[Mp4-tech][video][H264] Max. length of Exp-Golomb codes

[J. Miles]

Hi experts,
I have a few related questions regarding the Exp-Golomb codes used in
H.264/ MPEG-4 AVC that I hope someone can help me with:
 1) Is there any limit to the length of Exp-Golomb codes for syntax elements
of types ue(v) and se(v)? This is not clearly stated as such in the
Standard. A 32-bit (signed or unsigned) value would require 63 bits in the
stream. Is an Exp-Golomb code allowed to be longer than 63 bits?
 2) A number of syntax elements are constrained to be in the normal 32-bit
signed range (i.e. -2^31 to 2^31 - 1) - for example the
'offset_for_non_ref_pic' as part of the sequence parameter set RBSP. Are
there any syntax elements that are not constrained in their values, and/or
do any syntax elements allow values outside the 32-bit signed range (thus
requiring more than 63 bits of representation)?
 3) The length and thus the range of one Exp-Golomb code is not known in
advance before parsing it from the bitstream. What should a decoder do in
the case that an Exp-Golomb code that is parsed from the stream results in a
value that is outside the constrained interval for that syntax element? For
example, the syntax element 'pic_order_cnt_type' in the sequence parameter
set RBSP is constrained to be either 0, 1 or 2. But what if the stream is
erroneous (due to bit/packet losses or due to a non-conforming encoder) and
the Exp-Golomb code is parsed to a value outside the range (e.g. a value of
5)?
Thanks.
Jay
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