ITZ 2.401 - June 2009 Adjust the specifications for Sercel 428 recording system ITZ 2.400 - June 2009 Adjust the default phase limits to 7 degrees from 5 degrees. Adjust the field noise and signal to noise results graphs to be similar, for comparison purposes during start-up tests. Adjust the near-field gun analysis to avoid low frequency and spiking traces (cope with poor quality data transmitted by radio from two-boat work). ITZ 2.399 - February 2009 Add more colours for plotting. Adjust the graphing to fix array allocation bugs. ITZ 2.398 - February 2009 Add Input/Output Scorpion recording systems and Seismic Systems Sigma and DAQlink recording systems. Adjust the common mode rejection analyses so the reference level for dB is half the absolute system maximum input, following the SEG guidelines. ITZ 2.397 - December 2008 Adjust the impulse analysis and gain and phase analysis results to show additional information on amplitude and phase. Adjust the impulse analysis to give better test limits for slope and frequency. The plots show the correct applied test limits. ITZ 2.396 - October 2008 Add Progress T2 recording system. Adjust the filtering used for the nearfield bubble period calculations. Filtered mode is best - more reliable. ITZ 2.395 - August 2008 Adjust the analogue timing and amplitude analysis for pulsed signals. Adjust the distortion analysis to cope with low signal levels. Background noise levels are now reduced, but not eliminated. Adjust the gain and phase analysis to produce only 1 output graphic file with 6 graphs. ITZ 2.394 - June 2008 Adjust the near-field gun test bubble period plots. Adjust the calling routine for Sercel crossfeed to cope with calling the same file twice. Older versions corrupted the sample values. Also increase the window for the two passes in Sercel crossfeed to 1950 milliseconds. ITZ 2.393 - May 2008 Adjust the way Nearfield airgun sensor analysis and the first breaks analysis remove the DC offset and low frequency noise. ITZ 2.392 - February 2008 Add FFREQ drive frequency entry valid for common mode rejection, crossfeed isolation, distortion, gain similarity and calibrate routines, to override the automatic fundamental frequency calculations. Add BADTRA setting to set individual traces as bad so these are ignored. BADTRA is copied on the next line by the bad trace sequential number (integer). One entry required per trace, but an unlimited number can be entered. Add GOODTR setting to ignore bad traces (only those set as bad or no samples, etc) in error lists. Normal traces failing tests will still be listed. Bug fix to adjust the way user trace entries are kept in memory where the user has selected traces to process, for multiple processing. ITZ 2.391 - 31/01/2008 Add user entry for test level for pulsed timing calibration. Adjust the test limits for the Sercel 428 systems, land and marine. Adjust the frequency plot graphs for correct low frequency plot limit. This was previously fixed at 1 Hz, now accurately represents the lowest value from the FFT/DFT. ITZ 2.390 - 23/01/2008 Adjust pulsed timing calibration for better accuracy in low frequency pulsed signals. ITZ 2.389 - 19/01/2008 Adjust bubble period calculateions ITZ 2.388 - 20/12/2007 Minor bug fixes. ITZ 2.387 - 15/11/2007 Adjust XCROSSF to use median RMS as check for driven/non-driven channels, after problems with spiking channels. Add better recording system descriptions in results graphs. ITZ 2.386 - 27/10/2007 Adjust XCROSSF and XCOMREJ for low sample numbers. Adjust XDCLVL for automatic calculation of DC level and 5% tolerance. Add Sercel Sea Ray system. ITZ 2.385 - 27/10/2007 Adjust ZFUNDAM routine to analyse for the fundamantal frequency in all traces, used for the fundamental frequency to get the common mode or crossfeed levels. Adjust X1HZ routine used in many analyses. Adjust the plot numbering to avoid overlapping channel labels. ITZ 2.384 - 18/10/2007 Adjust Common Mode and Crossfeed analyses to first analyse for the fundamantal frequency in all traces, then use only the fundamental frequency to get the common mode or crossfeed levels. Adjust near field gun analyses. Improved pick of valid traces based on RMS rather than peak amplitudes. Adjust the calibration analysis from pulsed and repeated signal waveforms, used for GPS timing checks. Correct