source/libvpx/vp9/common/vp9_postproc.c - platform/external/chromium_org/third_party/libvpx - Git at Google

 /*
  *  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 <math.h>
 #include <stdlib.h>
 #include <stdio.h>

 #include "./vpx_config.h"
 #include "./vpx_scale_rtcd.h"
 #include "./vp9_rtcd.h"

 #include "vpx_scale/vpx_scale.h"
 #include "vpx_scale/yv12config.h"

 #include "vp9/common/vp9_onyxc_int.h"
 #include "vp9/common/vp9_postproc.h"
 #include "vp9/common/vp9_systemdependent.h"
 #include "vp9/common/vp9_textblit.h"

 #if CONFIG_VP9_POSTPROC
 static const short kernel5[] = {
   1, 1, 4, 1, 1
 };

 const short vp9_rv[] = {
   8, 5, 2, 2, 8, 12, 4, 9, 8, 3,
   0, 3, 9, 0, 0, 0, 8, 3, 14, 4,
   10, 1, 11, 14, 1, 14, 9, 6, 12, 11,
   8, 6, 10, 0, 0, 8, 9, 0, 3, 14,
   8, 11, 13, 4, 2, 9, 0, 3, 9, 6,
   1, 2, 3, 14, 13, 1, 8, 2, 9, 7,
   3, 3, 1, 13, 13, 6, 6, 5, 2, 7,
   11, 9, 11, 8, 7, 3, 2, 0, 13, 13,
   14, 4, 12, 5, 12, 10, 8, 10, 13, 10,
   4, 14, 4, 10, 0, 8, 11, 1, 13, 7,
   7, 14, 6, 14, 13, 2, 13, 5, 4, 4,
   0, 10, 0, 5, 13, 2, 12, 7, 11, 13,
   8, 0, 4, 10, 7, 2, 7, 2, 2, 5,
   3, 4, 7, 3, 3, 14, 14, 5, 9, 13,
   3, 14, 3, 6, 3, 0, 11, 8, 13, 1,
   13, 1, 12, 0, 10, 9, 7, 6, 2, 8,
   5, 2, 13, 7, 1, 13, 14, 7, 6, 7,
   9, 6, 10, 11, 7, 8, 7, 5, 14, 8,
   4, 4, 0, 8, 7, 10, 0, 8, 14, 11,
   3, 12, 5, 7, 14, 3, 14, 5, 2, 6,
   11, 12, 12, 8, 0, 11, 13, 1, 2, 0,
   5, 10, 14, 7, 8, 0, 4, 11, 0, 8,
   0, 3, 10, 5, 8, 0, 11, 6, 7, 8,
   10, 7, 13, 9, 2, 5, 1, 5, 10, 2,
   4, 3, 5, 6, 10, 8, 9, 4, 11, 14,
   0, 10, 0, 5, 13, 2, 12, 7, 11, 13,
   8, 0, 4, 10, 7, 2, 7, 2, 2, 5,
   3, 4, 7, 3, 3, 14, 14, 5, 9, 13,
   3, 14, 3, 6, 3, 0, 11, 8, 13, 1,
   13, 1, 12, 0, 10, 9, 7, 6, 2, 8,
   5, 2, 13, 7, 1, 13, 14, 7, 6, 7,
   9, 6, 10, 11, 7, 8, 7, 5, 14, 8,
   4, 4, 0, 8, 7, 10, 0, 8, 14, 11,
   3, 12, 5, 7, 14, 3, 14, 5, 2, 6,
   11, 12, 12, 8, 0, 11, 13, 1, 2, 0,
   5, 10, 14, 7, 8, 0, 4, 11, 0, 8,
   0, 3, 10, 5, 8, 0, 11, 6, 7, 8,
   10, 7, 13, 9, 2, 5, 1, 5, 10, 2,
   4, 3, 5, 6, 10, 8, 9, 4, 11, 14,
   3, 8, 3, 7, 8, 5, 11, 4, 12, 3,
   11, 9, 14, 8, 14, 13, 4, 3, 1, 2,
   14, 6, 5, 4, 4, 11, 4, 6, 2, 1,
   5, 8, 8, 12, 13, 5, 14, 10, 12, 13,
   0, 9, 5, 5, 11, 10, 13, 9, 10, 13,
 };

