. According to this, even if switching is performed while the G3 fax signal is encoded and output, the multi-pulse encoded signal will not be output, so that the G3 fax terminal on the receiving side will not misrecognize it.

〔Effect of the invention〕

As explained above, the encoding device of the present invention controls the switching timing of the encoder in accordance with the processing delay of the encoder, so that the encoding device can limit the transmission target to audio only.
In 0DEC, there is an effect that data signals can also be transmitted.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing one embodiment of the present invention, and FIG. 2 is a diagram showing an embodiment of the present invention.
FIG. 3 is a diagram showing a conventional encoding device, and FIG. 4 is a timing diagram of the conventional encoding device shown in FIG. 1... Input terminal 2... G3 Fax encoder 3... Multi-pulse encoding H 4... Switch 5... Output terminal 6...・Switch switching control circuit agent Patent attorney Yoshiyuki Iwasa Figure 2

Claims (1)

[Claims] (1) Two types of encoders with different encoding processing times, a switch that switches the digital output of these encoders, and a switch control circuit that controls which encoder is selected by this switch. In the encoding device that converts an input analog signal into a digital code, the switch control circuit has means for delaying the switching timing of the switch in response to processing delays of the two types of encoders. An encoding device characterized by: