From b4dc6dccbaea08fc0d41e99b020ee1e0e9ff301b Mon Sep 17 00:00:00 2001 From: Anton Khirnov Date: Fri, 2 Nov 2012 10:58:36 +0100 Subject: crc: move doxy to the header --- libavutil/crc.h | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) (limited to 'libavutil/crc.h') diff --git a/libavutil/crc.h b/libavutil/crc.h index 5c25607bbc..142a5b5e8f 100644 --- a/libavutil/crc.h +++ b/libavutil/crc.h @@ -36,8 +36,38 @@ typedef enum { AV_CRC_MAX, /*< Not part of public API! Do not use outside libavutil. */ }AVCRCId; +/** + * Initialize a CRC table. + * @param ctx must be an array of size sizeof(AVCRC)*257 or sizeof(AVCRC)*1024 + * @param le If 1, the lowest bit represents the coefficient for the highest + * exponent of the corresponding polynomial (both for poly and + * actual CRC). + * If 0, you must swap the CRC parameter and the result of av_crc + * if you need the standard representation (can be simplified in + * most cases to e.g. bswap16): + * av_bswap32(crc << (32-bits)) + * @param bits number of bits for the CRC + * @param poly generator polynomial without the x**bits coefficient, in the + * representation as specified by le + * @param ctx_size size of ctx in bytes + * @return <0 on failure + */ int av_crc_init(AVCRC *ctx, int le, int bits, uint32_t poly, int ctx_size); + +/** + * Get an initialized standard CRC table. + * @param crc_id ID of a standard CRC + * @return a pointer to the CRC table or NULL on failure + */ const AVCRC *av_crc_get_table(AVCRCId crc_id); + +/** + * Calculate the CRC of a block. + * @param crc CRC of previous blocks if any or initial value for CRC + * @return CRC updated with the data from the given block + * + * @see av_crc_init() "le" parameter + */ uint32_t av_crc(const AVCRC *ctx, uint32_t start_crc, const uint8_t *buffer, size_t length) av_pure; #endif /* AVUTIL_CRC_H */ -- cgit v1.2.3