Measuring device, measuring method, and program

Abstract

Provided are a measuring apparatus, a method, and a program for measuring, with high accuracy and at an arbitrary timing, a transmission delay difference between contents transmitted over two different lines. 【Solution means】In a measurement system, a measurement device 8 includes an input unit that inputs first audio data transmitted via a first transmission path 5A and second audio data transmitted via a second transmission path 5B, a detection unit that detects a maximum audio level in a predetermined section of the first audio data and also detects a maximum audio level in a predetermined section of the second audio data, and a measurement unit that, when the difference between the maximum audio levels of the first audio data and the second audio data is within a predetermined range, the difference between the audio levels at a time point before the maximum audio levels of the first audio data and the second audio data is within a predetermined range, and the difference between the audio levels at a time point after the first time point and the second time point is within the predetermined range, measures the time difference between the first time point and the second time point as a transmission delay difference in the first transmission path and the second transmission path.

Description

Technical Field

[0001] The present disclosure relates to a measuring device, a measuring method, and a program.

Background Art

[0002] In the relay of sports programs etc., in case of a failure, a backup line is constructed in most cases. At that time, the content passing through the two lines of the main line and the backup will reach the transmission destination with a time shift due to the difference in the transmission path. To eliminate this shift, a person performs a checking operation such as clapping hands in front of the on-site camera at the relay destination, and while visually observing the shift of the two contents at the receiving side of the transmission destination, operations such as adjusting the delay value (delay difference) are performed.

[0003] Note that Patent Document 1 describes a synchronization system for eliminating the delay difference between video and audio that occurs when video and audio are separated and processed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the case of the method of a person clapping hands on-site and visually observing the shift of the operation of clapping hands at the transmission destination to measure the shift between the two lines of the main line and the backup line, the shift is measured by a person's sense. In this case, it is difficult to accurately measure the shift between the active line and the backup line, and variations due to a person's sense also occur.

[0006] Also, to perform the measurement, it is necessary to introduce the operation of a person clapping hands on-site and equipment, and since the measurement is triggered by the operation of a person clapping hands on-site, the measurement is carried out on the receiving side according to the circumstances at the site.

[0007] The present disclosure has been made in view of the above circumstances, and an object of the present disclosure is to provide a technique capable of measuring, with high accuracy, a transmission delay difference between contents transmitted over two different lines and measuring at any timing.

Means for Solving the Problems

[0008] To achieve the above object, one aspect of the present disclosure is a measuring device including: an input unit that inputs first audio data of content transmitted via a first transmission path and second audio data of the content transmitted via a second transmission path; a detection unit that detects a maximum audio level in a predetermined section input for a certain time from a predetermined timing of the first audio data and detects a maximum audio level in a predetermined section input for a predetermined time from the predetermined timing of the second audio data; and a measurement unit that measures, as a transmission delay difference of the content in the first transmission path and the second transmission path, a time difference between a first time point and a second time point when a difference between the maximum audio level of the first audio data and the maximum audio level of the second audio data is within a predetermined range, a difference between an audio level at a time point before the first time point of the maximum audio level of the first audio data and an audio level at a time point before the second time point of the maximum audio level of the second audio data is within the predetermined range, and a difference between an audio level at a time point after the first time point and an audio level at a time point after the second time point is within the predetermined range.

[0009] One aspect of the present disclosure is a measurement method performed by a measuring device, the method comprising: inputting first audio data of content transmitted via a first transmission path and second audio data of the content transmitted via a second transmission path; detecting a maximum audio level in a predetermined section input within a certain time from a predetermined timing of the first audio data, and detecting a maximum audio level in a predetermined section input within the certain time from the predetermined timing of the second audio data; measuring a time difference between a first time point and a second time point as a transmission delay difference of the content in the first transmission path and the second transmission path when a difference between the maximum audio level of the first audio data and the maximum audio level of the second audio data is within a predetermined range, a difference between an audio level at a time point before the first time point of the maximum audio level of the first audio data and an audio level at a time point before the second time point of the maximum audio level of the second audio data is within the predetermined range, and a difference between an audio level at a time point after the first time point and an audio level at a time point after the second time point is within the predetermined range.

