Macros

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Revision as of 10:35, 13 February 2013 by PeterSampson (talk | contribs) (Workflow: to remove ambiguity/inconsistency I changed "save" to "create" in "To create an audio file ...")
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Peter 12Feb13: This page is now published, though not visible (except via a link on my user pages and through Search). Please, therefore, do not edit either of the two Strawmen #2 & #3 for detailed content as they are for illustrative purposes only.
  • Peter 12Feb13:I really do prefer the top version on the Talk page where the "Examples" note div is positioned at the foot of the page.


FrenchFlagSmall.png Procesamiento en lotes Stapelverarbeitung

A Chain is a sequence of preconfigured commands in a set order (mainly effects) that can be applied automatically to projects or audio files. Any built-in or Nyquist effect shown in the Effect Menu and export commands can be added to a Chain. The two uses of Chains are for:

  • Batch processing (where many audio files are processed unattended with one or more effects then saved to a new file),
  • Effects automation (where the track or tracks in the current project are subjected to the same prescribed sequence of effects that are used for other projects, and optionally, a file exported).

See the examples below.

Peter 12Feb13: I don't like the title "Workflow" for this section. How about "Using Chains" or similar?
  • Ed 12Feb13 : A quick random search of a handful of other pages in the manual found no other page which had a section heading immediately following the intro div - I suspect there may be others though. Personally, I would just get rid of it completely but, if not, I have nothing better to offer for wordage.
  • Gale:13Feb13 "Workflow" is quite common in the Manual http://manual.audacityteam.org/man/Tutorials#workflow .
  • Ed 12Feb13 : I still think that where the section heading is not necessary as an anchor it just breaks up the flow between the intro div and the subsequent text.

Ed 12Feb13 : This opens a whole new can of worms! Compare:
http://manual.audacityteam.org/man/Sample_workflow_for_exporting_to_iTunes
with
http://manual.audacityteam.org/man/Recording_78rpm_records
Two drastically different styles used in two stylistically identical tutorials. Anyway, the one which (vaguely) this mimics stylistically (iTunes…in that it has a section header "Workflow") also has an intervening TOC (in this case quite lengthy). Take a look at that page zoomed out so that the page title and the Workflow section heading is in view - see the picture I posted on the forum. Note that in the case in which a TOC exists we use the heading as an anchor for the TOC. As an aside, once again I would like to point out that the text of the section heading is in (smaller?,) less bold font than the text of the sub-sections' headings that follow.

Workflow

Gale 11Feb13: Ed wants "If you need to edit an existing Chain or create a new one use File > Edit Chains". I like to keep the spans at the start but "First (if required) use File > Edit Chains... ..." would be OK. Ed thinks this is acceptable but not optimal. Maybe I'm coming round to Ed's view slightly.
  • Peter 12Feb13: I accordingly tweaked the wording for step-1

There are two related Chain commands in the File Menu called Edit Chains and Apply Chain. The workflow is as follows.

  1. First, use File > Edit Chains... if you need to create a new Chain or to edit an existing Chain.
    • To create an audio file as part of the Chain process, you must include a command that exports an audio file, such as ExportWAV.
  2. Second, use File > Apply Chain... to select one of the existing chains and apply it to either:
    • the project in the current window (this is essentially a method of effects automation) or
    • a selected list of external audio files (this is essentially an unattended batch processing of many individual items).
Peter 12Feb13: I have simplified the first step. The dear reader was being given far too much overcomplicated and confusing detail at too early a stage on this page - even I don't really understand the second bullet point about "MP3_56k". That level of detail really belongs on the Edit Chains page imo.
  1. First, use File > Edit Chains... to create a new Chain or to edit an existing Chain (if required).
    • To create an audio file as part of the Chain process, you must either:
      • add an Export command for 16-bit WAV, MP3, FLAC or OGG (which use any currently set "Options" for that format in the File Export Dialog ) or
      • use one or both commands to save "MP3_56k" (a low quality MP3 at 56 kbps bit rate).
Gale: Although I take the point, I changed it because your text (formerly in the intro which I think really was was too early) was incorrect. To "save an audio file as part of the Chain process", you do not have to add an Export command. You can instead save a 56k MP3. This is thus an independent MP3 preset and lets you keep the MP3 Export Options in Export File at a different bit rate.
  • Peter 12Feb13: Yes, but as Steve pointed out in the email thread the MP3_56K is actually an Export command rather than a Save command despite its unfortunate and inaccurate nomenclature; in Audacity we "Save" native file format (projects) and "Export" non-native formats (audio files). So imo the text is accurate and should stand. Further reasoning in the email thread.
  • Gale 13Feb13: Manual has to be accurate and unambiguous, whatever the contradictions in the software. If I was looking at Edit Chains in Audacity, and this page, your text makes me think that SaveMP3_56K does not save an audio file. And why you worry about this when we already had "To save... export."? I changed it to "To save an audio file as part of the Chain process, you must include a command that exports an audio file, such as ExportWAV." If you think it.s too long, feel free to excise "such as..." Also please stop using line breaks in text. It violates Consistency. Use a paragraph or a bullet, or leave it on one line.
  • Peter 13Feb13: to remove such ambiguity/inconsistency I changed "save" to "create" in "To create an audio file ..."
Examples:
  • A batch processing Chain might use Compressor to reduce the dynamic range of multiple WAV files (also normalizing them to maximum amplitude of 0 dB), then convert them to MP3 format.
  • An effects automation Chain for the current project might run:
    1. Normalize with settings of:
    2. Noise Removal
    3. Equalization (to perform the frequency adjustment)
    4. Normalize again at different settings (without offset removal, setting a final amplitude of -1 dB).

Edit Chains

Enables you to either edit, remove or rename existing Chains, or add a new Chain. The Chain can include a number of common Audacity functions and effects to be executed in any order you specify. In many cases, the parameters for each command in the Chain can be specified within the Edit Chains window.

Edit Chains dialog box
Accessed by: File > Edit Chains...

The left hand box in the dialog box (labeled Chains) Chains contains a list of already defined chains. You can define the name of a new chain and select which chain is active by using the Add, Remove and Rename buttons.

The right hand box (labeled Chain) lists the ordered sequence of commands for the chain selected in the "Chains" box on the left. Here you can add or remove commands for the selected chain, change the order in which the commands execute in the chain, or edit the parameters for some effects in the chain.

For further details see the Edit Chains page.


Apply Chain

Enables you to select a Chain and apply it to either the entirety of the current project, to a single audio file or to a group of specifically selected audio files in a single directory.

Apply Chain dialog box
Accessed by: File > Apply Chain...

The dialog window contains the list of all your current chains. Use left-click (or use the Up or Down arrow on the keyboard) to select the Chain you want to apply.

Then use the Apply to Current Project button for effects automation or the Apply to Files button to apply the selected chain to a set of files which you select (you must have a new, empty Audacity Project window open to use this option).

For more details see the Apply Chain page.