Sound Forge 11.0 Scripts for JAWS For Windows

Audio Skimming And Scanning Modes

When you use the arrow keys to skim through an audio file, there is a small hand full of modes you can set which control exactly how that skimming feature behaves. Some are good for precise editing, while others lend themselves more to skimming through a file to explore it's contents. Understanding how these modes work will help when attempting to select a portion of the data on which you wish to operate.

To select audio, while playing, you can press the "i" and "O" keys at points representing the start and end of the selection. Or, you can use the standard windows keys, using shift in combination with the arrow keys, including the page up and down. We'll discuss selection in more detail later. But, for now, let's discuss the scanning feature assuming that no data is selected.

For purposes of this discussion, think of two seperate cursors. One is the editing cursor. GIt identifies the point where new data will be inserted, or when an operation can be performed. You control the position of the edit cursor with your arrow keys, and that position indicates the point at which you want to perform your action.
The second cursor is the playback cursor. When not playing, the playback cursor is located at the edit cursor position. While the file is playing, the playback cursor is moving through the file, and indicates the position of the audio you are hearing. But, while playing, the edit cursor is still parked back at the point where playback begins. Much of this discussion revolves around what the playback cursor does when you stop playback through various means.

In general terms, when you operate the arrow keys, the scripts perform the following actions:

Not mentioned here yet, are some subtle differences that also get imposed depending on which scanning mode is selected. Those modes are selected by holding down control+windows, and pressing one of the keys f9 through f12.

Scanning Off

Control+windows+f12
When scanning is off, the arrow keys move the edit cursor, but do not start the playback. So, you will not hear any sound. You must press the space bar to start the playback at the new position. This mode is handy if you are looking at the Braille display, watching time change as you navigate, and do not want Sound Forge to start playing, and thus change the time while you are reading it. This is also handy if you are selecting, and are using shift+arrow keys to fine-tune a selection length. Having automatic playback disabled lets you more precisely control the time displayed.

Absolute Mode

This is the preferred mode for precise editing, where you want to focus on a particular location in the file. In absolute mode, your cursor keys control the edit cursor, which is an anchor point that is moved through the file. No matter how long you let the file play, the anchor point is not moved unless you operate the cursor keys. So, if you strike a right arrow, the edit cursor will move forward by a small amount, and playback will restart at the new edit cursor location. If you let the file play for a minute, then hit the right arrow key again, the original anchor point will be moved by the amount set by the zoom ratio, and playback will jump clear back to the new anchor point. This mode is best for detailed editing, because the amount of time you allow the file to play does not affect the position of the anchor point. However, if you are just browsing the file, playing and skimming around, this mode will not be your preferred mode, because striking an arrow key after the file has been playing for a long time, will suddenly cause playback to restart at a much earlier location, specifically, the position of the anchor point. If you want to move the anchor point to the current playback position, press the enter key while the file is playing.

Relative Mode

Relative mode, on the other hand, allows playback to move the anchor point as the file plays. So, cursor keys move the start of playback relative to the currently playing position. This mode is best for just skimming through the file looking for a particular passage. But, it is not good for detailed editing, because the anchor point is moved by the playback operation.Specifically, while the file is playing, press the left arrow or page up to move back a little bit, or the right arrow or page down to move forward a bit relative to the presently playing position. Press down arrow to increase the zoom ratio if you want to make larger jumps.

Blip Mode

Blip Mode, is similar to absolute mode and, again, is useful in detailed editing, but when you do not have any data selected. In Blip Mode, when you strike an arrow key, the scripts move the edit cursor by an amount controlled by the zoom ratio, and select the small region between the previous anchor point, and the new anchor point. The selected region is then played. So, you will hear just a short burst of audio each time you press an arrow key. In our example using the left arrow key, the cursor is actually at the left end of the small selection. If you press left arrow again, the small region is dragged to the left by an amount controlled by the zoom ratio, the new selection is played, and the cursor is again at the left side of the new selection. If you press a right arrow, the selection will not be moved, but the cursor will jump to the right end of the selection, and the same selection will be played. A second right arrow drags the selection to the right by the same amount, and the new selection is played. the cursor is now positioned at the right end of the selection.

The purpose of blip mode is to provide a less distracting way to do detailed editing since the playback does not run away from the area of interest. The disadvantage is that, if you decrease the zoom ratio to a very small value using the up arrow key, the amount of movement becomes very small. As a result, the burst of audio becomes very short, and may or may not be useful depending on your skill level and what you are doing. It is not presently possible to maintain the duration of the audio blip independent of the zoom ratio.

You can control the zoom ratio using the up and down arrows. This will cause sound forge to move in larger steps with higher zoom ratios, and smaller steps with smaller ratios. The duration of the blip played is also a function of the zoom ratio. Typically, you lower the zoom ratio using the UpArrow key when you want to make finer adjustments to the cursor position. You increase the zoom ratio with the DownArrow key when you want to make larger movements with each press of the left or right arrow keys.

