ecatio.c File Reference

Basic IO functions for ECAT files. More...

#include "tpcclibConfig.h"
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <time.h>
#include <string.h>
#include "tpcextensions.h"
#include "tpcecat.h"

Go to the source code of this file.

Functions
int	ecatReadBlock (const char *filename, FILE *fp, const unsigned int blocknumber, unsigned char *data)
int	ecatVerifyMagic (const char *filename, FILE *fp)

Detailed Description

Basic IO functions for ECAT files.

Definition in file ecatio.c.

Function Documentation

ecatReadBlock()

int ecatReadBlock	(	const char *	filename,
		FILE *	fp,
		const unsigned int	blocknumber,
		unsigned char *	data )

Read specified data block from an ECAT file.

See also

ecatVerifyMagic

Returns

enum tpcerror (TPCERROR_OK when successful).

Parameters

filename	Name of file to open and read specified data block; file is closed after reading; enter NULL to use the file pointer (next argument) instead.
fp	File pointer of file, opened with fp=fopen(filename, "rb"), to read the specified data block from; enter NULL to open file (previous argument) locally. This function leaves the file pointer to the end of data block.
blocknumber	Block number to read; enter 0 to read the block from current file pointer position, if file pointer was given.
data	Pointer to write block data in; must be allocated for at least ECATBLKSIZE bytes.

Definition at line 23 of file ecatio.c.

  {
  if(filename==NULL && fp==NULL) return(TPCERROR_FAIL);
  if(data==NULL) return(TPCERROR_FAIL);
 
  if(fp!=NULL) { // read from given file pointer
 
    /* If block number was given, then seek the block */
    if(blocknumber>0) {
      if(fseeko(fp, (off_t)(blocknumber-1)*ECATBLKSIZE, SEEK_SET) != 0) 
        return(TPCERROR_NO_DATA);
    }
    /* Read the block */
    if(fread(data, ECATBLKSIZE, 1, fp)<1) return(TPCERROR_CANNOT_READ);
 
  } else { // read from given file name
 
    /* Open file for read */
    FILE *localfp=fopen(filename, "rb");
    if(localfp==NULL) return(TPCERROR_CANNOT_OPEN);
 
    /* If block number was given, then seek the block */
    if(blocknumber>0) {
      if(fseeko(localfp, (off_t)(blocknumber-1)*ECATBLKSIZE, SEEK_SET) != 0)
        {fclose(localfp); return(TPCERROR_NO_DATA);}
    }
    /* Read the block */
    if(fread(data, ECATBLKSIZE, 1, localfp)<1) {fclose(localfp); return(TPCERROR_CANNOT_READ);}
    fclose(localfp);
 
  }
 
  /* That's it then */
  return(TPCERROR_OK);
}

Referenced by ecatMListRead(), and ecatVerifyMagic().

ecatVerifyMagic()

int ecatVerifyMagic	(	const char *	filename,
		FILE *	fp )

Verify that given file (either file name or file pointer) appears to be ECAT file, based on the magic number.

ECAT 7 has defined magic numbers, which are checked. ECAT 6 format does not a defined magic number, therefore here the file is only checked to not indicate anything else than ECAT 6.

Returns

Returns 0 if magic number is definitely not ECAT; 7 if ECAT 7 magic number is found, and 6 if magic number does not indicate anything other than ECAT 6.

Author

Vesa Oikonen

Parameters

filename	Name of file to open and to verify for the magic number; file is closed after reading; enter NULL to use the file pointer (next argument) instead.
fp	File pointer of file to check, opened with fp=fopen(filename, "rb"); enter NULL to open file (previous argument) locally. This function rewinds the file pointer to start before and after reading the data.

Definition at line 84 of file ecatio.c.

  {
 
  /* Read the first data block (512 bytes) */
  unsigned char buf[ECATBLKSIZE];
  int ret=ecatReadBlock(filename, fp, 0, buf);
  if(fp!=NULL) rewind(fp);
  if(ret!=TPCERROR_OK) return(0);
 
  /* Check if the start matches the ECAT 7 magic numbers */
  if(strncmp((char*)buf, "MATRIX72v", 9)==0 || strncmp((char*)buf, "MATRIX7011", 10)==0) return(7);
 
  /* ECAT 6 does not have defined magic numbers, but check anyway */
  if(strncmp((char*)buf, "MATRIX6", 7)==0 || strncmp((char*)buf, "ECAT6", 5)==0) return(6);
 
  /* Check that we do NOT have DICOM magic number */
  if(strncmp((char*)buf+128, "DICM", 4)==0) return(0);
 
  /* Check that we do NOT have NIfTI magic number */
  if(strncmp((char*)buf+344, "ni1", 3)==0 || strncmp((char*)buf, "n+1", 3)==0) return(0);
 
  /* Check that we do NOT have Interfile magic number */
  if(strncmp((char*)buf, "!INTERFILE", 10)==0) return(0);
 
  /* There is no indication that this IS NOT an ECAT 6 file */
  return(6);
}