Demo/sgi/video/Vtime.py

   1 #! /usr/bin/env python
   2
   3 # Manipulate the time base of CMIF movies
   4
   5
   6 # Possibilities:
   7 #
   8 # - resample at a fixed rate
   9 # - divide the time codes by a speed factor (to make it go faster/slower)
  10 # - drop frames that are less than n msec apart (to accommodate slow players)
  11
  12
  13 # Usage:
  14 #
  15 # Vtime [-m msec] [-r msec] [-s speed] [infile [outfile]]
  16
  17
  18 # Options:
  19 #
  20 # -m n       : drop frames closer than n msec (default 0)
  21 # -r n       : regenerate input time base n msec apart
  22 # -s speed   : speed change factor after other processing (default 1.0)
  23 # infile     : input file (default film.video)
  24 # outfile    : output file (default out.video)
  25
  26
  27 import sys
  28 sys.path.append('/ufs/guido/src/video')
  29 import VFile
  30 import getopt
  31 import string
  32
  33
  34 # Global options
  35
  36 speed = 1.0
  37 mindelta = 0
  38 regen = None
  39
  40
  41 # Main program -- mostly command line parsing
  42
  43 def main():
  44         global speed, mindelta
  45         opts, args = getopt.getopt(sys.argv[1:], 'm:r:s:')
  46         for opt, arg in opts:
  47                 if opt == '-m':
  48                         mindelta = string.atoi(arg)
  49                 elif opt == '-r':
  50                         regen = string.atoi(arg)
  51                 elif opt == '-s':
  52                         speed = float(eval(arg))
  53         if len(args) < 1:
  54                 args.append('film.video')
  55         if len(args) < 2:
  56                 args.append('out.video')
  57         if len(args) > 2:
  58                 sys.stderr.write('usage: Vtime [options] [infile [outfile]]\n')
  59                 sys.exit(2)
  60         sts = process(args[0], args[1])
  61         sys.exit(sts)
  62
  63
  64 # Copy one file to another
  65
  66 def process(infilename, outfilename):
  67         try:
  68                 vin = VFile.BasicVinFile(infilename)
  69         except IOError, msg:
  70                 sys.stderr.write(infilename + ': I/O error: ' + `msg` + '\n')
  71                 return 1
  72         except VFile.Error, msg:
  73                 sys.stderr.write(msg + '\n')
  74                 return 1
  75         except EOFError:
  76                 sys.stderr.write(infilename + ': EOF in video file\n')
  77                 return 1
  78
  79         try:
  80                 vout = VFile.BasicVoutFile(outfilename)
  81         except IOError, msg:
  82                 sys.stderr.write(outfilename + ': I/O error: ' + `msg` + '\n')
  83                 return 1
  84
  85         vout.setinfo(vin.getinfo())
  86         vout.writeheader()
  87
  88         told = 0
  89         nin = 0
  90         nout = 0
  91         tin = 0
  92         tout = 0
  93
  94         while 1:
  95                 try:
  96                         tin, data, cdata = vin.getnextframe()
  97                 except EOFError:
  98                         break
  99                 nin = nin + 1
 100                 if regen:
 101                         tout = nin * regen
 102                 else:
 103                         tout = tin
 104                 tout = int(tout / speed)
 105                 if tout - told < mindelta:
 106                         continue
 107                 told = tout
 108                 vout.writeframe(tout, data, cdata)
 109                 nout = nout + 1
 110
 111         vout.close()
 112         vin.close()
 113
 114
 115 # Don't forget to call the main program
 116
 117 main()