Package File Format - ME3Tweaks/LegendaryExplorer GitHub Wiki
The following is the package file format for the games in the Mass Effect Legendary Edition collection.
| Offset | Data type / size | Description |
|---|---|---|
| 0x0 | 0x4 / int | Package Magic Number - 0x9E2A83C1 |
| 0x4 | 0x2 / short | Unreal version - LE1: 684, LE2: 684, LE3: 685 |
| 0x6 | 0x2 / short | Licensee version LE1: 171, LE2: 168, LE3: 205 |
| 0x8 | 0x4 / int | Full package header size (also known as 'Summary') |
| 0xC | 0x4 / int | Folder name string length - always 5 in ME games |
| 0x10 | 0x5 / char[] | Folder name 'None' (including null terminator) |
| 0x15 | 0x4 / int (bitmask) | Package flags |
| 0x19 | 0x4 / int | Name table entry count |
| 0x1D | 0x4 / int | Offset to start of name table (when decompressed) |
| 0x21 | 0x4 / int | Export entry count |
| 0x25 | 0x4 / int | Export metadata table offset (when decompressed) |
| 0x29 | 0x4 / int | Import entry count |
| 0x2D | 0x4 / int | Import metadata table offset (when decompressed) |
| 0x31 | 0x4 / int | (Not used in Mass Effect games) Dependency table offset |
| 0x35 | 0x4 / int | (Not used in Mass Effect games) ImportExport guids table offset |
| 0x39 | 0x4 / int | (Not used in Mass Effect games) Import guids table offset |
| 0x3D | 0x4 / int | (Not used in Mass Effect games) Export guids table offset |
| 0x41 | 0x4 / int | (Not used in Mass Effect games) Thumbnail table offset |
| 0x45 | 0x10 / guid | Package GUID - Used in replication |
| 0x55 | 0x4 / int | Number of package generations - always 1 in ME games |
| 0x59 | 0x4 / int | Generation[0]: Number of exports that were in the package at compile time |
| 0x5D | 0x4 / int | Generation[0]: Number of names that were in the package at compile time |
| 0x61 | 0x4 / int | Generation[0]: Number of objects under in this package at compile time (pre-cooked) |
| 0x65 | 0x4 / int | Engine version |
| 0x69 | 0x4 / int | CookedContent version |
| 0x6D | 0x4 / int | Bio Build number |
| 0x71 | 0x4 / int | Bio Branch (ID?) |
| 0x75 | 0x4 / int (compression type) | Type of compression used in this package |
| 0x79 | 0x4 / int | Number of compressed chunks to follow - once decompressed, the value will be zero |
| 0x83 | variable | List of compressed chunks. If none, skip directly to the next item |
| After compressed chunks (ACC) | 0x4 / int | Package source |
| ACC + 0x4 | 0x4 / int | Number of additional packages to cook along with this one - only used in level master files |
| ACC + 0x8 | list | List of unreal-style strings of packages this package also should cook |