text: /*
   * Copyright (c) 2003 Daniel Moreno <comac AT comac DOT darktech DOT org>
   * Copyright (c) 2010 Baptiste Coudurier
   *
   * This file is part of FFmpeg, ported from MPlayer.
   *
   * FFmpeg is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   *
   * FFmpeg is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License along
   * with FFmpeg; if not, write to the Free Software Foundation, Inc.,
   * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
   */
  
  /**
   * @file
   * high quality 3d video denoiser, ported from MPlayer
   * libmpcodecs/vf_hqdn3d.c.
   */
  
  #include "libavutil/pixdesc.h"
  #include "avfilter.h"
  
  typedef struct {
      int Coefs[4][512*16];
      unsigned int *Line;
      unsigned short *Frame[3];
      int hsub, vsub;
  } HQDN3DContext;
  
  static inline unsigned int LowPassMul(unsigned int PrevMul, unsigned int CurrMul, int *Coef)
  {
      //    int dMul= (PrevMul&0xFFFFFF)-(CurrMul&0xFFFFFF);
      int dMul= PrevMul-CurrMul;
      unsigned int d=((dMul+0x10007FF)>>12);
      return CurrMul + Coef[d];
  }
  
  static void deNoiseTemporal(unsigned char *FrameSrc,
                              unsigned char *FrameDest,
                              unsigned short *FrameAnt,
                              int W, int H, int sStride, int dStride,
                              int *Temporal)
  {
      long X, Y;
      unsigned int PixelDst;
  
      for (Y = 0; Y < H; Y++) {
          for (X = 0; X < W; X++) {
              PixelDst = LowPassMul(FrameAnt[X]<<8, FrameSrc[X]<<16, Temporal);
              FrameAnt[X] = ((PixelDst+0x1000007F)>>8);
              FrameDest[X]= ((PixelDst+0x10007FFF)>>16);
          }
          FrameSrc  += sStride;
          FrameDest += dStride;
          FrameAnt += W;
      }
  }
  
  static void deNoiseSpacial(unsigned char *Frame,
                             unsigned char *FrameDest,
                             unsigned int *LineAnt,
                             int W, int H, int sStride, int dStride,
                             int *Horizontal, int *Vertical)
  {
      long X, Y;
      long sLineOffs = 0, dLineOffs = 0;
      unsigned int PixelAnt;
      unsigned int PixelDst;
  
      /* First pixel has no left nor top neighbor. */
      PixelDst = LineAnt[0] = PixelAnt = Frame[0]<<16;
      FrameDest[0]= ((PixelDst+0x10007FFF)>>16);
  
      /* First line has no top neighbor, only left. */
      for (X = 1; X < W; X++) {
          PixelDst = LineAnt[X] = LowPassMul(PixelAnt, Frame[X]<<16, Horizontal);
          FrameDest[X]= ((PixelDst+0x10007FFF)>>16);
      }
  
      for (Y = 1; Y < H; Y++) {
          unsigned int PixelAnt;
          sLineOffs += sStride, dLineOffs += dStride;
          /* First pixel on each line doesn't have previous pixel */
          PixelAnt = Frame[sLineOffs]<<16;
          PixelDst = LineAnt[0] = LowPassMul(LineAnt[0], PixelAnt, Vertical);
          FrameDest[dLineOffs]= ((PixelDst+0x10007FFF)>>16);
  
          for (X = 1; X < W; X++) {
              unsigned int PixelDst;
              /* The rest are normal */
              PixelAnt = LowPassMul(PixelAnt, Frame[sLineOffs+X]<<16, Horizontal);
              PixelDst = LineAnt[X] = LowPassMul(LineAnt[X], PixelAnt, Vertical);
              FrameDest[dLineOffs+X]= ((PixelDst+0x10007FFF)>>16);
          }
      }
  }
  
  static void deNoise(unsigned char *Frame,
                      unsigned char *FrameDest,
                      unsigned int *LineAnt,
                      unsigned short **FrameAntPtr,
                      int W, int H, int sStride, int dStride,
                      int *Horizontal, int *Vertical, int *Temporal)
  {
      long X, Y;
      long sLineOffs = 0, dLineOffs = 0;
      unsigned int PixelAnt;
      unsigned int PixelDst;
      unsigned short* FrameAnt=(*FrameAntPtr);
  
