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AV_CRC_MAX, /*< Not part of public API! Do not use outside libavutil. */
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* Initialize a CRC table.
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* @param ctx must be an array of size sizeof(AVCRC)*257 or sizeof(AVCRC)*1024
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* @param le If 1, the lowest bit represents the coefficient for the highest
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* exponent of the corresponding polynomial (both for poly and
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* If 0, you must swap the CRC parameter and the result of av_crc
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* if you need the standard representation (can be simplified in
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* most cases to e.g. bswap16):
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* av_bswap32(crc << (32-bits))
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* @param bits number of bits for the CRC
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* @param poly generator polynomial without the x**bits coefficient, in the
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* representation as specified by le
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* @param ctx_size size of ctx in bytes
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* @return <0 on failure
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int av_crc_init(AVCRC *ctx, int le, int bits, uint32_t poly, int ctx_size);
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* Get an initialized standard CRC table.
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* @param crc_id ID of a standard CRC
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* @return a pointer to the CRC table or NULL on failure
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const AVCRC *av_crc_get_table(AVCRCId crc_id);
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uint32_t av_crc(const AVCRC *ctx, uint32_t start_crc, const uint8_t *buffer, size_t length) av_pure;
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* Calculate the CRC of a block.
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* @param crc CRC of previous blocks if any or initial value for CRC
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* @return CRC updated with the data from the given block
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* @see av_crc_init() "le" parameter
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uint32_t av_crc(const AVCRC *ctx, uint32_t crc,
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const uint8_t *buffer, size_t length) av_pure;
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#endif /* AVUTIL_CRC_H */
added
removed
libavutil/crc.h