[0010] One aspect of the present disclosure is a program for causing a computer to function as the above-described measuring device.

Advantages of the Invention

[0011] According to the present disclosure, it is possible to provide a technique for measuring a transmission delay difference of content transmitted over two different lines with high accuracy and measuring at an arbitrary timing.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

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Figure 6

[0013] Embodiments of the present disclosure will be described with reference to the accompanying drawings. In this specification and the drawings, the same reference numerals denote the same or corresponding parts.

[0014] FIG. 1 is an overall configuration diagram of the measurement system according to the present embodiment. In the present embodiment, content (video) captured at a site such as a relay destination is transmitted to a transmission destination (for example, a broadcasting station) via two transmission paths (main line, standby line).

[0015] The illustrated measurement system includes a camera 2 disposed at the site, a microphone 3, and two multiplexing / encoding devices 4A and 4B. The measurement system also includes two demultiplexing / decoding devices 6A and 6B disposed at the transmission destination, an audio interface 7, and a measurement device 8.

[0016] At the site, the camera 2 captures an event such as a sports game or a concert held at, for example, a stadium 1, and outputs the captured video to the multiplexing / encoding device 4A and the multiplexing / encoding device 4B. The microphone 3 converts ambient sound into an electrical signal, and outputs the converted electrical signal of the sound to the multiplexing / encoding device 4A and the multiplexing / encoding device 4B.

[0017] The multiplexing / encoding device 4A is the main device, and the multiplexing / encoding device 4B is a backup sub-device. The multiplexing / encoding device 4A multiplexes and encodes the video and audio input from the camera 2 and the microphone 3 to generate content (transmission data), and transmits it to the demultiplexing / decoding device 6A via the transmission path 5A. Similarly, the multiplexing / encoding device 4B multiplexes and encodes the video and audio input from the camera 2 and the microphone 3 to generate content, and transmits it to the demultiplexing / decoding device 6B via the transmission path 5B.

[0018] The transmission path 5A (first transmission path) is the main line, and the transmission path 5B (second transmission path) is the sub standby line. The transmission path 5A and the transmission path 5B are different transmission paths. For example, the transmission path 5A may be a transmission path using an optical fiber, and the transmission path 5B may be a transmission path via a satellite. Also, the transmission path 5A and the transmission path 5B may be the same type of transmission line but with different routes.

[0019] The separation and decoding device 6A is the main device, and the separation and decoding device 6B is the sub standby device. The separation and decoding device 6A decodes the content transmitted via the transmission path 5A, separates it into video and audio, and outputs the separated first audio data to the audio interface 7. Similarly, the separation and decoding device 6B decodes the content transmitted via the transmission path 5B, separates it into video and audio, and outputs the separated second audio data to the audio interface 7.

[0020] The audio interface 7 inputs the first audio data output from the separation and decoding device 6A and the second audio data output from the separation and decoding device 6B to the measuring device 8 via USB (Universal Serial Bus). The audio interface 7 is an external general-purpose device for inputting audio data to the measuring device 8. For the audio interface 7, for example, RCA terminals (RCA cables) can be used.

[0021] The measuring device 8 measures and outputs the transmission delay difference (delay value) of the audio transmitted via two different transmission paths 5A and 5B. The transmission delay difference output by the measuring device 8 is input to an adjustment device (not shown) that adjusts the transmission delay difference of the content transmitted via the two transmission paths 5A and 5B. As the measuring device 8, a general-purpose computer such as a PC can be used.

[0022] Figure 2 is a block diagram showing a configuration example of the measuring device 8 of the present embodiment. The illustrated measuring device 8 includes an input unit 81, a detection unit 82, a measurement unit 83, and a storage unit 84.

[0023] The input unit 81 inputs the first audio data of the content transmitted via the transmission path 5A and the second audio data of the content transmitted via the transmission path 5B, and stores them in the storage unit 84.