 void vp9_post_proc_down_and_across_c(const uint8_t *src_ptr,
                                      uint8_t *dst_ptr,
                                      int src_pixels_per_line,
                                      int dst_pixels_per_line,
                                      int rows,
                                      int cols,
                                      int flimit) {
   uint8_t const *p_src;
   uint8_t *p_dst;
   int row;
   int col;
   int i;
   int v;
   int pitch = src_pixels_per_line;
   uint8_t d[8];
   (void)dst_pixels_per_line;

   for (row = 0; row < rows; row++) {
     /* post_proc_down for one row */
     p_src = src_ptr;
     p_dst = dst_ptr;

     for (col = 0; col < cols; col++) {
       int kernel = 4;
       int v = p_src[col];

       for (i = -2; i <= 2; i++) {
         if (abs(v - p_src[col + i * pitch]) > flimit)
           goto down_skip_convolve;

         kernel += kernel5[2 + i] * p_src[col + i * pitch];
       }

       v = (kernel >> 3);
     down_skip_convolve:
       p_dst[col] = v;
     }

     /* now post_proc_across */
     p_src = dst_ptr;
     p_dst = dst_ptr;

     for (i = 0; i < 8; i++)
       d[i] = p_src[i];

     for (col = 0; col < cols; col++) {
       int kernel = 4;
       v = p_src[col];

       d[col & 7] = v;

       for (i = -2; i <= 2; i++) {
         if (abs(v - p_src[col + i]) > flimit)
           goto across_skip_convolve;

         kernel += kernel5[2 + i] * p_src[col + i];
       }

       d[col & 7] = (kernel >> 3);
     across_skip_convolve:

       if (col >= 2)
         p_dst[col - 2] = d[(col - 2) & 7];
     }

     /* handle the last two pixels */
     p_dst[col - 2] = d[(col - 2) & 7];
     p_dst[col - 1] = d[(col - 1) & 7];


     /* next row */
     src_ptr += pitch;
     dst_ptr += pitch;
   }
 }

 static int q2mbl(int x) {
   if (x < 20) x = 20;

   x = 50 + (x - 50) * 10 / 8;
   return x * x / 3;
 }

 void vp9_mbpost_proc_across_ip_c(uint8_t *src, int pitch,
                                  int rows, int cols, int flimit) {
   int r, c, i;

   uint8_t *s = src;
   uint8_t d[16];


   for (r = 0; r < rows; r++) {
     int sumsq = 0;
     int sum   = 0;

     for (i = -8; i <= 6; i++) {
       sumsq += s[i] * s[i];
       sum   += s[i];
       d[i + 8] = 0;
     }

     for (c = 0; c < cols + 8; c++) {
       int x = s[c + 7] - s[c - 8];
       int y = s[c + 7] + s[c - 8];

       sum  += x;
       sumsq += x * y;

       d[c & 15] = s[c];

       if (sumsq * 15 - sum * sum < flimit) {
         d[c & 15] = (8 + sum + s[c]) >> 4;
       }

       s[c - 8] = d[(c - 8) & 15];
     }

     s += pitch;
   }
 }

 void vp9_mbpost_proc_down_c(uint8_t *dst, int pitch,
                             int rows, int cols, int flimit) {
   int r, c, i;
   const short *rv3 = &vp9_rv[63 & rand()]; // NOLINT

   for (c = 0; c < cols; c++) {
     uint8_t *s = &dst[c];
     int sumsq = 0;
     int sum   = 0;
     uint8_t d[16];
     const short *rv2 = rv3 + ((c * 17) & 127);

     for (i = -8; i <= 6; i++) {
       sumsq += s[i * pitch] * s[i * pitch];
       sum   += s[i * pitch];
     }

     for (r = 0; r < rows + 8; r++) {
       sumsq += s[7 * pitch] * s[ 7 * pitch] - s[-8 * pitch] * s[-8 * pitch];
       sum  += s[7 * pitch] - s[-8 * pitch];
       d[r & 15] = s[0];

       if (sumsq * 15 - sum * sum < flimit) {
         d[r & 15] = (rv2[r & 127] + sum + s[0]) >> 4;
       }