      if (!FrameAnt) {
          (*FrameAntPtr) = FrameAnt = av_malloc(W*H*sizeof(unsigned short));
          for (Y = 0; Y < H; Y++) {
              unsigned short* dst=&FrameAnt[Y*W];
              unsigned char* src=Frame+Y*sStride;
              for (X = 0; X < W; X++) dst[X]=src[X]<<8;
          }
      }
  
      if (!Horizontal[0] && !Vertical[0]) {
          deNoiseTemporal(Frame, FrameDest, FrameAnt,
                          W, H, sStride, dStride, Temporal);
          return;
      }
      if (!Temporal[0]) {
          deNoiseSpacial(Frame, FrameDest, LineAnt,
                         W, H, sStride, dStride, Horizontal, Vertical);
          return;
      }
  
      /* First pixel has no left nor top neighbor. Only previous frame */
      LineAnt[0] = PixelAnt = Frame[0]<<16;
      PixelDst = LowPassMul(FrameAnt[0]<<8, PixelAnt, Temporal);
      FrameAnt[0] = ((PixelDst+0x1000007F)>>8);
      FrameDest[0]= ((PixelDst+0x10007FFF)>>16);
  
      /* First line has no top neighbor. Only left one for each pixel and
       * last frame */
      for (X = 1; X < W; X++) {
          LineAnt[X] = PixelAnt = LowPassMul(PixelAnt, Frame[X]<<16, Horizontal);
          PixelDst = LowPassMul(FrameAnt[X]<<8, PixelAnt, Temporal);
          FrameAnt[X] = ((PixelDst+0x1000007F)>>8);
          FrameDest[X]= ((PixelDst+0x10007FFF)>>16);
      }
  
      for (Y = 1; Y < H; Y++) {
          unsigned int PixelAnt;
          unsigned short* LinePrev=&FrameAnt[Y*W];
          sLineOffs += sStride, dLineOffs += dStride;
          /* First pixel on each line doesn't have previous pixel */
          PixelAnt = Frame[sLineOffs]<<16;
          LineAnt[0] = LowPassMul(LineAnt[0], PixelAnt, Vertical);
          PixelDst = LowPassMul(LinePrev[0]<<8, LineAnt[0], Temporal);
          LinePrev[0] = ((PixelDst+0x1000007F)>>8);
          FrameDest[dLineOffs]= ((PixelDst+0x10007FFF)>>16);
  
          for (X = 1; X < W; X++) {
              unsigned int PixelDst;
              /* The rest are normal */
              PixelAnt = LowPassMul(PixelAnt, Frame[sLineOffs+X]<<16, Horizontal);
              LineAnt[X] = LowPassMul(LineAnt[X], PixelAnt, Vertical);
              PixelDst = LowPassMul(LinePrev[X]<<8, LineAnt[X], Temporal);
              LinePrev[X] = ((PixelDst+0x1000007F)>>8);
              FrameDest[dLineOffs+X]= ((PixelDst+0x10007FFF)>>16);
          }
      }
  }
  
  static void PrecalcCoefs(int *Ct, double Dist25)
  {
      int i;
      double Gamma, Simil, C;
  
      Gamma = log(0.25) / log(1.0 - Dist25/255.0 - 0.00001);
  
      for (i = -255*16; i <= 255*16; i++) {
          Simil = 1.0 - FFABS(i) / (16*255.0);
          C = pow(Simil, Gamma) * 65536.0 * i / 16.0;
          Ct[16*256+i] = lrint(C);
      }
  
      Ct[0] = !!Dist25;
  }
  
  #define PARAM1_DEFAULT 4.0
  #define PARAM2_DEFAULT 3.0
  #define PARAM3_DEFAULT 6.0
  
  static int init(AVFilterContext *ctx, const char *args, void *opaque)
  {
      HQDN3DContext *hqdn3d = ctx->priv;
      double LumSpac, LumTmp, ChromSpac, ChromTmp;
      double Param1, Param2, Param3, Param4;
  