[0024] To the input unit 81, the first audio data output from the separation / decoding device 6A and the second audio data output from the separation / decoding device 6B are directly input via the audio interface 7.

[0025] The detection unit 82 detects the maximum audio level in a predetermined section input for a certain time from a predetermined timing of the first audio data, and also detects the maximum audio level in a predetermined section input for a certain time from the predetermined timing of the second audio data.

[0026] The detection unit 82 may detect the maximum audio level for each predetermined section in a plurality of predetermined sections input for a certain time from a plurality of timings of the first audio data, and also detect the maximum audio level for each predetermined section in a plurality of predetermined sections input for a certain time from the plurality of timings of the second audio data.

[0027] When the difference between the maximum audio level of the first audio data and the maximum audio level of the second audio data is within a predetermined range, and the difference between the audio level at the time point before the first time point of the maximum audio level of the first audio data and the audio level at the time point before the second time point of the maximum audio level of the second audio data is within the predetermined range, and the difference between the audio level at the time point after the first time point and the audio level at the time point after the second time point is within the predetermined range, the measurement unit 83 measures the time difference between the first time point and the second time point as the transmission delay difference of the content in the transmission paths 5A and 5B.

[0028] When each transmission delay difference measured in a plurality of predetermined sections is the same for a predetermined number of consecutive times, the measurement unit 83 may output the transmission delay difference.

[0029] The measurement unit 83 may measure the time difference between the first time point and the second time point as the transmission delay difference when the difference between the maximum voice level of the first voice data and the voice levels at the time points before and after the first time point of the maximum voice level exceeds a threshold value, and when the difference between the maximum voice level of the second voice data and the voice levels at the time points before and after the second time point of the maximum voice level exceeds a threshold value.

[0030] The storage unit 84 stores the first voice data and the second voice data.

[0031] Next, the measurement process of the measuring device 8 of the present embodiment will be described with reference to FIGS. 3 to 5.

[0032] FIG. 3 is a flowchart showing an example of the measurement process of the measuring device 8 of the present embodiment. The illustrated measurement process is performed as a preparatory work before the start of transmission of the content to be broadcast or distributed. For example, it can be performed at an arbitrary timing after the lines of the two transmission paths 5A and 5B are connected.

[0033] The measuring device 8 inputs the first voice data and the second voice data respectively output from the separation / decoding devices 6A and 6B via the voice interface 7 (S11). The first voice data is the voice data of the content transmitted via the transmission path 5A, and the second voice data is the voice data of the content transmitted via the transmission path 5B.

[0034] The measuring device 8 measures the transmission delay difference of the content using the input first voice data and second voice data. For example, when the user inputs a measurement start instruction to the measuring device 8, the measuring device 8 may start the processing after S12.

[0035] First, the measuring device 8 detects the maximum audio level in a predetermined section input within a certain period from a predetermined timing of the first audio data, and also detects the maximum audio level in a predetermined section input within a certain period from the predetermined timing of the second audio data (S12). Specifically, the measuring device 8 extracts, from the first audio data, the section data of a predetermined section that reaches the separation and decoding device 6A at an arbitrary time (a certain time width from a predetermined time) and is input to the measuring device 8, and detects the maximum audio level of the section data. Similarly, the measuring device 8 extracts, from the second audio data, the section data of a predetermined section that reaches the separation and decoding device 6B at the arbitrary time and is input to the measuring device 8, and detects the maximum audio level of the section data.

[0036] For example, the measuring device 8 may extract, respectively, the predetermined sections of the first audio data and the predetermined section of the second audio data input within a certain period from the timing when a predetermined time has elapsed since the measurement start instruction was input.

[0037] Then, the measuring device 8 detects each audio level at a time point before and after the first time point of the maximum audio level of the first audio data and each audio level at a time point before and after the second time point of the maximum audio level of the second audio data (S13).

[0038] FIG. 4 illustrates an audio waveform 41 of a predetermined section of the first audio data and an audio waveform 42 of a predetermined section of the second audio data. The vertical axis of the illustrated graph indicates the normalized audio level, and the horizontal axis indicates time. The illustrated horizontal axis indicates the time of a predetermined section (for example, 2 seconds) with a resolution of 88,200 points.