       s[-8 * pitch] = d[(r - 8) & 15];
       s += pitch;
     }
   }
 }

 static void deblock_and_de_macro_block(YV12_BUFFER_CONFIG   *source,
                                        YV12_BUFFER_CONFIG   *post,
                                        int                   q,
                                        int                   low_var_thresh,
                                        int                   flag) {
   double level = 6.0e-05 * q * q * q - .0067 * q * q + .306 * q + .0065;
   int ppl = (int)(level + .5);
   (void) low_var_thresh;
   (void) flag;

   vp9_post_proc_down_and_across(source->y_buffer, post->y_buffer,
                                 source->y_stride, post->y_stride,
                                 source->y_height, source->y_width, ppl);

   vp9_mbpost_proc_across_ip(post->y_buffer, post->y_stride, post->y_height,
                             post->y_width, q2mbl(q));

   vp9_mbpost_proc_down(post->y_buffer, post->y_stride, post->y_height,
                        post->y_width, q2mbl(q));

   vp9_post_proc_down_and_across(source->u_buffer, post->u_buffer,
                                 source->uv_stride, post->uv_stride,
                                 source->uv_height, source->uv_width, ppl);
   vp9_post_proc_down_and_across(source->v_buffer, post->v_buffer,
                                 source->uv_stride, post->uv_stride,
                                 source->uv_height, source->uv_width, ppl);
 }

 void vp9_deblock(const YV12_BUFFER_CONFIG *src, YV12_BUFFER_CONFIG *dst,
                  int q) {
   const int ppl = (int)(6.0e-05 * q * q * q - 0.0067 * q * q + 0.306 * q
                         + 0.0065 + 0.5);
   int i;

   const uint8_t *const srcs[3] = {src->y_buffer, src->u_buffer, src->v_buffer};
   const int src_strides[3] = {src->y_stride, src->uv_stride, src->uv_stride};
   const int src_widths[3] = {src->y_width, src->uv_width, src->uv_width};
   const int src_heights[3] = {src->y_height, src->uv_height, src->uv_height};

   uint8_t *const dsts[3] = {dst->y_buffer, dst->u_buffer, dst->v_buffer};
   const int dst_strides[3] = {dst->y_stride, dst->uv_stride, dst->uv_stride};

   for (i = 0; i < MAX_MB_PLANE; ++i)
     vp9_post_proc_down_and_across(srcs[i], dsts[i],
                                   src_strides[i], dst_strides[i],
                                   src_heights[i], src_widths[i], ppl);
 }

 void vp9_denoise(const YV12_BUFFER_CONFIG *src, YV12_BUFFER_CONFIG *dst,
                  int q) {
   const int ppl = (int)(6.0e-05 * q * q * q - 0.0067 * q * q + 0.306 * q
                         + 0.0065 + 0.5);
   int i;

   const uint8_t *const srcs[3] = {src->y_buffer, src->u_buffer, src->v_buffer};
   const int src_strides[3] = {src->y_stride, src->uv_stride, src->uv_stride};
   const int src_widths[3] = {src->y_width, src->uv_width, src->uv_width};
   const int src_heights[3] = {src->y_height, src->uv_height, src->uv_height};

   uint8_t *const dsts[3] = {dst->y_buffer, dst->u_buffer, dst->v_buffer};
   const int dst_strides[3] = {dst->y_stride, dst->uv_stride, dst->uv_stride};

   for (i = 0; i < MAX_MB_PLANE; ++i) {
     const int src_stride = src_strides[i];
     const uint8_t *const src = srcs[i] + 2 * src_stride + 2;
     const int src_width = src_widths[i] - 4;
     const int src_height = src_heights[i] - 4;

     const int dst_stride = dst_strides[i];
     uint8_t *const dst = dsts[i] + 2 * dst_stride + 2;

     vp9_post_proc_down_and_across(src, dst, src_stride, dst_stride,
                                   src_height, src_width, ppl);
   }
 }

 static double gaussian(double sigma, double mu, double x) {
   return 1 / (sigma * sqrt(2.0 * 3.14159265)) *
          (exp(-(x - mu) * (x - mu) / (2 * sigma * sigma)));
 }

 static void fillrd(struct postproc_state *state, int q, int a) {
   char char_dist[300];

   double sigma;
   int ai = a, qi = q, i;

   vp9_clear_system_state();

   sigma = ai + .5 + .6 * (63 - qi) / 63.0;

