Is there a way to play only a portion of an audio file (Seek. Play(duration in ms)). Feature Request.

[sdattatri]

Hi,
I am building an karaoke type of app. I have one large audio file with the entire song and the lyrics in english. I highlight one line at a time and play the corresponding audio once and then again (at lower volume) for the listener to sing along.

I have the 'start time' and 'duration' of audio corresponding to each line and use seek to start at the correct start time and setTimeout function to stop at the end of the duration. setTimeout however is not very accurate and so there are different periods of lag between devices (On some devices setTimeout seems to get called even before the given msecs, which is quite surprising. So much so, that I am even hesitant to state this!)

Is there a way by which I can play the audio file only for a specified duration? Current code is as follows:

localPlayer.seek(verseTiming.start * 1000, () => {
          localPlayer.play(
            playCallback(
              verseTiming.duration * 1000,
            ),
          );
        });

const playCallback = (msecs) => {
    setTimeout(() => {
        localPlayer.stop(stopCallback());
    }, msecs);
  };

Instead, I would like to use it as follows:

localPlayer.seek(verseTiming.start * 1000, () => {
          localPlayer.play(verseTiming.duration * 1000);
        });

[rustygloves]

I would like to have the same functionality.

We currently require this to play segments of an audio file with accompanying text animation, essentially in a very similar way to karaoke. Our current workaround is using cuepoints:

updatePlaybackStatus = () => {
    const {currentTime} = this.player;
    const {stopMillis} = this.state;
    if (this.player.isPlaying && stopMillis > 0 && currentTime >= stopMillis) {
      this.player.pause(() => {
        this.setState({stopMillis: 0}, this.playNext);
      });
    }
  };

this.player.seek(cueStart, err => {
        if (err) {
          console.log("player seek() error: ", {err});
        }
        this.player.play(err => {
          if (err) {
            console.log("player play() error: ", {err});
          }
          this.updateInterval = setInterval(() => {
            this.updatePlaybackStatus();
          }, 100);
          this.setState({stopMillis: cueEnd});
        });
      });

I have found the support for seeking is very good on iOS as compared to android devices.
Android devices seem to not work very well with exact millisecond timings.

[rustygloves]

It seems like there is no react-native library that currently supports this functionality from what I have seen

[disrae]

Can't this be done with the seek functionality and stop?
I may have misunderstood the statement, maybe the intervalTimer inaccuracies were the main issue.

[rustygloves]

At the time of posting it could not be reliably achieved with seek and stop. However I have not tested since the intervalTimer inaccuracies were resolved. We have since scrapped this implementation due in part to vary varied performance between Android and iOS devices.

[sdattatri]

I am sorry to hear that. I have used it in a Karoke type app that teaches people to chant various Hindu (for now) prayers. It works quite well on both platforms. If you have time, you can check out the app called Chant With Me. https://apps.apple.com/us/app/chant-with-me/id1548445902 https://play.google.com/store/apps/details?id=com.chantwithme It still has only a few hundred users, but seems to be performing reliably. I use seek and timers to stop the audio as required. Thanks for building the library. Cheers Sanjay

…

On Mon, Jun 21, 2021 at 4:43 PM rustygloves ***@***.***> wrote: At the time of posting it could not be reliably achieved with seek and stop. However I have not tested since the intervalTimer inaccuracies were resolved. We have since scrapped this implementation due in part to vary varied performance between Android and iOS devices. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#246 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AGHU2LL3L2NRMJMD2RJ3D43TT4NEXANCNFSM4S5T37KQ> .

-- Sanjay Dattatri,