Revision 45e3c163 libavutil/crc.c

View differences:

libavutil/crc.c
37 37 
 * Inits a crc table.
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 * @param ctx must be an array of sizeof(AVCRC)*257 or sizeof(AVCRC)*1024
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 * @param cts_size size of ctx in bytes
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 * @param le if 1, lowest bit represents coefficient for highest exponent
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 *           of corresponding polynomial (both for poly and actual CRC).
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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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 *           bswap_32(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
40 49 
 * @return <0 on failure
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 */
42 51 
int av_crc_init(AVCRC *ctx, int le, int bits, uint32_t poly, int ctx_size){
......
70 79 
    return 0;
71 80 
}
72 81 

  		




  
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/**


  		




  
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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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 *


  		




  
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 * @see av_crc_init() "le" parameter


  		




  
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 */


  		




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uint32_t av_crc(const AVCRC *ctx, uint32_t crc, const uint8_t *buffer, size_t length){


  		




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    const uint8_t *end= buffer+length;


  		




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