   /* set up a lookup table of 256 entries that matches
    * a gaussian distribution with sigma determined by q.
    */
   {
     double i;
     int next, j;

     next = 0;

     for (i = -32; i < 32; i++) {
       int a = (int)(0.5 + 256 * gaussian(sigma, 0, i));

       if (a) {
         for (j = 0; j < a; j++) {
           char_dist[next + j] = (char) i;
         }

         next = next + j;
       }
     }

     for (; next < 256; next++)
       char_dist[next] = 0;
   }

   for (i = 0; i < 3072; i++) {
     state->noise[i] = char_dist[rand() & 0xff];  // NOLINT
   }

   for (i = 0; i < 16; i++) {
     state->blackclamp[i] = -char_dist[0];
     state->whiteclamp[i] = -char_dist[0];
     state->bothclamp[i] = -2 * char_dist[0];
   }

   state->last_q = q;
   state->last_noise = a;
 }

 void vp9_plane_add_noise_c(uint8_t *start, char *noise,
                            char blackclamp[16],
                            char whiteclamp[16],
                            char bothclamp[16],
                            unsigned int width, unsigned int height, int pitch) {
   unsigned int i, j;

   // TODO(jbb): why does simd code use both but c doesn't,  normalize and
   // fix..
   (void) bothclamp;
   for (i = 0; i < height; i++) {
     uint8_t *pos = start + i * pitch;
     char  *ref = (char *)(noise + (rand() & 0xff));  // NOLINT

     for (j = 0; j < width; j++) {
       if (pos[j] < blackclamp[0])
         pos[j] = blackclamp[0];

       if (pos[j] > 255 + whiteclamp[0])
         pos[j] = 255 + whiteclamp[0];

       pos[j] += ref[j];
     }
   }
 }

 int vp9_post_proc_frame(struct VP9Common *cm,
                         YV12_BUFFER_CONFIG *dest, vp9_ppflags_t *ppflags) {
   const int q = MIN(63, cm->lf.filter_level * 10 / 6);
   const int flags = ppflags->post_proc_flag;
   YV12_BUFFER_CONFIG *const ppbuf = &cm->post_proc_buffer;
   struct postproc_state *const ppstate = &cm->postproc_state;

   if (!cm->frame_to_show)
     return -1;

   if (!flags) {
     *dest = *cm->frame_to_show;
     return 0;
   }

   vp9_clear_system_state();

 #if CONFIG_VP9_POSTPROC || CONFIG_INTERNAL_STATS
   if (vp9_realloc_frame_buffer(&cm->post_proc_buffer, cm->width, cm->height,
                                cm->subsampling_x, cm->subsampling_y,
                                VP9_DEC_BORDER_IN_PIXELS, NULL, NULL, NULL) < 0)
     vpx_internal_error(&cm->error, VPX_CODEC_MEM_ERROR,
                        "Failed to allocate post-processing buffer");
 #endif

   if (flags & VP9D_DEMACROBLOCK) {
     deblock_and_de_macro_block(cm->frame_to_show, ppbuf,
                                q + (ppflags->deblocking_level - 5) * 10, 1, 0);
   } else if (flags & VP9D_DEBLOCK) {
     vp9_deblock(cm->frame_to_show, ppbuf, q);
   } else {
     vp8_yv12_copy_frame(cm->frame_to_show, ppbuf);
   }

   if (flags & VP9D_ADDNOISE) {
     const int noise_level = ppflags->noise_level;
     if (ppstate->last_q != q ||
         ppstate->last_noise != noise_level) {
       fillrd(ppstate, 63 - q, noise_level);
     }

     vp9_plane_add_noise(ppbuf->y_buffer, ppstate->noise, ppstate->blackclamp,
                         ppstate->whiteclamp, ppstate->bothclamp,
                         ppbuf->y_width, ppbuf->y_height, ppbuf->y_stride);
   }

   *dest = *ppbuf;

