diff --git a/libavcodec/bitstream.h b/libavcodec/bitstream.h index c516c3c20b..d41d5ec60b 100644 --- a/libavcodec/bitstream.h +++ b/libavcodec/bitstream.h @@ -969,4 +969,50 @@ static inline int decode012(GetBitContext *gb){ return get_bits1(gb) + 1; } +/** + * Get unary code of limited length + * @todo FIXME Slow and ugly + * @param gb GetBitContext + * @param[in] stop The bitstop value (unary code of 1's or 0's) + * @param[in] len Maximum length + * @return Unary length/index + */ +static int get_unary(GetBitContext *gb, int stop, int len) +{ +#if 1 + int i; + + for(i = 0; i < len && get_bits1(gb) != stop; i++); + return i; +/* int i = 0, tmp = !stop; + + while (i != len && tmp != stop) + { + tmp = get_bits(gb, 1); + i++; + } + if (i == len && tmp != stop) return len+1; + return i;*/ +#else + unsigned int buf; + int log; + + OPEN_READER(re, gb); + UPDATE_CACHE(re, gb); + buf=GET_CACHE(re, gb); //Still not sure + if (stop) buf = ~buf; + + log= av_log2(-buf); //FIXME: -? + if (log < limit){ + LAST_SKIP_BITS(re, gb, log+1); + CLOSE_READER(re, gb); + return log; + } + + LAST_SKIP_BITS(re, gb, limit); + CLOSE_READER(re, gb); + return limit; +#endif +} + #endif /* BITSTREAM_H */