[CinCV TNG] Fwd: to create time scaled media

Frederic Roenitz ml1 at aimvis.de
Wed Sep 13 00:00:45 CEST 2017

It works, thank you!

The limit is now somewhere between speed 150 and speed 160, before the
audio is muted.

A hint about this limit in the documentation might be a good idea.

 > but looks like high speeds may require big limits.  Speed kills.

My thoughts about sane speed limits

Taking 20KHz (20.000Hz) as the upper human audible limit and the
roughly last speed before the mute limit at speed 150:

20000Hz/150 == 133Hz

Keeping this in mind and now:

To sample something we need at least a sample rate of (a bit more
than) twice the frequency we want to sample.

We need a sample rate of 44KHz to sample up to about 22KHz

Default these days is often a sample rate of 48KHz which allows us to
sample up to 24KHz frequencies.

Taking 16Hz as the about lowest human audible frequency:

24000Hz/16Hz == 1500

would mean to have speed 1500 as the limit before the mute limit.
(Don't know, but might cause resource problems.)

Currently the last speed before the mute limit is roughly speed 150:

24000Hz/150 == 160Hz

So at speed 1 we have a range from 16Hz to 160Hz that would roughly
still be audible at speed 150.

... for now, the speed limit at speed 150 is enough for me. ;)

 >> How can I easily see which value a speed handle has? Currently I can
 >> drag it a bit and look at the status bar and guess how far I dragged
 >> it. Or I can right click -> speed -> click the fader nob. Both ways
 >> are quite complicated.

 > To see auto slider bars with more precision, set up your auto
 > as usual, and then use btn3 (rt mouse) to click one of the auto
 > keyframes on the timeline.  A popup menu will show which has
 > the auto type (speed) as the first menu item.  Click this menu
 > item, and a speed colored slider bar will appear.  You can only
 > click it once.  When you click the slider, press and hold down btn1
 > and move the slider to update the auto value.  A tooltip will show
 > the slider value.  When you release the button, the slider will be
 > deleted from the canvas, and the value will be updated.  Sadly,
 > the update is not ganged by double clicking.

This is what I described?!


 > A popup menu will show which has the auto type (speed) as the first
 > menu item.

be supplemented with an additional textfield near the "speed" menu
entry? This textfield would contain the current position as a number
(so that I can directly see it) and as a bonus: Could this textfield
be directly editable?

Example popup menu:

  speed: 1.23
  Hide keyframe type
  Delete keyframe

Thanks for autos.C, I will have a closer look at it these days

Kind greetings


More information about the Cinelerra mailing list