SCTE-35 being read as x-emsg rather than x-scte35

Version

Media3 1.5.0

More version details

No response

Devices that reproduce the issue

• Pixel 8 Pro API 35 Emulator

Devices that do not reproduce the issue

No response

Reproducible in the demo app?

Not tested

Reproduction steps

1. Add a new renderer and set it to your player

val renderersFactory: RenderersFactory = object : DefaultRenderersFactory(context) {
            override fun buildMetadataRenderers(context: Context, output: MetadataOutput, outputLooper: Looper, extensionRendererMode: Int, out: ArrayList<Renderer>) {
                val metadataRenderer = MetadataRenderer(
                        output,
                        outputLooper,
                        CustomMetadataDecoderFactory()
                )

                out.add(metadataRenderer)
            }
        }

2. Create the CustomMetadataDecoderFactory()

@UnstableApi
class CustomMetadataDecoderFactory : MetadataDecoderFactory {
    override fun supportsFormat(format: Format): Boolean {
        Log.i("CustomMetadataDecoder", "Format: ${format.sampleMimeType}")

        // Ensure support for the MIME type used by SCTE-35 metadata
        return format.sampleMimeType == "application/x-scte35" || format.sampleMimeType == "application/x-emsg"
    }

    override fun createDecoder(format: Format): MetadataDecoder {
        Log.i("CustomMetadataDecoder", "Decoder Metadata: ${format.metadata}")

        if(format.sampleMimeType == "application/x-emsg") {
            Log.i("CustomMetadataDecoder", "Decoding using EventMessageDecoder")
            return EventMessageDecoder()
        }

        Log.i("CustomMetadataDecoder", "Decoding using SpliceInfoDecoder")
        return SpliceInfoDecoder()
    }
}

3. Play the DASH file

DASH File Period Sample:

<Period id='1732293437' start="PT0S" >
      <EventStream schemeIdUri="urn:scte:scte35:2014:xml+bin" timescale="1000">
        <Event id="0" presentationTime="1732294630134">
          <Signal xmlns="http://www.scte.org/schemas/35/2016">
            <Binary>/DBOAAAAAAAAAP/wBQb+gnX6iAA4AjZDVUVJAYAIhH/DAAD3NtEOIE0xU2F1SjZkeUtiQnl2WUY1b0hZSkhINWtKNG1XT1JvNAAAAABYZSZy</Binary>
          </Signal>
        </Event>
        <Event id="0" presentationTime="1732294636140">
          <Signal xmlns="http://www.scte.org/schemas/35/2016">
            <Binary>/DBOAAAAAAAAAP/wBQb+gnX6iAA4AjZDVUVJAYAIhH/DAAD3NtEOIE0xU2F1SjZkeUtiQnl2WUY1b0hZSkhINWtKNG1XT1JvNAAAAABYZSZy</Binary>
          </Signal>
        </Event>
        <Event id="0" presentationTime="1732294642146">
          <Signal xmlns="http://www.scte.org/schemas/35/2016">
            <Binary>/DBOAAAAAAAAAP/wBQb+gnX6iAA4AjZDVUVJAYAIhH/DAAD3NtEOIE0xU2F1SjZkeUtiQnl2WUY1b0hZSkhINWtKNG1XT1JvNAAAAABYZSZy</Binary>
          </Signal>
        </Event>
        ...

Expected result

SCTE-35 metadata will be read as application/x-scte35, and data would be available under onMetadata callback with the ID, Duration (optional), and Value.

Actual result

SCTE-35 metadata was read as application/x-emsg and not able to access data such as ID, and value.

tracks [eventTime=702.96, mediaPos=0.00, window=0, period=0
  group [
    [X] Track:0, id=tracks-v1, mimeType=video/avc, container=video/mp4, bitrate=2344000, codecs=avc1.4d401f, res=1280x720, fps=29.97003, supported=YES
  ]
  group [
    [X] Track:0, id=tracks-a1, mimeType=audio/mp4a-latm, container=audio/mp4, bitrate=128000, codecs=mp4a.40.2, channels=2, sample_rate=48000, language=en, supported=YES
  ]
  group [
    [X] Track:0, id=urn:scte:scte35:2014:xml+bin/, mimeType=application/x-emsg, supported=YES
  ]
]

Media

https://fs01nyc03.mdusolutions.net/CBSNewsLive24/7/index.mpd

Bug Report

• You will email the zip file produced by adb bugreport to android-media-github@google.com after filing this issue.