   /* handle problem with extending borders */
   dest->y_width = cm->width;
   dest->y_height = cm->height;
   dest->uv_width = dest->y_width >> cm->subsampling_x;
   dest->uv_height = dest->y_height >> cm->subsampling_y;

   return 0;
 }
 #endif
	/*
	* 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 <math.h>
	#include <stdlib.h>
	#include <stdio.h>

	#include "./vpx_config.h"
	#include "./vpx_scale_rtcd.h"
	#include "./vp9_rtcd.h"

	#include "vpx_scale/vpx_scale.h"
	#include "vpx_scale/yv12config.h"

	#include "vp9/common/vp9_onyxc_int.h"
	#include "vp9/common/vp9_postproc.h"
	#include "vp9/common/vp9_systemdependent.h"
	#include "vp9/common/vp9_textblit.h"

	#if CONFIG_VP9_POSTPROC
	static const short kernel5[] = {
	1, 1, 4, 1, 1
	};

	const short vp9_rv[] = {
	8, 5, 2, 2, 8, 12, 4, 9, 8, 3,
	0, 3, 9, 0, 0, 0, 8, 3, 14, 4,
	10, 1, 11, 14, 1, 14, 9, 6, 12, 11,
	8, 6, 10, 0, 0, 8, 9, 0, 3, 14,
	8, 11, 13, 4, 2, 9, 0, 3, 9, 6,
	1, 2, 3, 14, 13, 1, 8, 2, 9, 7,
	3, 3, 1, 13, 13, 6, 6, 5, 2, 7,
	11, 9, 11, 8, 7, 3, 2, 0, 13, 13,
	14, 4, 12, 5, 12, 10, 8, 10, 13, 10,
	4, 14, 4, 10, 0, 8, 11, 1, 13, 7,
	7, 14, 6, 14, 13, 2, 13, 5, 4, 4,
	0, 10, 0, 5, 13, 2, 12, 7, 11, 13,
	8, 0, 4, 10, 7, 2, 7, 2, 2, 5,
	3, 4, 7, 3, 3, 14, 14, 5, 9, 13,
	3, 14, 3, 6, 3, 0, 11, 8, 13, 1,
	13, 1, 12, 0, 10, 9, 7, 6, 2, 8,
	5, 2, 13, 7, 1, 13, 14, 7, 6, 7,
	9, 6, 10, 11, 7, 8, 7, 5, 14, 8,
	4, 4, 0, 8, 7, 10, 0, 8, 14, 11,
	3, 12, 5, 7, 14, 3, 14, 5, 2, 6,
	11, 12, 12, 8, 0, 11, 13, 1, 2, 0,
	5, 10, 14, 7, 8, 0, 4, 11, 0, 8,
	0, 3, 10, 5, 8, 0, 11, 6, 7, 8,
	10, 7, 13, 9, 2, 5, 1, 5, 10, 2,
	4, 3, 5, 6, 10, 8, 9, 4, 11, 14,
	0, 10, 0, 5, 13, 2, 12, 7, 11, 13,
	8, 0, 4, 10, 7, 2, 7, 2, 2, 5,
	3, 4, 7, 3, 3, 14, 14, 5, 9, 13,
	3, 14, 3, 6, 3, 0, 11, 8, 13, 1,
	13, 1, 12, 0, 10, 9, 7, 6, 2, 8,
	5, 2, 13, 7, 1, 13, 14, 7, 6, 7,
	9, 6, 10, 11, 7, 8, 7, 5, 14, 8,
	4, 4, 0, 8, 7, 10, 0, 8, 14, 11,
	3, 12, 5, 7, 14, 3, 14, 5, 2, 6,
	11, 12, 12, 8, 0, 11, 13, 1, 2, 0,
	5, 10, 14, 7, 8, 0, 4, 11, 0, 8,
	0, 3, 10, 5, 8, 0, 11, 6, 7, 8,
	10, 7, 13, 9, 2, 5, 1, 5, 10, 2,
	4, 3, 5, 6, 10, 8, 9, 4, 11, 14,
	3, 8, 3, 7, 8, 5, 11, 4, 12, 3,
	11, 9, 14, 8, 14, 13, 4, 3, 1, 2,
	14, 6, 5, 4, 4, 11, 4, 6, 2, 1,
	5, 8, 8, 12, 13, 5, 14, 10, 12, 13,
	0, 9, 5, 5, 11, 10, 13, 9, 10, 13,
	};

