DALI Release 0.9.1 Beta

The DALI 0.9.1 is a beta release. Hence, for all the features, the functionality and performance will likely be limited.

Using DALI 0.9.1 Beta

The DALI 0.9.1 can be used with the 19.05 NVIDIA GPU Cloud (NGC) optimized container for MXNet, PyTorch, and TensorFlow. Also, the 19.05 container will be shipped with DALI 0.9.1.

To upgrade to DALI 0.9.1 beta from an older version of DALI, follow the installation instructions in the DALI Quick Start Guide.

Refer to the DALI Developer Guide for usage details.

Note: The internal DALI C++ API used for operators implementation, and the C++ API that enables using DALI as a library from native code, are not yet officially supported. Hence these APIs may change in the next release without advance notice.

Key Features and Enhancements

This DALI release includes the following key features and enhancements.

  • Added Optical Flow example.
  • Added full support for .pnm (.ppm/.pgm/.pbm) (in case of nvJPEG, fallback to CPU is done).
  • Added the ability to do the lazy initialization of DALI. It is now possible to separate touching the data during the actual run, and at the time of all the necessary allocations during the build of the pipeline.
  • Reduced the resize operator scratch buffer size by processing the data in mini batches.
  • Added the ability to set the DALI CUDA streams priority.
  • Fixed the sync issue in the DALI Python iterators.
  • Fixed the initialization of CUDA context on the default device during pipeline creation.

Breaking API Changes

  • Internal Python pipeline API has changed. If any function _* was used, then that function should be updated to reflect the new semantic.

Deprecated Features

  • None.

Known Issues

  • The new video reader operator requires NVIDIA VIDEO CODEC SDK support in the platform. Prior to 19.01, the NVIDIA GPU Cloud (NGC) optimized containers lack this functionality in the default configuration. To enable the functionality, run the container with the "video" capability enabled, as shown below:
    -e "NVIDIA_DRIVER_CAPABILITIES=compute,utility,video"
  • The video loader operator requires that the key frames occur at a minimum every 10 to 15 frames of the video stream. If the key frames occur at a lesser frequency, then the returned frames may be out of sync.