A file with the .pdz extension represents a file container that has been compiled by pdc. They mostly contain compiled Lua bytecode, but they can sometimes include other assets such as images or fonts. This format uses little endian byte order.
| Offset | Type | Detail |
|---|---|---|
0 |
char[12] |
Ident Playdate PDZ |
12 |
uint32 |
Flags |
| Bitmask | Detail |
|---|---|
flag & 0x40000000 |
If > 0, the data in this file is encrypted |
File encryption is (at the time of writing) only used by Catalog games' main.pdz file as a form of DRM. The encryption method isn't known.
Following the header is a list of file entries. Each entry has a header.
| Type | Detail |
|---|---|
uint8 |
Entry Flags |
uint24 |
Entry Data length |
string |
Filename as null-terminated C string |
- |
Optional null-padding if needed to align to the next multiple of 4 bytes |
If the Entry Type flag is 5 (for a .pda audio file), some additional values are included:
| Type | Detail |
|---|---|
uint24 |
Audio sample rate in Hz |
uint8 |
Audio Data Format |
| Flag | Detail |
|---|---|
flags & 0x80 |
If > 0, file entry data is compressed |
flags & 0x7F |
Entry Type |
| Flag | Detail |
|---|---|
0 |
Unknown/unused |
1 |
Compiled Lua bytecode (.luac) |
2 |
Static image (.pdi) |
3 |
Animated image (.pdt) |
4 |
Video (.pdv) |
5 |
Audio (.pda) |
6 |
Text strings (.pds) |
7 |
Font (.pft) |
The data for a given file entry is immediately after the entry's file header. If the file's compression flag is set, this will begin with a uint32 giving the decompressed size of the data, followed by zlib-compressed data.
All of the asset entries (.pdi, .pdt, .pdv, .pda, .pds, .pft), will be missing the first 16 bytes of the header, since for most of these formats this just contains a 12-byte format ident string and some compression flags. This is why .pda entries have additional header fields for the sample rate and audio format.