/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * Copyright by the Board of Trustees of the University of Illinois. * * All rights reserved. * * * * This file is part of HDF5. The full HDF5 copyright notice, including * * terms governing use, modification, and redistribution, is contained in * * the files COPYING and Copyright.html. COPYING can be found at the root * * of the source code distribution tree; Copyright.html can be found at the * * root level of an installed copy of the electronic HDF5 document set and * * is linked from the top-level documents page. It can also be found at * * http://hdf.ncsa.uiuc.edu/HDF5/doc/Copyright.html. If you do not have * * access to either file, you may request a copy from hdfhelp@ncsa.uiuc.edu. * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ /* currently this filter only handles integer datatype * does not consider fill value */ #define H5Z_PACKAGE /*suppress error about including H5Zpkg */ #include "H5private.h" /* Generic Functions */ #include "H5Eprivate.h" /* Error handling */ #include "H5MMprivate.h" /* Memory management */ #include "H5Ppublic.h" /* Property lists */ #include "H5Oprivate.h" /* Object headers */ #include "H5Tpublic.h" /* Datatype functions */ #include "H5Zpkg.h" /* Data filters */ #ifdef H5_HAVE_FILTER_SCALEOFFSET /* Struct of parameters needed for compressing/decompressing one atomic datatype */ typedef struct { size_t size; unsigned order; unsigned minbits; } parms_atomic; /* Local function prototypes */ static herr_t H5Z_can_apply_scaleoffset(hid_t dcpl_id, hid_t type_id, hid_t space_id); static herr_t H5Z_set_local_scaleoffset(hid_t dcpl_id, hid_t type_id, hid_t space_id); static size_t H5Z_filter_scaleoffset(unsigned flags, size_t cd_nelmts, const unsigned cd_values[], size_t nbytes, size_t *buf_size, void **buf); void H5Z_scaleoffset_precompress(void *data, unsigned d_nelmts, unsigned type, unsigned filavail, unsigned *minbits, unsigned long_long *minval); void H5Z_scaleoffset_postdecompress(void *data, unsigned d_nelmts, unsigned type, unsigned filavail, unsigned long_long minval); void H5Z_scaleoffset_next_byte(size_t *j, int *buf_len); void H5Z_scaleoffset_decompress_one_byte(void *data, size_t data_offset, int k, int begin_i, unsigned char *buffer, size_t *j, int *buf_len, parms_atomic p); void H5Z_scaleoffset_compress_one_byte(void *data, size_t data_offset, int k, int begin_i, unsigned char *buffer, size_t *j, int *buf_len, parms_atomic p); void H5Z_scaleoffset_decompress_one_atomic(void *data, size_t data_offset, unsigned char *buffer, size_t *j, int *buf_len, parms_atomic p); void H5Z_scaleoffset_compress_one_atomic(void *data, size_t data_offset, unsigned char *buffer, size_t *j, int *buf_len, parms_atomic p); void H5Z_scaleoffset_decompress(void *data, unsigned d_nelmts, unsigned char *buffer, parms_atomic p); void H5Z_scaleoffset_compress(void *data, unsigned d_nelmts, unsigned char *buffer, size_t buffer_size, parms_atomic p); /* This message derives from H5Z */ H5Z_class_t H5Z_SCALEOFFSET[1] = {{ H5Z_CLASS_T_VERS, /* H5Z_class_t version */ H5Z_FILTER_SCALEOFFSET, /* Filter id number */ 1, /* Assume encoder present: check before registering */ 1, /* decoder_present flag (set to true) */ "scaleoffset", /* Filter name for debugging */ H5Z_can_apply_scaleoffset, /* The "can apply" callback */ H5Z_set_local_scaleoffset, /* The "set local" callback */ H5Z_filter_scaleoffset, /* The actual filter function */ }}; /* Local macros */ #define H5Z_SCALEOFFSET_USER_NPARMS 1 /* Number of parameters that users can set */ #define H5Z_SCALEOFFSET_TOTAL_NPARMS 7 /* Total number of parameters for filter */ #define H5Z_SCALEOFFSET_PARM_MINBITS 0 /* "User" parameter for minimum number of bits */ #define H5Z_SCALEOFFSET_PARM_NELMTS 1 /* "Local" parameter for number of elements in the chunk */ #define H5Z_SCALEOFFSET_PARM_CLASS 2 /* "Local" parameter for datatype class */ #define H5Z_SCALEOFFSET_PARM_SIZE 3 /* "Local" parameter for datatype size */ #define H5Z_SCALEOFFSET_PARM_TYPE 4 /* "Local" parameter for integer types */ #define H5Z_SCALEOFFSET_PARM_ORDER 5 /* "Local" parameter for datatype byte order */ #define H5Z_SCALEOFFSET_PARM_FILAVAIL 6 /* "Local" parameter for dataset fill value existence */ #define H5Z_SCALEOFFSET_CLS_INTEGER 0 /* Integer (datatype class) */ #define H5Z_SCALEOFFSET_CLS_FLOAT 1 /* Floating point (datatype class) */ #define H5Z_SCALEOFFSET_ORDER_LE 0 /* Little endian (datatype byte order) */ #define H5Z_SCALEOFFSET_ORDER_BE 1 /* Big endian (datatype byte order) */ #define H5Z_SCALEOFFSET_FILL_UNDEFINED 0 /* Fill value is not defined */ #define H5Z_SCALEOFFSET_FILL_DEFINED 1 /* Fill value is defined */ /* Local variables */ /* can not use pfill_val now * pfill_val: pointer to buffer containing fill value of dataset fill value if is defined */ static void *pfill_val; enum H5Z_scaleoffset_type {t_uchar, t_ushort, t_uint, t_ulong, t_ulong_long, t_schar, t_short, t_int, t_long, t_long_long}; /*------------------------------------------------------------------------- * Function: H5Z_can_apply_scaleoffset * * Purpose: Check the parameters for scaleoffset compression for * validity and whether they fit a particular dataset. * * Note: * * Return: Success: Non-negative * Failure: Negative * * Programmer: Xiaowen Wu * Friday, February 4, 2005 * * Modifications: * *------------------------------------------------------------------------- */ static herr_t H5Z_can_apply_scaleoffset(hid_t UNUSED dcpl_id, hid_t type_id, hid_t UNUSED space_id) { H5T_class_t dtype_class; /* Datatype's class */ unsigned dtype_size; /* Datatype's size (in bytes) */ H5T_order_t dtype_order; /* Datatype's endianness order */ herr_t ret_value=TRUE; /* Return value */ FUNC_ENTER_NOAPI(H5Z_can_apply_scaleoffset, FAIL) /* Get datatype's class, for checking the "datatype class" */ if((dtype_class = H5Tget_class(type_id)) == H5T_NO_CLASS ) HGOTO_ERROR(H5E_PLINE, H5E_BADTYPE, FAIL, "bad datatype class") /* Get datatype's size, for checking the "datatype size" */ if((dtype_size = H5Tget_size(type_id)) == 0) HGOTO_ERROR(H5E_PLINE, H5E_BADTYPE, FAIL, "bad datatype size") /* Codes below apply to integer or floating point datatype */ if(dtype_class == H5T_INTEGER || dtype_class == H5T_FLOAT) { /* Get datatype's endianness order */ if((dtype_order = H5Tget_order(type_id)) == H5T_ORDER_ERROR) HGOTO_ERROR(H5E_PLINE, H5E_BADTYPE, FAIL, "can't retrieve datatype endianness order") /* Range check datatype's endianness order */ /* (Note: this may not handle non-atomic datatypes well) */ if(dtype_order != H5T_ORDER_LE && dtype_order != H5T_ORDER_BE) HGOTO_ERROR(H5E_PLINE, H5E_BADTYPE, FAIL, "bad datatype