Document decide_ac_pred() and restore_ac_coeffs().

Originally committed as revision 21063 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Michael Niedermayer 2010-01-07 15:43:49 +00:00
parent d6856c5708
commit 616251c924

View File

@ -368,6 +368,15 @@ static inline int get_block_rate(MpegEncContext * s, DCTELEM block[64], int bloc
return rate;
}
/**
* Restores the ac coefficients in block that have been changed by decide_ac_pred().
* This function also restores s->block_last_index.
* @param[in,out] block MB coefficients, these will be restored
* @param[in] dir ac prediction direction for each 8x8 block
* @param[out] st scantable for each 8x8 block
* @param[in] zigzag_last_index index refering to the last non zero coefficient in zigzag order
*/
static inline void restore_ac_coeffs(MpegEncContext * s, DCTELEM block[6][64], int dir[6], uint8_t *st[6], int zigzag_last_index[6])
{
int i, n;
@ -393,6 +402,11 @@ static inline void restore_ac_coeffs(MpegEncContext * s, DCTELEM block[6][64], i
/**
* Returns the optimal value (0 or 1) for the ac_pred element for the given MB in mpeg4.
* This function will also update s->block_last_index and s->ac_val.
* @param[in,out] block MB coefficients, these will be updated if 1 is returned
* @param[in] dir ac prediction direction for each 8x8 block
* @param[out] st scantable for each 8x8 block
* @param[out] zigzag_last_index index refering to the last non zero coefficient in zigzag order
*/
static inline int decide_ac_pred(MpegEncContext * s, DCTELEM block[6][64], int dir[6], uint8_t *st[6], int zigzag_last_index[6])
{