Application Migration to DeepStream 6.0.1 from DeepStream 5.X
=============================================================

Major Application Differences with DeepStream 5.X
----------------------------------------------------------
- The `NvBufAudio` structure has been updated. Applications using this structure need to be recompiled.
- When measuring frame latency using DeepStream latency APIs if you observe large frame latency numbers in the order of ``10^12`` or ``1e12``, modify the latency measurement code (call to ``nvds_measure_buffer_latency`` API) to ::

   ...
    guint num_sources_in_batch = nvds_measure_buffer_latency(buf, latency_info);

    if (num_sources_in_batch > 0 && latency_info[0].latency > 1e6) {
     NvDsBatchMeta *batch_meta = gst_buffer_get_nvds_batch_meta (buf);
     batch_meta->batch_user_meta_list = g_list_reverse (batch_meta->batch_user_meta_list);
     num_sources_in_batch = nvds_measure_buffer_latency(buf, latency_info);
    }
   ...

Running DeepStream 5.X compiled Apps in DeepStream 6.0.1
----------------------------------------------------------
To run the old app from DeepStream 5.X in DeepStream 6.0.1, create `symlinks` of the libraries so the old application can find them.::

  mkdir /opt/nvidia/deepstream/deepstream-5.1
  mkdir /opt/nvidia/deepstream/deepstream-5.1/lib
  ln -s /opt/nvidia/deepstream/deepstream-6.0/lib/* /opt/nvidia/deepstream/deepstream-5.1/lib/

Compiling DeepStream 5.1 Apps in DeepStream 6.0.1
---------------------------------------------------
Before compiling DeepStream 5.1 applications in DeepStream 6.0.1, modify the `Makefiles` and set the `NVDS_VERSION` flag to `6.0`.
There are two options to compile DeepStream 5.1 in DeepStream 6.0.1:

1. **Option 1**: Replace existing `sources/apps` from DeepStream-6.0.1 and copy the entire `sources/apps` directory from DeepStream-5.X.
2. **Option 2** : Individual applications in DeepStream SDK have dependency on sources under `apps-common` directory. Ideally, to compile those applications, you must use the same version of `apps-common`. In case you want to use the latest version, you may need to adjust some application function calls because of a change in application function definitions.

.. note::
    By default, OpenCV is deprecated in DeepStream 6.0. However, you can enable OpenCV in plugins such as ``nvinfer`` (``nvdsinfer``) and ``dsexample`` (``gst-dsexample``) by setting `WITH_OPENCV=1` in the Makefile of these components. Please refer component README for more instructions.

Low-level Object Tracker Library Migration from DeepStream 5.1 Apps to DeepStream 6.0.1
---------------------------------------------------------------------------------------
DeepStream 5.1 included three low-level tracker libraries:

* ``libnvds_mot_iou.so``
* ``libnvds_mot_klt.so``
* ``libnvds_nvdcf.so``
|
All of these three low-level tracker libraries are deprecated in DeepStream 6.0.1, and a unified low-level tracker library is introduced, which is ``libnvds_nvmultiobjecttracker.so``.

You'll need to replace the tracker configuration depending on your tracker choice of IOU, NvDCF (w/ perf-oriented setting), NvDCF (w/ accuracy-oriented setting), or DeepSORT. Replace the following: ::

   #ll-lib-file=/opt/nvidia/deepstream/deepstream/lib/libnvds_mot_iou.so
   ll-lib-file=/opt/nvidia/deepstream/deepstream/lib/libnvds_mot_klt.so
   #ll-lib-file=/opt/nvidia/deepstream/deepstream/lib/libnvds_nvdcf.so
   #ll-config-file=tracker_config.yml

with: ::

   ll-lib-file=/opt/nvidia/deepstream/deepstream/lib/libnvds_nvmultiobjecttracker.so
   #ll-config-file=config_tracker_IOU.yml
   ll-config-file=config_tracker_NvDCF_perf.yml
   #ll-config-file=config_tracker_NvDCF_accuracy.yml
   #ll-config-file=config_tracker_DeepSORT.yml