#include <nitro/mi/uncomp_stream.h>
typedef struct { u8* destp; // 4B s32 destCount; // 4B u8* treep; // 4B u32 srcTmp; // 4B u32 destTmp; // 4B s16 treeSize; // 2B u8 srcTmpCnt; // 1B u8 destTmpCnt; // 1B u8 bitSize; // 1B u8 _padding2[3]; // 3B u8 tree[0x200]; // 512B // Total 540B } MIUncompContextHuffman;
This is the context structure for saving the state of data uncompression when Huffman-compressed data is being read from the Card and undergoing streaming uncompression. The context is initialized by the MI_InitUncompContextHuffman function and used by the MI_ReadUncompHuffman function to save the uncompressed state.
If the compressed data is 4-bit encoded data, there will not be any problems if the tree member's array size is 32 bytes, so it is OK to provide a region that is 480 bytes smaller than sizeof( MIUncompContextHufffman )
If the compressed data is 8-bit encoded data you need 512 bytes, so you cannot trim the size of the structure.
| destp | Pointer to region where uncompressed data will be written |
| destCount | Remaining write size |
| treep | For storing Huffman encoding table, current pointer |
| srcTmp | For storing data while reading |
| destTmp | For storing data while writing |
| treeSize | For storing the size of the Huffman encoding table |
| srcTmpCnt | For storing data size while reading |
| destTmpCnt | For storing data size while writing |
| bitSize | Encoded bit size |
| tree | Buffer for reading Huffman encoding table |
MI_InitUncompContextHuffman
MI_ReadUncompHuffman
MIUncompContextLZ
MIUncompContextRL
2004/11/30 Initial version.
CONFIDENTIAL