L4T Multimedia API Reference

31.1 Release

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Multimedia API Sample Applications

This toolkit includes NVIDIA Multimedia API sample applications that you can use as building blocks to construct applications for your product use case, such as:

  • DVR/NVR
  • IVA camera surveillance
  • Drones
  • Robotics

The sample applications demonstrate how to use the Multimedia API and other libraries, such as:

  • NVIDIA® TensorRT
  • NVIDIA® CUDA®
  • cuDNN
  • OpenCV
  • Libargus
  • NVDC-DRM

The following table describes the samples.

Directory Location Relative to ll_samples/samples Description
02_video_dec_cuda Decodes H.264/H.265 video from a local file and then shares the YUV buffer with CUDA to draw a black box in the left corner.
03_video_cuda_enc Use CUDA to draw a black box in the YUV buffer and then feeds it to video encoder to generate an H.264/H.265 video file.
04_video_dec_trt Uses simple TensorRT calls to save the bounding box info to a file.
05_jpeg_encode Uses libjpeg-8b APIs to encode JPEG images from software-allocated buffers.
06_jpeg_decode Uses libjpeg-8b APIs to decode a JPEG image from software-allocated buffers.
07_video_convert Uses V4L2 APIs to do video format conversion and video scaling.
08_video_dec_drm Uses the NVIDIA® Tegra® Direct Rendering Manager (DRM) to render video stream or UI.
09_camera_jpeg_capture Simultaneously uses Libargus API to preview camera stream and libjpeg-8b APIs to encode JPEG images.
10_camera_recording Gets the real-time camera stream from the Libargus API and feeds it into the video encoder to generate H.264/H.265 video files.
12_camera_v4l2_cuda Captures images from a V4L2 camera and shares the stream with CUDA engines to draw a black box in the upper left corner.
13_multi_camera Captures multiple cameras and composites them to one frame.
Backend Performs intelligent video analytics on four concurrent video streams going through a decoding process using the on chip decoders, video scaling using on chip scalar, and GPU compute.
Frontend Performs independent processing on four different resolutions of video capture coming directly from camera.
v4l2cuda (capture-cuda) Uses V4L2 image capturing with CUDA format conversion.

There is one tool that the samples can use.

Tool Name Description Directory Location
CAFFE to TensorRT Model Tool Standalone tool that converts a CAFFE network to a TensorRT-compatible model and saves the model stream into local file for subsequent usage. tools/ConvertCaffeToTrtModel

L4T Software Stack

The following diagram illustrates the L4T software stack. Of the Multimedia box (center, bottom), the Multimedia API provides the following components:

  • libargus for imaging applications
  • NVDC-DRM for non-X11 display system
  • V4L2 API for encoding, decoding, scaling, and other media functions
  • NVOSD for drawing text and box on the screen

With these components, you can access the other libraries, such as TensorRT and cuDNN.