	void vp9_post_proc_down_and_across_c(const uint8_t *src_ptr,
	uint8_t *dst_ptr,
	int src_pixels_per_line,
	int dst_pixels_per_line,
	int rows,
	int cols,
	int flimit) {
	uint8_t const *p_src;
	uint8_t *p_dst;
	int row;
	int col;
	int i;
	int v;
	int pitch = src_pixels_per_line;
	uint8_t d[8];
	(void)dst_pixels_per_line;

	for (row = 0; row < rows; row++) {
	/* post_proc_down for one row */
	p_src = src_ptr;
	p_dst = dst_ptr;

	for (col = 0; col < cols; col++) {
	int kernel = 4;
	int v = p_src[col];

	for (i = -2; i <= 2; i++) {
	if (abs(v - p_src[col + i * pitch]) > flimit)
	goto down_skip_convolve;

	kernel += kernel5[2 + i] * p_src[col + i * pitch];
	}

	v = (kernel >> 3);
	down_skip_convolve:
	p_dst[col] = v;
	}

	/* now post_proc_across */
	p_src = dst_ptr;
	p_dst = dst_ptr;

	for (i = 0; i < 8; i++)
	d[i] = p_src[i];

	for (col = 0; col < cols; col++) {
	int kernel = 4;
	v = p_src[col];

	d[col & 7] = v;

	for (i = -2; i <= 2; i++) {
	if (abs(v - p_src[col + i]) > flimit)
	goto across_skip_convolve;

	kernel += kernel5[2 + i] * p_src[col + i];
	}

	d[col & 7] = (kernel >> 3);
	across_skip_convolve:

	if (col >= 2)
	p_dst[col - 2] = d[(col - 2) & 7];
	}

	/* handle the last two pixels */
	p_dst[col - 2] = d[(col - 2) & 7];
	p_dst[col - 1] = d[(col - 1) & 7];


	/* next row */
	src_ptr += pitch;
	dst_ptr += pitch;
	}
	}

	static int q2mbl(int x) {
	if (x < 20) x = 20;

	x = 50 + (x - 50) * 10 / 8;
	return x * x / 3;
	}

	void vp9_mbpost_proc_across_ip_c(uint8_t *src, int pitch,
	int rows, int cols, int flimit) {
	int r, c, i;

	uint8_t *s = src;
	uint8_t d[16];


	for (r = 0; r < rows; r++) {
	int sumsq = 0;
	int sum = 0;

	for (i = -8; i <= 6; i++) {
	sumsq += s[i] * s[i];
	sum += s[i];
	d[i + 8] = 0;
	}

	for (c = 0; c < cols + 8; c++) {
	int x = s[c + 7] - s[c - 8];
	int y = s[c + 7] + s[c - 8];

	sum += x;
	sumsq += x * y;

	d[c & 15] = s[c];

	if (sumsq * 15 - sum * sum < flimit) {
	d[c & 15] = (8 + sum + s[c]) >> 4;
	}

	s[c - 8] = d[(c - 8) & 15];
	}

	s += pitch;
	}
	}

	void vp9_mbpost_proc_down_c(uint8_t *dst, int pitch,
	int rows, int cols, int flimit) {
	int r, c, i;
	const short *rv3 = &vp9_rv[63 & rand()]; // NOLINT

	for (c = 0; c < cols; c++) {
	uint8_t *s = &dst[c];
	int sumsq = 0;
	int sum = 0;
	uint8_t d[16];
	const short rv2 = rv3 + ((c 17) & 127);

	for (i = -8; i <= 6; i++) {
	sumsq += s[i * pitch] * s[i * pitch];
	sum += s[i * pitch];
	}

	for (r = 0; r < rows + 8; r++) {
	sumsq += s[7 * pitch] * s[ 7 * pitch] - s[-8 * pitch] * s[-8 * pitch];
	sum += s[7 * pitch] - s[-8 * pitch];
	d[r & 15] = s[0];

	if (sumsq * 15 - sum * sum < flimit) {
	d[r & 15] = (rv2[r & 127] + sum + s[0]) >> 4;
	}