[0039] The measuring device 8 detects the maximum audio level m1 in the audio waveform 41 of the first audio data and the maximum audio level m2 in the audio waveform 42 of the second audio data. The measuring device 8 detects each audio level a1, b1 at a time point before and after the first time point of the maximum audio level m1 of the first audio data and each audio level a2, b2 at a time point before and after the second time point of the maximum audio level m2 of the second audio data.

[0040] The front and rear voice levels are the voice levels at a point in time that is a predetermined time before or after the first point in time or the second point in time, in the forward and backward directions. Here, the point in time is 1000 points before or after the first point in time or the second point in time, but it is not limited to this. Here, the front and rear points in time are the same distance from the first point in time or the second point in time as the center, but they may be different.

[0041] Then, the measuring device 8 compares the maximum voice level of the first voice data, the voice levels at the points in time before and after it, the maximum voice level of the second voice data, and the voice levels at the points in time before and after it, and determines whether the difference in voice levels at all points in time is within a predetermined range (S14).

[0042] In the example shown in FIG. 4, the measuring device 8 compares the maximum voice level m1 of the first voice data, the respective voice levels a1, b1 before and after it, the maximum voice level m2 of the second voice data, and the respective voice levels a2, b2 before and after it.

[0043] Specifically, the measuring device 8 compares the maximum voice levels (m1, m2) with each other and determines whether the difference therebetween is within a predetermined range. That is, it determines whether there are similar maximum voice levels. Further, the measuring device 8 compares the voice levels (a1, a2), (b1, b2) at the points in time before and after the maximum voice level with each other and determines whether the difference therebetween is within a predetermined range.

[0044] When the difference in voice levels at at least one point in time exceeds the predetermined range (S14: NO), the measuring device 8 returns to S12 and repeats the subsequent processing. In this case, the measuring device 8 detects the maximum voice level in another predetermined section input within a certain time from a timing different from the previous time of the first voice data, and detects the maximum voice level in another predetermined section input within a certain time from the different timing of the second voice data (S12).

[0045] When the difference in audio levels at all times is within a predetermined range (S14: YES), the measuring device 8 also determines whether the difference between the maximum audio level of the first audio data and each audio level at times before and after the first time of the maximum audio level exceeds a threshold value, and whether the difference between the maximum audio level of the second audio data and each audio level at times before and after the second time of the maximum audio level exceeds a threshold value (S15).

[0046] In the example shown in FIG. 4, the measuring device 8 calculates the difference between the maximum audio level m1 of the first audio data and the audio level a1, the difference between the maximum audio level m1 and the audio level b1, the difference between the maximum audio level m2 of the second audio data and the audio level a2, and the difference between the maximum audio level m2 and the audio level b2, and determines whether all the differences exceed a predetermined threshold value.

[0047] This is a mechanism for avoiding incorrect measurements when the audio data includes data with a continuous maximum audio level such as a 1 kHz reference signal.

[0048] When all the differences exceed the threshold value (S16: YES), the measuring device 8 measures the time difference between the first time of the first audio data and the second time of the second audio data as the transmission delay difference of the content in the transmission paths 5A and 5B (S17). On the other hand, when at least one difference is below the threshold value (S16: NO), the measuring device 8 returns to S12 and repeats the subsequent processing.

[0049] Then, when the transmission delay difference measured in S17 becomes the same value for a continuous predetermined number of times (S18: YES), the measurement device 8 may output (display) the transmission delay difference measured in S17 (S19). In the present embodiment, by repeatedly performing until the transmission delay difference of the same value is continuously measured a predetermined number of times (for example, 3 times), a more accurate transmission delay difference can be measured. When the transmission delay difference measured in S17 does not become the same value for a continuous predetermined number of times (S18: NO), the measurement device 8 returns to S12 and repeats the subsequent processing. The measurement device 8 may, for example, extract the next predetermined section of the first audio data and the second audio data at the timing of returning to S12, or at the timing when a predetermined time has elapsed since the extraction of the previous predetermined section, extract the next predetermined section of the first audio data and the second audio data.

