/media/libvpx/vp8/encoder/psnr.c

http://github.com/zpao/v8monkey · C · 31 lines · 15 code · 7 blank · 9 comment · 2 complexity · e3df6226b9550357841092e1d266a05d MD5 · raw file

  1. /*
  2. * Copyright (c) 2010 The WebM project authors. All Rights Reserved.
  3. *
  4. * Use of this source code is governed by a BSD-style license
  5. * that can be found in the LICENSE file in the root of the source
  6. * tree. An additional intellectual property rights grant can be found
  7. * in the file PATENTS. All contributing project authors may
  8. * be found in the AUTHORS file in the root of the source tree.
  9. */
  10. #include "vpx_scale/yv12config.h"
  11. #include "math.h"
  12. #include "vp8/common/systemdependent.h" /* for vp8_clear_system_state() */
  13. #define MAX_PSNR 60
  14. double vp8_mse2psnr(double Samples, double Peak, double Mse)
  15. {
  16. double psnr;
  17. if ((double)Mse > 0.0)
  18. psnr = 10.0 * log10(Peak * Peak * Samples / Mse);
  19. else
  20. psnr = MAX_PSNR; // Limit to prevent / 0
  21. if (psnr > MAX_PSNR)
  22. psnr = MAX_PSNR;
  23. return psnr;
  24. }