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authorMichael Niedermayer <michaelni@gmx.at>2010-01-07 15:43:49 +0000
committerMichael Niedermayer <michaelni@gmx.at>2010-01-07 15:43:49 +0000
commit616251c924d9ea9bb0fcc4a5cf6ad241873500c6 (patch)
tree0a17249f260489b4a1c7bc917b1f0343606ba265 /libavcodec/h263.c
parentd6856c57084d7ae4f417072cc2b988269dcc8de7 (diff)
Document decide_ac_pred() and restore_ac_coeffs().
Originally committed as revision 21063 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec/h263.c')
-rw-r--r--libavcodec/h263.c14
1 files changed, 14 insertions, 0 deletions
diff --git a/libavcodec/h263.c b/libavcodec/h263.c
index a3426ceb4d..198b34682e 100644
--- a/libavcodec/h263.c
+++ b/libavcodec/h263.c
@@ -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])
{