CN102685549B - A method and device for switching real-time and non-real-time program content of train sound broadcasting - Google Patents

Abstract

The invention discloses a method and device for switching between real-time and non-real-time program content of train sound broadcasting. The method includes the following processing: in the state of train real-time broadcasting, judging the buffer data status of train real-time broadcasting, when the buffer data status is determined to be When the duration of the cache clearing state reaches the first predetermined time, the train broadcast is switched from the train real-time broadcast state to the cache play state, and the pad material stored in the cache is started in advance, and the pad material is played; in the cache play state, Judging the available buffer state of the train real-time broadcast, when it is determined that the duration of the available buffer reaches the second predetermined time, the train broadcast is switched from the buffer play state to the train real-time broadcast state, and the train real-time broadcast is played. Through the above processing, the seamless broadcasting of train sound broadcasting is truly realized.

Description

A method and device for switching real-time and non-real-time program content of train sound broadcasting

technical field

The invention relates to the field of multimedia broadcasting, in particular to a method and device for switching real-time and non-real-time program content of train sound broadcasting.

Background technique

At present, through the multi-channel delay time diversity mechanism, it is possible to realize uninterrupted real-time broadcasting of trains under most tunnel blocking conditions. The multi-channel delay time diversity mechanism solves the tunnel occlusion problem in most practical environments at the cost of real-time program delay.

The multi-channel delay time diversity mechanism delays the real-time audio signal by N channels at equal intervals. The system broadcasts the signal with the largest delay, and stores the other N channels of signals with real-time and smaller delays in the cache as the signal with the largest delay. backup. When the signal of this channel is interrupted, the receiver extracts valid data from the backup signals of N channels, and through code stream splicing, it solves the problem of receiving interruption caused by signal occlusion in a short period of time.

The performance of the multi-channel delay time diversity mechanism is mainly affected by two parameters: one parameter is the delay time, and the delay time refers to the interval from the first channel diversity signal to the last channel diversity signal. A larger delay time can resist a longer Tunnel, but if the delay time is too large, it will reduce the timeliness of broadcasting news. Another parameter is the interval between two adjacent channels in the multi-channel diversity signal, that is, the time window threshold. The smaller the time window threshold, the shorter the time it takes for the receiver to splice the complete code stream to fill the buffer. Among them, N is the number of delay paths, and the larger the number of delay paths means more data backup, but the amount of data transmission also increases accordingly.

However, in practical applications, in rare cases such as ultra-long tunnels and ultra-dense tunnel groups, it is still impossible for the multi-channel delay time diversity mechanism to completely avoid the interruption of train satellite real-time broadcasting. The technical problems existing in the prior art are described below by taking the 10-way delay time diversity mechanism with a delay time T _delay =10 min as an example.

If the tunnel length t _tunnel exceeds the delay time T _delay given by the multi-channel delay time diversity mechanism, that is, t _tunnel > T _delay , then the train real-time broadcasting system will experience signal interruption, and the interruption time t _mute = t _tunnel - T _delay . Fig. 1 is a schematic diagram of the interruption of the real-time broadcast signal of the train caused by the ultra-long tunnel in the prior art. As shown in Fig. 1, the train passes through a 20-minute long tunnel, and it has been receiving normally before entering the tunnel. Then the real-time broadcast of the train in the first 10 minutes of the tunnel will be played normally, and the signal will be interrupted in the next 10 minutes. The interruption doesn't resume until after exiting the tunnel.

If the interval t _open between the tunnels is too compact and dense, which is smaller than the time window threshold T _delay /N, that is, t _open <T _delay /N, then there will be glitches in the real-time broadcast signal of the train, and the duration of each signal glitch is T _delay /Nt _open , the sum of durations of all glitches is t _mute =T _delay -N·t _open . Fig. 2 is a schematic diagram of the interruption of the real-time broadcast signal of the train caused by ultra-dense tunnel groups in the prior art. Receive time, and the time window threshold is 1 minute. The train's real-time broadcast signal will not be interrupted in tunnel 1, but in tunnel 2, as the receiver buffer is cleared, and the 40 seconds before exiting tunnel 1 and entering tunnel 2 is less than the time window threshold, the train's real-time broadcast signal will appear Glitch phenomenon. The signal was interrupted a total of 10 times, each lasting 20 seconds, and the glitch would not end until it exited the tunnel.

