Automated editing

[steve]

Topic split from http://forum.audacityteam.org/viewtopic ... 15#p232915

No one is suggesting anything other than a generic plug-in to (for example) delete five specific ranges in a selection.

I've been thinking about this and it looks like an interesting idea, though I'm uncertain if there would be much demand.

There are several approaches that could be taken:

1) Label based approach:
We already have "Edit > Labeled Audio > Cut/Delete/Split Cut/Split Delete/Copy" which can handle some editing tasks on multiple sections.
What we don't currently have is a way to "keep" the labeled sections and delete the un-labeled parts.
One way that this could be done is an indirect, but versatile solution of adding:
"Edit > Labeled Audio > Duplicate"
This solution assumes that "Truncate Silence" is enhanced to allow truncating to zero (a patch is already available for that).

Another possibility would be adding to Audacity a new "Label Track" feature:
"invert Labels"? (perhaps not the best name, but the idea is to automatically generate new region lables to replace the current labels, The new labels occupy the spaces between the old labels, up to the limit of the selection. I like the idea of this as a feature and have previously has practical cases where this feature would have been useful. It would probably not be too hard to implement, but would require a good name - any suggestions?

2) A plug-in with text input:
It would be possible for a Nyquist plug-in to have a text box into which a series of start / end times can be typed (or pasted). There is then an option to either "extract" (keep) these sections or delete these sections.
There could also be options for "Split Extract" and "Split Delete" (spaces between sections are converted to silence.

Limitations of using a Nyquist plug-in:

• It would be a lot slower than a built in effect because the data needs to be copied and re-written. (Audacity can simply move blocks of audio without processing the audio data).
• Currently Nyquist plug-ins perform audio extraction in RAM, so there would be a limit to how long the original selection could be (probably a bit less than 2 GB).
• Nyquist plug-ins do not support white space or track splits. After editing, all audio clips would be merged into one continuous track.

Regarding the last "limitation", the plug-in could also include an option to create labels from the entered text data.
I'm not sure if we already have a "labels from text input" plug-in, but there are probably a few user cases for that.


File Export based approach:
This could be an added feature to "Export Multiple".
Export Multiple happens as now, but rather than creating multiple files from multiple tracks/labeled regions, all of the sections are concatenated into one file.

[Gale Andrews]

What we don't currently have is a way to "keep" the labeled sections and delete the un-labeled parts.[...]

Another possibility would be adding to Audacity a new "Label Track" feature:
"invert Labels"? (perhaps not the best name, but the idea is to automatically generate new region lables to replace the current labels, The new labels occupy the spaces between the old labels, up to the limit of the selection. I like the idea of this as a feature and have previously has practical cases where this feature would have been useful. It would probably not be too hard to implement, but would require a good name - any suggestions?

There definitely have been votes for "invert labels" (up to nine as far as can be told).

There could be commands to select multiple label regions, to invert the selection, or to ignore specified labels.

A use case was written here:
http://wiki.audacityteam.org/wiki/Selec ... _selection .

Can't think of a better name than "Invert Labels" right now - it wouldn't mean anything to a novice though - they would have to try it to see what it does.

What would this command do with point labels - nothing?

2) A plug-in with text input:
It would be possible for a Nyquist plug-in to have a text box into which a series of start / end times can be typed (or pasted). There is then an option to either "extract" (keep) these sections or delete these sections.

This is more "one-step".

I think the "Invert Labels" is useful in its own right, though.

As ever, this would be better as a built-in item rather than Nyquist.

File Export based approach:
This could be an added feature to "Export Multiple".Export Multiple happens as now, but rather than creating multiple files from multiple tracks/labeled regions, all of the sections are concatenated into one file.

I find it confusing that Export Multiple should only produce one file.

Perhaps user should Split Delete and there should be a straight Export option to ignore white space between clips?

Perhaps Export Multiple could have an option to export regions outside the labelled ones i.e. performs the inversion. I think this is least important of the three approaches.


Gale

[steve]

What would this command do with point labels

"Invert Labels" would create a new labels that start from the end of the previous label to the start of the next label.

If the first label in the selection starts later than the start of the selection, then the first new label will be from the start of the selection to the start of the first old label.
If the final label in the selection ends before the end of the selection. then the final new label will be from the end of the last old label to the end of the selection.

tracks003.png (16.2 KiB) Viewed 4019 times

Point labels are and will be treated the same as region labels. The only difference with a point label is that the start time and end time are the same.

Similarly, if two of the original labels touch (but don't overlap), then "Invert Labels" will create a point label at the point where they meet.

The idea is that if a label track is inverted, and then inverted again, the result should be the same as the original.

Overlapping labels poses a problem. At present I'm thinking it best to treat overlapping labels as one "label region". I'll have a think about if there could be a better solution for this case.

[steve]

Overlapping labels poses a problem. At present I'm thinking it best to treat overlapping labels as one "label region". I'll have a think about if there could be a better solution for this case.

Yes I think that is the best solution.

[steve]

I find it confusing that Export Multiple should only produce one file.

The name is "Export Multiple" and it is "exporting multiple labelled regions or multiple tracks".

[Gale Andrews]

I find it confusing that Export Multiple should only produce one file.

The name is "Export Multiple" and it is "exporting multiple labelled regions or multiple tracks".

Export Multiple is under the File Menu. On opening it I see "Split files", "Name files", "Overwrite files".

I wouldn't expect to find the feature you suggest there.


Gale

[steve]

Export Multiple is under the File Menu. On opening it I see "Split files", "Name files", "Overwrite files".

I wouldn't expect to find the feature you suggest there.

"Split files ...", "Name files ...", "Overwrite files [_}","Export as one file [_]".
The final option would be very quick and easy for anyone wanting to import multiple files and export the multiple tracks as one track.

Where would you put it?

[Gale Andrews]

Thanks for the explanation of "Invert Labels".

Export Multiple is under the File Menu. On opening it I see "Split files", "Name files", "Overwrite files".

I wouldn't expect to find the feature you suggest there.

"Split files ...", "Name files ...", "Overwrite files [_}","Export as one file [_]".
The final option would be very quick and easy for anyone wanting to import multiple files and export the multiple tracks as one track.

Where would you put it?

I was thinking of a checkbox in the straight export dialogue.

As you write it above, it looks like Append-Import without actually stringing the Audacity tracks end-to-end. Is that what you mean? I think we really do want Append-Import so that it's easy to manage getting the files in from multiple folders in the required order.

I was thinking this "export-the-pieces-you-want-as-one-file" would work only on a single Audacity track (or if multiple tracks, the tracks would be mixed). The Invert Labels (if needed) and Labeled Audio commands would have made multiple clips in the track (the audio pieces we want to keep), then if we don't use Truncate Silence, we want to straight export as one file, ignoring the white space.


Gale

[steve]

As you write it above, it looks like Append-Import without actually stringing the Audacity tracks end-to-end.

More like an "append export". Yes it could be used in a similar manner, but I'd not like to concatenate 1000 .au files that way.
There is probably not a strong case for concatenating tracks now that we have Align End to End.

I was thinking of a checkbox in the straight export dialogue.

Something like:
Export labeled regions only: [_]
?

[waxcylinder]

There is probably not a strong case for concatenating tracks now that we have Align End to End.

And what a jolly useful tool Align End to End turns out to be

It's turning out to be very helpful where I need to concatenate classical works that are spread across more than one CD

Peter.