endianness order") } else HGOTO_ERROR(H5E_PLINE, H5E_BADTYPE, FAIL, "datatype class not supported by scaleoffset") done: FUNC_LEAVE_NOAPI(ret_value) } /* end H5Z_can_apply_scaleoffset() */ /*------------------------------------------------------------------------- * Function: H5Z_set_local_scaleoffset * * Purpose: Set the "local" dataset parameters for scaleoffset * compression. * * Return: Success: Non-negative * Failure: Negative * * Programmer: Xiaowen Wu * Friday, February 4, 2005 * * Modifications: * *------------------------------------------------------------------------- */ static herr_t H5Z_set_local_scaleoffset(hid_t dcpl_id, hid_t type_id, hid_t space_id) { unsigned flags; /* Filter flags */ size_t cd_nelmts=H5Z_SCALEOFFSET_USER_NPARMS; /* Number of filter parameters */ unsigned cd_values[H5Z_SCALEOFFSET_TOTAL_NPARMS]; /* Filter parameters */ hssize_t npoints; /* Number of points in the dataspace */ H5T_class_t dtype_class; /* Datatype's class */ H5T_order_t dtype_order; /* Datatype's endianness order */ size_t dtype_size; /* Datatype's size (in bytes) */ H5T_sign_t dtype_sign; /* Datatype's sign */ enum H5Z_scaleoffset_type type; /* Integer type */ H5D_fill_value_t status; /* Status of fill value in property list */ herr_t ret_value=SUCCEED; /* Return value */ FUNC_ENTER_NOAPI(H5Z_set_local_scaleoffset, FAIL) /* Get the filter's current parameters */ #ifdef H5_WANT_H5_V1_6_COMPAT if(H5Pget_filter_by_id(dcpl_id,H5Z_FILTER_SCALEOFFSET,&flags,&cd_nelmts,cd_values,0,NULL)<0) #else if(H5Pget_filter_by_id(dcpl_id,H5Z_FILTER_SCALEOFFSET,&flags,&cd_nelmts,cd_values,0,NULL,NULL)<0) #endif HGOTO_ERROR(H5E_PLINE, H5E_CANTGET, FAIL, "can't get scaleoffset parameters") /* Get total number of elements in the chunk */ if ((npoints=H5Sget_simple_extent_npoints(space_id))<0) HGOTO_ERROR(H5E_PLINE, H5E_CANTGET, FAIL, "unable to get number of points in the dataspace") /* Set "local" parameter for this dataset's number of elements */ H5_ASSIGN_OVERFLOW(cd_values[H5Z_SCALEOFFSET_PARM_NELMTS],npoints,hssize_t,unsigned); /* Get datatype's class */ if((dtype_class=H5Tget_class(type_id))==H5T_NO_CLASS ) HGOTO_ERROR(H5E_PLINE, H5E_BADTYPE, FAIL, "bad datatype class") /* Set "local" parameter for datatype's class */ switch(dtype_class) { case H5T_INTEGER: cd_values[H5Z_SCALEOFFSET_PARM_CLASS] = H5Z_SCALEOFFSET_CLS_INTEGER; break; case H5T_FLOAT: cd_values[H5Z_SCALEOFFSET_PARM_CLASS] = H5Z_SCALEOFFSET_CLS_FLOAT; break; default: HGOTO_ERROR(H5E_PLINE, H5E_BADTYPE, FAIL, "datatype class not supported by scaleoffset") } /* end switch */ /* Get datatype's size */ if((dtype_size=H5Tget_size(type_id))==0) HGOTO_ERROR(H5E_PLINE, H5E_BADTYPE, FAIL, "bad datatype size") /* Set "local" parameter for datatype size */ cd_values[H5Z_SCALEOFFSET_PARM_SIZE] = dtype_size; /* Get datatype's sign */ if((dtype_sign=H5Tget_sign(type_id))==H5T_SGN_ERROR) HGOTO_ERROR(H5E_PLINE, H5E_BADTYPE, FAIL, "bad datatype sign") if(dtype_class==H5T_INTEGER) { if(dtype_sign==H5T_SGN_NONE) { /* unsigned integer */ if(dtype_size == sizeof(unsigned char)) type = t_uchar; else if(dtype_size == sizeof(unsigned short)) type = t_ushort; else if(dtype_size == sizeof(unsigned int)) type = t_uint; else if(dtype_size == sizeof(unsigned long)) type = t_ulong; else if(dtype_size == sizeof(unsigned long_long)) type = t_ulong_long; else