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/*
* Copyright (c) 2010 The WebM project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "vp9/common/vp9_common.h"
#include "vp9/common/vp9_quant_common.h"
static int dc_qlookup[QINDEX_RANGE];
static int ac_qlookup[QINDEX_RANGE];
#define ACDC_MIN 4
void vp9_init_quant_tables() {
int i;
int current_val = 4;
int last_val = 4;
int ac_val;
for (i = 0; i < QINDEX_RANGE; i++) {
ac_qlookup[i] = current_val;
current_val = (int)(current_val * 1.02);
if (current_val == last_val)
current_val++;
last_val = current_val;
ac_val = ac_qlookup[i];
dc_qlookup[i] = (int)((0.000000305 * ac_val * ac_val * ac_val) +
(-0.00065 * ac_val * ac_val) +
(0.9 * ac_val) + 0.5);
if (dc_qlookup[i] < ACDC_MIN)
dc_qlookup[i] = ACDC_MIN;
}
}
int vp9_dc_quant(int qindex, int delta) {
return dc_qlookup[clamp(qindex + delta, 0, MAXQ)];
}
int vp9_dc_uv_quant(int qindex, int delta) {
return dc_qlookup[clamp(qindex + delta, 0, MAXQ)];
}
int vp9_ac_yquant(int qindex) {
return ac_qlookup[clamp(qindex, 0, MAXQ)];
}
int vp9_ac_uv_quant(int qindex, int delta) {
return ac_qlookup[clamp(qindex + delta, 0, MAXQ)];
}
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