Hi Juan,
I think you're right, it's probabaly related to the float samples of your file instead of older geometrics which used integers.
Included, you'll find a modified seg2segy that we use to read DMT seg2 (float samples). I succesfully read your seg2file (it seems) with it.
You must compile it in 32 bits mode On my Ubuntu box, I use gcc -m32 -o seg2segy seg2segy.c It also needs gcc-multilib to link proprely.
You also need to put the segykew.ord file somewhere (for me it's /usr/local/bin, the code uses the PATH to find it). seg2 format, unlike seg-y, is complicated and the header keywords are user (manufacturer) defined. That's the use of the segykeyw.ord file, a kind of dictionary to translate seg2 keywords into seg-y ones.
I hope that it will help.
By the way, seg2segy is the grand son (male ?) of a MS-DOS code by Bennett, modified by Hervé Perroud (a former colleague in Pau, now retired) and others. It clearly needs some update and cleaning... If anyone is interested in this work, he/she is welcome !
D.
Le 29/09/2020 à 17:51, Juan Lorenzo a écrit :
Dear Sunix users:
Do you have any advice on the correct use of seg2segy? What am I not understanding? Any words of wisdom would be most helpful. Thanks in advance, Juan
PROBLEM I am having difficulty converting SEG2 formatted files into SEGY and SU files.
INSTRUCTIONS: seg2segy 2.dat 1 > 2.sgy (BAD) segyread tape=2.sgy >2.su (BAD)
suximage < 2.su & (BAD) suximage < 2_clean.su (GOOD)
VISUAL RESULTS Screenshot shows GOOD on left and BAD on right
SYSTEMS and SOFTWARE USED cwp_su_all_44R4 CentOS8 linux box cygwin (64) on Windows10.
FILES ATTACHED 2.dat (a SEG2 file from a Geometrics box) 2.sgy, 2.su 2_clean.su Screenshot in png format of suximage-generated plots.
NOTES: -For reference, I converted a test file (2.dat) successfully from SEG2 to SU format using sioseis under CentOS8 This "GOOD" file is 2_clean.su
-"BAD" means that I am able to obtain a plot which shows amplitudes that seem too large-- with streaks about the middle of the plot(file)
-"BAD" means that I can read the trace header values in HEX, the numbers are correct but that the data values seem too large.
-When I convert from seg2segy I get data value warnings (=0 and < 0), and the data format appears to be in 4-byte integer style.
-I have tried changed "scale" values in seg2segy.c and recompiling but I still get poor results.
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