Contents of the invention

The present invention provides a method and device for switching between real-time and non-real-time program content of train sound broadcasting, which is used to solve the problem that the multi-channel delay time diversity mechanism cannot Completely avoid the problem of train satellite real-time broadcast interruption.

The invention provides a method for switching between real-time and non-real-time program content of train sound broadcasting, the method includes the following processing:

Under the train real-time broadcast state, the cache data state of the train real-time broadcast is judged, and when it is determined that the cache data state is that the duration of the cache empty state reaches the first predetermined time, the train broadcast is switched from the train real-time broadcast state to the buffer play state , start the matting material pre-stored in the cache, and play the matting material;

In the cache play state, the available cache state of the train real-time broadcast is judged, and when it is determined that the duration of the available cache reaches the second predetermined time, the train broadcast is switched from the cache play state to the train real-time broadcast state, and the train real-time broadcast is played .

The present invention also provides a real-time and non-real-time program content switching device for train sound broadcasting, the device comprising:

The first switching module is used for judging the cached data state of the train’s real-time broadcast in the train’s real-time broadcast state, and when the duration of the cached data state is determined to be the cache empty state reaches the first predetermined time, the train broadcast is broadcasted by the train in real time The broadcast state is switched to the cache play state, the padding material pre-stored in the cache is started, and the first play module is called;

The first playback module is used to play pad material;

The second switching module is used to judge the available buffer state of the train real-time broadcast in the buffer play state, and switch the train broadcast from the buffer play state to the train real-time broadcast when it is determined that the duration of the available buffer reaches the second predetermined time state, and call the second playback module;

The second playing module is used for playing train real-time broadcasting.

The beneficial effects of the present invention are as follows:

On the basis of the multi-channel delay time diversity mechanism, the embodiment of the present invention compiles a novel pad program material suitable for the actual application environment of train broadcasting, and designs a switching mechanism between the pad material and the real-time broadcast signal , which solves the problem in the prior art that the multi-channel delay time diversity mechanism cannot completely avoid the interruption of train satellite real-time broadcast when the train passes through an ultra-long tunnel or ultra-dense tunnel group, etc., and truly realizes the seamless broadcast of train broadcast out.

Description of drawings

Fig. 1 is the schematic diagram that the ultra-long tunnel in the prior art causes the train real-time broadcast signal to be interrupted;

Fig. 2 is a schematic diagram of interruption of train real-time broadcast signal caused by ultra-dense tunnel group in the prior art;

Fig. 3 is the flow chart of the real-time and non-real-time program content switching method of train sound broadcasting according to an embodiment of the present invention;

4 is a schematic diagram of an ultra-long tunnel switching mechanism according to an embodiment of the present invention;

5 is a schematic diagram of an ultra-dense tunnel group switching instance 1 according to an embodiment of the present invention;

6 is a schematic diagram of an ultra-dense tunnel group switching instance 2 according to an embodiment of the present invention;

7 is a schematic diagram of an ultra-dense tunnel group switching instance 3 according to an embodiment of the present invention;

Fig. 8 is a schematic structural diagram of a real-time and non-real-time program content switching device for train sound broadcasting according to an embodiment of the present invention.

Detailed ways

In order to solve the problem in the prior art that the multi-channel delay time diversity mechanism cannot completely avoid the interruption of the train satellite real-time broadcast when the train passes through an ultra-long tunnel or an ultra-dense tunnel group, etc., the present invention provides a train sound broadcast real-time With reference to the method and device for switching non-real-time program content, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

method embodiment

According to an embodiment of the present invention, a method for switching between real-time and non-real-time program content of train sound broadcasting is provided. train broadcast. Fig. 3 is the flow chart of the real-time and non-real-time program content switching method of train sound broadcasting according to the embodiment of the present invention, as shown in Figure 3, according to the train sound broadcasting real-time and non-real-time program content switching method of the embodiment of the present invention comprises:

Step 301, in the real-time train broadcasting state, judge the cached data state of the train’s real-time broadcasting, and switch the train broadcasting from the train’s real-time broadcasting state to Cache the playing state, start the pad material pre-stored in the cache, and play the pad material; the pad material may include clips and music.

On the other hand, the starting basis for switching from train real-time broadcasting to pad material can be judging the splicing data-free time (that is, the duration of the cache data state as the cache empty state), this time can be artificially set, and in the implementation of the present invention In the example, this time is 5 seconds.