[0050] Note that the same value may include a predetermined error. For example, when the transmission delay difference is expressed in frame units, if it is the same up to the first decimal place, it may be regarded as the same value. Here, the frame refers to a video frame that switches 30 times per second, and the duration of one frame is 1 second / 30 times = 33 ms. When considering up to the first decimal place, it is 1 / 10 of 33 ms. Therefore, the measurement device 8 may determine that it is the same value when the error is less than 3.3 ms, and determine that it does not correspond to the same value when there is a temporal deviation of 3.3 ms or more.

[0051] FIG. 5 shows an example of a message of the transmission delay difference output by the measurement device 8. Here, the transmission delay difference is expressed in frame units and time (ms) units. In the illustrated example, it shows that the first audio data (ch1) is 27.0 frames (891.0 ms) earlier than the second audio data (ch2). The measurement device 8 calculates the number of frames by dividing the time (ms) of the measured transmission delay difference by 33 ms. Note that the measurement device 8 may output or display the graph of the audio waveform shown in FIG. 4 together with the message shown in FIG. 5 on a display.

[0052] The measuring device 8 of the present embodiment described above includes an input unit 81 that inputs first audio data of content transmitted via a first transmission path and second audio data of the content transmitted via a second transmission path, a detection unit 82 that detects a maximum audio level in a predetermined section input for a certain period from a predetermined timing of the first audio data and also detects a maximum audio level in a predetermined section input for a certain period from the predetermined timing of the second audio data, and a measurement unit 83 that measures, as a transmission delay difference of the content in the first transmission path and the second transmission path, a time difference between a first time point and a second time point when a difference between the maximum audio level of the first audio data and the maximum audio level of the second audio data is within a predetermined range, a difference between an audio level at a time point before the first time point of the maximum audio level of the first audio data and an audio level at a time point before the second time point of the maximum audio level of the second audio data is within the predetermined range, and a difference between an audio level at a time point after the first time point and an audio level at a time point after the second time point is within the predetermined range.

[0053] In the present embodiment, it is possible to provide a technique for measuring a transmission delay difference of content transmitted through two different lines with high accuracy and measuring it at an arbitrary timing.

[0054] Specifically, by measuring the transmission delay difference using the audio data of the content, it is possible to measure the transmission delay difference of the content with an accuracy in milliseconds (ms), which is finer than in video frame units.

[0055] Also, in the present embodiment, it is possible to measure the transmission delay difference only by inputting each audio data of the content transmitted through two different lines from the site to the measuring device 8 without a person at the site performing an operation such as clapping hands. As a result, in the present embodiment, on the receiving side of the transmission destination, there is no need to measure the transmission delay difference in cooperation with the site, and the transmission delay difference can be measured at an arbitrary timing.

[0056] In addition, in this embodiment, by simply preparing a measurement device 8 using a general-purpose computer and an audio input interface 7, it is possible to measure the transmission delay difference of content transmitted over two different lines. That is, the measurement device 8 of this embodiment can be realized by implementing an application program having the above-described measurement function on a general-purpose computer. Therefore, in this embodiment, it is possible to measure the transmission delay difference of content at low cost.

[0057] The measurement device 8 of the present embodiment described above can use, for example, a general-purpose computer system as shown in FIG. 6. The illustrated computer system includes a CPU (Central Processing Unit, processor) 901, a memory 902, a storage 903 (HDD: Hard Disk Drive, SSD: Solid State Drive), a communication device 904, an input device 905, and an output device 906. The memory 902 and the storage 903 are storage devices. In this computer system, each function of the measurement device 8 is realized by the CPU 901 executing a predetermined program (application program) loaded on the memory 902. The program may be constructed in a general-purpose programming language such as Python.

