From bbe68fbd2a6c2c300568c19a09fb33b019502368 Mon Sep 17 00:00:00 2001
From: Jingning Han <jingning@google.com>
Date: Fri, 15 Nov 2013 20:32:03 -0800
Subject: [PATCH] Constrain encoder motion search range
Explicitly constrain the upper limit of motion search range (in the
unit of full pixel) to be [-1023, +1023]. It is intended to control
the effective motion search range for 4K sequences.
Change-Id: I645539c70885eec0f155781f439d97d333336e88
---
vp9/encoder/vp9_firstpass.c | 2 --
vp9/encoder/vp9_mcomp.c | 3 ---
vp9/encoder/vp9_mcomp.h | 5 +++--
3 files changed, 3 insertions(+), 7 deletions(-)
diff --git a/vp9/encoder/vp9_firstpass.c b/vp9/encoder/vp9_firstpass.c
index cbd321b34f..70d711ceee 100644
--- a/vp9/encoder/vp9_firstpass.c
+++ b/vp9/encoder/vp9_firstpass.c
@@ -406,8 +406,6 @@ static void first_pass_motion_search(VP9_COMP *cpi, MACROBLOCK *x,
// for first pass test
while ((quart_frm << sr) < MAX_FULL_PEL_VAL)
sr++;
- if (sr)
- sr--;
step_param += sr;
further_steps -= sr;
diff --git a/vp9/encoder/vp9_mcomp.c b/vp9/encoder/vp9_mcomp.c
index a52f5b1b0a..a383164983 100644
--- a/vp9/encoder/vp9_mcomp.c
+++ b/vp9/encoder/vp9_mcomp.c
@@ -51,9 +51,6 @@ int vp9_init_search_range(VP9_COMP *cpi, int size) {
while ((size << sr) < MAX_FULL_PEL_VAL)
sr++;
- if (sr)
- sr--;
-
sr += cpi->sf.reduce_first_step_size;
sr = MIN(sr, (cpi->sf.max_step_search_steps - 2));
return sr;
diff --git a/vp9/encoder/vp9_mcomp.h b/vp9/encoder/vp9_mcomp.h
index bcab679c7e..10c2e4fca1 100644
--- a/vp9/encoder/vp9_mcomp.h
+++ b/vp9/encoder/vp9_mcomp.h
@@ -18,8 +18,9 @@
// The maximum number of steps in a step search given the largest
// allowed initial step
#define MAX_MVSEARCH_STEPS 11
-// Max full pel mv specified in 1 pel units
-#define MAX_FULL_PEL_VAL ((1 << (MAX_MVSEARCH_STEPS)) - 1)
+// Max full pel mv specified in the unit of full pixel
+// Enable the use of motion vector in range [-1023, 1023].
+#define MAX_FULL_PEL_VAL ((1 << (MAX_MVSEARCH_STEPS - 1)) - 1)
// Maximum size of the first step in full pel units
#define MAX_FIRST_STEP (1 << (MAX_MVSEARCH_STEPS-1))
// Allowed motion vector pixel distance outside image border
--
GitLab