	s[-8 * pitch] = d[(r - 8) & 15];
	s += pitch;
	}
	}
	}

	static void deblock_and_de_macro_block(YV12_BUFFER_CONFIG *source,
	YV12_BUFFER_CONFIG *post,
	int q,
	int low_var_thresh,
	int flag) {
	double level = 6.0e-05 * q * q * q - .0067 * q * q + .306 * q + .0065;
	int ppl = (int)(level + .5);
	(void) low_var_thresh;
	(void) flag;

	vp9_post_proc_down_and_across(source->y_buffer, post->y_buffer,
	source->y_stride, post->y_stride,
	source->y_height, source->y_width, ppl);

	vp9_mbpost_proc_across_ip(post->y_buffer, post->y_stride, post->y_height,
	post->y_width, q2mbl(q));

	vp9_mbpost_proc_down(post->y_buffer, post->y_stride, post->y_height,
	post->y_width, q2mbl(q));

	vp9_post_proc_down_and_across(source->u_buffer, post->u_buffer,
	source->uv_stride, post->uv_stride,
	source->uv_height, source->uv_width, ppl);
	vp9_post_proc_down_and_across(source->v_buffer, post->v_buffer,
	source->uv_stride, post->uv_stride,
	source->uv_height, source->uv_width, ppl);
	}

	void vp9_deblock(const YV12_BUFFER_CONFIG src, YV12_BUFFER_CONFIG dst,
	int q) {
	const int ppl = (int)(6.0e-05 * q * q * q - 0.0067 * q * q + 0.306 * q
	+ 0.0065 + 0.5);
	int i;

	const uint8_t *const srcs[3] = {src->y_buffer, src->u_buffer, src->v_buffer};
	const int src_strides[3] = {src->y_stride, src->uv_stride, src->uv_stride};
	const int src_widths[3] = {src->y_width, src->uv_width, src->uv_width};
	const int src_heights[3] = {src->y_height, src->uv_height, src->uv_height};

	uint8_t *const dsts[3] = {dst->y_buffer, dst->u_buffer, dst->v_buffer};
	const int dst_strides[3] = {dst->y_stride, dst->uv_stride, dst->uv_stride};

	for (i = 0; i < MAX_MB_PLANE; ++i)
	vp9_post_proc_down_and_across(srcs[i], dsts[i],
	src_strides[i], dst_strides[i],
	src_heights[i], src_widths[i], ppl);
	}

	void vp9_denoise(const YV12_BUFFER_CONFIG src, YV12_BUFFER_CONFIG dst,
	int q) {
	const int ppl = (int)(6.0e-05 * q * q * q - 0.0067 * q * q + 0.306 * q
	+ 0.0065 + 0.5);
	int i;

	const uint8_t *const srcs[3] = {src->y_buffer, src->u_buffer, src->v_buffer};
	const int src_strides[3] = {src->y_stride, src->uv_stride, src->uv_stride};
	const int src_widths[3] = {src->y_width, src->uv_width, src->uv_width};
	const int src_heights[3] = {src->y_height, src->uv_height, src->uv_height};

	uint8_t *const dsts[3] = {dst->y_buffer, dst->u_buffer, dst->v_buffer};
	const int dst_strides[3] = {dst->y_stride, dst->uv_stride, dst->uv_stride};

	for (i = 0; i < MAX_MB_PLANE; ++i) {
	const int src_stride = src_strides[i];
	const uint8_t const src = srcs[i] + 2 src_stride + 2;
	const int src_width = src_widths[i] - 4;
	const int src_height = src_heights[i] - 4;

	const int dst_stride = dst_strides[i];
	uint8_t const dst = dsts[i] + 2 dst_stride + 2;

	vp9_post_proc_down_and_across(src, dst, src_stride, dst_stride,
	src_height, src_width, ppl);
	}
	}

	static double gaussian(double sigma, double mu, double x) {
	return 1 / (sigma * sqrt(2.0 * 3.14159265)) *
	(exp(-(x - mu) * (x - mu) / (2 * sigma * sigma)));
	}

	static void fillrd(struct postproc_state *state, int q, int a) {
	char char_dist[300];

	double sigma;
	int ai = a, qi = q, i;

	vp9_clear_system_state();

	sigma = ai + .5 + .6 * (63 - qi) / 63.0;

