**Video Renderer Never Gets Ready on Fast Channel Change (Media3 v1.5.1)**

[amit12kumardish]

Description:

I am using Media3 v1.5.1 and a single player instance for playback. On fast channel changes, sometimes the video renderer never gets ready, and playback never starts. Below are the logs of the issue, including video and audio rendering events.

Logs:

downstreamFormat [eventTime=340.76, mediaPos=0.00, window=0, period=0, id=16/1024, mimeType=video/avc, codecs=avc1.640028, res=1440x1080, par=1.333, color=BT709/Limited range/SDR SMPTE 170M/8/8]
videoDecoderInitialized [eventTime=340.90, mediaPos=0.00, window=0, period=0, OMX.bcm.vdec.avc]
videoInputFormat [eventTime=340.91, mediaPos=0.00, window=0, period=0, id=16/1024, mimeType=video/avc, codecs=avc1.640028, res=1440x1080, par=1.333, color=BT709/Limited range/SDR SMPTE 170M/8/8]
downstreamFormat [eventTime=340.91, mediaPos=0.00, window=0, period=0, id=16/1025, mimeType=audio/ac3, bitrate=384000, channels=6, sample_rate=48000, language=en]
audioInputFormat [eventTime=340.91, mediaPos=0.00, window=0, period=0, id=16/1025, mimeType=audio/ac3, bitrate=384000, channels=6, sample_rate=48000, language=en]
rendererReady [eventTime=340.91, mediaPos=0.00, window=0, period=0, rendererIndex=2, text, true]
downstreamFormat [eventTime=340.91, mediaPos=0.00, window=0, period=0, id=null, mimeType=application/x-scte35]
rendererReady [eventTime=340.92, mediaPos=0.00, window=0, period=0, rendererIndex=3, metadata, true]
audioTrackInit [eventTime=341.35, mediaPos=0.00, window=0, period=0, 5,252,48000,false,false,24000]
rendererReady [eventTime=341.35, mediaPos=0.00, window=0, period=0, rendererIndex=1, audio, true]
loading [eventTime=363.64, mediaPos=0.00, window=0, period=0, false]
debug logs: 
onIsLoadingChanged- false :isPlayerStalled false, state: 2
loading [eventTime=495.67, mediaPos=0.00, window=0, period=0, false] 
onIsLoadingChanged- false :isPlayerStalled false, state: 2, playWhenReady: true, bufferedPosition: 22889, bufferedPercentage: 0 isFirstFrameRendered: false

Issue:

The videoRenderer never gets ready during the fast channel change process. From the logs, we can see that the renderer is initialized, but playback does not start, and the rendererReady event never fires for the video , isLoading=false and player never plays.

• rendererReady for video never occurs during channel switch.
• The player seems to be stalled (as per the logs) but playback does not start.
• isFirstFrameRendered is false, indicating no frames have been rendered, despite the video decoder being initialized.

Steps to Reproduce:

1. Switch between multicast channels rapidly.
2. Observe that sometimes the video renderer never gets ready and playback fails to start.

Expected Behavior:

• The video renderer should be ready and playback should start immediately after the channel change.

What I’ve Tried:

• I’ve confirmed that the audio and other renderers are initialized correctly.
• I’ve checked network conditions and they are stable.
• I’m using a single player instance for the playback.

Player Version:

• Media3 version: 1.5.1

---

[amit12kumardish]

// LoadControl
private val minBufferMs = 5000 // 5 seconds of minimum buffer
private val maxBufferMs = 20000 // 20 seconds of maximum buffer
private val bufferForPlaybackMs = 1000 // Buffering required before starting playback
private val bufferForPlaybackAfterRebufferMs = 2000 // Buffering required after rebuffering

[amit12kumardish]

Also, how to use Software Decoders?
How can i check, which decoder is being used?

[linhai326]

Also, how to use Software Decoders? How can i check, which decoder is being used?

• you could extend the MediaCodecSelector class and write your own getDecoderInfos() to return software decoders.
• in callbacks like videoDecoderInitialized, it will print out the decoder you use. for example, in your log,
  videoDecoderInitialized [eventTime=340.90, mediaPos=0.00, window=0, period=0, OMX.bcm.vdec.avc]
  OMX.bcm.vdec.avc is used.

[amit12kumardish]

So omx.bcm is this software or hardware decoder?