HGOTO_ERROR(H5E_PLINE, H5E_BADTYPE, FAIL, "integer size not matched") } if(dtype_sign==H5T_SGN_2) { /* signed integer */ if(dtype_size == sizeof(signed char)) type = t_schar; else if(dtype_size == sizeof(short)) type = t_short; else if(dtype_size == sizeof(int)) type = t_int; else if(dtype_size == sizeof(long)) type = t_long; else if(dtype_size == sizeof(long_long)) type = t_long_long; else HGOTO_ERROR(H5E_PLINE, H5E_BADTYPE, FAIL, "integer size not matched") } /* Set "local" parameter for integer types */ cd_values[H5Z_SCALEOFFSET_PARM_TYPE] = type; } /* Get datatype's endianness order */ if((dtype_order=H5Tget_order(type_id))==H5T_ORDER_ERROR) HGOTO_ERROR(H5E_PLINE, H5E_BADTYPE, FAIL, "bad datatype endianness order") /* Set "local" parameter for datatype endianness */ switch(dtype_order) { case H5T_ORDER_LE: /* Little-endian byte order */ cd_values[H5Z_SCALEOFFSET_PARM_ORDER] = H5Z_SCALEOFFSET_ORDER_LE; break; case H5T_ORDER_BE: /* Big-endian byte order */ cd_values[H5Z_SCALEOFFSET_PARM_ORDER] = H5Z_SCALEOFFSET_ORDER_BE; break; default: HGOTO_ERROR(H5E_PLINE, H5E_BADTYPE, FAIL, "bad datatype endianness order") } /* end switch */ /* Check whether fill value is defined for dataset */ if(H5Pfill_value_defined(dcpl_id, &status)<0) HGOTO_ERROR(H5E_PLINE, H5E_CANTGET, FAIL, "unable to determine if fill value is defined") /* Set local parameter for availability of fill value */ if(status == H5D_FILL_VALUE_UNDEFINED) cd_values[H5Z_SCALEOFFSET_PARM_FILAVAIL] = H5Z_SCALEOFFSET_FILL_UNDEFINED; else { cd_values[H5Z_SCALEOFFSET_PARM_FILAVAIL] = H5Z_SCALEOFFSET_FILL_DEFINED; #if 0 /* Get dataset fill value */ if(H5Pget_fill_value(dcpl_id, type_id, pfill_val)<0) HGOTO_ERROR(H5E_PLINE, H5E_CANTGET, FAIL, "unable to get fill value") #endif } /* Modify the filter's parameters for this dataset */ if(H5Pmodify_filter(dcpl_id, H5Z_FILTER_SCALEOFFSET, flags, H5Z_SCALEOFFSET_TOTAL_NPARMS, cd_values)<0) HGOTO_ERROR(H5E_PLINE, H5E_CANTSET, FAIL, "can't set local scaleoffset parameters") done: FUNC_LEAVE_NOAPI(ret_value) } /* end H5Z_set_local_scaleoffset() */ /*------------------------------------------------------------------------- * Function: H5Z_filter_scaleoffset * * Purpose: Implement an I/O filter for storing packed integer/float * data using scale and offset method. * * Return: Success: Size of buffer filtered * Failure: 0 * * Programmer: Xiaowen Wu * Monday, February 7, 2005 * * Modifications: * *------------------------------------------------------------------------- */ static size_t H5Z_filter_scaleoffset (unsigned flags, size_t cd_nelmts, const unsigned cd_values[], size_t nbytes, size_t *buf_size, void **buf) { size_t ret_value = 0; /* return value */ size_t size_out = 0; /* size of output buffer */ unsigned d_nelmts = 0; /* number of data elements in the chunk */ unsigned minbits = 0; /* minimum number of bits to store values */ unsigned long_long minval= 0; /* minimum value of input buffer */ unsigned char *outbuf = NULL; /* pointer to new output buffer */ parms_atomic p; /* paramters needed for compress/decompress functions */ unsigned buf_offset; /* buffer offset because of parameters stored in file */ FUNC_ENTER_NOAPI(H5Z_filter_scaleoffset, 0) /* check arguments */ if (cd_nelmts!