[01.org Celadon] Encoded Frame is not proper , Using Hardware Encoder through Media Codec

Hi, As part of a video app , I am using Hardware Encoder/Decoder through Media Codec. The camera is generating YUYV422 Raw frame , I am converting it to YUV420 using Media SDK VPP Processing. and submitting the YUV420 frame to the Media Codec Encoder. The Encoder is configured as H264, 1080p , COLOR_FormatYUV420Flexible, 1500Kbps, gop 0, Baseline , AVCLevel31, and fps 30. I am submitting the encoded frame to Decoder , But this is not being rendered on the surface. I tried playing the encoded frame using ffplay , but the quality is very poor but no errors. The YUYV422 and YUV420 frames looks good when played through ffplay. It seems the NALReference IDC value is 01 instead of 11 indicating of a B frame. I see the below codes in the generated H264 file , 00 00 00 01 25 being repeated most of the time. 00 00 00 01 27 00 00 00 01 28 00 00 00 01 25 could you please let me know if there are any configuration change's that I am missing in Encoder ? Is there any configuration to avoid generating B frames ? Appreciate any inputs on this . Thanks, Sathish