Made this example a little more interesting.

--HG--
extra : convert_revision : svn%3Afdd8eb12-d10e-0410-9acb-85c331704f74/trunk%403247
This commit is contained in:
Davis King 2009-10-16 14:47:44 +00:00
parent ebe6d3041e
commit 54613abb20
1 changed files with 75 additions and 16 deletions

View File

@ -9,16 +9,17 @@
The output from the program when the -h option is given is:
Usage: dclib_example (-c|-d) --in input_file --out output_file
Usage: dclib_example (-c|-d|-l) --in input_file --out output_file
Options:
-c Indicates that we want to compress a file.
-d Indicates that we want to decompress a file.
-h Display this help message.
--in <arg> This option takes one argument which specifies the
name of the file we want to compress/decompress.
--out <arg> This option takes one argument which specifies the
name of the output file.
-c Indicates that we want to compress a file.
-d Indicates that we want to decompress a file.
-h Display this help message.
--in <arg> This option takes one argument which specifies the name of the
file we want to compress/decompress.
-l <arg> Set the compression level [1-3], 3 is max compression, default
is 2.
--out <arg> This option takes one argument which specifies the name of the
output file.
*/
@ -30,9 +31,10 @@
#include <fstream>
#include <string>
// I am making a typedef for the version of compress_stream I want to use.
// I have selected kernel_1ec.
typedef dlib::compress_stream::kernel_1ec cs;
// I am making a typedef for the versions of compress_stream I want to use.
typedef dlib::compress_stream::kernel_1da cs1;
typedef dlib::compress_stream::kernel_1ea cs2;
typedef dlib::compress_stream::kernel_1ec cs3;
// Here I am making another typedef, this time for the version of
// cmd_line_parser I want to use. This version gives me a
@ -51,7 +53,6 @@ int main(int argc, char** argv)
try
{
clp parser;
cs compressor;
// first I will define the command line options I want.
// Add a -c option and tell the parser what the option is for.
@ -62,6 +63,7 @@ int main(int argc, char** argv)
// add a --out option that takes 1 argument
parser.add_option("out","This option takes one argument which specifies the name of the output file.",1);
parser.add_option("h","Display this help message.");
parser.add_option("l","Set the compression level [1-3], 3 is max compression, default is 2.",1);
// now I will parse the command line
@ -80,13 +82,22 @@ int main(int argc, char** argv)
// Here I'm checking that the user didn't pick both the c and d options at the
// same time.
parser.check_incompatible_options("c", "d");
// You can't set the compression level during decompression. The level is read from the compressed file.
parser.check_incompatible_options("l", "d");
// Here I'm checking that the argument to the l option is an integer in the range 1 to 3.
// That is, it should be convertible to an int by dlib::string_cast<int>() and be either
// 1, 2, or 3. Note that if you wanted to allow floating point values in the range 1 to
// 3 then you could give a range 1.0 to 3.0 or explicitly supply a type of float or double
// to the template argument of the check_option_arg_range() function.
parser.check_option_arg_range("l", 1, 3);
// check if the -h option was given on the command line
if (parser.option("h"))
{
// display all the command line options
cout << "Usage: dclib_example (-c|-d) --in input_file --out output_file\n";
cout << "Usage: dclib_example (-c|-d|-l) --in input_file --out output_file\n";
// This function prints out a nicely formatted list of
// all the options the parser has
parser.print_options(cout);
@ -102,6 +113,14 @@ int main(int argc, char** argv)
const clp::option_type& option_in = parser.option("in");
const clp::option_type& option_out = parser.option("out");
// Figure out what the compression level should be. The default is 2.
int compression_level = 2;
// If the user supplied the -l option then use whatever value they gave for the level.
if (parser.option("l"))
compression_level = string_cast<int>(parser.option("l").argument());
// make sure one of the c or d options was given
if (!option_c && !option_d)
{
@ -164,11 +183,51 @@ int main(int argc, char** argv)
// now perform the actual compression or decompression.
if (option_c)
{
compressor.compress(fin,fout);
// save the compression level to the output file
serialize(compression_level, fout);
switch (compression_level)
{
case 1:
{
cs1 compressor;
compressor.compress(fin,fout);
}break;
case 2:
{
cs2 compressor;
compressor.compress(fin,fout);
}break;
case 3:
{
cs3 compressor;
compressor.compress(fin,fout);
}break;
}
}
else
{
compressor.decompress(fin,fout);
// obtain the compression level from the input file
deserialize(compression_level, fin);
switch (compression_level)
{
case 1:
{
cs1 compressor;
compressor.decompress(fin,fout);
}break;
case 2:
{
cs2 compressor;
compressor.decompress(fin,fout);
}break;
case 3:
{
cs3 compressor;
compressor.decompress(fin,fout);
}break;
}
}