Color mismatch when re-rendering camera stream [Android]?

[ss9326]

I am working with ARCore and a Sceneform fork (using Filament 1.21) to render an AR scene in Android.

My Task-

1. Take snapshot image from a camera stream (External Texture over a quad).
2. Use image processing (segmentation ML model) to identify objects (eg Apple) on the snapshot image and create a cut-out image of that object.
3. Upload the cut-out image as a Sampler2D Texture to a Material (which simply samples and renders the texture).
4. Create a Renderable entity (3D model of an Apple) with this Material, and render it to the scene over the camera quad.

My Problem-
The colors on the Renderable entity do not match the colors of the object in the original camera stream.

I have tried these but with no success-

• Using both unlit/lit material for the Renderable
• Using inverseTonemap or inverseTonemapSRGB on the sampled Texture in the Renderable's Material (the camera stream's material does use inverseTonemapSRGB on the sampled External Texture)
• Creating the snapshot on a RenderTarget attached to a View with NO Postprocessing+Tonemapping, and then rendering that onto the camera's scene (which does have Postprocessing and Filmic Tonemapping/ColorGrading)

Note-
The cut-out Bitmap image has the correct colors on its own, but once rendered as a Texture for the 3D Renderable entity, the colors look either too dark/light compared to the camera stream.

EDIT- Changed the discussion to a more specific problem. Any help would be greatly appreciated.

[ss9326]

Managed to fix this by setting my View's Tonemapping from Filmic to Linear, but to correct the camera texture's colors I applied the Filmic function in the camera material.

fragment {
    vec3 filmicTonemap(vec3 x) {
        const float a = 2.51;
        const float b = 0.03;
        const float c = 2.43;
        const float d = 0.59;
        const float e = 0.14;
        return (x * (a * x + b)) / (x * (c * x + d) + e);
    }

    void material(inout MaterialInputs material) {
        prepareMaterial(material);
        material.baseColor.rgb = filmicTonemap(inverseTonemapSRGB(texture(materialParams_cameraTexture, getUV0()).rgb));
        material.baseColor.a = 1.f;
    }
}