> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sampler.meiji.industries/llms.txt
> Use this file to discover all available pages before exploring further.

# File Formats

> Reference for the main file types Meiji Sampler reads, writes, caches, and recovers.

# File formats

This page covers the main file types you are likely to encounter while using Meiji Sampler.

## Sample input formats

These are the documented sample formats for import, preview, assignment, chop, and trim:

* `WAV`
* `AIFF`
* `AIFF-C`
* `MP3`
* `AAC`
* `M4A`
* `FLAC`
* `OGG`
* `ALAC`
* `CAF`

## Project format

Saved projects use the `.meiji` extension.

| Property               | Value                                                                           |
| ---------------------- | ------------------------------------------------------------------------------- |
| Format                 | JSON-based project file                                                         |
| Extension              | `.meiji`                                                                        |
| Current format version | `1`                                                                             |
| Stores                 | project metadata, session state, timing, mixer state, and related workflow data |

Project files are the durable save format. If a session matters, save a `.meiji` file instead of relying only on the last-open session state.

## Bounce/export output

The bounce flow writes:

* `WAV` files for audio export at a configurable bit depth (16-bit, 24-bit, or 32-bit float)
* optional `MP4` visualizer videos when video generation is enabled

| Bit depth        | Sample format  | Bytes per sample per channel |
| ---------------- | -------------- | ---------------------------- |
| 16-bit           | Signed integer | 2                            |
| 24-bit (default) | Signed integer | 3                            |
| 32-bit float     | IEEE 754       | 4                            |

## Recording output

Direct audio recording writes `WAV` files to the recordings directory.

## Backup files

The persistence layer uses `.bak` sibling files for recovery when appropriate.

This applies to:

* session state
* settings
* auth state
* project files

## Quick reference by artifact

| Artifact          | Format                                                                     |
| ----------------- | -------------------------------------------------------------------------- |
| Imported sample   | `WAV`, `AIFF`, `AIFF-C`, `MP3`, `AAC`, `M4A`, `FLAC`, `OGG`, `ALAC`, `CAF` |
| Saved project     | `.meiji`                                                                   |
| Recorded take     | `WAV`                                                                      |
| Audio bounce      | `WAV` (16-bit, 24-bit, or 32-bit float)                                    |
| Visualizer bounce | `MP4`                                                                      |
| Recovery backup   | `.bak`                                                                     |

## Related pages

* [Storage Paths And Project Structure](/reference/storage-paths-and-project-structure)
* [Supported Audio Formats](/reference/supported-audio-formats)