libavcodec/extract_extradata_bsf.c:119: error: Uninitialized Value
  The value read from filtered_data was never initialized.

libavcodec/extract_extradata_bsf.c:119:17: 
117.                 AV_WB24(filtered_data, 1); // startcode
118.                 memcpy(filtered_data + 3, nal->raw_data, nal->raw_size);
119.                 filtered_data += 3 + nal->raw_size;
                     ^
120.             }
121.         }
