Unable to play a specific Widevine stream in dash.js

nagai_kazuki · May 29, 2025, 5:43am

Before you continue

Ask yourself if this is a bug related to Kepler. Before submitting a bug report, please review our troubleshooting documentation at https://developer.amazon.com/docs/kepler-tv/kepler_overview.html.

Please select the nature of the issue.

Bug
Improvement / Suggestion
Issue with documentation

Reason : Since playback is possible in the browser’s dash.js demo, this is a bug specific to Kepler.

Helpful commands to retrieve information

System Information

Checking installation status at /Users/s11081/.kepler/kntools/sdk/0.19.6
A different location can be specified via environment variable KEPLER_SDK_PATH.

✔ System: macOS 15.5
  Architecture: aarch64
✔ Rosetta not enabled
✔ username and token found in knrc file
✔ git found in the path
✔ curl found in the path
✔ Node.js binary compiled for aarch64
✔ VSCode found in the path
✔ XCode Command Line Tools is up to date
✔ /Users/s11081/.kepler/kntools/sdk/0.19.6 exists; /Users/s11081/.kepler/kntools exists
✔ licenses and legal notices found in /Users/s11081/.kepler/kntools/sdk/0.19.6
✔ Installed system packages:
  autossh 1.4g
  binutils 2.44
  coreutils 9.7
  gawk 5.3.1
  findutils 4.10.0
  glib 2.84.1
  gnutls 3.8.9
  grep 3.12
  jpeg turbo 3.1.0
  jq 1.7.1
  libepoxy 1.5.10
  libpng 1.6.48
  libslirp 4.9.0
  libssh 0.11.1
  libusb 1.0.28
  lzo 2.10
  lz4 1.10.0
  nettle 3.10.1
  openssh 9.9p2
  pixman 0.46.0
  sdl2 2.32.6
  snappy 1.2.1
  tmux 3.5a
  unzip 6.0_8
  vde 2.3.3
  xz 5.8.1
  gnu-sed 4.9
  watchman 2025.04.28.00
  zstd 1.5.7
✔ pyenv version 2.5.7 installed
✔ python version 3.12.6 installed
✔ pip version 24.2 installed
✔ pyenv virtualenv version 1.2.4 installed
✔ virtualenv 'kepler-0.19.6' created
✔ Installed Python packages: 
  conan 2.0.17
  docopt 0.6.2
  flatbuffers 23.5.26
  langcodes 3.3.0
  psutil 7.0.0
  PyYAML 6.0.1
  tomli 2.0.1
  wheel 0.41.3
  zstandard 0.22.0
✔ debugger server found
✔ simulator exists at /Users/s11081/.kepler/kntools/sdk/0.19.6/simulator/tools/runsimulator
✔ vda version 2.1.0 installed
✔ Vega Packaging Tools vpt binary exists in /Users/s11081/.kepler/kntools/sdk/0.19.6/vegapackagingtool/bin/vpt
✔ Hermes Compiler binary exists at /Users/s11081/.kepler/kntools/sdk/0.19.6/hermes/072/bin/hermesc
✔ kvdi skipped since simulator is installed
✔ kvd-tv skipped since simulator is installed
✔ Heaptrack Tools binaries exist in /Users/s11081/.kepler/kntools/sdk/0.19.6/heaptrack_prebuilts
✔ Kepler Debugging Tools binaries exist in /Users/s11081/.kepler/kntools/sdk/0.19.6/kepler_debugging_tools/tools/scripts
✔ Kepler Manifest Module Remapper amzn-kepler-manifest-module-remapper binary exists in /Users/s11081/.kepler/kntools/sdk/0.19.6/kepler_manifest_module_remapper/bin/amzn-kepler-manifest-module-remapper
✔ CPU profiling tool for performance analysis binaries exist in /Users/s11081/.kepler/kntools/sdk/0.19.6/simpleperf_prebuilts
✔ Corretto JDK version 11.0.20.8.1 installed
✔ Kepler Performance CLI binaries exist in /Users/s11081/.kepler/kntools/sdk/0.19.6/kepler_perf_cli
✔ Kepler Studio extensions installed in VSCode
✔ environment setup file exists at /Users/s11081/.kepler/kntools/sdk/0.19.6/environment-setup-sdk.sh and has correct contents
✔ /Users/s11081/.kepler/kntools/sdk/0.19.6/environment-setup-sdk.sh is sourced from /Users/s11081/.zprofile
⚠ Telemetry Service exists at /Users/s11081/.kepler/kntools/sdk/0.19.6/kepler-telemetry/telemetry. Configuration file exists at /Users/s11081/.kepler/kntools/sdk/0.19.6/kepler-telemetry/config.json. Collection of anonymous usage data is disabled


Kepler CLI prerequisites are all correctly installed.

Bug Description

1. Summary

We are unable to play our MPEG-DASH Widevine content on dash.js.

While it plays properly in the dash.js demo, it cannot be played on Kepler devices using Amazon Reference.

App Name: ABEMA
App Link on Amazon Appstore ABEMA - App on Amazon Appstore

Bug Severity
Select one that applies

Impacts operation of app
Blocks current development
Improvement suggestion
Other

It will block the release of the app.

2. Steps to Reproduce

We will provide our MPD and license server URL via private email, so you can reproduce the issue by playing it using https://developer.amazon.com/docs/kepler-tv/media-player-dash-player.html.

3. Observed Behavior

Playback does not start.

4. Expected Behavior

Playback starts correctly.

4.a Possible Root Cause & Temporary Workaround

N/A

5. Environment

SDK Version: 0.19
App State: Foreground
React Native Version: 0.72.0
React Version: 18.2.0
Platform: TV
Device Model(s): [Leave blank]

If it is a player issue, please share the following details in addition:

Player SDK: dash.js
Player SDK Version: Link
- Audio Codecs: [mp4a.40.2]
- Video Codecs: [avc1.4D401f]
- Manifest Types: dash

6. Example Code Snippet / Screenshots / Screengrabs

https://developer.amazon.com/docs/kepler-tv/media-player-dash-player.html

Playback Issues

Q: Would you like to be contacted to share your latest VPKG compiled with latest SDK:

[N] [Share privately with your Amazon contact]

Q: VPN or Login needed to verify functionality in VPKG?

[N] [Share privately with your Amazon contact]

Q: If applicable, please provide your media/content url

[Y] [Share privately with your Amazon contact]

I would like to provide the stream, but how can I share it exclusively with Amazon?

Also, will the provided stream remain confidential and not be disclosed to parties other than Amazon?

Q: Are there any special headers required to reproduce the issue you are facing?

[N]

If you are able to test on a device or simulator

Device: OS 1.1(201010434450)

Siva_Prakash · May 30, 2025, 6:29am

Hi @nagai_kazuki,

Thanks for reporting this issue. Please provide media/content URL privately to your Amazon contact (who can ensure that it remains confidential within Amazon).

Regards,
Siva

Shun_Iguchi · May 30, 2025, 6:57am

@nagai_kazuki Please provide the information in private. Thank you

nagai_kazuki · June 25, 2025, 4:34am

@Siva_Prakash @Shun_Iguchi

Any updates?

Since our Widevine streams cannot be played, there’s no point in proceeding with other developments, which is having a serious impact on the provision of our app. To raise our commitment priority to Kepler, we request that you prioritize addressing this issue as much as possible.

The streams in question can be played using the browser’s dash.js, so there’s a high possibility that the problem lies on the Kepler side.

Siva_Prakash · June 25, 2025, 5:25am