ffmpeg | branch: master | zhaoxiu.zeng <[email protected]> | Sat Feb 14 00:56:28 2015 +0800| [ac7fc444eed553d5010c5860f2e91bfa42628e08] | committer: Michael Niedermayer
avcodec/apedec: simplify sign conversion Signed-off-by: Zeng Zhaoxiu <[email protected]> Signed-off-by: Michael Niedermayer <[email protected]> > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=ac7fc444eed553d5010c5860f2e91bfa42628e08 --- libavcodec/apedec.c | 23 +++++------------------ 1 file changed, 5 insertions(+), 18 deletions(-) diff --git a/libavcodec/apedec.c b/libavcodec/apedec.c index f1ddf80..536361c 100644 --- a/libavcodec/apedec.c +++ b/libavcodec/apedec.c @@ -505,10 +505,7 @@ static inline int ape_decode_value_3860(APEContext *ctx, GetBitContext *gb, rice->k++; /* Convert to signed */ - if (x & 1) - return (x >> 1) + 1; - else - return -(x >> 1); + return ((x >> 1) ^ ((x & 1) - 1)) + 1; } static inline int ape_decode_value_3900(APEContext *ctx, APERice *rice) @@ -542,10 +539,7 @@ static inline int ape_decode_value_3900(APEContext *ctx, APERice *rice) update_rice(rice, x); /* Convert to signed */ - if (x & 1) - return (x >> 1) + 1; - else - return -(x >> 1); + return ((x >> 1) ^ ((x & 1) - 1)) + 1; } static inline int ape_decode_value_3990(APEContext *ctx, APERice *rice) @@ -588,10 +582,7 @@ static inline int ape_decode_value_3990(APEContext *ctx, APERice *rice) update_rice(rice, x); /* Convert to signed */ - if (x & 1) - return (x >> 1) + 1; - else - return -(x >> 1); + return ((x >> 1) ^ ((x & 1) - 1)) + 1; } static void decode_array_0000(APEContext *ctx, GetBitContext *gb, @@ -634,12 +625,8 @@ static void decode_array_0000(APEContext *ctx, GetBitContext *gb, } } - for (i = 0; i < blockstodecode; i++) { - if (out[i] & 1) - out[i] = (out[i] >> 1) + 1; - else - out[i] = -(out[i] >> 1); - } + for (i = 0; i < blockstodecode; i++) + out[i] = ((out[i] >> 1) ^ ((out[i] & 1) - 1)) + 1; } static void entropy_decode_mono_0000(APEContext *ctx, int blockstodecode) _______________________________________________ ffmpeg-cvslog mailing list [email protected] http://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog
