Convert /third_party/ffmpeg to gyp and a python build script.

third_party/ffmpeg/generate_libs.py

Index: third_party/ffmpeg/generate_libs.py
diff --git a/third_party/ffmpeg/generate_libs.py b/third_party/ffmpeg/generate_libs.py
new file mode 100644
index 0000000000000000000000000000000000000000..9a8faeb51b1b517e7ef9c4e149b7a83e78d0605c
--- /dev/null
+++ b/third_party/ffmpeg/generate_libs.py
@@ -0,0 +1,36 @@
+#!/usr/bin/python
+# Generates MSVC import libraries from .def files.  Assumes MSVC environment
+# has been loaded.
+
+import optparse
+import os
+import subprocess
+
+def main():
+  parser = optparse.OptionParser(usage='usage: %prog [options] input')
+  parser.add_option('-o',
+                    '--output',
+                    dest='output',
+                    default=None,
+                    help=('output location'))
+  (options, args) = parser.parse_args()
+
+  if options.output == None:
+    parser.error('Output location not specified')
+  if len(args) == 0:
+    parser.error('No inputs specified')
+
+  # Make sure output directory exists.
+  if not os.path.exists(options.output):
+    os.makedirs(options.output)
+
+  # Run lib.exe on each input def file.
+  for input_path in args:
+    input_name = os.path.basename(input_path)
+    input_root = os.path.splitext(input_name)[0]
+    output_path = os.path.join(options.output, input_root + '.lib')
+    subprocess.call(['lib', '/nologo', '/machine:X86', '/def:' + input_path,
+                     '/out:' + output_path])
+
+if __name__ == '__main__':
+  main()