[0058] Also, the measurement device 8 may be implemented on one computer, or may be implemented on a plurality of computers. Further, the measurement device 8 may be a virtual machine implemented on a computer. The program of the measurement device 8 can be stored in a computer-readable recording medium such as an HDD, SSD, USB (Universal Serial Bus) memory, CD (Compact Disc), DVD (Digital Versatile Disc), or can be distributed via a network. The computer-readable recording medium is, for example, a non-transitory recording medium.

[0059] Note that the present disclosure is not limited to the above-described embodiments, and various modifications are possible within the scope of the gist thereof.

Explanation of Signs

[0060] 2: Camera 3: Microphone 4A, 4B: Multiplexing / Encoding Device 5A, 5B: Transmission Path 6A, 6B: Separation / Decoding Device 7: Audio Interface 8: Measuring Device 81: Input Unit 82: Detection Unit 83: Measuring Unit 84: Memory Unit

Claims

1. An input unit that inputs first audio data of content transmitted via a first transmission path and second audio data of the content transmitted via a second transmission path; A detection unit that detects a maximum audio level in a predetermined section input for a certain period from a predetermined timing of the first audio data, and detects a maximum audio level in a predetermined section input for a certain period from the predetermined timing of the second audio data; When the difference between the maximum audio level of the first audio data and the maximum audio level of the second audio data is within a predetermined range, and the difference between the audio level at the time point before the first time point of the maximum audio level of the first audio data and the audio level at the time point before the second time point of the maximum audio level of the second audio data is within the predetermined range, and the difference between the audio level at the time point after the first time point and the audio level at the time point after the second time point is within the predetermined range, a measurement unit that measures the time difference between the first time point and the second time point as the transmission delay difference of the content in the first transmission path and the second transmission path; The time difference between the first time point and the time point before it is the same as the time difference between the second time point and the time point before it, and the time difference between the first time point and the time point after it is the same as the time difference between the second time point and the time point after it Measurement device.

2. The detection unit detects the maximum audio level for each predetermined section in a plurality of predetermined sections input for a certain period from a plurality of timings of the first audio data, and detects the maximum audio level for each predetermined section in a plurality of predetermined sections input for a certain period from the plurality of timings of the second audio data, The measurement unit outputs the transmission delay difference when each transmission delay difference measured in a plurality of predetermined sections is the same for a predetermined number of consecutive times The measurement device according to claim 1.

3. The measurement unit is When the difference between the maximum audio level of the first audio data and the maximum audio level of the second audio data is within a predetermined range, and the difference between the audio level at the time point before the first time point of the maximum audio level of the first audio data and the audio level at the time point before the second time point of the maximum audio level of the second audio data is within the predetermined range, and the difference between the audio level at the time point after the first time point and the audio level at the time point after the second time point is within the predetermined range, and further, when the difference between the maximum voice level at the first time point of the first voice data and the voice levels at time points before and after the first time point exceeds a threshold value, and when the difference between the maximum voice level at the second time point of the second voice data and the voice levels at time points before and after the second time point exceeds a threshold value, measure the time difference between the first time point and the second time point as the transmission delay difference The measuring device according to claim 1.

4. A measuring method performed by a measuring device, input the first voice data of the content transmitted via the first transmission path and the second voice data of the content transmitted via the second transmission path, detect the maximum voice level in a predetermined section input within a certain time from a predetermined timing of the first voice data, and detect the maximum voice level in a predetermined section input within a certain time from the predetermined timing of the second voice data, when the difference between the maximum voice level of the first voice data and the maximum voice level of the second voice data is within a predetermined range, and the difference between the voice level at the time point before the first time point of the maximum voice level of the first voice data and the voice level at the time point before the second time point of the maximum voice level of the second voice data is within the predetermined range, and the difference between the voice level at the time point after the first time point and the voice level at the time point after the second time point is within the predetermined range, measure the time difference between the first time point and the second time point as the transmission delay difference of the content in the first transmission path and the second transmission path, the time difference between the first time point and the time point before it is the same as the time difference between the second time point and the time point before it, and the time difference between the first time point and the time point after it is the same as the time difference between the second time point and the time point after it Measuring method.

5. A program for causing a computer to function as the measuring device according to any one of claims 1 to 3.

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