In Sound Forge 11, there is a big difference between the action you get with left/right arrow, and what you get with page up and page down, in terms of how far those actions move you through the file. Some times, you end up zooming all the way out, in irder to get your arrow keys to be more responseive. But, if you want to make larger jumpts, the choice is to press lots of left/right arrow keys, or to zoom in a ways, and then use page up and page down. If you don't zoom in first, then page up and page down move in huge chunks, which generally leaves the neighborhood of where you were working. With very short files, the zoom ratio is limited such that the left and right arrow keys move in exceedingly small increments, causing you to wonder if they are actually doing anything at all. The inability to zoom out very far in small files imposes a navigational constraint, and you might need to use page up and down to make more than the finest of movements.

Tip: you can turn on loop playback with the Q key while in blip mode, and sound forge will repeatedly play the small selection. This can sometimes give a better view of the adjustments you are making.

If you have data selected, and attempt to use blip mode while pressing the shift arrow keys, the scripts will revert to absolute mode. This is because blip mode makes use of a temporary selection which can not be established without redefining your selection.

When you exit blip mode, if you press the space bar, you will usually find that data is still selected due to the way blip mode is implemented. This selection will be cleared when you operate the arrow keys, or you can press the s key to undo the selection.

Selecting Audio

There are several ways to select audio. While playing, you can press the "I" and "O" keys to mark the start and end of the selection.Or, you can use the standard windows conventions, using the shift key in conjunction with the arrow keys, the home and end keys, or the page up and page down keys. When you use the shift key, the anchor point is moved, and audio from the old anchor point to the new anchor point is selected, in addition to any audio that was already selected. So, you are extending or shrinking the selection.

When data is selected, you can telll the scripts to either play the selection, pre-roll to cursor, or audition a cut. Use alt+windows modifiers , in conjunction with f9, f10 and f11 to select the desired selection mode.

When data is selected, pressing the space bar will honor the rules established by the selection mode you have chosen, as define dbelow. Use home and end keys without a modifier, to indicate which end of the selection you want to alter. Then, use shift+left/right arrow to drag that selection end point in either direction. With each press, the selection is updated, and the new selection is played. You can always tap space bar to stop playback. Use Alt+control+t to hear the start and end times of the selection, or shift+alt+t to hear the length of the selection.

If you have a braille display, the length of the selection is displayed in less than and greater than signs..

Play Selection

alt+windows+f9. In this mode the selected region is played.

Pre-roll to Cursor

alt+windows+f10.
This mode is used to verify the right end of a selection. It plays a small portion of the selection from the back end, or the far right end of the selection, right up to the stopping point. The amount of audio played is control by the pre-roll to cursor setting in sound forge. The way to use this feature is, if you were selecting data right up to, but not including some audible event, you would be listening to the final portion of the selection, and adjusting the right end until you hearrd the start of the terminating event. then, you would use shift+left arrow to shorten the selection just enough to avoid that event.

In previous versions, this mode started playback at the right end of the selection,and then played on toward the future. But, with SF10, that became no longer possible, and pre-roll to cursor is the only option that remains.

Audition Cut

Alt+Windows+f11
This mode is great for hearing what it would sound like if you deleted the current selection. Control+k will also do this. A small portion of audio before, and another small portion of audio after the selection will be played, skipping the selected data. Each press of a Shift+arrow key will adjust the selection, then do control+k to audition the proposed cut. so, you can easily hear what it will sound like if you perform that delete with the selection end points at their current location. this allows you to adjust your endpoints for that perfect, seamless cut.

Example Method for Selecting Data

Because the "I" and "O" method is not the most precise method for selectin data, here is the Snowman's way of doing it. Describing this step by step makes it sound complicated. But, once you get the hang of it, it's not as bad as it sounds, and can produce top-quality, precise edits.

We have an audio file in which somebody is counting. Between the word "four" and "five" they cleared their throat, and we want to take that out.

It is true that we could have used a selection that started after the word "four" and just adjusted the right end. But, while that would work, it would require us to listen to the offending passage over and over as we adjusted the end points. This short selection avoided that. And, that would have been far less handy if the offending passage was several minutes long. In such a case, using pre-roll to cursor mode, control+windows+f10 might also work. But, the amount of audio that would play would be controlled by the sound forge pre-roll to cursor time, and still might have exposed us to throat clearing. Doing it the way we did allowed us to define a nice quiet selection for adjusting.

After this operation that temporary marker will still exist. Use control left or right arrow to move there, and stop playback. Now, delete the marker with alt+shift+m. It's always good to clean up after yourself.

Caveats

We already mentioned that you can drag one end of a selection so far that it crosses over the other end point, so that you are now acctually dragging the other end. It is like the selection gets flipped over. If you happen to land exactly on the other end point, the selection disappears completely. But, as you alter the zoom ratio, and continue dragging, you can create situations where those two points never land on one another, and this crossing of end points will occur without you being told.

With Sound forge 11, we have seen cases where control+left and right arrow stop moving to markers. So far, there is no clue as to why this happens. Try restarting JAWS, which may or may not help.

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