# Using Existing Audio

There are two primary ways to bring data into Ardour: recording it within a session from a live sound source or importing pre-existing audio files. This section covers the various ways to import audio into a session.

## Importing and Embedding

Importing and embedding are two different methods of using existing audio files on your computer (or network file system) within a session. They differ in one key respect:

Importing

  An existing audio file is copied to the session's sounds folder, and is converted into the session's native format (WAVE or Broadcast WAVE depending on your choice) and sample rate. At this time, no control over the conversion process is offered. If sample rate conversion is required, it will be carried out at the highest quality that Ardour can provide. This means that it can be rather slow (many minutes to import an audio file lasting a few minutes).

Embedding

  An existing audio file is used as a the source for a region, but is not copied or modified in any way.

## Supported External Audio File Formats

The list of audio file formats that Ardour can import/embed is quite long. It is based on the functionality offered by libsndfile, an excellent and widely used software library by Australian programmer Erik de Castro Lopo. As libsndfile's capabilities expand, so will Ardour's abilities to import (and export) new formats. Ogg/Vorbis (an excellent, unpatented and license free audio compression format similar to MP3) is planned for the near future. Currently, supported formats include:

- Microsoft WAV

- SGI/Apple AIFF/AIFC

- Sun AU/Snd

- Raw (headerless)

- Paris Audio File (PAF)

- Commodore IFF/SVX

- Sphere/NIST WAV

- IRCAM SF

- Creative VOC

- SoundForge W64

- GNU Octave MAT4.4

- Portable Voice Format

- Fasttracker 2 XI

- HMM Tool Kit HTK

Sample encodings supported include:

- Unsigned and signed 8, 16, 24 and 32 bit PCM

- IEEE 32 and 64 floating point

- U-LAW

- A-LAW

- IMA ADPCM

- MS ADPCM

- GSM 6.10

- G721/723 ADPCM

- 12/16/24 bit DWVW

- OK Dialogic ADPCM

- 8/16 DPCM

## Using audio files as tracks or regions?

When you want to use existing audio files in an Ardour session, the first choice you need to make is whether you want to bring the files in as tracks or as new regions. Consider the two following scenarios:

- you have an 8 track recording of existing material, with 1 audio file per track

- you have a sample library containing 500 small audio files

In the first case, your goal is probably to have 8 tracks (at least), with each track containing a single audio file. In the second case, its a lot more likely that you simply want to be able to use any of the samples easily, but do not want any tracks created as a direct result of the import/embed. It is very important that you understand this distinction: many new users think there should be a "simple" way to import existing audio without understanding that the goal of importing/embedding is not always the same.

Ardour provides two different options when importing. You can import/embed audio files as new tracks, or you can import/embed them into the region list, where they will be available as regions to put into new or existing tracks. You can also insert import/embed audio files directly into an existing track.

## How to import/embed

There are three pathways for importing/embedding an audio file into a session. One is initiated from the File menu, one is initiated from the track context menu, and one is initiated from the region list. These methods are all equivalent: they open the file import dialog. Once the dialog is open, you can choose to add new audio as new tracks, as regions in the region list, or as audio in the selected track. You can change this behavior once the dialog is opened.

If you want to import a file directly into an existing track, you must have the track selected in the editor before beginning the import.

If you use Nautilus as your file manager, you can easily import files into your project by dragging them onto the desired track, then releasing the mouse button. The file will then be embedded into your session.

## Working with Tags

A "tag" is bit of information, or metadata, that is associated with a data file. Specifically, tags are keywords or terms that you feel have some relevance to a particular soundfile. Ardour can store these tags in a seachable database so that you can quickly search for sounds based on the tags that you have assigned to them. For example you can assign the term "120bpm" to a sound, and then when you search for this tag, the file will appear in the search list. Tags are independent of the filename or anything else about the file. Tags, and the file paths that they are associated with, are stored in a file called "sfdb" in your Ardour user folder.

### Adding tags to a file

1. Select a file in the import dialog.

2. Enter the tags in the box to the right labeled "Tags".

Tags are stored when the input box loses focus, there is no reason to explicitly "save" them.

### Searching for files using tags

1. Select the "Search Tags" tab on the import dialog.

2. Enter the tag(s) to search for and press "Search".

Files which have been "tagged" with the input terms will appear in the results window. You can audition these files and apply tags to them from this window.

## Searching Freesound for soundfiles (optional)

Freesound (http://freesound.iua.upf.edu/) is an online database with thousands of soundfiles which can be freely used in many projects (visit Freesound for the exact licensing terms). Ardour has an option to download files directly from freesound directly from the import dialog. Freesound files are tagged with metadata which you can use to search for relevant sounds.

To enable the Freesound search engine inside Ardour, you must build Ardour with the option FREESOUND=yes, and you must have the "curl" library installed. This is currently optional but may later become a standard feature of Ardour.

To download files from Freesound, you must first register for a username and password on the freesound website. Enter this information into the text entry boxes, enter your tags to search for, and then click "Start Downloading". Ardour will begin downloading files, and the "Start Downloading" button will change to say "Cancel". Clicking the "Cancel" button will wait until the currently downloading file is finished, then the button will switch back to "Start Downloading". The button will also say "Start Downloading" once Ardour has downloaded all of the files that match the given tag. In the future there may be better indication of the file progress and better filtering on the filetypes that are downloaded.

If you later search for the same terms, you will see that the files appear in the list more quickly, because any files in the search set that are already downloaded won't have to be downloaded again.

Sounds that are downloaded from Freesound will automatically be given tags in Ardour that match their tags in the Freesound database. This means that once they are downloaded, Ardour can search for the local files very quickly using the "Search Tags" tab.