=H5Z_SCALEOFFSET_TOTAL_NPARMS) HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, 0, "invalid scaleoffset number of paramters") /* copy a filter parameter to d_nelmts */ d_nelmts = cd_values[H5Z_SCALEOFFSET_PARM_NELMTS]; /* check and assign value to minimum number of bits if set by user */ if(cd_values[H5Z_SCALEOFFSET_PARM_MINBITS]!=0) { if(cd_values[H5Z_SCALEOFFSET_PARM_MINBITS]>cd_values[H5Z_SCALEOFFSET_PARM_SIZE]*8) HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, 0, "invalid scaleoffset minimum number of bits") minbits = cd_values[H5Z_SCALEOFFSET_PARM_MINBITS]; } /* prepare paramters to pass to compress/decompress functions */ p.size = cd_values[H5Z_SCALEOFFSET_PARM_SIZE]; p.order = cd_values[H5Z_SCALEOFFSET_PARM_ORDER]; /* input; decompress */ if (flags & H5Z_FLAG_REVERSE) { /* get values of minbits and minval from input buffer */ HDmemcpy(&minbits, *buf, sizeof(unsigned)); HDmemcpy(&minval, (unsigned char*)(*buf)+sizeof(unsigned), sizeof(unsigned long_long)); assert(minbits < p.size * 8); /* no need to process the data */ if(minbits == cd_values[H5Z_SCALEOFFSET_PARM_SIZE] * 8) { ret_value = *buf_size; goto done; } size_out = d_nelmts * p.size; /* allocate memory space for decompressed buffer */ if(NULL==(outbuf = H5MM_malloc(size_out))) HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, 0, "memory allocation failed for scaleoffset decompression") #if 0 /* the data buffer all have same value */ if(minbits == 0) { } #endif p.minbits = minbits; /* decompress the buffer */ buf_offset = sizeof(unsigned) + sizeof(unsigned long_long); H5Z_scaleoffset_decompress(outbuf, d_nelmts, (unsigned char*)(*buf)+buf_offset, p); /* postprocess after decompress */ H5Z_scaleoffset_postdecompress(outbuf, d_nelmts, cd_values[H5Z_SCALEOFFSET_PARM_TYPE], cd_values[H5Z_SCALEOFFSET_PARM_FILAVAIL], minval); } /* output; compress */ else { /* preprocess before compress */ H5Z_scaleoffset_precompress(*buf, d_nelmts, cd_values[H5Z_SCALEOFFSET_PARM_TYPE], cd_values[H5Z_SCALEOFFSET_PARM_FILAVAIL], &minbits, &minval); assert(minbits < p.size * 8); /* no need to process the data */ if(minbits == p.size * 8) { ret_value = *buf_size; goto done; } #if 0 /* the data buffer all have same value */ if(minbits == 0) { *buf_size = 0; ret_value = 0; goto done; } #endif p.minbits = minbits; /* calculate buffer size after compression, may be 1 bigger * minbits and minval are stored in the front of the compressed buffer */ size_out = nbytes * p.minbits / (p.size * 8) + 1 + sizeof(unsigned) + sizeof(unsigned long_long); /* allocate memory space for compressed buffer */ if(NULL==(outbuf = H5MM_malloc(size_out))) HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, 0, "memory allocation failed for scaleoffset compression") /* first store minbits and minval in output buffer */ HDmemcpy(outbuf, &minbits, sizeof(unsigned)); HDmemcpy(outbuf+sizeof(unsigned), &minval, sizeof(unsigned long_long)); /* compress the buffer */ buf_offset = sizeof(unsigned) + sizeof(unsigned long_long); H5Z_scaleoffset_compress(*buf, d_nelmts, outbuf+buf_offset, size_out-buf_offset, p); #if 0 printf("After compress:\n"); for(i = 0; i < size_out; i++) { printf("%02x ", ((unsigned char *)(outbuf))[i]); if((i+1)%4==0) printf("\n"); } #endif } /* free the input buffer */ H5MM_xfree(*buf); /* set return values */ *buf = outbuf; outbuf = NULL; *buf_size = size_out; ret_value = size_out; done: if(outbuf) H5MM_xfree(outbuf); FUNC_LEAVE_NOAPI(ret_value) } /* ======== Scaleoffset Algorithm =============================================== * assume one byte has 8 bit * assume padding bit is 0 * assume size of unsigned char is one byte * assume one data item of certain datatype is stored continously in bytes * atomic datatype is treated on byte basis */ void H5Z_scaleoffset_precompress(void *data, unsigned d_nelmts, unsigned type, unsigned filavail, unsigned *minbits, unsigned long_long *minval) { unsigned i; unsigned long_long span; /* span of values of input buffer data */ enum H5Z_scaleoffset_type t; /* integer type */ t = type; if(type == t_uchar) { unsigned char *buf, min, max; buf = data; min = max = buf[0]; for(i = 0; i < d_nelmts; i++) { /* find maximum and minimum values */ if(buf[i] > max) max = buf[i]; if(buf[i] < min) min = buf[i]; } span = max - min + 1; *minval = min; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] -= min; } else if(type == t_ushort) { unsigned short *buf, min, max; buf = data; min = max = buf[0]; for(i = 0; i < d_nelmts; i++) { /* find maximum and minimum values */ if(buf[i] > max) max = buf[i]; if(buf[i] < min) min = buf[i]; } span = max - min + 1; *minval = min; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] -= min; } else if(type == t_uint) { unsigned int *buf, min, max; buf = data; min = max = buf[0]; for(i = 0; i < d_nelmts; i++) { /* find maximum and minimum values */ if(buf[i] > max) max = buf[i]; if(buf[i] < min) min = buf[i]; } span = max - min + 1; *minval = min; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] -= min; } else if(type == t_ulong) { unsigned long *buf, min, max; buf = data; min = max = buf[0]; for(i = 0; i < d_nelmts; i++) { /* find maximum and minimum values */ if(buf[i] > max) max = buf[i]; if(buf[i] < min) min = buf[i]; } span = max - min + 1; *minval = min; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] -= min; } else if(type == t_ulong_long) { unsigned long_long *buf, min, max; buf = data; min = max = buf[0]; for(i = 0; i < d_nelmts; i++) { /* find maximum and minimum values */ if(buf[i] > max) max = buf[i]; if(buf[i] < min) min = buf[i]; } span = max - min + 1; *minval = min; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] -= min; } else if(type == t_schar) { signed char *buf, min, max; buf = data; min = max = buf[0]; for(i = 0; i < d_nelmts; i++) { /* find maximum and minimum values */ if(buf[i] > max) max = buf[i]; if(buf[i] < min) min = buf[i]; } span = max - min + 1; *minval = min; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] -= min; } else if(type == t_short) { short *buf, min, max; buf = data; min = max = buf[0]; for(i = 0; i < d_nelmts; i++) { /* find maximum and minimum values */ if(buf[i] > max) max = buf[i]; if(buf[i] < min) min = buf[i]; } span = max - min + 1; *minval = min; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] -= min; } else if(type == t_int) { int *buf, min, max; buf = data; min = max = buf[0]; for(i = 0; i < d_nelmts; i++) { /* find maximum and minimum values */ if(buf[i] > max) max = buf[i]; if(buf[i] < min) min = buf[i]; } span = max - min + 1; *minval = min; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] -= min; } else if(type == t_long) { long *buf, min, max; buf = data; min = max = buf[0]; for(i = 0; i < d_nelmts; i++) { /* find maximum and minimum values */ if(buf[i] > max) max = buf[i]; if(buf[i] < min) min = buf[i]; } span = max - min + 1; *minval = min; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] -= min; } else if(type == t_long_long) { long_long *buf, min, max; buf = data; min = max = buf[0]; for(i = 0; i < d_nelmts; i++) { /* find maximum and minimum values */ if(buf[i] > max) max = buf[i]; if(buf[i] < min) min = buf[i]; } span = max - min + 1; *minval = min; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] -= min; } #if 0 /* if minbits not set by application, calculate minbits */ if(*minbits == 0) { if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) *minbits = HDceil(log(span)*M_LOG2E); else *minbits = HDceil(log(span+1)*M_LOG2E); } #endif } void H5Z_scaleoffset_postdecompress(void *data, unsigned d_nelmts, unsigned type, unsigned filavail, unsigned long_long minval) { unsigned i; long_long sminval = *(long_long*)&minval; /* for signed integer types */ enum H5Z_scaleoffset_type t; /* integer type */ t = type; if(type == t_uchar) { unsigned char *buf = data; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] += minval; } else if(type == t_ushort) { unsigned short *buf = data; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] += minval; } else if(type == t_uint) { unsigned int *buf = data; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] += minval; } else if(type == t_ulong) { unsigned long *buf = data; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] += minval; } else if(type == t_ulong_long) { unsigned long_long *buf = data; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] += minval; } else if(type == t_schar) { signed char *buf = data; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] += sminval; } else if(type == t_short) { short *buf = data; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] += sminval; } else if(type == t_int) { int *buf = data; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] += sminval; } else if(type == t_long) { long *buf = data; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] += sminval; } else if(type == t_long_long) { long_long *buf = data; if(filavail == H5Z_SCALEOFFSET_FILL_UNDEFINED) for(i = 0; i < d_nelmts; i++) buf[i] += sminval; } } void H5Z_scaleoffset_next_byte(size_t *j, int *buf_len) { ++(*j); *buf_len = 8 * sizeof(unsigned char); } void H5Z_scaleoffset_decompress_one_byte(void *data, size_t data_offset, int k, int begin_i, unsigned char *buffer, size_t *j, int *buf_len, parms_atomic p) { int dat_len; /* dat_len is the number of bits to be copied in each data byte */ unsigned char val; /* value to be copied in each data byte */ /* initialize value and bits of unsigned char to be copied */ val = buffer[*j]; if(k == begin_i) dat_len = p.minbits % 8; else dat_len = 8; if(*buf_len > dat_len) { ((unsigned char *)data)[data_offset + k] = ((val >> (*buf_len - dat_len)) & ~(~0 << dat_len)); *buf_len -= dat_len; } else { ((unsigned char *)data)[data_offset + k] = ((val & ~(~0 << *buf_len)) << (dat_len - *buf_len)); dat_len -= *buf_len; H5Z_scaleoffset_next_byte(j, buf_len); if(dat_len == 0) return; val = buffer[*j]; ((unsigned char *)data)[data_offset + k] |= ((val >> (*buf_len - dat_len)) & ~(~0 << dat_len)); *buf_len -= dat_len; } } void H5Z_scaleoffset_decompress_one_atomic(void *data, size_t data_offset, unsigned char *buffer, size_t *j, int *buf_len, parms_atomic p) { /* begin_i: the index of byte having first significant bit */ int k, begin_i, dtype_len; assert(p.minbits > 0); dtype_len = p.size * 8; if(p.order == H5Z_SCALEOFFSET_ORDER_LE) { /* little endian */ begin_i = p.size - 1 - (dtype_len - p.minbits) / 8; for(k = begin_i; k >= 0; k--) H5Z_scaleoffset_decompress_one_byte(data, data_offset, k, begin_i, buffer, j, buf_len, p); } if(p.order == H5Z_SCALEOFFSET_ORDER_BE) { /* big endian */ begin_i = (dtype_len - p.minbits) / 8; for(k = begin_i; k <= p.size - 1; k++) H5Z_scaleoffset_decompress_one_byte(data, data_offset, k, begin_i, buffer, j, buf_len, p); } } void H5Z_scaleoffset_decompress(void *data, unsigned d_nelmts, unsigned char *buffer, parms_atomic p) { /* i: index of data, j: index of buffer, buf_len: number of bits to be filled in current byte */ size_t i, j; int buf_len; /* may not have to initialize to zeros */ for(i = 0; i < d_nelmts*p.size; i++) ((unsigned char *)data)[i] = 0; /* initialization before the loop */ j = 0; buf_len = sizeof(unsigned char) * 8; /* decompress */ for(i = 0; i < d_nelmts; i++) H5Z_scaleoffset_decompress_one_atomic(data, i*p.size, buffer, &j, &buf_len, p); } void H5Z_scaleoffset_compress_one_byte(void *data, size_t data_offset, int k, int begin_i, unsigned char *buffer, size_t *j, int *buf_len, parms_atomic p) { int dat_len; /* dat_len is the number of bits to be copied in each data byte */ unsigned char val; /* value to be copied in each data byte */ /* initialize value and bits of unsigned char to be copied */ val = ((unsigned char *)data)[data_offset + k]; if(k == begin_i) dat_len = p.minbits % 8; else dat_len = 8; if(*buf_len > dat_len) { buffer[*j] |= (val & ~(~0 << dat_len)) << (*buf_len - dat_len); *buf_len -= dat_len; } else { buffer[*j] |= (val >> (dat_len - *buf_len)) & ~(~0 << *buf_len); dat_len -= *buf_len; H5Z_scaleoffset_next_byte(j, buf_len); if(dat_len == 0) return; buffer[*j] = (val & ~(~0 << dat_len)) << (*buf_len - dat_len); *buf_len -= dat_len; } } void H5Z_scaleoffset_compress_one_atomic(void *data, size_t data_offset, unsigned char *buffer, size_t *j, int *buf_len, parms_atomic p) { /* begin_i: the index of byte having first significant bit */ int k, begin_i, dtype_len; assert(p.minbits > 0); dtype_len = p.size * 8; if(p.order == H5Z_SCALEOFFSET_ORDER_LE) { /* little endian */ begin_i = p.size - 1 - (dtype_len - p.minbits) / 8; for(k = begin_i; k >= 0; k--) H5Z_scaleoffset_compress_one_byte(data, data_offset, k, begin_i, buffer, j, buf_len, p); } if(p.order == H5Z_SCALEOFFSET_ORDER_BE) { /* big endian */ begin_i = (dtype_len - p.minbits) / 8; for(k = begin_i; k <= p.size - 1; k++) H5Z_scaleoffset_compress_one_byte(data, data_offset, k, begin_i, buffer, j, buf_len, p); } } void H5Z_scaleoffset_compress(void *data, unsigned d_nelmts, unsigned char *buffer, size_t buffer_size, parms_atomic p) { /* i: index of data, j: index of buffer, buf_len: number of bits to be filled in current byte */ size_t i, j; int buf_len; /* must initialize buffer to be zeros */ for(j = 0; j < buffer_size; j++) buffer[j] = 0; /* initialization before the loop */ j = 0; buf_len = sizeof(unsigned char) * 8; /* compress */ for(i = 0; i < d_nelmts; i++) H5Z_scaleoffset_compress_one_atomic(data, i*p.size, buffer, &j, &buf_len, p); } #endif /* H5_HAVE_FILTER_SCALEOFFSET */