bug in MEDIANX subroutine. ITZ 2.383 - 16/06/2007 Adjust ZRESPON to output FFT values to the CSV file, for summing or other analysis. Adjust number of sample handling to cope with values over 65536 Add recording systems Sercel 428, Unite, and WesternGeco QLand and QMarine ITZ 2.382 - 12/04/2007 Major rewrite for gain and phase response (phase vales) based on sample to sample comparisons from FFT. Higher sensitivity. Previously was simple RMS phase response for all FFT samples within bandpass. Gain accuracy test adjusted for very low level signals. The gain accuracy specification is adjusted to suit low level signals so noise should not affect the results. ITZ 2.381 - 02/04/2007 Bug fix for graphing axes due to string over-runs. ITZ 2.380 - 28/03/2007 Minor bug fixes. ITZ 2.379 - 22/03/2007 Add streamer depth and source depth predicted depth lines to near-field notch response analysis. Add long-offset near field gun sensor analysis for data recorded with longer offsets between streamers and the sources, over 500m. Relative sensitivity analysis now uses average of 3 to 5 adjacent channels for channel to channel variations. ITZ 2.378 - 20/01/2007 Adjust near field gun sensor analysis. Use the average from the crossovers for bubble period. ITZ 2.377 - 5/7/2006 Correct positions for Max and Min spec lines on distribution plots. Harmonic distortion analysis now defaults to Blackman windowing. Checks introduced in SETUP for huge sample values and incorrect channel sets. This was to cope with bad SEGD and hence SEGY data files where bad headers were written. ITZ 2.376 - 9/05/2006 Minor changes to clean up displays. Correct handling for crosstalk for parameters request. Previous also ran the test analysis, rather than simply dumping the test parameters. ITZ 2.375 - 19/03/2006 Adjust the Near Field sensor response analysis NFRESP for notch to show speed of sound in water. Adjust the Near Field bubble preiod analysis NFIELD to accept NFKFAC, NFGVOL, NFPRES for gun depth calculations. If any of these variables is zero the analysis will not calculate a depth. Adjust the gain and phase analysis GAINPH and the receiver pulse analysis RECPUL (based on gain and phase response analysis) to accept user inputs (bug found). Change the results plots so these show sequential trace numbers NOT channel ID numbers - less confusing. ITZ 2.374 - 11/03/2006 Adjust the RMSOUT analysis for new NMO calculation and sample windowing. ITZ 2.373 - 14/02/2006 Adjust the CALIBRATE analysis to include FFT and estimate frequency and cycles more reliably. Change specifications for Sercel SN408 FDU's for those for the new model 2 FDU (double noise spec). Follows Sercel update of Dec 2006. ITZ 2.372 - 21/12/2005 Change the way ITZ handles zero values in trace data. Previously if any trace had zero values, this would reset the samples to use to zero. Now this is corrected so all killed traces are used/analysed. ITZ 2.371 - 15/12/2005 Adjust RMSOUT analysis for parameters to make ITA matching easier. New NMO correction calculations. IMPULSE analysis adjusted for notch filter calculations now checks each trace without fail. ITZ 2.370 - 15/11/2005 Adjust RESPONSE analysis to avoid windowing Add RESPAC for accelerometer response where the accelerometer data is integrated to provide equivalent velocity data for direct comparison with geophone data. Add FILTER for simple filter response for spectrum, phase and corner points only. Used for filter response from technical audit tests. ITZ 2.369 - 28/09/2005 Add capability to detect instability in the first samples of a harmonic distortion and common mode rejection file. Common mode rejection now uses Blackman windowing for FFT analysis to improve definition. Nearfield gun analysis plots simplified, and expected gun depth can be shown set by GUNDEP. Speed of sound in water can be varied set by WSPEED. ITZ 2.368 - 22/09/2005 ITZ version 2.368 has adjustments to the new wireline analysis including a minimal results plot option called by MCORREL or MWIREL. Correct the phase response plots. Adjust the timing estimates taken from the phase response. Adjust the way graphics plots are named so the file number format is again the same as for the CSV files, UNLESS the file number exceeds 999999. Adjust average and maximum, minimum and RMS analyses so these always