vcd2lxt − Converts VCD files to interlaced or linear LXT files
vcd2lxt [VCDFILE] [LXTFILE] [option]...
Converts VCD files to interlaced or linear LXT files. Noncompressed interlaced files will provide the fastest access, linear files will provide the slowest yet have the greatest compression ratios.
−stats |
Prints out statistics on all nets in VCD file in addition to performing the conversion. |
−clockpack
Apply two−way subtraction algorithm in order to identify nets whose value changes by a constant XOR or whose value increases/decreases by a constant amount per constant unit of time. This option can reduce dumpfile size dramatically as value changes can be represented by an equation rather than explicitly as a triple of time, net, and value.
−chgpack
Emit data to file after being filtered through zlib (gzip).
−linear
Write out LXT in "linear" format with no backpointers. These are re−generated during initialization in gtkwave. Additionally, use libbz2 (bzip2) as the compression filter.
−dictpack <size>
Store value changes greater than or equal to size bits as an index into a dictionary. Experimentation shows that a value of 18 is optimal for most cases.
Note that you should specify dumpfile.vcd directly or use "−" for stdin.
vcd2lxt dumpfile.vcd dumpfile.lxt −clockpack −chgpack −dictpack 18
This turns on clock packing, zlib compression, and enables the dictionary encoding. Note that using no options writes out a normal LXT file.
vcd2lxt dumpfile.vcd dumpfile.lxt −clockpack −linear −dictpack 18
Uses linear mode for even smaller files.
Anthony Bybell <bybell AT nc DOT rr DOT com>