[Bug]: FIT scale mode does not work correctly

[tukez]

Version

3.1.2

Environment that reproduces the issue

OnePlus 12

RTMP/SRT/... Server

SRT

Audio configuration

No response

Video configuration

• H.264
• 1280x720

Is it reproducible in the demos application?

Yes

Reproduction steps

Change the scale mode in the StreamPack boilerplate app to FIT and start streaming.

Expected result

The image on the phone is with black bars on top and bottom.

Actual result

Image on the phone is fullscreen and cropped of left/right compared to the stream.

Phone:

Stream:

Additional context

No response

Relevant logs output

[ThibaultBee]

The scale mode only concerns the Preview.
There is no way to change it on the stream yet.
Duplicates #277

[tukez]

The preview view scaling is wrong. @ThibaultBee

[ThibaultBee]

Ok, I need to have a look on the API.
The Preview package relies on camerax viewfinder package. Thus, either:

• it is a binding issue, I will be able to fix it
• it is an error from the viewfinder package, it is going to be far more difficult. I made a branch where I updated the version on the viewfinder package. It might help.

[ThibaultBee]

The binding seems correct: https://github.com/ThibaultBee/StreamPack/blob/main/ui/src/main/java/io/github/thibaultbee/streampack/ui/views/PreviewView.kt
Also the link to related camerax doc: https://developer.android.com/media/camera/camerax/preview#scale-type

[ThibaultBee]

How do you set scale mode?

[tukez]

I tried to set both from layout file and in code.

[ThibaultBee]

The video configuration of 1280x720 does not apply to the preview. I agree it might be confusing.

The Preview adapts its resolution according to the size of its parent.
If you want the same aspect ratio for the stream and the preview. A solution is to create a View parent with the same aspect ratio of the stream.

[tukez]

I am creating a parent with the correct aspect ratio. That is not the problem though, the problem is that in FIT-mode the image is cropped.

[ThibaultBee]

Hi, I tried to reproduce with the activity_main.xml:

   <io.github.thibaultbee.streampack.ui.views.PreviewView
        android:id="@+id/preview"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:scaleMode="fit"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

And it actually fits. Did I miss something?

See

[Dustinhoefer]

I am also running into the same issue:

on the srt server there is more image content on left and right.
How can I help you debugging @ThibaultBee ?

S24 Ultra (aspect ratio 19.5:9)
OPs Oneplus 12 has aspect ration of 19.8:9

The boilerplate project has this issue as well :)

Also the on the srt server is compressed on the x axis / stretched on the y axis