It should be noted that, considering the limitation of FLASH storage space, it is impossible to store long-term pad music materials. Therefore, in the embodiment of the present invention, for interruptions of different durations, a piece of soothing music of 60 seconds can be selected, which can be played in a loop without obvious interruption feeling. In addition, in order to reflect the characteristics of the train broadcast, a 20-second clip can be added before the 60-second soothing music. The clips are only played once each time, after which the music can be played in a loop. In this way, the duration of the padding material is 80 seconds, consisting of 20 seconds of footage and 60 seconds of music, and the beginning and ending 5 seconds of the padding material are made to fade in and fade out.

In step 301, when playing the pad material, a 20-second clip can be played once, and 60-second music can be played in a loop.

Step 302, in the cache play state, judge the available cache state of the train real-time broadcast, when it is determined that the duration of the available cache reaches the second predetermined time, switch the train broadcast from the cache play state to the train real-time broadcast state, and play The train broadcasts in real time.

Preferably, in the embodiment of the present invention, the real-time broadcast of the train can be played after the current background material is played.

It should be noted that the above-mentioned second predetermined time is a time window threshold, wherein the time window threshold is the delay time interval between two adjacent channels in the multi-channel diversity signal of the multi-channel delay time diversity mechanism.

On the other hand, the starting basis for switching from pad material to train real-time broadcasting can be to judge whether the continuous locking time (that is, the duration of the available cache) reaches the time window threshold T _delay /N. In the embodiment of the present invention, The time window threshold may be 1 minute.

To sum up, in practical applications, the real-time receiver can make a judgment on the state of the buffered data. When there is a continuous buffer empty state for 5 seconds, the real-time broadcast of the train is switched to the buffered playback state, and the playback of the matting material is started. The clip is played once, and the music can be played in a loop. During the playback, the status of the available cache can be monitored, and the time can be counted through the lock state. If the duration of the lock state reaches the time window threshold of 1 minute for complete playback, the padding material will be played after the end of the play. Switch to train real-time broadcasting, otherwise continue to broadcast the next period of pad material music.

It can be seen from the above processing that due to the introduction of the padding mechanism, the real-time broadcast of the train can automatically switch to the padding material when it is interrupted by occlusion, and automatically switch back to the real-time broadcast when it is not blocked. The above-mentioned technical solutions of the present invention will be described by way of example in conjunction with the accompanying drawings and examples.

Fig. 4 is a schematic diagram of an ultra-long tunnel switching mechanism according to an embodiment of the present invention. As shown in Fig. 4, the train has been receiving normally before entering a 20-minute tunnel, and the conductor has not manually operated it. Then the first 10 minutes in the tunnel is the real-time program playing normally, and after 5 seconds of silence, it transitions to a 20-second clip, and the music is played 10 times during the last 575 seconds of the train in the tunnel and 25 seconds after leaving the tunnel. 25 seconds is still not enough to judge whether the time window can reach 1 minute, so it is necessary to continue playing the music once. The train finds that the time window reaches 60 seconds 60 seconds after it leaves the tunnel, so it will switch to real-time broadcasting after 85 seconds after it leaves the tunnel.

Fig. 5 is a schematic diagram of an ultra-dense tunnel group switching example 1 according to an embodiment of the present invention. As shown in Fig. 5, section 1 is received normally throughout the whole process, section 2 is played in real time for 20 seconds, and after 5 seconds of silence, it transitions to a 20-second clip, and then 575 Play music 10 times in a second loop and take up 325 seconds of the section. Section 3 still cannot judge that the time window is sufficient 25 seconds after playing the music, so continue to play music for 60 seconds until the time window exceeds 60 seconds, and the subsequent time is 575 seconds. The live program has been playing normally.

Fig. 6 is a schematic diagram of an example 2 of ultra-dense tunnel group switching according to the embodiment of the present invention. As shown in Fig. 6, section 1 is normally played in the tunnel for 600 seconds, interrupted for 3 seconds, and is less than the threshold for starting pad materials, so section 2 continues Play normally for 20 seconds in real time, then mute for 5 seconds and then transition to a clip, then play the music 10 times in a loop for the last 575 seconds and take up 325 seconds of the section. Section 3 still cannot judge that the time window is sufficient 25 seconds after playing the music, so continue Play music for 60s until the time window exceeds 60 seconds, and the real-time program will be played normally for the next 575 seconds.