return at least one value. Adjust FIELDNOISE for better response. Adjust Distortion analysis for noise floor and fundamental frequency calculations. Increase accuracy identifying the fundamental frequency and hence the harmonics. ITZ 2.367 - 05/08/2005 ITZ version 2.367 has wireline analysis. Called by CORREL or WIRELINE User must specify the files with the reference, then ground force traces (can be the same file), plus the window to use, plus the IREFTR reference trace number and IFORTR force trace number in the respective files. ITZ version 2.367 of 5th August has a bug fix for the wireline analysis from version 2.366. Version 2.366 read the selected trace number plus 1 (select reference trace 1 and trace 2 was read). Slight adjustment to plots and the median phase plus coarse timing error from the cross-correlation peak now included in the statistics at the bottom of each graphic. ITZ 2.366 - 04/08/2005 ITZ version 2.366 now defaults to ignore (set to zero) trace sample that exceed twice the recording system full-scale input. Previously this had to be selected. Note; if ITZ report spiking traces, investigate the cause! Use despik to switch off (or on again) the default despiking. Add SI Technology (Russia) MARSH LINE and BOTTOM FISH recording systems, called by MARSHLI. Marsh Line and Bottom Fish systems have the same specifications. Add wireline analysis capability. These need the user to specify the reference trace as IREFTR, the force trace as IFORTR, and the sweep length using WINDOW. ITZ 2.365 - 18/05/2005 Add rotating character to indicate processing is continuing Neafield gun sensor analysis changed so all traces are checked against a minimum of 66% of the absoute maximum signal level. Minor bug fix in similarity analysis csv text output file for amplitude and frequency derived from fourier transform. Receiver gain and phase now uses 3*specs for normal gain and phase Impulse analysis slope checks include upper slope limits as well as lower slope limits. ITZ 2.364 - 09/05/2005 Fix bug in file to file gain analysis for user set traces and default specification Adjust distribution titles and font sizes. Adjust y-axis labelling all graphs Adjust histogram widths for fewer than 120 channels to give better presentation Adjust histogram widths for distribution plots for better presentation Again adjust impulse for low cut slope and frequency plots (following the identification of problems with a sercel seal system not setting filters for the data channels) Adjust grtims1 and grtims2 to avoid first sample plotting errors ITZ 2.363 - 27/04/2005 Adjust graphics results file size and include shading for histograms Adjust handling of impulse files with zero low or high cut, to cope with possibility some channels may show some form of filtering problems where filter programming did not "take" ITZ 2.362 - 05/04/2005 Adjust file number handling for file numbers to 10^8 for results files Adjust graphics results file naming to handle large file numbers Add dmt summit recording system. Add calibr for single trace analysis of records with timing signals such as gps 1pps Adjust analogue analysis to avoid flagging traces as bad based on first cross-over timing Add switch to enable/disable spike detection for samples greater than 2*fspeak. Default is off, no despiking. ITZ 2.361 - 12/02/2005 Minor adjustment to pulse graphing, avoiding y axis values less than zero. Add new recording system input/output a-analog box for vectorseis recording Adjust impulse analysis to cope with multiple pulses Adjust windowing so this only is set by first good trace, all other traces copy this setting - presumes same signals on all channels ITZ 2.360 - 08/02/2005 Remove dongle licensing due to older versions of ITZ 2.found on bgp crews. Add parameters reply for all analysis routines, to avoid crashes in ita. Change hi-cut slope calculations to cope with attenuation at nyquist less than -36db (e.g. sn368) ITZ 2.359 - 29/10/2004 Slight corrections to impulse analysis and common mode rejection analysis ITZ 2.358 - 07/09/2004 Correct crossfeed analysis to allow for bad traces in the csv results. Results were previously incorrectly reported. ITZ 2.357 - 17/08/2004 Add dinkey dongles licensing Correct sercel crossfeed analysis graphics plot ITZ 2.356 - 04/07/2004 Add trdump for trace values to