codec/h264/h264dec: wrote explantory comment for neglectance of io.EOF error when peeking in RBSP parsing process

codec/h264/h264dec/nalunit.go

@@ -262,6 +262,11 @@ func NewNALUnit(br *bits.BitReader) (*NALUnit, error) {
 
 	for moreRBSPData(br) {
 		next3Bytes, err := br.PeekBits(24)
+
+		// If PeekBits cannot get 3 bytes, but there still might be 2 bytes left in
+		// the source, we will get an io.EOF; we wish to ignore this and continue.
+		// The call to moreRBSPData will determine when we have reached the end of
+		// the NAL unit.
 		if err != nil && errors.Cause(err) != io.EOF {
 			return nil, errors.Wrap(err, "could not Peek next 3 bytes")
 		}