> This page is for version 9.2 (default). > For other versions, use one of these documentation indexes: > - 9.2 (default): https://docs.nvidia.com/deepstream/9.2/llms.txt > - Archives: https://docs.nvidia.com/deepstream/archives/llms.txt > For clean Markdown of any page, append .md to the page URL. > For a complete documentation index, see https://docs.nvidia.com/deepstream/llms.txt. > For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.nvidia.com/deepstream/_mcp/server. # Gst-nvunixfd The Gst-nvunixfd plugin performs the hardware video buffers sharing between different processes and pipelines via IPC (inter-process communication). Gst-nvunixfd provides the Gst-nvunixfdsink and Gst-nvunixfdsrc for sending and receiving the hardware video buffers between pipelines to avoid unnecessary memory copy. Gst-nvunixfdsink acts as a server, the NvBufSurfaceMapParams which contains the video buffer information and the IPC sharable FD(File Descriptor) of the video buffer are sent to the Gst-nvunixfdsrc. Gst-nvunixfdsrc then creates a new NvBufSurface with the received data. On Jetson, FD is the bufferDesc in the NvBufSurface structure. On DGPU, FD is a cudaIpcMemHandle_t handle derived from the CUDA memory. The Gst-nvunixfdsink pipeline can send hardware video buffers to multiple Gst-nvunixfdsrc pipelines, the Gst-nvunixfdsrc pipeline can receive hardware video buffers from multiple Gst-nvunixfdsink pipelines. All the pipelines should work in the same device and the same system. The batched NvBufSurface is not supported. ## Gst-nvunixfdsink Gst-nvunixfdsink is a Unix file descriptor sink derived from OSS unixfdsink element, which is used on server side. ![Gst-nvunixfd](/deepstream/_fern-img/d0c87672ea93d4077a4434b5a805ed9cc1096629e3892f46f3919d2701a18add.webp) ## Inputs and Outputs * Inputs * Gst no-batched buffer * Control parameters * gpu-id: selects the GPU ID * buffer-copy: copy buffer for every client * buffer-timestamp-copy: copy timestamp of the received Gst buffers * compute-hw: Compute HW for copy operation * meta-serialization-lib: Set meta serialization library name to be used * socket-type: The type of underlying socket * socket-path: The path to the control socket used to control the shared memory * Output * After client connects, server passes the NvBufSurface handle, timestamp and other data to client through IPC. ## Features The following table summarizes the features of the Gst-nvunixfdsink plugin. **Gst-nvunixfdsink plugin features** | Feature | Description | Release | | ----------------------- | ---------------------------------------------------------------------------------------------------- | ------- | | Configure GPU selection | Sets the GPU ID to be used for optical flow visualization operations (valid only for dGPU platforms) | DS 8.0 | | buffer copy | copy buffer for every client | DS 8.0 | | buffer timestamp copy | copy timestamp of received buffer | DS 8.0 | | compute HW | Compute HW for copy operation | DS 8.0 | | meta serialization lib | Set meta serialization library name to be used | DS 8.0 | | socket type | The type of underlying socket | DS 8.0 | | socket path | The path to the control socket used to control the shared memory | DS 8.0 | ## Gst-nvunixfdsrc Gst-nvunixfdsrc is a Unix file descriptor source derived from OSS unixfdsrc element, which is used on client side. ![Gst-nvunixfd](/deepstream/_fern-img/313eeda1ab9ef975d30325ac7f21042afe980b25eb16bb3de6f3fdf6c5097bec.webp) ## Inputs and Outputs * Inputs * The NvBufSurface handle, timestamp and other data received from server. * Control parameters * gpu-id: selects the GPU ID * buffer-copy: copy buffer for every client * buffer-timestamp-copy: copy timestamp of received buffer * compute-hw: Compute HW for copy operation * meta-deserialization-lib: Set meta deserialization library name to be used * socket-type: The type of underlying socket * socket-path: The path to the control socket used to control the shared memory * connection-attempts: Max number of attempts for connection (-1 = unlimited) * connection-interval: Connection interval between connection attempts in micro seconds * Output * Gst no-batched buffer ## Features The following table summarizes the features of the Gst-nvunixfdsrc plugin. **Gst-nvunixfdsrc plugin features** | Feature | Description | Release | | ------------------------ | ---------------------------------------------------------------------------------------------------- | ------- | | Configure GPU selection | Sets the GPU ID to be used for optical flow visualization operations (valid only for dGPU platforms) | DS 8.0 | | buffer copy | copy buffer for every client | DS 8.0 | | buffer timestamp copy | copy timestamp of received buffer | DS 8.0 | | compute HW | Compute HW for copy operation | DS 8.0 | | meta deserialization lib | Set meta deserialization library name to be used | DS 8.0 | | socket type | The type of underlying socket | DS 8.0 | | socket path | The path to the control socket used to control the shared memory | DS 8.0 | | connection attempts | Max number of attempts for connection | DS 8.0 | | connection interval | connection interval | DS 8.0 | ## Gst Properties The following table describes the Gst properties of the Gst-nvunixfdsrc plugin. **Gst-nvunixfdsrc plugin gst properties** | Property | Meaning | Type and Range | Example Notes | | ---------------------- | ----------------------------------------------------------------------------------------------------- | --------------------------- | ---------------------------------------------------------------------------------- | | gpu-id | Device ID of the GPU to be used(dGPU only) | Integer,0 to 4,294,967,295 | gpu-id=0 | | buffer-copy | Buffer copy | Boolean. Default: false | buffer-copy=0 | | buffer-timestamp-copy | Buffer copy | Boolean. Default: false | buffer-copy=0 | | compute-hw | Type of computing hardware: 0: Default (GPU for gDPU, CPU for Jetson) 1: VLC( only for Jetson) 2: GPU | enum GstComputeHW | compute-hw=0 Default value is 0. | | buffer-timestamp-copy | Buffer copy | Boolean. Default: false | buffer-copy=0 | | meta-serialization-lib | Meta serialization library name | String | ./lib/serialization.so | | socket-type | socket type | enum GUnixSocketAddressType | socket-type=G_UNIX_SOCKET_ADDRESS_PATH,Default value is G_UNIX_SOCKET_ADDRESS_PATH | | socket-path | Path to the control socket | String | socket-path=/tmp/test1 | | connection-attempts | Max number of attempts for connection (-1 = unlimited) | int | connection-attempts=3,Default: -1 | | connection-interval | Path to the control socket | int | connection-interval=3000000,Default: 1000000 |