disk file for file checking. Change the way ITZ 2.seeks ffids from multiple segy files, and seeks traces. Adjust last trace user setting keyword lasttr, so errors in multiple segy files are correctly handled. Adjust low-cut and high-cut slope calculation for low sample numbers ITZ 2.355 - 13/05/2004 Remove checks for signal size from all z-type analyses (non-standard) so response tests, and audit checks, are free-sized. ITZ 2.354 - 14/03/2004 Correct slope calculations for slope points, now from -12 to -36 db. In systyp.f force comfre for sn408 to 31.25hz. Add stratavisor to systems. Alter fft and dft calculations to correct amplitudes. Now true amplitude is calulated from sqrt(sum(fft_values**2)/real(nnn2)) ITZ 2.353 - 20/02/2004 Improve phase calculations in fftngr and fftdsc so a() values displaced back one, phase not displaced. This appeared to correlate with expected results. Added remove pi into phase results within fftngr and fftdsc subroutines which improved the observed wrapping considerably. Added ztracer with dft capability (tracer or ftrace call) without rms plot but with phase plot. Found whammn windowing function did not improve imaging in small number ffts so do not use. Found of sample position memory after dcoffset calculation changes. Updated all routines to avoid loss of sample ms1mem and msmem. General tidy of csv formatting. Adjust setups so the check for peak signal>2*fspeak comes after multiply vec values by units. Use octave calculation octave=log(freq/base_freq)/log(2) for filter slopes Simplify analog skew text results Correct calculation for gaiamp db in systyp so positive rather than negative. ITZ 2.352 - 10/02/2004 Add discrete fourier transform but **very slow** can be called by fdistor fimpuls frespons fgainph fffttst Improve checking for 2**n values for fft and nnn can be up to 2**17 = mxvec Add fftfor but this is not working correctly and needs work. Better slope calculation in impulse analysis Make xrmslvl check for low signal then use noispe spec as max, 0.0 as min. In case rmslvl used for instrument noise analysis. Check zparams for new routines. Bug fix in zparams for rmslvl number of parameters ITZ 2.351 - 05/02/2004 Combined licensing for sheriff and dongle in one executable. Note - all new ITZ 2.utilities also use joint licensing. Improved error reporting by diskio. Added version reporting each call, in ITZitx, just before call ITZopn All file path strings now 250 characters (windows maximum 255 characters) ITZ 2.350 - 12/01/2004 Increased character string sizes for all file paths and names to 255 characters. This followed from problems by mick small and peter mcpherson using long strings such as c:\my documents\peter mcpherson\current client\ans another thing\what a fine mess you have got me into\1.sgy ITZ 2.349 - 03/01/2004 Added listing for failed traces added after normal text listing. User can now extract failures only. Changed geophone pulse (gain and phase) to receiver gain and phase Changed hydrophone pulse (voltage at specified time) to receiver pulse Thus any receiver tests can be run, pulsed data can use either test, sinewave data use receiver gain and phase ITZ 2.348 - 12/12/2003 Analysis names simplified to be a more accurate representation of the analysis. Gainph now is same as impulse using rms for phase over a 3db window of the spectrum - fairly robust even with ac data not simple pulse. Second plot shows 1st trace and average spectrum. ITZ 2.347 - 11/12/2003 Added channel set limiting, so only data from one selected channel set goes to the results (keyword channe, followed next line by the integer channel set id number) Use channel sets to ignore auxiliary channels or to allow multiple analyses from different streamers, one streamer result per run. Improved error checking for trace settings. ITZ 2.346 - 26/11/2003 Remove unnecessary graphs. Now only 2 main results per page with distribution of results histograms Where only one result is generated, top graph is the main results. Bottom graph is the histogram showing distribution curve for the results. Distribution histograms show test limits if these fall within the histogram. General routine set up for test limits, so these are the same for all graphs (depending on the graph type) Impulse analysis now is simpler, with 1st sheet of 3 the rms amplitude and rms phase results from within the +0 -3db bandwidth. ITZ 2.345 - 11/11/2003 Add hydroscience seamux24 recording system called by seamux2 ITZ 2.344 - 02/09/2003 Adjust field noise and geophone pulse so these use default specifications based on 20% worst-case failures. Add back chkspk1 for single limit (less than) and chkspk2 for double limit (less that err1, more than err2). Skip traces only needs the first entry - start trace - listed, and zeros for all others. All other values now use the file header but the start trace uses the user entry. ITZ 2.343 - 01/09/2003 Add sercel crossfeed analysing for crossfeed in 2 passes. 