hootvopm/README.md

# hootvopm

This script converts a [Hoot](http://snesmusic.org/hoot/v2/) memory dump into an .opm instrument pack, suitable for the VOPM VST plugin. It's an extremely rudimentary way of extracting FM instruments from games, but it works.

## Usage

`./hootopna.py -t chip_type input_file`

Output is dumped straight to stdout; redirect it to a file if you want to save it.

### Currently-supported chip types

* OPM
* OPN
* OPNA (equivalent to OPN)

## Capturing memory in hoot

* Left- and right-clicking the "driver work" area flips between available memory pages. Scrolling the wheel in this area scrolls through the current page; you can also use Ctrl-(Up/Down/PgUp/PgDn) for this purpose.
* When you see the area you need to capture, use Ctrl-C to copy it to the clipboard. This copies the entire page to the clipboard in a human-readable format, with 16 comma-separated hex bytes per line (plus a comma at the end for whatever reason, but this is ignored).
* Paste this into a file, trimming it down to get the register area of the FM sound chip. Save it as whatever.

### Tips
* Most chips (read: all of the ones currently supported by this script) have a 256-byte register area, meaning you'll need to trim it down to 16 lines.
* From what I've seen, the chip's register area almost always resides on the first page, starting either at 0x0000 or 0x0100.

## Known issues
* Since the script looks at a simple static memory dump, it has no way of capturing certain data, instead replacing it with placeholders. These include:
    * LFO data
    * Operator on/off state; all operators are considered to be in use (this *could* potentially be inferred, though)
    * Panning, though VOPM doesn't seem to use this