pipeline: support comments in text file (must begin with #)

annotation_pipeline/ingest.cpp

@@ -185,7 +185,8 @@ main (int argc, char *argv[])
 	  pipe[0] = 0;
 	  size_t len = 0;
 	  while ((getline(&line, &len, fp)) != -1) {
-		  strcat(pipe, line);
+		  if (line != nullptr && line[0] != '#')
+			  strcat(pipe, line);
 	  }
 	  fclose(fp);
   } else {

annotation_pipeline/videotestsrc_pipeline.txt

+# video test source pipeline
 
 matroskamux name=mux !
 filesink name=sink location="/tmp/capture.mkv"