ddn.data.hdf5.filter

HDF5 Filter/Compression Wrapper

This module provides a D wrapper for HDF5 filter and compression operations. Filters are used to transform data during I/O operations, commonly for compression, checksumming, and data transformation.

License

BSD-3-Clause

enum SzipOption

struct Filter FilterInfo

Types 3

enumSzipOption : uint

SZIP options for compression.

ALLOW_K13 = 1Allow encoding with SZIP

CHIP = 2Use chip encoding

EC = 4Use entropy coding (EC)

NN = 32Use nearest neighbor coding (NN)

structFilterInfo

Filter information flags.

Fields

bool canEncodeWhether the filter can encode (compress) data

bool canDecodeWhether the filter can decode (decompress) data

structFilter

Static wrapper for HDF5 filter and compression operations.

This struct provides static methods for checking filter availability and convenience methods for enabling filters on dataset creation property lists.

Example:

// Check if GZIP is available
if (Filter.isAvailable(H5Z_FILTER.DEFLATE)) {
    // Enable GZIP compression on a property list
    Filter.enableGzip(dcpl, 6);
}

// Enable a compression pipeline
Filter.enableShuffle(dcpl);
Filter.enableGzip(dcpl, 6);
Filter.enableFletcher32(dcpl);

Methods

bool isAvailable(H5Z_filter_t filterId) staticChecks if a filter is available in the HDF5 library.

bool isAvailable(H5Z_FILTER filter) staticChecks if a filter is available (enum overload).

FilterInfo getInfo(H5Z_filter_t filterId) staticGets information about a filter's capabilities.

FilterInfo getInfo(H5Z_FILTER filter) staticGets information about a filter's capabilities (enum overload).

void enableGzip(hid_t plistId, uint level = 6) staticEnables GZIP (DEFLATE) compression on a dataset creation property list.

void enableSzip(hid_t plistId, uint optionsMask, uint pixelsPerBlock = 16) staticEnables SZIP compression on a dataset creation property list.

void enableShuffle(hid_t plistId) staticEnables the shuffle filter on a dataset creation property list.

void enableNbit(hid_t plistId) staticEnables the N-bit filter on a dataset creation property list.

void enableScaleOffset(hid_t plistId, H5Z_SO scaleType, int scaleFactor = 0) staticEnables the scale-offset filter on a dataset creation property list.

void enableFletcher32(hid_t plistId) staticEnables the Fletcher32 checksum filter on a dataset creation property list.

void enableStandardPipeline(hid_t plistId, uint gzipLevel = 6) staticEnables a standard compression pipeline: shuffle + gzip + fletcher32.

bool isGzipAvailable() staticChecks if GZIP compression is available.

bool isSzipAvailable() staticChecks if SZIP compression is available.

bool isShuffleAvailable() staticChecks if the shuffle filter is available.

bool isFletcher32Available() staticChecks if the Fletcher32 filter is available.