buffer_concatenator
===================

This plugin is designed to concatenate multiple smaller buffers into a larger buffer, effectively improving throughput or compatibility with downstream elements that expect larger, consolidated data chunks.

The buffer_concatenator outputs buffer which contains all buffers one-by-one in the order specified in the ``config.json`` file. If in ``config.json`` specified for buffer ``input_5233`` order ``0`` and for buffer ``input_0`` order ``1`` the plugin output will look like:

::

   [
     [input_5233][input_0]
   ]

Properties
----------

- Concatenate buffers in a specific order
- Copy only first N bytes from input buffer

=================== ========================================================================
Property            Description
=================== ========================================================================
``max-size``        Maximum size (in bytes) for the concatenated buffer
``max-buffers``     Maximum number of buffers to concatenate
``max-time``        Maximum time (in nanoseconds) to hold before pushing
``drop-incomplete`` If ``true``, drops any remaining incomplete buffers on EOS
``passthrough``     If ``true``, bypasses concatenation (for debugging or dynamic switching)
=================== ========================================================================

Installation
~~~~~~~~~~~~

The Yocto SDK must be installed. To compile:

::

   source /opt/poky/4.0.10/environment-setup-cortexa65-poky-linux
   mkdir build && cd build && cmake .. && make

For manual installation copy GStreamer plugin shared library and Edet_Operators library:

``On host:``

::

   scp libbuffer_concatenator.so sima@<IP address of DaVinci board>:/tmp/

``On DaVinci board:``

::

   sudo mv /tmp/libbuffer_concatenator.so /data/your_pipeline/libs/

Usage
-----

Example GStreamer launch string:

::

   GST_PLUGIN_PATH="/data/YOLOV5/lib" \
   GST_DEBUG=2 \
   gst-launch-1.0 --gst-plugin-path="/data/YOLOV5/lib" \
   simaaisrc location="/data/YOLOV5/dump/yuv_sample" node-name="allegrodec" \
   ! process-cvu config="/data/YOLOV5/etc/yolov5_pre_proc.json" source-node-name="allegrodec" buffers-list="allegrodec" \
   ! buffer_concat. \
   simaaisrc location="/data/YOLOV5/dump/mla_out" node-name="mla-yolov5" \
   ! process-cvu config="/data/YOLOV5/etc/yolov5_post_proc.json" source-node-name="mla-yolov5" buffers-list="mla-yolov5" \
   ! buffer_concatenator config="/data/YOLOV5/etc/buffer_concat_config.json" name="buffer_concat" silent=false \
   ! fakesink

Configuration
-------------

Configuration file for this plugin:

::

   {
     "version": 0.1,
     "node_name": "buffer_concat", 
     "memory": {
       "cpu": 0,
       "next_cpu": 0 <================= Memory type used by allocator. 0 means A65 memory will be used
     },
     "system": {
       "out_buf_queue": 1, <=========== Num of output buffers created by the plugin
       "debug": 0,
       "dump_data": 0 <================ Dump the output buffer into file at /tmp
     },
     "buffers": {
       "input": [
         {
           "name": "buffer_1", <======= Name of input buffer
           "size": 36964400, <========= Size of input buffer 
           "order": 0, <=============== Order of buffer in output buffer
           "offset" : 0, <============= Offset from which to start copying 
           "copy_bytes" : 18482200 <=== Size how many bytes should be copied to output buffer 
         },
         {
           "name": "buffer_2",
           "size": 73928800,
           "order": 1,
           "offset" : 36964400, 
           "copy_bytes" : 36964400 
         }
       ],
       "output": {
         "size": 55446600 <============ Output buffer size = Σ(sizes of input buffers specified in this json)
       }
     }
   }

..

   [WARNING] The size of the input buffer in the configuration file should be less or equal to the size of the actual input buffer.