Reading and writing Midi files

Subjects covered:

• The Midi file
• Exporting a Midi file
• Importing a Midi file

The file Midi

A MIDI file is a file which contains Midi information organized to form a full piece of music. It contains one or more time sequences of MIDI instructions which describe when and how the notes of the score must be played. Other information specify which instruments play, volumes, various controllers and other MIDI messages.

The MIDI file is a universal format of musical data exchange between various devices and computers. Pizzicato, as most musical software, reads and writes MIDI files (except Pizzicato Light, which does not read them). This is used to exchange music documents between Pizzicato and other musical software by going through the MIDI format.

You need to understand very well that the musical contents of a MIDI file contains only the start, the duration, the force and the pitch of each played note. It is a succession of instructions like this:

• press key n° 62 with a velocity of 105,
• wait one second,
• release key n° 62,
• press key n° 64 with a velocity of 78,
• wait 0.2 second,
• press key n° 67 with a velocity of 78,
• etc.

It is the equivalent of information sent by your musical keyboard to Pizzicato when you record a score in real time.

The graphic aspect of the score is not included in a MIDI file. Let us take a simple example to explain this difference. Let us consider the 3 following measures:

The display is quite different for each but when they are played, these 3 measures are strictly identical. The MIDI files will be the same for the three measures.

When you save a Midi file, you lose all information concerning the graphic aspect of the score. Only the data strictly necessary to play the score are recorded.

For this reason, the writing and reading of MIDI files is useful only when you must exchange files with another software. You will also find MIDI files libraries in the trade and on the Internet, and you can read them in Pizzicato.

Conversely, when you open a MIDI file, the notes found in the tracks are associated with each staff of the document. At this step, you can view them in the sequencer view and listen to them, even if the measures do not display the notes yet. To see the notes in the measures, transcribe the tracks in musical notation: select all measures and use the Transcribe item in the Edit menu.

Three formats exist for a MIDI file. Format 0 contains only one track with all notes together. Format 1 contains one or more tracks grouping all notes of a staff. Format 2 is rather rare and contains several independent sequences. Pizzicato reads and writes formats 0 and 1.

Exporting a MIDI file

• Start Pizzicato and open the Ex061.piz document. It contains the first 3 measures of a Bach score:

Listen to it and observe the way in which notes are graphically displayed. We will save it in a MIDI file. In the following section, we will open the MIDI file to transform it back into a score.

• In the File menu, select the Export MIDI file… item. The following dialog box appears:

Three choices lets you select between the full 0 format (with the notes), the 0 format with only tempo information (quite rare), or the full 1 format. The advised choice (and also the default choice) is format 1. Click Export. Pizzicato asks you a file name. Fill in Test and click Save. Pizzicato saves the MIDI file and the export is finished.

• Close this document.

Importing a MIDI file

Pizzicato Beginner and Professional only

• In the File menu, select the Import MIDI file… item. Pizzicato asks you to select a MIDI file. Select the Test.mid file and click Open. The score has 2 staves with 3 empty measures. Open the sequencer view. The notes are viewed by lines representing the contents of the tracks:

We will now transcribe the contents of the tracks into musical notation, exactly as if you had just recorded yourself these 2 Midi tracks using the keyboard. Close the sequencer view. With the selection tool, select all measures of the score. In the Edit menu, select the Transcribe item. As soon as the operation is finished, Pizzicato displays the contents of the tracks in musical notation. It is the translation of what was in the Midi file. You get a score which looks like this:

In this precise case, the main difference with the original score is the way in which beams and the stems of notes are presented. This kind of information is not present in a MIDI file and Pizzicato simply recreated them from scratch.

When you import a MIDI file and use the transcription, Pizzicato takes into account the parameters contained in the transcription options dialog box, exactly as explained in the lesson about transcription. You can then save the result using the Save item in the File menu.

Remarks :

• When you import a type 0 MIDI file (i.e. where all tracks are mixed on one track), Pizzicato separates the various instruments automatically in order to place them on different tracks. This separation is done on the basis of the MIDI channel.

• When importing a MIDI file, the instruments view is automatically filled with the data found at the beginning of the MIDI file, according to the synthesizer installed in your Midi configuration. This lets you easily modify the instruments used as well as the MIDI controllers like volume, balance… The MIDI channels are also assigned according to the contents of the track.

• If the MIDI file contains many tracks, Pizzicato Beginner will only open 16 of them and Pizzicato Light Plus will open only 8 of them.