How do I get the effect of BlendMode.srcOver without making the rounded edges of Image to pointed ones?

Question

I have a Container() that has a background image. This image already has rounded corners, so I haven't used any borderRadius. I want to add a color filter to this image with some opacity. So, I have used this :

Container(
    decoration: BoxDecoration(
        image: DecorationImage(
            image: AssetImage("assets/images/signup_bg.png"),
            fit: BoxFit.contain,
            colorFilter: ColorFilter.mode(
              Color(0xFFEDDFD0).withOpacity(0.80),
              BlendMode.srcOver,
            )),
        color: Color(0xFFE5E5E5),
      ),
),

Now, if used BlendMode.modulate, then the corners of the image remain rounded but the color of the filter changes a bit even if I keep Color(0xFFEDDFD0) as the same. How do i achieve the effect of BlenMode.srcOver without making the rounded edges of the image turn into pointed edges.

PS: Also, in my case I can't change the fit property to anything other than BoxFit.contain.