Minecraft Legacy Save Files

Orginial Repositoryopen in new window

Base Information

The following Table gives you Important information the structure of a Save file:

NameSize (in bytes)Description
Offset(Int)0x04offset of File information
NumberOfFiles(Int)0x04Number of Files in list of File Info
Filedatavariablebytes of each file contained inside the save
FileInfovariableFilenames, offsets within save, and size in bytes of files.

File Information

NameSize (in bytes)Description
Filename0x80Endian reverse Unicode string to dictate the path of the file
Filesize(Int)0x04Size of file in bytes
Offset(Int)0x04offset of file

MCR Structure

The following Table gives you Important information the structure of a legacy edition mcr file:

NameSize (in bytes)Description
locations0x1000offsets of the chunks within the region file, as well as X,Y positioning
timestamps0x1000timestamps for the chunks found within the previous sector
chunks and unused spacevariablechunks themselves, compressed with a different format per-console.

LCE buffers

PlatformSAVEGAMEREGIONCHUNK/GRF
Xbox360XMemcompressNoneXMemcompress (+ RLE)
PS3Deflate(Algorithm)open in new window or NoneNoneDeflate(Algorithm) (+ RLE)
WiiUZlibNoneZlib (+ RLE)
PSVitaVita RLENoneZlib (+ RLE)
SwitchZlibSwitch RLEZlib (+ RLE)

Chunk Structure

The chunks on LCE utilize a different format to Java's MCR Chunks, this is the header information:

NameSize (in bytes)Description
FlagAndBuffer0x04Bit flag for RLE and an unknown value, plus 30 bits to specify the compressed buffer size
RLEUncompressedBuffer(Int)0x04Size of the buffer after RLE is performed
UncompressedBuffer(Int)0x04Size of the buffer before RLE is performed(only occurs on PS3)
Format0x02chunk format version (0xC is aquatic)
X(Int)0x04chunk X coordinate
Y(Int)0x04chunk X coordinate
LastUpdate0x08chunk Last-Updated Time
Inhabited0x08chunk Inhabited Time(Only on chunk version 8 and higher)

Chunk header flag

Within the chunk header lies a 4-byte portion of data that dictates 2 flags and the compressed chunk size.

NameSize (in bits)Description
RLE Flag1Flag for if to use RLE
Unknown Flag1It is unknown what this flag is
CompressedSize30compressed chunk size