Deformation issue of graphic subtitles on mobile phones

[360060316]

Version

Media3 1.6.1

More version details

Playing videos with graphic subtitles on mobile phones may cause distortion and incorrect proportions of the graphic subtitles

Devices that reproduce the issue

Android 14

Devices that do not reproduce the issue

No response

Reproducible in the demo app?

Yes

Reproduction steps

Play graphic subtitle videos

Expected result

Play graphic subtitle videos

Actual result

Play graphic subtitle videos

Media

Play graphic subtitle videos

Bug Report

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

[tianyif]

Hi @360060316,

Could you please share the media that can reproduce this issue? If you're unable to share it publicly, please send them to android-media-github@google.com with the subject Issue #2446. Please also update this issue to indicate you've done this.

[360060316]

Hi @360060316,  你好

Could you please share the media that can reproduce this issue? If you're unable to share it publicly, please send them to android-media-github@google.com with the subject Issue #2446. Please also update this issue to indicate you've done this.您能否分享可以重现此问题的媒体？如果您无法公开共享，请将其发送给主题为 Issue #2446 的 android-media-github@google.com。请同时更新此问题以表明您已完成此作。

As long as it is a graphic subtitle, it can be deformed without the need for a specific video

[tianyif]

@360060316, we still need a video with the graphic subtitle, so that we can reproduce this issue and investigate what's wrong with the subtitle.

[360060316]

@360060316, we still need a video with the graphic subtitle, so that we can reproduce this issue and investigate what's wrong with the subtitle.

http://test.oxxxo.ggff.net/stream/fct/playlist.m3u8

[icbaker]

http://test.oxxxo.ggff.net/stream/fct/playlist.m3u8

I played this URL in the demo app, selected the subtitles labelled 'Chinese' and saw subtitles appear on screen. I'm afraid I'm not familiar enough with Chinese to say with certainty that they are not deformed, but they look relatively 'normal' to me. Please could you provide more detail about the deformation you're observing? It would be helpful to include screenshots of what you expect the subtitles to look like, and what they actually look like.

If you'd like us to debug this more quickly, please also provide a VOD stream rather than live - as it's much easier to reproduce the same issue again and again with VOD - which is very important for more subtle issues like visual display.

This is what i see in the demo app on a Pixel 7a running Android 15:

[360060316]

http://test.oxxxo.ggff.net/stream/fct/playlist.m3u8

I played this URL in the demo app, selected the subtitles labelled 'Chinese' and saw subtitles appear on screen. I'm afraid I'm not familiar enough with Chinese to say with certainty that they are not deformed, but they look relatively 'normal' to me. Please could you provide more detail about the deformation you're observing? It would be helpful to include screenshots of what you expect the subtitles to look like, and what they actually look like.

If you'd like us to debug this more quickly, please also provide a VOD stream rather than live - as it's much easier to reproduce the same issue again and again with VOD - which is very important for more subtle issues like visual display.

This is what i see in the demo app on a Pixel 7a running Android 15:

I just confirmed that using androidx.media3.ui.SubtitleView will cause deformation