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Compression

API > API/Runtime > API/Runtime/Core

Classes

  Type Name Description
Public class FCompressedBuffer A compressed buffer stores compressed data in a self-contained format.  
Public class FCompressedBufferReader A type that stores the state needed to decompress a compressed buffer.  
Public class FCompressedBufferReaderSourceScope A type that sets the source of a reader upon construction and resets it upon destruction.  
Public struct FDecoderContext A reusable context for the compressed buffer decoder.  
Public struct LZ4_streamHC_u    
Public struct LZ4HC_CCtx_internal    

Typedefs

Name Description
ECompressedBufferCompressionLevel  
ECompressedBufferCompressor  
LZ4_byte  
LZ4_i8  
LZ4_streamHC_t  
LZ4_u16  
LZ4_u32  
LZ4HC_CCtx_internal Never ever use these definitions directly ! Declare or allocate an LZ4_streamHC_t instead.

Enums

  Type Name Description
Public enum ECompressedBufferDecompressFlags    
Public enum FOodleDataCompression::ECompressionCommonUsage OodleDataCompression : Unreal API for direct access to Oodle Data lossless data compression for manual encoding (not in Pak/iostore) NOTE : for any data that will be stored to disk, you should not be compressing it yourself! allow the pak/iostore system to choose the compressor!  
Public enum FOodleDataCompression::ECompressionLevel ECompressionLevel : Choose the Oodle Compression Level this mostly trades encode speed vs compression ratio decode speed is determined by choice of compressor (ECompressor)  
Public enum FOodleDataCompression::ECompressor ECompressor : Choose the Oodle Compressor this mostly trades decompression speed vs compression ratio encode speed is determined by ECompressionLevel , not the compressor choice.  

Functions

  Type Name Description
Public function bool Compress an arbitrary data pointer, replacing existing data.
Public function bool

FOodleCompressedArray::CompressTArray64 ( TArray64< uint8 >& OutCompressed,
const TArray64< T >& InBuffer,
FOodleDataCompression::ECompressor InCompressor,
FOodleDataCompression::ECompressionLevel InLevel
)

  
Public function bool

FOodleCompressedArray::DecompressToTArray ( TArray< T >& OutDecompressed,
TArray< uint8 > const& InCompressed
)

 Decompress to a TArray. This should be paired with CompressTArray.
Public function bool

FOodleCompressedArray::DecompressToTArray64 ( TArray64< T >& OutDecompressed,
TArray64< uint8 > const& InCompressed
)

  
Public function int32

FOodleCompressedArray::PeekSizes ( TArray< uint8 > const& InCompressed,
int32& OutCompressedSize,
int32& OutDecompressedSize
)

 Provides access to the compressed and decompressed sizes.
Public function int32

FOodleCompressedArray::PeekSizes64 ( TArray64< uint8 > const& InCompressed,
int64& OutCompressedSize,
int64& OutDecompressedSize
)

  
Public function bool  
Public function LZ4int

LZ4_compress_default ( const char* src,
char* dst,
int srcSize,
int dstCapacity
)

 LZ4_compress_default() : Compresses 'srcSize' bytes from buffer 'src' into already allocated 'dst' buffer of size 'dstCapacity'.
Public function LZ4int

LZ4_compress_destSize ( const char* src,
char* dst,
int* srcSizePtr,
int targetDstSize
)

 LZ4_compress_destSize() : Reverse the logic : compresses as much data as possible from 'src' buffer into already allocated buffer 'dst', of size >= 'targetDestSize'.
Public function LZ4int

LZ4_compress_fast ( const char* src,
char* dst,
int srcSize,
int dstCapacity,
int acceleration
)

 LZ4_compress_fast() : Same as LZ4_compress_default(), but allows selection of "acceleration" factor.
Public function LZ4int

LZ4_compress_fast_continue ( LZ4_stream_t* streamPtr,
const char* src,
char* dst,
int srcSize,
int dstCapacity,
int acceleration
)

