Having a scrollview instead of erasing and redrawing the content

[jbouaziz]

Hey!

Great job on the library! Really.
Would there be a way to have a scrollview instead of erasing what's been drawn already? You can try recording using the SoundCloud app to see what I'm talking about.

[syedhali]

Helloo, glad you're digging EZAudio! I think a scrolling waveform would be an awesome addition. Perhaps adding an additional EZPlotType like:

/**
 The types of plots that can be displayed in the view using the data.
 */
typedef NS_ENUM(NSInteger,EZPlotType){
  /**
   *  Plot that displays only the samples of the current buffer
   */
  EZPlotTypeBuffer,
  /**
   *  Plot that displays a rolling history of values using the RMS calculated for each incoming buffer
   */
  EZPlotTypeRolling,
  /**
   *  Plot that displays a scrolling, rolling history of values using the RMS calculated for each incoming buffer
   */
  EZPlotTypeScrolling,
};

and extending the plots to accompany the custom history buffer handling to support the scrolling (once full, add N data to front and remove N data from beginning of display buffer).

I'm currently busy working on an EZAudio version 0.0.3 with a couple bug fixes, updates, and extensions for the EZMicrophone, EZAudioFile, and EZOutput based on the emails I've been getting in the last few weeks. I'll put this on the radar for the next version 0.0.4 as an extension for the EZAudioPlot and EZAudioPlotGL.

Contributing

If anyone is interested in becoming an EZAudio contributor and would like to take a crack at implementing this scrolling waveform for either the EZAudioPlot or the EZAudioPlotGL I'd happily accept a pull request!

[jbouaziz]

I'll look into that, thanks!

[syedhali]

I hacked on this a little last night and got the scrolling waveform with an adjustable history buffer. This is more of the behavior I had in mind when I was first designing the EZPlotTypeRolling so I'm going to refactor the EZAudioPlot and EZAudioPlotGL now so you can expect it in the update for 0.0.3.

[syedhali]

Alright, I've added scrolling behavior to the EZAudioPlot and EZAudioPlotGL for iOS and OSX. All rolling plots included in the examples will now scroll instead of wipe the whole screen. You can test the master branch if you'd like - here's a gif of it in action (check the examples to see the actual speed):

[mayank4ios]

I couldn't find the scrolling behavior in EZAudio.. Can you please help me?

[mnearents]

It doesn't scroll, it just removes points from the beginning and adds them to the end so it appears to be scrolling while recordin . But when you're done recording you can't scroll back through it.

[mayank4ios]

Ok... Thanks.. :)