DALI Release 1.6.0

Using DALI 1.6.0

To upgrade to DALI 1.6.0 from an older version of DALI, follow the installation and usage information in the DALI User Guide.

Note: The internal DALI C++ API used for operator’s implementation, and the C++ API that enables using DALI as a library from native code, is 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 support for lambdas and local functions as callback in parallel external_source operators (#3270, #3269).
  • Added the following tutorials:
    • TensorFlow DALI Dataset input handling (#3212).
    • Parallel external_source operators (#3199).
  • Added DALI preprocessing to the EfficientDet example (#3118).

Fixed Issues

This DALI release includes the following fixes:

  • Fixed a crash that happened in the gaussian_blur operator for inputs where one of the dimensions equals 1 (#3291).
  • Fixed random Python crashes on the process teardown when the external_source operator was used (#3245).
  • Fixed readers.video from hanging on some HEVC samples (#3247).

Breaking Changes

There are no breaking changes in this DALI release.

Deprecated Features

There are no deprecated features in this DALI release.

Known Issues

This DALI release includes the following known issues:

  • 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 frequency that is less than 10-15 frames, the returned frames might be out of sync.

  • The DALI TensorFlow plugin might not be compatible with TensorFlow versions 1.15.0 and later.

    To use DALI with the TensorFlow version that does not have a prebuilt plugin binary that is shipped with DALI, make sure that the compiler that is used to build TensorFlow exists on the system during the plugin installation. (Depending on the particular version, you can use GCC 4.8.4, GCC 4.8.5, or GCC 5.4.)

  • Due to some known issues with meltdown/spectra mitigations and DALI, DALI shows the best performance when running in Docker with escalated privileges, for example:
    • privileged=yes in Extra Settings for AWS data points
    • --privileged or --security-opt seccomp=unconfined for bare Docker