 LZ4_compress_fast_continue() : Compress 'src' content using data from previously compressed blocks, for better compression ratio.
Public function LZ4int

LZ4_compress_fast_extState ( void* state,
const char* src,
char* dst,
int srcSize,
int dstCapacity,
int acceleration
)

  
Public function LZ4int

LZ4_compress_HC ( const char* src,
char* dst,
int srcSize,
int dstCapacity,
int compressionLevel
)

 [LZ4compress_HC()](API\Runtime\Core\Compression\LZ4_compress_HC) : Compress data from src_ into dst, using the powerful but slower "HC" algorithm.
Public function LZ4int

LZ4_compress_HC_continue ( LZ4_streamHC_t* streamHCPtr,
const char* src,
char* dst,
int srcSize,
int maxDstSize
)

  
Public function LZ4int

LZ4_compress_HC_continue_destSize ( LZ4_streamHC_t* LZ4_streamHCPtr,
const char* src,
char* dst,
int* srcSizePtr,
int targetDstSize
)

 [LZ4compress_HC_continue_destSize()](API\Runtime\Core\Compression\LZ4_compress_HC_continue_destSiz-) : v1.9.0+ Similar to LZ4_compress_HC_continue(), but will read as much data as possible from src_ to fit into targetDstSize budget.
Public function LZ4int

LZ4_compress_HC_destSize ( void* stateHC,
const char* src,
char* dst,
int* srcSizePtr,
int targetDstSize,
int compressionLevel
)

 [LZ4compress_HC_destSize()](API\Runtime\Core\Compression\LZ4_compress_HC_destSize) : v1.9.0+ Will compress as much data as possible from src_ to fit into targetDstSize budget.
Public function LZ4int

LZ4_compress_HC_extStateHC ( void* stateHC,
const char* src,
char* dst,
int srcSize,
int maxDstSize,
int compressionLevel
)

  
Public function LZ4int

LZ4_compressBound ( int inputSize
)

 LZ4_compressBound() : Provides the maximum size that LZ4 compression may output in a "worst case" scenario (input data not compressible) This function is primarily useful for memory allocation purposes (destination buffer size).
Public function LZ4LZ4_stream_t * Note about RC_INVOKED
Public function LZ4LZ4_streamDecode_t * LZ4_createStreamDecode() and LZ4_freeStreamDecode() : creation / destruction of streaming decompression tracking context.
Public function LZ4LZ4_streamHC_t * LZ4_createStreamHC() and LZ4_freeStreamHC() : These functions create and release memory for LZ4 HC streaming state.
Public function LZ4int

LZ4_decoderRingBufferSize ( int maxBlockSize
)

 LZ4_decoderRingBufferSize() : v1.8.2+ Note : in a ring buffer scenario (optional), blocks are presumed decompressed next to each other up to the moment there is not enough remaining space for next block (remainingSize < maxBlockSize), at which stage it resumes from beginning of ring buffer.
Public function LZ4int

LZ4_decompress_safe ( const char* src,
char* dst,
int compressedSize,
int dstCapacity
)

 LZ4_decompress_safe() : compressedSize : is the exact complete size of the compressed block.
Public function LZ4int

LZ4_decompress_safe_continue ( LZ4_streamDecode_t* LZ4_streamDecode,
const char* src,
char* dst,
int srcSize,
int dstCapacity
)

 LZ4decompress*_continue() : These decoding functions allow decompression of consecutive blocks in "streaming" mode.
Public function LZ4int

LZ4_decompress_safe_partial ( const char* src,
char* dst,
int srcSize,
int targetOutputSize,
int dstCapacity
)

 LZ4_decompress_safe_partial() : Decompress an LZ4 compressed block, of size 'srcSize' at position 'src', into destination buffer 'dst' of size 'dstCapacity'.
Public function LZ4int

LZ4_decompress_safe_partial_usingDict ( const char* src,
char* dst,
int compressedSize,
int targetOutputSize,
int maxOutputSize,
const char* dictStart,
int dictSize
)

