Support format changes in Transformer

[dorobonneko]

Version

Media3 1.9.2

More version details

No response

Devices that reproduce the issue

redmi k20 pro
raphael

Devices that do not reproduce the issue

No response

Reproducible in the demo app?

Yes

Reproduction steps

		trans=new Transformer.Builder(context).build();
		trans.addListener(this);
		trans.start(MediaItem.fromUri(m3u8.getAbsolutePath()),download.getTempPath());

Expected result

Caused by: java.lang.IllegalStateException: Format changes are not supported.
at androidx.media3.transformer.ExoAssetLoaderBaseRenderer.readInput(ExoAssetLoaderBaseRenderer.java:353)

Actual result

当本地m3u8文件中包含部分广告片段，并且广告片段格式与视频本身格式不一致就会抛Caused by: java.lang.IllegalStateException: Format changes are not supported.
at androidx.media3.transformer.ExoAssetLoaderBaseRenderer.readInput(ExoAssetLoaderBaseRenderer.java:353)
希望可以允许跳过该片段

Media

https://vip.dytt-cinema.com/20260114/45459_8df878a8/3000k/hls/mixed.m3u8

Bug Report

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

[kim-vde]

The problem is that the format of the audio and video tracks change. For video, the codecs value is avc1.640028, then avc1.640032 and then back to avc1.640028. For audio, the sample rate is 48000, then 41000, then back to 48000. This is not supported in Transformer yet.

What you can try to do is implement a custom TrackSelector (which will likely be a DefaultTrackSelector) that makes sure that the track format doesn't change, create a DefaultAssetLoaderFactory using this TrackSelector and then pass it to Transformer.Builder.setAssetLoaderFactory