The video decoder performance tests are a set of tests used to measure the performance of various video decoder implementations. These tests run directly on top of the video decoder implementation, and don't require the full Chrome browser stack. They are build on top of the GoogleTest framework.
Note: The video decoder performance tests are in the progress of being added to the Tast framework. This section will be updated once this is done.
To run the video decoder performance tests manually the video_decode_accelerator_perf_tests target needs to be built and deployed to the device being tested. Running the video decoder performance tests can be done by executing:
./video_decode_accelerator_perf_tests [<video path>] [<video metadata path>]
Video Metadata: These videos also have an accompanying metadata .json file that needs to be deployed alongside the test video. They can also be found in the media/test/data folder (e.g. test-25fps.h264.json). If no metadata file is specified <video path>.json will be used. The video metadata file contains info about the video such as its codec profile, dimensions and number of frames.
Note: Various CPU scaling and thermal throttling mechanisms might be active on the device (e.g. scaling_governor, intel_pstate). As these can influence test results it's advised to disable them.
Currently uncapped decoder performance is measured by playing the specified test video from start to finish. Various performance metrics (e.g. the number of frames decoded per second) are collected, and written to a file called perf_metrics/<test_name>.txt. Individual frame decode times can be found in perf_metrics/<test_name>.frame_times.txt.
Note: A capped performance test is in the process of being added. This test will simulate a more realistic real-time decoding environment.
Multiple command line arguments can be given to the command:
-v enable verbose mode, e.g. -v=2. --vmodule enable verbose mode for the specified module, e.g. --vmodule=*media/gpu*=2. --output_folder overwrite the output folder used to store performance metrics, if not specified results will be stored in the current working directory. --use_vd use the new VD-based video decoders, instead of the default VDA-based video decoders. --gtest_help display the gtest help and exit. --help display this help and exit.
See the video decoder performance tests source code.