1st pass 1st 1000 samples, 2nd pass 2nd 1000 samples. ITZ 2.342 - 20/06/2003 Fix bug (another) in the start trace/skip trace routines. ITZ 2.341 - 16/04/2003 Improved rmsout no longer needs number groups per streamer. User must process individual streamers. Summary file numbered by pass. Fix bug in search first trace. All lscr1 open calls now only by ITZopn which sets the csv and wmf naming. Vlevel now automatically detects the peak, and checks the 100 ms sample after the peak. Checks for variation from median voltage level, and applies spec vlvspe default 20%. Now good for syntrak hydrophone leakage tests. Just point and shoot using defaults. Impulse unwrap now has limits to the number of iterations removing 2pi radians, so it does not get stuck in a loop. ITZ 2.340 - 25/03/2003 Nearfi for near-field hydrophone analysis. Summary files nfdpul.csv is average bubble period. Summary file nfdp2p.csv is peak to peak values. Summary files only include channels where the absolute maximum values exceed a user set level nfdlvl, default 500 millivolts. ITZ 2.339 - 17/02/2003 Colour now can be set for text as well as line colour. Fixed few small bugs in zparams and zheader. These now show the user title as well. ITZ 2.338 - 10/02/2003 Now all parameters must be set prior to calling any analysis. No parameters set on the line following an analysis Params call will dump the test parameters to param.txt file and *not* run the selected analysis. This, plus header will output text files for ita to access Header.txt is the segy header values for traces, rate, etc. So is the header data for the last file called. Use instead of an analysis call. Params.txt is the analysis parameters for the first analysis following the params keyword. Use with an analysis call. These changes made to fit ITZ 2.with ita visual basic front end. The ita visual basic front end will be the way forward. Eventually ita will not require ITZ 2.but will handle all data processing within the visual basic coding. Helpme has been updated to suit the new routines. ITZ 2.337 - 28/01/2003 Fix bug in xtiming rms check positive and negative against spec. Xspread renamed zspread as it is not a test but an analysis. Fix bug in zspread bandwidth. Add -6db -12db -18db tests and plots for bandwidth. Add zparams for ita calling routine to get current valid parameter Tidy up and remove unnecessary coding from ITZ 2.folder ITZ 2.336 - 21/01/2003 Fix bug in samples per trace from diskio. Maximum channels now 160,000. Traced added as a process routine. This dumps the trace values and fft dbamp and phase from the 1st 3 traces to traced.csv. ITZ 2.335 - 06/01/2003 Impulse analysis again uses unwrap. Needed to give correct unwrapped phase plot. Phase plot normalised for phase at max response. Seal system added to systyp ITZ 2.334 - 11/12/2002 Impulse analysis now checking for user input specifications for filter frequencies and slope. Minimum slope only checked. Unwrap removed. Small unwrap routine added into ximpulse. ITZ 2.333 - 07/12/2002 General tidy to remove old unwanted files remove filnum as unnecessary from x'files Corrected bug in xdistor where the variable l was used and reset during distortion level computations. Removed double declarations for zhead64 in xdistor and xgainca ITZ 2.332 - 29/11/2002 Removed iformat. Now graphs auto fit labelling to the size of data from ymxvl, using new subroutine kaxis. All grid lines written last, overlying the histograms. This shows the gridlines well in the case of many channels. Changed ztbclr and zeroxs names so no z files are analysis processes. All x*.f and z*.f files are now analysis processes ITZ 2.331 - 26/11/2002 Very significant update added