Pigiron is a command-line utility that brings unity to the world of MIDI and Open Source Control (OSC). MIDI is the protocol used to send and receive musical notes and data, usually between your computer and a synthesizer. OSC was designed to be MIDI's successor, but in many ways it was over engineered. Instead of the specific commands provided by MIDI, for example, such as note on, note off, and velocity, OSC is entirely dynamic. Applications and hardware create their own commands and publish these as a kind of API. This complexity makes it unintuitive compared to MIDI and might explain why MIDI is still so common. But OSC has become widely adopted when flexibility and power are required for cross-device communication, performance, and automation. All it really needs is a way to interact with old-school MIDI devices. Enter Pigiron.

After launching Pigiron, you find yourself within an interactive, command-driven environment. Typing help will list the various commands that are available, and each command has its own associated help document. In general, commands beginning with q (for query) will return data, such as q-midi-inputs to list which MIDI inputs are available on the system. But the main command type is an operator. An operator can be a MIDI input or output, a MIDI player, a monitor, a transposer for changing MIDI notes, or a delay, plus several more, and they process data that passes between them. These commands can be used either within the client itself or across OSC, allowing you to dynamically create MIDI and OSC chains of data and transformations. This can really help in a live situation or one where you want to use another application, such as Pure Data, to control a MIDI stream outside of its direct control. It sounds complicated, but it's not really when you start using it. We can't wait to see additional procedural operators added to the mix.

Project Website

Alongside entering commands into the interpreter or sending them over OSC, Pigiron can also run executable batch files.

PDF editor


Until recently, it was an inconvenience that you couldn't properly edit PDF documents on Linux. But it was also a seldom-required function that could usually be sidestepped by using LibreOffice or a web form. Recent events have changed this with everyone from local schools to doctors' offices wanting a PDF edited, or signed, or added to and reshuffled, all of which can be a challenge on Linux. Our PDF tools have improved – and KDE Plasma's Okular is a good example of a PDF viewer that can now do things such as annotations and filling out forms in a meaningful way – but they're still a long way from the capabilities of Adobe Acrobat. While there still isn't a tool that can do everything we need from a PDF editor, SourcePDF is something new that can fill an important editing gap.

SourcePDF can obviously load and view PDF documents, but its main "downloading and installing" benefit is that it can also merge them. Multiple PDF documents can be loaded at a time and reordered before being saved as a new single file. You can also choose to add an image or a new PDF before or after a specific page in the main document and then change the page ordering before again saving the entire view as a new PDF. Saving new documents also allows you to change the PDF compression level so that you can make larger documents more readily transferable via email or to archive. All of this is accomplished via SourcePDF's only dependency, the venerable Ghostscript. This is a platform and set of tools that are capable of high-quality output and PDD processing. Ordinarily, Ghostscript can be tricky to learn and master, especially when it comes to casual PDF use. SourcePDF has been able to hide this complexity, creating a decent viewer with some unique page and image editing and adding features that other PDF editors can't easily rival.

Project Website

While SourcePDF can't help you edit the contents of a PDF, it can help you concatenate them and insert and remove pages.

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