Fig. 7 is a schematic diagram of an example 3 of ultra-dense tunnel group switching according to the embodiment of the present invention. As shown in Fig. 7, road section 1 is normally played in the tunnel for 600 seconds, interrupted for 5 seconds, and then the clip is started; road section 2 continues to play the clip after 15 seconds, And start playing music, because the time window of section 2 is less than 60 seconds, so the music has been played in a loop, the last 625 seconds of section 2 and the first 35 seconds of section 3 play music 11 times in total; section 3 is 35 seconds after playing music It still cannot be judged that the time window is enough, so continue to play 60s of music until it is found that the time window exceeds 60 seconds, so the subsequent 565 seconds of section 3 is switched to playing real-time programs.

It can be seen from Fig. 5, Fig. 6, and Fig. 7 that the difference in the length of the tunnel 1 leads to the difference in the switching of real-time train broadcasting and matting materials, which proves that the mechanism of the embodiment of the present invention is effective in the face of complex and changeable tunnel environments. , its own flexible processing capabilities.

On the basis of the multi-channel delay time diversity mechanism, the embodiment of the present invention solves the off-air problem that the multi-channel delay time diversity mechanism itself cannot completely solve, and is an effective supplement to the multi-channel delay time diversity mechanism. The background material design method of clips and music that can be played in a loop not only leaves room for enhancing the brand and cultural connotation of train broadcasting, but also reflects the flexibility of pad broadcasting, effectively meeting the seamlessness of train broadcasting in terms of overall and details. broadcast needs. The comprehensive switching mechanism based on the judgment of the buffer state ensures the continuity of the train sound broadcasting, the immediacy and naturalness of the switching transition, and the priority of real-time broadcasting. With the introduction of this background material and its switching mechanism, the train radio will get rid of the embarrassment of long-term suspension and the irritability caused by sound glitches, and the audience will enjoy a more relaxed listening experience during the journey.

Device embodiment

According to an embodiment of the present invention, a real-time and non-real-time program content switching device for train sound broadcasting is provided. train broadcast. Fig. 8 is a schematic structural diagram of a real-time and non-real-time program content switching device for train sound broadcasting according to an embodiment of the present invention. As shown in Fig. 8 , the real-time and non-real-time program content switching device for train sound broadcasting according to an embodiment of the present invention includes: the first A switching module 80 , a first playing module 82 , a second switching module 84 , and a second playing module 86 . Next, the device for switching real-time and non-real-time program content of train sound broadcasting according to the embodiment of the present invention will be described in detail.

The first switching module 80 is used for judging the cached data state of the real-time train broadcast under the train real-time broadcast state, and when it is determined that the cached data state is that the duration of the cache empty state reaches the first predetermined time, the train broadcast is sent by the train The real-time broadcasting state is switched to the cache playing state, the padding material stored in the cache is started, and the first playback module 82 is called; the padding material includes clips and music.

On the other hand, the first switching module 80 switches the train broadcast from the train real-time broadcast state to the cache play state based on the judgment of the splicing data-free time (that is, the cache data state is the duration of the cache empty state), which The time can be set artificially, and in the embodiment of the present invention, the time is 5 seconds.

It should be noted that, considering the limitation of FLASH storage space, it is impossible to store long-term pad music materials. Therefore, in the embodiment of the present invention, for interruptions of different durations, a piece of soothing music of 60 seconds can be selected, which can be played in a loop without obvious interruption feeling. In addition, in order to reflect the characteristics of the train broadcast, a 20-second clip can be added before the 60-second soothing music. The clips are only played once each time, after which the music can be played in a loop. In this way, the duration of the padding material is 80 seconds, consisting of 20 seconds of footage and 60 seconds of music, and the beginning and ending 5 seconds of the padding material are made to fade in and fade out.

The first playing module 82 is used to play back-up material; preferably, when playing back-up material, the first playback module 82 can play a 20-second clip once and play 60-second music in a loop.

The second switching module 84 is used to judge the available buffer state of the train real-time broadcast in the buffer play state, and when it is determined that the duration of the available buffer reaches the second predetermined time, the train broadcast is switched from the buffer play state to the train real-time broadcast status, and call the second playback module 86;

It should be noted that the above-mentioned second predetermined time is a time window threshold, wherein the time window threshold is the delay time interval between two adjacent channels in the multi-channel diversity signal of the multi-channel delay time diversity mechanism.

