add capnp and ffmpeg (#4)

ffmpeg/ffmpeg/__init__.py

@@ -0,0 +1,20 @@
+import os
+import sys
+
+DIR = os.path.join(os.path.dirname(__file__), "install")
+BIN_DIR = os.path.join(DIR, "bin")
+LIB_DIR = os.path.join(DIR, "lib")
+INCLUDE_DIR = os.path.join(DIR, "include")
+
+
+def _run(name):
+  binary = os.path.join(BIN_DIR, name)
+  os.execvp(binary, [binary] + sys.argv[1:])
+
+
+def _run_ffmpeg():
+  _run("ffmpeg")
+
+
+def _run_ffprobe():
+  _run("ffprobe")