private InputStream getInputStream(
      String urlStr, Format outputFormat, ContentDescriptor outputContentDescriptor)
      throws Exception {
    final ProcessorModel processorModel =
        new ProcessorModel(
            new MediaLocator(urlStr),
            outputFormat == null ? null : new Format[] {outputFormat},
            outputContentDescriptor);

    final Processor processor = Manager.createRealizedProcessor(processorModel);

    final DataSource ds = processor.getDataOutput();

    final DataSink[] streamDataSinkHolder = new DataSink[] {null};
    // connect the data output of the processor to a StreamDataSink, which
    // will make the data available to PipedInputStream, which we return.
    final PipedInputStream in =
        new PipedInputStream() {
          // override close to clean up everything when the media has been
          // served.
          @Override
          public void close() throws IOException {
            super.close();
            logger.fine("Closed input stream");
            logger.fine("Stopping processor");
            processor.stop();
            logger.fine("Closing processor");
            processor.close();
            logger.fine("Deallocating processor");
            processor.deallocate();
            if (streamDataSinkHolder[0] != null) {
              logger.fine("Closing StreamDataSink");
              streamDataSinkHolder[0].close();
            }
          }
        };
    final PipedOutputStream out = new PipedOutputStream(in);
    final DataSink streamDataSink = new StreamDataSink(out);
    streamDataSinkHolder[0] = streamDataSink;

    streamDataSink.setSource(ds);
    streamDataSink.open();
    streamDataSink.start();

    logger.info("Starting processor");
    processor.start();

    // TODO: if there is an error, make sure we clean up.
    // for example, if the client breaks the connection.
    // we need a controller listener to listen for errors.

    return in;
  }
  @Override
  public Response serve(String uri, String method, Properties header, Properties parms) {
    if (!uri.equals("/mediaserver")) {
      return super.serve(uri, method, header, parms); // this way we can
      // also serve up
      // normal files and
      // content
    }

    logger.fine(method + " '" + uri + "' ");

    Enumeration<?> e = header.propertyNames();
    while (e.hasMoreElements()) {
      String value = (String) e.nextElement();
      logger.fine("  HDR: '" + value + "' = '" + header.getProperty(value) + "'");
    }
    e = parms.propertyNames();
    while (e.hasMoreElements()) {
      String value = (String) e.nextElement();
      logger.fine("  PRM: '" + value + "' = '" + parms.getProperty(value) + "'");
    }

    // TODO: check the actual path...

    final String mediaPath = parms.getProperty("media");
    final String outputFormatStr = parms.getProperty("format");
    final String mimeType = parms.getProperty("mime");
    logger.info("requested media: " + mediaPath);
    logger.info("requested mime type: " + mimeType);
    if (mediaPath == null)
      return new Response(HTTP_FORBIDDEN, "text/plain", "mediaPath parameter not specified");
    if (mimeType == null)
      return new Response(HTTP_FORBIDDEN, "text/plain", "mimeType parameter not specified");

    // TODO: if we aren't performing any transcoding, just serve the file up
    // directly.
    // TODO: capture sources need to be treated as singletons, with some
    // kind of broadcasting/cloning to ensure
    // that multiple connections can be made.

    final String serverSideUrlStr = mediaPath; // URLUtils.createUrlStr(new
    // File(mediaPath)); // TODO:
    // enforce that we can't just
    // serve up anything anywhere
    final ContentDescriptor outputContentDescriptor =
        new FileTypeDescriptor(ContentDescriptor.mimeTypeToPackageName(mimeType));

    final Format outputFormat;
    if (outputFormatStr == null) {
      outputFormat = null;
    } else {
      try {
        outputFormat = FormatArgUtils.parse(outputFormatStr);
      } catch (ParseException e1) {
        logger.log(Level.WARNING, "" + e1, e1);
        return new Response(HTTP_FORBIDDEN, "text/plain", "" + e1);
      }
    }

    logger.info("serverSideUrlStr: " + serverSideUrlStr);
    logger.info("outputContentDescriptor: " + outputContentDescriptor);
    logger.info("outputFormat: " + outputFormat);

    final InputStream is;
    try {
      is = getInputStream(serverSideUrlStr, outputFormat, outputContentDescriptor);
    } catch (Exception e1) {
      return new Response(HTTP_FORBIDDEN, "text/plain", "" + e1);
    }

    final String responseMimeType;
    // workaround for the problem that the multipart/x-mixed-replace
    // boundary is not stored anywhere.
    // this assumes that if we are serving multipart/x-mixed-replace data,
    // that MultipartMixedReplaceMux is being used.
    if (mimeType.equals("multipart/x-mixed-replace"))
      responseMimeType = mimeType + ";boundary=" + MultipartMixedReplaceMux.BOUNDARY;
    else responseMimeType = mimeType;
    logger.info("Response mime type: " + responseMimeType);
    return new Response(HTTP_OK, responseMimeType, is);
  }