Integer divide by zero

[Gr3yD0g]

sirius@lambda:~/Desktop/stegdetect-master$ valgrind ./stegdetect -tF ../crashes/id:000004,sig:08,src:000000,op:flip4,pos:27
==91481== Memcheck, a memory error detector
==91481== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al.
==91481== Using Valgrind-3.11.0 and LibVEX; rerun with -h for copyright info
==91481== Command: ./stegdetect -tF ../crashes/id:000004,sig:08,src:000000,op:flip4,pos:27
==91481==
==91481==
==91481== Process terminating with default action of signal 8 (SIGFPE): dumping core
==91481== Integer divide by zero at address 0x802DDAE53
==91481== at 0x4166F8: forward_DCT (in /home/sirius/Desktop/stegdetect-master/stegdetect)
==91481== by 0x41193D: compress_data (in /home/sirius/Desktop/stegdetect-master/stegdetect)
==91481== by 0x4108A6: process_data_simple_main (in /home/sirius/Desktop/stegdetect-master/stegdetect)
==91481== by 0x40D603: jpeg_write_scanlines (in /home/sirius/Desktop/stegdetect-master/stegdetect)
==91481== by 0x40AD47: f5_compress (f5.c:136)
==91481== by 0x40BE79: detect_f5 (f5.c:505)
==91481== by 0x4067C7: detect (stegdetect.c:1213)
==91481== by 0x402087: main (stegdetect.c:1568)
==91481==
==91481== HEAP SUMMARY:
==91481== in use at exit: 165,584 bytes in 83 blocks
==91481== total heap usage: 87 allocs, 4 frees, 171,832 bytes allocated
==91481==
==91481== LEAK SUMMARY:
==91481== definitely lost: 108,032 bytes in 2 blocks
==91481== indirectly lost: 0 bytes in 0 blocks
==91481== possibly lost: 0 bytes in 0 blocks
==91481== still reachable: 57,552 bytes in 81 blocks
==91481== suppressed: 0 bytes in 0 blocks
==91481== Rerun with --leak-check=full to see details of leaked memory
==91481==
==91481== For counts of detected and suppressed errors, rerun with: -v
==91481== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)
Floating point exception

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