vpx/vp8/encoder/psnr.c
Yaowu Xu 28765690fe Changed MAX_PSNR to 100
The MAX_PSNR was used to assign a "psnr" number when the mse is close
to zero. The direct assignment is used to prevent divide by zero in
computation. Changing it from 60 to 100 to be consistent against what
is being done in VP9

Change-Id: I4854ffc4961e59d372ec8005a0d52ca46e3c4c1a
2012-12-18 14:36:20 -08:00

32 lines
866 B
C

/*
* 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 "vpx_scale/yv12config.h"
#include "math.h"
#include "vp8/common/systemdependent.h" /* for vp8_clear_system_state() */
#define MAX_PSNR 100
double vp8_mse2psnr(double Samples, double Peak, double Mse)
{
double psnr;
if ((double)Mse > 0.0)
psnr = 10.0 * log10(Peak * Peak * Samples / Mse);
else
psnr = MAX_PSNR; /* Limit to prevent / 0 */
if (psnr > MAX_PSNR)
psnr = MAX_PSNR;
return psnr;
}