  
Public function LZ4int

LZ4_decompress_safe_usingDict ( const char* src,
char* dst,
int srcSize,
int dstCapacity,
const char* dictStart,
int dictSize
)

 LZ4decompress*usingDict() : These decoding functions work the same as a combination of LZ4_setStreamDecode() followed by LZ4_decompress*_continue() They are stand-alone, and don't need an LZ4_streamDecode_t structure.
Public function LZ4int

LZ4_freeStream ( LZ4_stream_t* streamPtr
)

  
Public function LZ4int

LZ4_freeStreamDecode ( LZ4_streamDecode_t* LZ4_stream
)

  
Public function LZ4int

LZ4_freeStreamHC ( LZ4_streamHC_t* streamHCPtr
)

  
Public function LZ4LZ4_stream_t *

LZ4_initStream ( void* buffer,
size_t size
)

 LZ4_initStream() : v1.9.0+ An LZ4_stream_t structure must be initialized at least once.
Public function LZ4LZ4_streamHC_t *

LZ4_initStreamHC ( void* buffer,
size_t size
)

 LZ4_streamHC_t : This structure allows static allocation of LZ4 HC streaming state.
Public function LZ4int

LZ4_loadDict ( LZ4_stream_t* streamPtr,
const char* dictionary,
int dictSize
)

 LZ4_loadDict() : Use this function to reference a static dictionary into LZ4_stream_t.
Public function LZ4int

LZ4_loadDictHC ( LZ4_streamHC_t* streamHCPtr,
const char* dictionary,
int dictSize
)

  
Public function LZ4void

LZ4_resetStream ( LZ4_stream_t* streamPtr
)

 LZ4_resetStream() : An LZ4_stream_t structure must be initialized at least once.
Public function LZ4void

LZ4_resetStream_fast ( LZ4_stream_t* streamPtr
)

 LZ4_resetStream_fast() : v1.9.0+ Use this to prepare an LZ4_stream_t for a new chain of dependent blocks (e.g., LZ4_compress_fast_continue()).
Public function LZ4void

LZ4_resetStreamHC ( LZ4_streamHC_t* streamHCPtr,
int compressionLevel
)

 LZ4_resetStreamHC() is now replaced by LZ4_initStreamHC().
Public function LZ4void

LZ4_resetStreamHC_fast ( LZ4_streamHC_t* streamHCPtr,
int compressionLevel
)

 These functions compress data in successive blocks of any size, using previous blocks as dictionary, to improve compression ratio.
Public function LZ4int

LZ4_saveDict ( LZ4_stream_t* streamPtr,
char* safeBuffer,
int maxDictSize
)

 LZ4_saveDict() : If last 64KB data cannot be guaranteed to remain available at its current memory location, save it into a safer place (char* safeBuffer).
Public function LZ4int

LZ4_saveDictHC ( LZ4_streamHC_t* streamHCPtr,
char* safeBuffer,
int maxDictSize
)

  
Public function LZ4int

LZ4_setStreamDecode ( LZ4_streamDecode_t* LZ4_streamDecode,
const char* dictionary,
int dictSize
)

 LZ4_setStreamDecode() : An LZ4_streamDecode_t context can be allocated once and re-used multiple times.
Public function LZ4int LZ4_compress_fast_extState() : Same as LZ4_compress_fast(), using an externally allocated memory space for its state.
Public function LZ4int Note : Decompression functions are provided within "lz4.h" (BSD license)
Public function LZ4int Library version number; useful to check dll version; requires v1.3.0+
Public function LZ4const char * Library version string; useful to check dll version; requires v1.7.5+
Public function bool  
Public function ECompressedBufferDecompressFlags  
Public function ECompressedBufferDecompressFlags &  
Public function ECompressedBufferDecompressFlags  
Public function ECompressedBufferDecompressFlags &  
Public function ECompressedBufferDecompressFlags  
Public function ECompressedBufferDecompressFlags &  
Public function ECompressedBufferDecompressFlags  

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