Answer

1.Adjust stream settings on [Image] window
- Increase the value of [Max bit rate (per client)]
e.g. from 3M to 6M or 8M
- Increase [Image quality]
e.g. from 5M to 3 in case of VBR

When the image still remains blurry, change the following setting on the [Image quality] window.
2.Adjust [DNR]
e.g. from 128 to 112

When sharpness is still insufficient, set the following on [Image quality] window.
3.Increase Sharpness level/Aperture level.
e.g. from 16 to 21 (Sharpness increases. but noise also increases).