check for excessive values in samples >abs(2*fspeak) due to bad data files from sn408 system libya. Updated setups to check for bad sample data. Also removed the box from round plots, so any bad channels in the 1st or last locations are obvious (for large channel numbers) Colour reintroduced kspen 4th value pen colour 0 = black 1 = light grey 2 = bright blue 3 = bright green 4 = bright red 5 = bright turquise 6 = bright turquise 7 = bright yellow 8 = black 9 = black 10 = black 11 = dark red 12 = dark grey 13 = dark green 14 = dark turquise 15 = dark red These only set the line colour for line charts and histograms, so only need adjusting in kuspec, grhist1, grhist2, grline1, grline2, grtims1 and grtims2. ITZ 2.330 - 23/11/2002 Cleared error in plotting routines that reset htx and htx2. This caused a major reduction in ITZ.exe file size, and speed improvement. Change xcomrej to plot suggested level for all noise but not report failures as bad channels. Fix bug in xgainph where lo and hi kept incrementing. ITZ 2.329 - 21/11/2002 Gridlines for x and y axes in all plots, with calculation of number per graph dependent on the height of the graph (y1-y0) and the factor yinc set in ITZdat. Change y axes subdivisions to make these the same for all graphs. Change graphing names from histo, linch and timser to grhist, grline, grtime. ITZ 2.328 - 21/11/2002 Dc offset now uses median, cycles, average, then reset samples to original. Removed windowing from all analyses. This improves the spectrum ITZ 2.327 - 30/10/2002 Skewed analysis updated for more accurate definition. Plots show skew from average from all crossings, plus skew from first crossing, plus rms. Impulse improved slope calculations to give better estimates of the locut slope. ITZ 2.326 - 10/10/2002 Changed the writing of cvs and wmf files so they appear last once the routine has finished. Plfail and plinfo adjusted to show total number of channels, plus channel set (more for multiple streamer sets). ITZ 2.325 - 29/09/2002 Added new routine vlevel to check voltage at a user specified time. User specifies time(ms), minimum, maximum voltages on calling the analysis. Distortion specification adjustment slowed (arbitrary values used based on observed results). Added channel sets to the listings showing streamer/line id from ivec(8) ITZ 2.324 - 20/09/2002 Zrmsout now improved uses nmo calculations. Needs 10 inputs (check helpme.txt). It also allows all data at once as long as each streamer has the same number of traces (for time start nmo adjustment). Corrected plot label errors for timing ITZ 2.323 - 03/09/2002 Included single header from master x***** file as zhead64 for plots and csv files Added line charting capability linch1 and linch2 following from histo1 and histo2, and interchangeable between these. Used in pltotting impulse slopes and frequencies clearly Added new routine timing for instance of a particular dc level as in seistronix ras24 system. Uses skewcx as in xmxskew for vexctor of level Added better faster median routine and modal routine. Modal based on median abverageing middle values for a large data set>64 items. Dcoffset now based on median rather than averaging/cycles iterations (slow) ITZ 2.322 - 25/08/2002 Added automatic help file dumping on errors if control file entry not understood, or no control file specified. Harmonic distortion automatic adjustment of spec is now less rapid (slower increase in spec limit with db down re fsrms) Gain and phase analysis improved and low frequency spec made the same as for mid/high frequency spec (no longer double). New gain and phase analysis introduced but still needs work so not call'able yet! This will use the peak amplitude point from the 1st channel (minimum 8hz to avoid noise) for phase and amlitude, plus a second check of all amplitudes in bandpass 8-80 hz. This will avoid the three windows of the original gain and phase analysis. ITZ 2.321 - 21/08/2002 Updated all csv files so these print correctly,directly to word (spaced properly). Adjusted locut and hicut slope to always try to give an estimate of the slope. Start at -3db for locut and hicut slope calculations (more in line with manufacturers). Increased the minimum frequency variation to 1.5 hz for filter frequencies, up to max of 2% of filter frequency. ITZ320 - 09/07/2002 Fix bugs in