	/* set up a lookup table of 256 entries that matches
	* a gaussian distribution with sigma determined by q.
	*/
	{
	double i;
	int next, j;

	next = 0;

	for (i = -32; i < 32; i++) {
	int a = (int)(0.5 + 256 * gaussian(sigma, 0, i));

	if (a) {
	for (j = 0; j < a; j++) {
	char_dist[next + j] = (char) i;
	}

	next = next + j;
	}
	}

	for (; next < 256; next++)
	char_dist[next] = 0;
	}

	for (i = 0; i < 3072; i++) {
	state->noise[i] = char_dist[rand() & 0xff]; // NOLINT
	}

	for (i = 0; i < 16; i++) {
	state->blackclamp[i] = -char_dist[0];
	state->whiteclamp[i] = -char_dist[0];
	state->bothclamp[i] = -2 * char_dist[0];
	}

	state->last_q = q;
	state->last_noise = a;
	}

	void vp9_plane_add_noise_c(uint8_t start, char noise,
	char blackclamp[16],
	char whiteclamp[16],
	char bothclamp[16],
	unsigned int width, unsigned int height, int pitch) {
	unsigned int i, j;

	// TODO(jbb): why does simd code use both but c doesn't, normalize and
	// fix..
	(void) bothclamp;
	for (i = 0; i < height; i++) {
	uint8_t pos = start + i pitch;
	char ref = (char )(noise + (rand() & 0xff)); // NOLINT

	for (j = 0; j < width; j++) {
	if (pos[j] < blackclamp[0])
	pos[j] = blackclamp[0];

	if (pos[j] > 255 + whiteclamp[0])
	pos[j] = 255 + whiteclamp[0];

	pos[j] += ref[j];
	}
	}
	}

	int vp9_post_proc_frame(struct VP9Common *cm,
	YV12_BUFFER_CONFIG dest, vp9_ppflags_t ppflags) {
	const int q = MIN(63, cm->lf.filter_level * 10 / 6);
	const int flags = ppflags->post_proc_flag;
	YV12_BUFFER_CONFIG *const ppbuf = &cm->post_proc_buffer;
	struct postproc_state *const ppstate = &cm->postproc_state;

	if (!cm->frame_to_show)
	return -1;

	if (!flags) {
	dest = cm->frame_to_show;
	return 0;
	}

	vp9_clear_system_state();

	#if CONFIG_VP9_POSTPROC \|\| CONFIG_INTERNAL_STATS
	if (vp9_realloc_frame_buffer(&cm->post_proc_buffer, cm->width, cm->height,
	cm->subsampling_x, cm->subsampling_y,
	VP9_DEC_BORDER_IN_PIXELS, NULL, NULL, NULL) < 0)
	vpx_internal_error(&cm->error, VPX_CODEC_MEM_ERROR,
	"Failed to allocate post-processing buffer");
	#endif

	if (flags & VP9D_DEMACROBLOCK) {
	deblock_and_de_macro_block(cm->frame_to_show, ppbuf,
	q + (ppflags->deblocking_level - 5) * 10, 1, 0);
	} else if (flags & VP9D_DEBLOCK) {
	vp9_deblock(cm->frame_to_show, ppbuf, q);
	} else {
	vp8_yv12_copy_frame(cm->frame_to_show, ppbuf);
	}

	if (flags & VP9D_ADDNOISE) {
	const int noise_level = ppflags->noise_level;
	if (ppstate->last_q != q \|\|
	ppstate->last_noise != noise_level) {
	fillrd(ppstate, 63 - q, noise_level);
	}

	vp9_plane_add_noise(ppbuf->y_buffer, ppstate->noise, ppstate->blackclamp,
	ppstate->whiteclamp, ppstate->bothclamp,
	ppbuf->y_width, ppbuf->y_height, ppbuf->y_stride);
	}

	dest = ppbuf;

	/* handle problem with extending borders */
	dest->y_width = cm->width;
	dest->y_height = cm->height;
	dest->uv_width = dest->y_width >> cm->subsampling_x;
	dest->uv_height = dest->y_height >> cm->subsampling_y;

	return 0;
	}
	#endif