>From b08b4a38c87000fe5549de96f65de6ba77740b30 Mon Sep 17 00:00:00 2001
From: Zeng Zhaoxiu <zhaoxiu.z...@gmail.com>
Date: Fri, 13 Feb 2015 23:52:29 +0800
Subject: [PATCH 2/3] avcodec/wmalosslessdec: optimize sign operation
Signed-off-by: Zeng Zhaoxiu <zhaoxiu.z...@gmail.com>
---
libavcodec/wmalosslessdec.c | 34 ++++++++--------------------------
1 file changed, 8 insertions(+), 26 deletions(-)
diff --git a/libavcodec/wmalosslessdec.c b/libavcodec/wmalosslessdec.c
index 9bd5e7b..1916594 100644
--- a/libavcodec/wmalosslessdec.c
+++ b/libavcodec/wmalosslessdec.c
@@ -175,6 +175,8 @@ typedef struct WmallDecodeCtx {
int channel_coeffs[WMALL_MAX_CHANNELS][WMALL_BLOCK_MAX_SIZE];
} WmallDecodeCtx;
+/** Get sign of integer (1 for positive, -1 for negative and 0 for zero) */
+#define WMASIGN(x) ((x > 0) - (x < 0))
static av_cold int decode_init(AVCodecContext *avctx)
{
@@ -631,22 +633,14 @@ static void mclms_update(WmallDecodeCtx *s, int icoef,
int *pred)
for (i = 0; i < order * num_channels; i++)
s->mclms_coeffs[i + ich * order * num_channels] +=
s->mclms_updates[s->mclms_recent + i];
- for (j = 0; j < ich; j++) {
- if (s->channel_residues[j][icoef] > 0)
- s->mclms_coeffs_cur[ich * num_channels + j] += 1;
- else if (s->channel_residues[j][icoef] < 0)
- s->mclms_coeffs_cur[ich * num_channels + j] -= 1;
- }
+ for (j = 0; j < ich; j++)
+ s->mclms_coeffs_cur[ich * num_channels + j] +=
WMASIGN(s->channel_residues[j][icoef]);
} else if (pred_error < 0) {
for (i = 0; i < order * num_channels; i++)
s->mclms_coeffs[i + ich * order * num_channels] -=
s->mclms_updates[s->mclms_recent + i];
- for (j = 0; j < ich; j++) {
- if (s->channel_residues[j][icoef] > 0)
- s->mclms_coeffs_cur[ich * num_channels + j] -= 1;
- else if (s->channel_residues[j][icoef] < 0)
- s->mclms_coeffs_cur[ich * num_channels + j] += 1;
- }
+ for (j = 0; j < ich; j++)
+ s->mclms_coeffs_cur[ich * num_channels + j] -=
WMASIGN(s->channel_residues[j][icoef]);
}
}
@@ -658,11 +652,7 @@ static void mclms_update(WmallDecodeCtx *s, int icoef, int
*pred)
else if (s->channel_residues[ich][icoef] < -range)
s->mclms_prevvalues[s->mclms_recent] = -range;
- s->mclms_updates[s->mclms_recent] = 0;
- if (s->channel_residues[ich][icoef] > 0)
- s->mclms_updates[s->mclms_recent] = 1;
- else if (s->channel_residues[ich][icoef] < 0)
- s->mclms_updates[s->mclms_recent] = -1;
+ s->mclms_updates[s->mclms_recent] =
WMASIGN(s->channel_residues[ich][icoef]);
}
if (s->mclms_recent == 0) {
@@ -724,12 +714,7 @@ static void lms_update(WmallDecodeCtx *s, int ich, int
ilms, int input)
}
s->cdlms[ich][ilms].lms_prevvalues[recent] = av_clip(input, -range, range
- 1);
- if (!input)
- s->cdlms[ich][ilms].lms_updates[recent] = 0;
- else if (input < 0)
- s->cdlms[ich][ilms].lms_updates[recent] = -s->update_speed[ich];
- else
- s->cdlms[ich][ilms].lms_updates[recent] = s->update_speed[ich];
+ s->cdlms[ich][ilms].lms_updates[recent] = WMASIGN(input) *
s->update_speed[ich];
s->cdlms[ich][ilms].lms_updates[recent + (order >> 4)] >>= 2;
s->cdlms[ich][ilms].lms_updates[recent + (order >> 3)] >>= 1;
@@ -773,9 +758,6 @@ static void use_normal_update_speed(WmallDecodeCtx *s, int
ich)
s->update_speed[ich] = 8;
}
-/** Get sign of integer (1 for positive, -1 for negative and 0 for zero) */
-#define WMASIGN(x) ((x > 0) - (x < 0))
-
static void revert_cdlms(WmallDecodeCtx *s, int ch,
int coef_begin, int coef_end)
{
--
2.1.0
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