[FFmpeg-cvslog] avcodec/vc1_block: Simplify dcdiff initialization
zhaoxiu.zeng
git at videolan.org
Sat Feb 28 15:22:06 CET 2015
ffmpeg | branch: master | zhaoxiu.zeng <zhaoxiu.zeng at gmail.com> | Wed Feb 25 00:28:45 2015 +0800| [ccad34e3cae6447747ec2223cffea324123fa68a] | committer: Michael Niedermayer
avcodec/vc1_block: Simplify dcdiff initialization
Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=ccad34e3cae6447747ec2223cffea324123fa68a
---
libavcodec/vc1_block.c | 36 ++++++++++++------------------------
1 file changed, 12 insertions(+), 24 deletions(-)
diff --git a/libavcodec/vc1_block.c b/libavcodec/vc1_block.c
index 7f65744..05361ba 100644
--- a/libavcodec/vc1_block.c
+++ b/libavcodec/vc1_block.c
@@ -571,16 +571,12 @@ static int vc1_decode_i_block(VC1Context *v, int16_t block[64], int n,
return -1;
}
if (dcdiff) {
+ const int m = (v->pq == 1 || v->pq == 2) ? 3 - v->pq : 0;
if (dcdiff == 119 /* ESC index value */) {
- /* TODO: Optimize */
- if (v->pq == 1) dcdiff = get_bits(gb, 10);
- else if (v->pq == 2) dcdiff = get_bits(gb, 9);
- else dcdiff = get_bits(gb, 8);
+ dcdiff = get_bits(gb, 8 + m);
} else {
- if (v->pq == 1)
- dcdiff = (dcdiff << 2) + get_bits(gb, 2) - 3;
- else if (v->pq == 2)
- dcdiff = (dcdiff << 1) + get_bits1(gb) - 1;
+ if (m)
+ dcdiff = (dcdiff << m) + get_bits(gb, m) - ((1 << m) - 1);
}
if (get_bits1(gb))
dcdiff = -dcdiff;
@@ -739,16 +735,12 @@ static int vc1_decode_i_block_adv(VC1Context *v, int16_t block[64], int n,
return -1;
}
if (dcdiff) {
+ const int m = (mquant == 1 || mquant == 2) ? 3 - mquant : 0;
if (dcdiff == 119 /* ESC index value */) {
- /* TODO: Optimize */
- if (mquant == 1) dcdiff = get_bits(gb, 10);
- else if (mquant == 2) dcdiff = get_bits(gb, 9);
- else dcdiff = get_bits(gb, 8);
+ dcdiff = get_bits(gb, 8 + m);
} else {
- if (mquant == 1)
- dcdiff = (dcdiff << 2) + get_bits(gb, 2) - 3;
- else if (mquant == 2)
- dcdiff = (dcdiff << 1) + get_bits1(gb) - 1;
+ if (m)
+ dcdiff = (dcdiff << m) + get_bits(gb, m) - ((1 << m) - 1);
}
if (get_bits1(gb))
dcdiff = -dcdiff;
@@ -960,16 +952,12 @@ static int vc1_decode_intra_block(VC1Context *v, int16_t block[64], int n,
return -1;
}
if (dcdiff) {
+ const int m = (mquant == 1 || mquant == 2) ? 3 - mquant : 0;
if (dcdiff == 119 /* ESC index value */) {
- /* TODO: Optimize */
- if (mquant == 1) dcdiff = get_bits(gb, 10);
- else if (mquant == 2) dcdiff = get_bits(gb, 9);
- else dcdiff = get_bits(gb, 8);
+ dcdiff = get_bits(gb, 8 + m);
} else {
- if (mquant == 1)
- dcdiff = (dcdiff << 2) + get_bits(gb, 2) - 3;
- else if (mquant == 2)
- dcdiff = (dcdiff << 1) + get_bits1(gb) - 1;
+ if (m)
+ dcdiff = (dcdiff << m) + get_bits(gb, m) - ((1 << m) - 1);
}
if (get_bits1(gb))
dcdiff = -dcdiff;
More information about the ffmpeg-cvslog
mailing list