crossfeed (adjacent driven channel flagged as bad), impulse (locut slope) No unknown needed for system. User now gives the system name he desires and if not recognised, default specifications are used. User name appears in the results files rather than "unknown". ITZ319 - 06/06/2002 All analyses and also absavg, avgara, minara, maxara, median etc all now set to ignore bad traces (qtrok(i) false) It may be necessary to widen the scope for bad trace classification. Attempt to allow jumping blocks of data abandoned as too time consuming. It is better to eliminate unwanted auxiliaries using r_d2y and the ini file. ITZ318 - 12/04/2002 Add user entries for location of bytes for channel numbers and ffid Add user entry for number of channels between ticks in plots. ITZ317 - 09/04/2002 Comrej and comwid now call xcomrej only. If no freq specified, get the peak frequency from 1st trace and use this. Generally cleaned comrej and checked mathematically. Use an average of the fundamental frequency amplitude +/1 1hz. Also added a routine to check for very noisy channels which may not show in the average, following experience with sn388 in libya where bad channel was not detected. Change plots in pltpl2 to show low cut and high cut slopes Comrej does not need any parameters set on following line. ITZ316 - 21/03/2002 Add failed trace listing, on by default, as wmf graphics file. Nyquist attenuation now -60db or if less, less than 5% variation from median. ITZ315 - 05/03/2002 Noises and bnoise routines now check for fundamental frequency from fft (peak frequency of noise) Plots changed to noise, dc offset, fundamental amplitude microvolts, fundamental frequency Considered valuable to detect power supply interference. ITZ314 - 27/02/2002 Notch filter checking introduced into impulse. Lowcut filter can report zero for no low cut. Reading high and low cut filter points now checks for -3db against the median spectral amplitude ITZ313 - 09/02/2002 Nearfi analysis now added. Results to individual files and the average Of the 1st 3 cycles of the bubble pulse to a summary file nearfi.csv Calculates p-p primary, bubble, and bubble periods Impulse handling where low cut is zero corrected (graphs and reporting errors) Similarity graphs adjusted. ITZ312 - 11/01/2002 Rmsout now needs 5 variables on next line, locut, hicut, start sample 1st trace, start sample last trace, samples to use These changes to cope with seimsic data and slanted windows to pick as near the same reflectors in the data as possible. ITZ311 - 17/12/2001 Unwrap moved till after checks for relative phase response, and mod(pi) used as a check for wrapping for relative phase response. Nyquist attenuation added to ITZ.inc so it can be adjusted for systems in systyp.f Added rmsout as simple bandwidth limited rms level (for marine processing) no plot each pass creates a csv file plus all passes give final summary rmsout.csv ITZ310 - 28/11/2001 New iformat -1 added for i12 format all plots Nyquist attenuation added to normal impulse results plots ITZ309 - 24/10/2001 Phase unwrap corrected, but still dubious Phase plot added to impulp ITZ308 - 05/10/2001 Minor bug fixes ITZ307 - 17/09/2001 Minor bug fixes ITZ306 - 12/09/2001 Impulse analysis looks for the pulse peak and selects a window from peak minus 32 ms to a maximum of 2048 data points Phase analysis still ok from pulse peak only. ITZ305 - 08/09/2001 Impuls and impulp added. Phase analysis uses portion of data from pulse peak only Impulp plots phase Impuls does not plot phase ITZ304 - 24/07/2001 Changed plinfo to read system, pragn, rate and failed traces ITZ303 - 18/07/2001 Debugged xdistor, histo1, histo2 Added new definitions for ztitl64, zhead64, zylbl16, zxlbl16 Zhead64 and other strings can be passed to plot routines. ITZ302 - 11/07/2001 Noise with low pass filtering added as bnoise, needs low and high cut frequencies on calling as bnospe ITZ301 - 01/07/2001 Good but no noise analysis with low pass filtering ITZ300 - 30/06/2001 ITZ 2.version 3.00 good as of 21/5/2001 Diskio with testing for ffid, traces (data and aux), rate, samples, format *need to use these to autoset ITZ* Also Blackman windowing for bdistortion Hanning windowing for hdistortion Distortion uses zero padding to increase accuracy Impulse, stream, response, spread use padding to give better accuracy.