NAME¶
vcd2lxt - Converts VCD files to interlaced or linear LXT files
SYNTAX¶
vcd2lxt [
VCDFILE] [
LXTFILE] [
option]...
DESCRIPTION¶
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.
OPTIONS¶
- -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.
EXAMPLES¶
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.
AUTHORS¶
Anthony Bybell <bybell@rocketmail.com>
SEE ALSO¶
lxt2vcd(1) vcd2lxt2(1) gtkwave(1)