Why the best preview's resolution is high?

[askarsyzdykov]

I have a problem with quality of preview on Android devices, it's worse than pre-installed Camera app.

In the file https://github.com/flutter/plugins/blob/master/packages/camera/android/src/main/java/io/flutter/plugins/camera/CameraUtils.java:

static Size computeBestPreviewSize(String cameraName, ResolutionPreset preset) {
    if (preset.ordinal() > ResolutionPreset.high.ordinal()) {
      preset = ResolutionPreset.high;
    }

    CamcorderProfile profile =
        getBestAvailableCamcorderProfileForResolutionPreset(cameraName, preset);
    return new Size(profile.videoFrameWidth, profile.videoFrameHeight);
  }

If I delete the row preset = ResolutionPreset.high;, then preview's quality seems good, but on some devices it affects to aspect ratio and preview is wrong scaled.

Logs

[✓] Flutter (Channel unknown, v1.13.6, on Mac OS X 10.15.2 19C57, locale en-RU)
    • Flutter version 1.13.6 at /Users/askarsyzdykov/Development/flutter
    • Framework revision 659dc8129d (4 weeks ago), 2019-12-30 09:24:47 -0800
    • Engine revision bdc9708d23
    • Dart version 2.8.0 (build 2.8.0-dev.0.0 c547f5d933)

 
[✓] Android toolchain - develop for Android devices (Android SDK version 29.0.1)
    • Android SDK at /Users/askarsyzdykov/Library/Android/sdk
    • Android NDK location not configured (optional; useful for native profiling support)
    • Platform android-29, build-tools 29.0.1
    • Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 1.8.0_202-release-1483-b49-5587405)
    • All Android licenses accepted.

[✓] Xcode - develop for iOS and macOS (Xcode 11.3.1)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Xcode 11.3.1, Build version 11C504
    • CocoaPods version 1.8.4

[✓] Android Studio (version 3.5)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Flutter plugin version 42.1.1
    • Dart plugin version 191.8593
    • Java version OpenJDK Runtime Environment (build 1.8.0_202-release-1483-b49-5587405)

[!] IntelliJ IDEA Community Edition (version 2018.3.5)
    • IntelliJ at /Applications/IntelliJ IDEA CE.app
    ✗ Flutter plugin not installed; this adds Flutter specific functionality.
    ✗ Dart plugin not installed; this adds Dart specific functionality.
    • For information about installing plugins, see
      https://flutter.dev/intellij-setup/#installing-the-plugins

[✓] VS Code (version 1.39.2)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.6.0

[✓] Connected device (1 available)
    • SM A500F • 80ba9ad6 • android-arm • Android 6.0.1 (API 23)

! Doctor found issues in 1 category.