Audio Skimming And Scanning Modes

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:

• If playing, then stop playback.
• Move the edit cursor as indicated by the most recent arrow key press
• Start Playback at the new position.

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

Absolute Mode

Relative Mode

Blip Mode

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

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

Pre-roll to Cursor

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

Example Method for Selecting Data

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.

• Zoom in far enough that the page up and down keys make jumps of a couple seconds or less. Use page up and down to locate just prior to, or in the middle of, the word "four".
• Zoom out far enough that the left and right arrow keys make noticeable, but small steps. Repeat rightArrow. Playback will restart at the new edit position with each arrow press. Continue right arrow until playback is beginning just after the word "four".
• Now, we have the left end of our intended selection, but have not created it yet. We just want to remember this location for future use. Mark that position with the M key.
• Now, press space to start playback. Press enter just as you start to hear the word "five".
• Now use left arrow repeatedly until you think you are prior to the word "five". Be careful, you can get fooled here.
• Confirm that you are before the word "five" using a temporary selection. Press shift+left arrow to begin a selection, and perhaps repeat it a few times to extend to the left. When the selection plays, you should not hear any portion of the word "five". If you do, then press the end key to move to the right end of the selection, and then use shift+left arrow to drag that end point to the left until you don't hear any part of the word "five". Note that it is possible to cdrag that point so far to the left that it crosses over the other end point, in which case you will actually be editing the left end of the selection instead of the right. To avoid that, I usually begin the selection by dragging it's left end far enough left to touch the clearing of the throat, then back to the right again, just enough to avoid it. The goal is to establish a temporary selection that resides between the end of the throat clearing, and the start of the word "five". When that selection plays, you dont' hear much of anything, and the last key you press should be the home key, which puts your cursor at the left end.
• Now we have a small temporary selection, which was used only to find the very first trace of the word "five", and our cursor is at it's left end. To extend this selection clear back to the end of the previous word, we can take advantage of our maarker, and simply press control+shift+leftArrow to extend the selection back to that point. Now, space bar should confirm that our selection contains only the offending passage, so we can delete it, ir mute it, or perform whatever operation we want. Note that, just deleting it might alter the cadence of the counting, so, you might actually want to switch to audition cut mode, with control+windows+f11 to hear how a deletion will sound. If the timing is too irregular, you can then fine-tune the end points to see if a mor normal cadence can be established by shortening the selection. If that can't be done without picking up some of the offending passage, it may be necessary to perform the deletion anyway, and then insert silence to correct the timing. One of the most common editing mistakes is to cut things too close, creating artificially short and unnatural timing. Be mindful of that, and preserve the natural cadence of things.

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

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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