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Diffstat (limited to 'libavcodec/mpegvideo_enc.c')
-rw-r--r--libavcodec/mpegvideo_enc.c40
1 files changed, 38 insertions, 2 deletions
diff --git a/libavcodec/mpegvideo_enc.c b/libavcodec/mpegvideo_enc.c
index a2061532ae..6fe34b57f8 100644
--- a/libavcodec/mpegvideo_enc.c
+++ b/libavcodec/mpegvideo_enc.c
@@ -4196,6 +4196,42 @@ STOP_TIMER("iterative search")
return last_non_zero;
}
+/**
+ * Permute an 8x8 block according to permuatation.
+ * @param block the block which will be permuted according to
+ * the given permutation vector
+ * @param permutation the permutation vector
+ * @param last the last non zero coefficient in scantable order, used to
+ * speed the permutation up
+ * @param scantable the used scantable, this is only used to speed the
+ * permutation up, the block is not (inverse) permutated
+ * to scantable order!
+ */
+static void block_permute(int16_t *block, uint8_t *permutation,
+ const uint8_t *scantable, int last)
+{
+ int i;
+ int16_t temp[64];
+
+ if (last <= 0)
+ return;
+ //FIXME it is ok but not clean and might fail for some permutations
+ // if (permutation[1] == 1)
+ // return;
+
+ for (i = 0; i <= last; i++) {
+ const int j = scantable[i];
+ temp[j] = block[j];
+ block[j] = 0;
+ }
+
+ for (i = 0; i <= last; i++) {
+ const int j = scantable[i];
+ const int perm_j = permutation[j];
+ block[perm_j] = temp[j];
+ }
+}
+
int ff_dct_quantize_c(MpegEncContext *s,
int16_t *block, int n,
int qscale, int *overflow)
@@ -4271,8 +4307,8 @@ int ff_dct_quantize_c(MpegEncContext *s,
/* we need this permutation so that we correct the IDCT, we only permute the !=0 elements */
if (s->idsp.perm_type != FF_IDCT_PERM_NONE)
- ff_block_permute(block, s->idsp.idct_permutation,
- scantable, last_non_zero);
+ block_permute(block, s->idsp.idct_permutation,
+ scantable, last_non_zero);
return last_non_zero;
}