…

On Fri, 28 Mar, 2025, 10:21 pm linhai326, ***@***.***> wrote: Also, how to use Software Decoders? How can i check, which decoder is being used? - you could extend the MediaCodecSelector class and write your own getDecoderInfos() to return software decoders. - in callbacks like videoDecoderInitialized, it will print out the decoder you use. for example, in your log, videoDecoderInitialized [eventTime=340.90, mediaPos=0.00, window=0, period=0, OMX.bcm.vdec.avc] OMX.bcm.vdec.avc is used. — Reply to this email directly, view it on GitHub <#2280 (comment)>, or unsubscribe * This message originated outside of DISH and was sent by: ***@***.*** ***@***.***> * ------------------------------ <https://github.com/notifications/unsubscribe-auth/BERVOZXDOWYDGTGTBHZAXZL2WV4YRAVCNFSM6AAAAABZ6UV2C6VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDONRRHEYTCNJVGM> . You are receiving this because you authored the thread.Message ID: ***@***.***> [image: linhai326]*linhai326* left a comment (androidx/media#2280) <#2280 (comment)> Also, how to use Software Decoders? How can i check, which decoder is being used? - you could extend the MediaCodecSelector class and write your own getDecoderInfos() to return software decoders. - in callbacks like videoDecoderInitialized, it will print out the decoder you use. for example, in your log, videoDecoderInitialized [eventTime=340.90, mediaPos=0.00, window=0, period=0, OMX.bcm.vdec.avc] OMX.bcm.vdec.avc is used. — Reply to this email directly, view it on GitHub <#2280 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/BERVOZXDOWYDGTGTBHZAXZL2WV4YRAVCNFSM6AAAAABZ6UV2C6VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDONRRHEYTCNJVGM> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[linhai326]

So omx.bcm is this software or hardware decoder?
…

it should be a hardware decoder. You can take a look at the mediaCodeInfo class:
https://github.com/androidx/media/blob/release/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/mediacodec/MediaCodecInfo.java
check for:
public final boolean hardwareAccelerated;
public final boolean softwareOnly;

[amit12kumardish]

And info, on player not playing All renderers except video renderer is not ready. Why this happening

…

On Fri, 28 Mar, 2025, 10:31 pm linhai326, ***@***.***> wrote: So omx.bcm is this software or hardware decoder? … <#m_-4653863619593798184_> it should be a hardware decoder. You can take a look at the mediaCodeInfo class: https://github.com/androidx/media/blob/release/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/mediacodec/MediaCodecInfo.java check for: public final boolean hardwareAccelerated; public final boolean softwareOnly; — Reply to this email directly, view it on GitHub <#2280 (comment)>, or unsubscribe * This message originated outside of DISH and was sent by: ***@***.*** ***@***.***> * ------------------------------ <https://github.com/notifications/unsubscribe-auth/BERVOZUZVNZVXI6E5Z2J6UT2WV55HAVCNFSM6AAAAABZ6UV2C6VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDONRRHEZTEOBSGU> . You are receiving this because you authored the thread.Message ID: ***@***.***> [image: linhai326]*linhai326* left a comment (androidx/media#2280) <#2280 (comment)> So omx.bcm is this software or hardware decoder? … <#m_-4653863619593798184_> it should be a hardware decoder. You can take a look at the mediaCodeInfo class: https://github.com/androidx/media/blob/release/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/mediacodec/MediaCodecInfo.java check for: public final boolean hardwareAccelerated; public final boolean softwareOnly; — Reply to this email directly, view it on GitHub <#2280 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/BERVOZUZVNZVXI6E5Z2J6UT2WV55HAVCNFSM6AAAAABZ6UV2C6VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDONRRHEZTEOBSGU> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[amit12kumardish]

The videoRenderer never gets ready during the fast channel change process. From the logs, we can see that the renderer is initialized, but playback does not start, and the rendererReady event never fires for the video , isLoading=false and player never plays.

[amit12kumardish]

Can we force media3 to use either Hardware Decoder or Software Decoder?
How Media3 internally selects decoder?
Is there any relation of Tunneling and HW/SW decoders?

[microkatz]

Hi @amit12kumardish

Thank you for reporting your issue. First of all, are you able to reproduce this issue with the ExoPlayer demo application? If yes, could you please supply a bug report of the issue reproduced with the demo application? If you cannot provide it publicly then please send it to [email protected] with the subject Issue #2280.

Can we force media3 to use either Hardware Decoder or Software Decoder?

Yes, you can override the default codec selection processes. Here is a link to another github thread where it is described in additional detail, #1460 (comment).

The app should override [MediaCodecVideoRenderer.getDecoderInfos()] roughly as follows:

protected List<MediaCodecInfo> getDecoderInfos(
      MediaCodecSelector mediaCodecSelector, Format format, boolean requiresSecureDecoder)
      throws DecoderQueryException {
    List<MediaCodecInfo> decoderInfos = super.getDecoderInfos(mediaCodecSelector, format, requiresSecureDecoder);
    if (//Insert condition here like specific sampleMimeType or format resolution) {
        // check if decoderInfos contains the decoder that is ex: hardwareAccelerated
        // if yes, return a copy of the decoderInfos list excluding that decoder
  }

Please also update this issue to indicate you've sent the bug report!