Community Forums Archive

Go Back

Subject:Audio Skimming Feature
Posted by: TheSnowMan
Date:8/21/2007 7:35:27 PM

How To Precisely Edit Audio without Looking At The Screen

Could Sound Forge be taught to do this on it's own?

This method was developed by blind people to allow precise editing simply by listening to the audio playback. However, I would think at least some sightlings would love it as well, because it allows you to turn down the lights, and concentrate on the music without having to keep staring at the screen.
It's a lovely thing, and very easy on the eyes.

This was implemented with scripts for the JAWS screen reader, but perhaps could be implemented other ways as well. It would be wonderful if it were a standard, optional behavior of Sound Forge itself.

The way it works is this. When you press a navigation key, left/right arrow or pageUp/PageDown, perhaps in conjunction with a modifier combination, the following steps are performed.

- Stop Playback() ;** space or enter key depending on mode
- Issue the navigation key to sound forge
- Start Playback()

There are context-dependent details to how this behaves, as described below. but, essentially, once you press a navigation key, the edit cursor position is modified accordingly, and playback immediately begins from the new cursor position, allowing you to hear where your cursor is located.
This is far superior to what you can do with the JKL keys. For example, you can use the pageDown and Page up keys to rapidly move through the file in large steps, looking for the beginning of a particular song in a long program. Use the zoom ratio to control the size of the steps.
Easily pre-audition a proposed cut without having to keep pressing control+k as you adjust the end points.
Or, use temporary selections to very precisely locate the leading edge of an event such as a drum hit.

Here are the details.

There are two user-controlled mode parameters which control this mechanism. The usage and enumeration of each is defined below:

UnselectedScanMode: Use this qualifier when no data is selected
ABSOLUTE: the stop command returns the cursor to the editing point,
the edit point is adjusted, and playback resumes from there.
This is best for fine-tuning an edit point.
RELATIVE: The stop command moves the edit point to the playback position.
The edit point is updated per the navigation key, then
playback resumes from the new edit point.
This mode is great for searching through the file.
BlipMode: Each nav key causes a short burst of audio, either left or
right of the new cursor position , to be played.

SelectedScanMode: Use this qualifier when data is selected
PlaySelection: The selected end point is adjusted, and the new selection is played.
** See below for a novel use of this mode.
PlayFromCursor: The chosen end point is adjusted, then playback starts
from the new en point position.
This is good for fine-tuning one of the end points.
AuditionCut: The chosen end point is adjusted, then a control+k keystroke
is issued, to hear what it would be like if you deleted the selection.
You can hear the proposed cut without having to press control+k
after each shift+arrow key press.

** PlaySelection mode:
It seems ludicrous to have a 3-minute selection play each time you press a shift+arrow key.
Indeed, that's not the most typical use of this mode.
But, suppose you want to establish an edit point which is immediately prior to a drum hit. You can use a temporary selection to establish this position as follows.
Stop playback a couple hundred milliseconds prior to the hit. Zoom in fairly tight, and start pressing shift+rightArrow.
Each time you press the key, you will hear a very tiny selection play, showing you some of the audio prior to the hit. With each tap of shift+right arrow, the small selection is extended to the right, and a longer tiny selection plays. Repeat this until you hear the selection end in the start of the drum hit. zoom in a bit, and press shift+LeftArrow until you don't hear the drum hit any more. discard the selection and, wah lah, your edit cursor is right next to the drum hit. If you want to get down to sample accuracy, zoom in adequately, and adjust accordingly.

this is a *wonderful* feature, and I really believe it should be considered as an optional mode supported within sound Forge itself.
Keep it efficient. It is critical that the arrow keys be very responsive, allowing the user to move around rapidly.

If you would like to hear an audio demo of this, contact me at the address below.

Jim snowbarger
E-mail: snowman@adiis.net
http://www.Snowmanradio.com

Go Back