>From a9bd336e769dee9150ae461ff0c662c7e36119d7 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Alberto=20Delm=C3=A1s?= <[email protected]> Date: Mon, 3 Sep 2012 17:32:01 +0200 Subject: [PATCH 2/2] mss12 and mss2: Avoid unnecessary division and loop
Suggested by Michael Niedermayer <[email protected]> --- libavcodec/mss12.h | 2 +- libavcodec/mss2.c | 3 +-- 2 files changed, 2 insertions(+), 3 deletions(-) diff --git a/libavcodec/mss12.h b/libavcodec/mss12.h index 678a0c0..f5d0366 100644 --- a/libavcodec/mss12.h +++ b/libavcodec/mss12.h @@ -103,7 +103,7 @@ av_cold int ff_mss12_decode_end(MSS12Context *ctx); static int arith ## VERSION ## _get_bit(ArithCoder *c) \ { \ int range = c->high - c->low + 1; \ - int bit = (((c->value - c->low) << 1) + 1) / range; \ + int bit = 2 * c->value - c->low >= c->high; \ \ if (bit) \ c->low += range >> 1; \ diff --git a/libavcodec/mss2.c b/libavcodec/mss2.c index 9914562..fbdc72c 100644 --- a/libavcodec/mss2.c +++ b/libavcodec/mss2.c @@ -335,8 +335,7 @@ static int decode_rle(GetBitContext *gb, uint8_t *pal_dst, int pal_stride, else repeat = get_bits(gb, b); - while (b--) - repeat += 1 << b; + repeat += (1 << b) - 1; if (last_symbol == -2) { int skip = FFMIN(repeat, pal_dst + w - pp); -- 1.7.5.1
_______________________________________________ libav-devel mailing list [email protected] https://lists.libav.org/mailman/listinfo/libav-devel
