How can I change the meta message in a midi file?

admin: First posted on 2017 04 26

Baldur2630, 2017 04 26: How can I change the Key Signature of an entire midi file?

I load a midi song into my DAW and it always comes up in C. I want to be able to change the key signature of the entire song before I load it into my DAW OR even when I first load it, but I don't see how I can change it in Logic Pro X 10.3.

Is there any software that I can use to edit the header or meta message of the file?

mic, 2017 04 26: I may be stating things you already know, but just to be clear - the key signature meta message is just one possible meta message.

Also, you can have more than one key signature message in a file and these messages, if I am right, can occur anywhere in the file. They do not occur in the header of the file, but in the tracks of the MIDI file. This means that you cannot change the key signature message of an entire file.

BUT, if you just have one key signature message at the beginning of the file with the right key signature, that should be good enough.

You are seeing C major, most likely because your file does not have a key signature message anywhere. C major is just the default.

IN SHORT, yes, you can put a key signature message at the beginning of the file with the right key signature, or change the message if it is already there.

I am not an expert on software, but Orinj will do it. You can download a free version from this site. It has been some time since I played with MIDI on Orinj. I hope it will work for you.

P.S. The key signature message doesn't actually do anything to the sound of the file. It won't change the notes or anything. It is simply for display by hardware / software like your DAW.

Baldur2630, 2017 05 04: I downloaded Orinj. I'm using Windows 7 Enterprise, 8G BRAM

When I try to load it I get :

Could not find the main recordingbloggs.com.Orinj
Program will exit

mic, 2017 05 04: This means that when you try to run Orinj, Java doesn't start with the right working folder.

I tested all four downloads from the Software - Orinj page on this site and they work on my computer, but I am on Windows 10. I will test Windows 7 (I have Ultimate, not Enterprise), but this will take me a couple of days. I will post more later.

In the meantime, if you want to continue with this: Running Java applications on Windows 7 has this problem. The application starts in some Java working folder, like system32, instead of the application jar working folder.

(I have not tested this yet, but I will) You could try to fix this by:

1. Find where Orinj is installed (e.g., Program Folders -> Orinj).
2. Find the directory orange in that installation.
3. In this directory, there is a file called orange.jar. This is the file that should start Orinj when you double-click on it.
4. Right-click on this file and create a shortcut.
5. Right-click on the shortcut and check its Properties.
6. See where the shortcut is executed.
7. Change it to wherever the orange.jar file is.
8. Run Orinj through the shortcut.

For example, on my Windows 10 machine, the orange.jar file appears in:

C:\something\Orinj2.6.4\orange\orange.jar

My shortcut says that it should Start in:

C:\something\Orinj2.6.4\orange

Now, there are a couple of problems you can run into, if you try the above:

1. You do not have admin privileges to create the shortcut file under Program Files. Just install Orinj somewhere else or, even better, just unzip an Orinj installation from one of the zip downloads on this site. Orinj doesn't actually need to be installed to run. It can be just unzipped. You can place it anywhere.
2. You change where the shortcut starts and then Windows can't find Java. In this case, you will have to set the path to Java in your Control Panel, Environment Variables, PATH.

If you start going through this and you want to ping me, just e-mail at admin at recordingblogs.com and we can have a back and forth over e-mail. Also, I am curious whether you are running version 2 or 3 of Orinj.

mic, 2017 05 08: The solution in the previous post didn't work. We managed to replicate the problem on Windows 7 with Java 6. It turns out that this is a Java 6 issue, not a Windows 7 issue.

While it is possible to run Orinj in the command prompt and circumvent this error, we cannot run Orinj on Java 6. Orinj was compiled with Java 8 and running it under Java 6 will create other errors. (The command prompt command to run Orinj is 'java -classpath "orange.jar" recordingblogs.com.Orinj'. This command has to be from the folder orange/ of the Orinj installation, where the jar orange.jar resides).

One can upgrade to Java 7 (at least) and this issue will go away. I have also uploaded Orinj installations compiled with Java 7 and will update the Orinj page accordingly shortly. This is for those who want to run Java 7 and not 8. (Both Java 6 and 7 are no longer supported by Oracle).