ffmpeg parsing

ffmpeg_parse.cc

#include <stdio.h>
#include <iostream>
#include <string>
#include <string.h>

/**
 * This simple argv parser splits a command like:
 * ffmpeg -f libx264 -i  input.avi -acodec libmp3lame -ab 128k -ar 44100 -vcodec 
 * mpeg2video -vf scale=160:128 -b 176k -r 15 -strict -1 -ab  output.mpg
 * 
 * Into its 4 constituent parts.
 *
 * - preamble + input_file_options 
 * - input file name
 * - output_file_options
 * - output file name 
 * 
 * This should work for any ffmpeg command, as this is a requisite of the ffmpeg
 * application.
 *
 * Christopher J. Hanks <cjhanks@cpusage.com>
 */

int 
main(int argc, char* argv[])
{
  std::string input;
  std::string output;
  std::string inp_args;
  std::string out_args;

  bool in_args = true;
  bool in_trigger = false;
  for (int i=1; i<argc; ++i)
    {
      if (in_trigger)
        {
          input = argv[i];
          in_trigger=in_args=false;
        }
      else if (i == argc-1)
        output = argv[i];
      else if (strcmp(argv[i],"-i") == 0)
        in_trigger = true;
      else
        {
          if (in_args)
            inp_args += std::string(argv[i])+" ";
          else  
            out_args += std::string(argv[i])+" ";
        }
    }

  std::cerr<<"Input:  "<<input<<std::endl;
  std::cerr<<"Output: "<<output<<std::endl;
  std::cerr<<"ArgsIn: " << inp_args <<std::endl;
  std::cerr<<"ArgsOut:" << out_args <<std::endl;
  std::cerr<<" ----------------------------"<<std::endl;
  std::cerr<<inp_args << " " << input << " " << out_args << " " <<output << std::endl;
}