On the other hand, the second switching module 84 switches the train broadcast from the buffer play state to the train real-time broadcast state based on whether the continuous locking time (that is, the duration of the available cache) reaches the time window threshold T _delay / N. In the embodiment of the present invention, the time window threshold may be 1 minute.

The second playing module 86 is used for playing the train real-time broadcast. Preferably, in the embodiment of the present invention, the second playing module 86 can play the real-time broadcast of the train after playing the current pad material.

In practical applications, the real-time receiver can make a judgment on the status of the buffered data. When there is a continuous buffer empty state for 5 seconds, the real-time broadcast of the train will switch to the buffered playback state, start the playback of the background material, play the movie once, and the music It can be played in a loop, and the status of the available cache can be monitored during the playback process. It can be timed through the lock state. If the duration of the lock state reaches the time window threshold of 1 minute for complete playback, it will switch to the real-time broadcast of the train after the padding material is played. , otherwise continue to play the next period of pad material music.

Through the application analysis of the pad material and its switching mechanism in the super-long tunnel and ultra-dense tunnel scenarios, an effective transition between real-time programs and pad programs can be achieved.

The design method of clips plus padding materials that can play music in a loop effectively meets the needs of seamless broadcasting of train broadcasting in terms of overall and details. The 80-second material will not take up too much space in FLASH; the clip design leaves room for enhancing the brand and cultural connotation of the train broadcast; the 1-minute period music reflects the flexibility of the pad broadcast, which can meet the needs of different durations ;The music can only be switched back to real time after the music is completely played, so as to avoid the audience feeling the interruption of the content; the fade-in and fade-out design avoids the blunt feeling that may be caused by switching.

The comprehensive switching mechanism based on the judgment of the cache status includes: after the cache is cleared and lasts for 5 seconds, it will switch from real-time to pad; if the continuous locking time reaches the time window threshold, it will switch from pad to real-time for 1 minute. This set of mechanisms guarantees the continuity of train sound broadcasting, the immediacy and naturalness of switching transitions, and the priority of real-time broadcasting to the greatest extent.

Although preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, and therefore, the scope of the present invention should not be limited to the above-described embodiments.

Claims (8)

1. a kind of real-time and non-real-time program content switching method of train sound broadcasting, it is characterized in that, described method comprises following processing: Under the train real-time broadcast state, the cache data state of the train real-time broadcast is judged, and when it is determined that the cache data state is that the duration of the cache empty state reaches the first predetermined time, the train broadcast is switched from the train real-time broadcast state to the cache In the playing state, start the padding material pre-stored in the cache, and play the padding material; In the cache play state, judge the available cache state of the real-time train broadcast, and switch the train broadcast from the cache play state to the Train real-time broadcast status, and play train real-time broadcast, wherein, the second predetermined time is the time window threshold, wherein, the time window threshold is the two adjacent channels in the multi-channel diversity signal of the multi-channel delay time diversity mechanism Delay time interval. 2 . The method according to claim 1 , wherein the padding material includes: clips and music, and the beginning and end of the padding material are faded in and faded out. 3 . 3. The method according to claim 2, wherein playing the matting material comprises: Play the clip once; Play said music on a loop. 4. The method according to claim 1, wherein said playing train real-time broadcast comprises: After playing the current padding material, the real-time broadcast of the train is played. 5. A real-time and non-real-time program content switching device for train sound broadcasting, characterized in that the device comprises: The first switching module is used for judging the cached data state of the train's real-time broadcast under the state of the train's real-time broadcast. The train real-time broadcast state is switched to the cache play state, the padding material pre-stored in the cache is started, and the first play module is called; The first playing module is used to play the padding material; The second switching module is used to judge the available buffer status of the real-time broadcast of the train in the buffer playing state, and when it is determined that the duration of the available buffer reaches a second predetermined time, the train broadcast is broadcast by the The buffered playback state is switched to the real-time broadcast state of the train, and the second playback module is called, wherein the second predetermined time is a time window threshold, wherein the time window threshold is a multi-channel delay time diversity mechanism. The delay time interval between two adjacent channels in the diversity signal; The second playing module is used to play the train real-time broadcast. 6 . The device according to claim 5 , wherein the padding material includes: clips and music, and the beginning and end of the padding material are faded in and faded out. 7. The device according to claim 6, wherein the first playback module is specifically used for: Play the trailer once; play the music in a loop. 8. The device according to claim 5, wherein the second playing module is specifically used for: After the first play module plays the current pad material, play the train real-time broadcast.