      LumSpac   = PARAM1_DEFAULT;
      ChromSpac = PARAM2_DEFAULT;
      LumTmp    = PARAM3_DEFAULT;
      ChromTmp  = LumTmp * ChromSpac / LumSpac;
  
      if (args) {
          switch (sscanf(args, "%lf:%lf:%lf:%lf",
                         &Param1, &Param2, &Param3, &Param4)) {
          case 1:
              LumSpac   = Param1;
              ChromSpac = PARAM2_DEFAULT * Param1 / PARAM1_DEFAULT;
              LumTmp    = PARAM3_DEFAULT * Param1 / PARAM1_DEFAULT;
              ChromTmp  = LumTmp * ChromSpac / LumSpac;
              break;
          case 2:
              LumSpac   = Param1;
              ChromSpac = Param2;
              LumTmp    = PARAM3_DEFAULT * Param1 / PARAM1_DEFAULT;
              ChromTmp  = LumTmp * ChromSpac / LumSpac;
              break;
          case 3:
              LumSpac   = Param1;
              ChromSpac = Param2;
              LumTmp    = Param3;
              ChromTmp  = LumTmp * ChromSpac / LumSpac;
              break;
          case 4:
              LumSpac   = Param1;
              ChromSpac = Param2;
              LumTmp    = Param3;
              ChromTmp  = Param4;
              break;
          }
      }
  
      av_log(ctx, AV_LOG_INFO, "ls:%lf cs:%lf lt:%lf ct:%lf\n",
             LumSpac, ChromSpac, LumTmp, ChromTmp);
      if (LumSpac < 0 || ChromSpac < 0 || isnan(ChromTmp)) {
          av_log(ctx, AV_LOG_ERROR,
                 "Invalid negative value for luma or chroma spatial strength, "
                 "or resulting value for chroma temporal strength is nan.\n");
          return AVERROR(EINVAL);
      }
  
      PrecalcCoefs(hqdn3d->Coefs[0], LumSpac);
      PrecalcCoefs(hqdn3d->Coefs[1], LumTmp);
      PrecalcCoefs(hqdn3d->Coefs[2], ChromSpac);
      PrecalcCoefs(hqdn3d->Coefs[3], ChromTmp);
  
      return 0;
  }
  
  static void uninit(AVFilterContext *ctx)
  {
      HQDN3DContext *hqdn3d = ctx->priv;
  
      av_freep(&hqdn3d->Line);
      av_freep(&hqdn3d->Frame[0]);
      av_freep(&hqdn3d->Frame[1]);
      av_freep(&hqdn3d->Frame[2]);
  }
  
  static int query_formats(AVFilterContext *ctx)
  {
      static const enum PixelFormat pix_fmts[] = {
          PIX_FMT_YUV420P, PIX_FMT_YUV422P, PIX_FMT_YUV411P, PIX_FMT_NONE
      };
  
      avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts));
  
      return 0;
  }
  
  static int config_input(AVFilterLink *inlink)
  {
      HQDN3DContext *hqdn3d = inlink->dst->priv;
  
      hqdn3d->hsub = av_pix_fmt_descriptors[inlink->format].log2_chroma_w;
      hqdn3d->vsub = av_pix_fmt_descriptors[inlink->format].log2_chroma_h;
  
      hqdn3d->Line = av_malloc(inlink->w * sizeof(*hqdn3d->Line));
      if (!hqdn3d->Line)
          return AVERROR(ENOMEM);
  
      return 0;
  }
  
  static void null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir) { }
  
  static void end_frame(AVFilterLink *inlink)
  {
      HQDN3DContext *hqdn3d = inlink->dst->priv;
      AVFilterLink *outlink = inlink->dst->outputs[0];
      AVFilterBufferRef *inpic  = inlink ->cur_buf;
      AVFilterBufferRef *outpic = outlink->out_buf;
      int cw = inpic->video->w >> hqdn3d->hsub;
      int ch = inpic->video->h >> hqdn3d->vsub;
  
      deNoise(inpic->data[0], outpic->data[0],
              hqdn3d->Line, &hqdn3d->Frame[0], inpic->video->w, inpic->video->h,
              inpic->linesize[0], outpic->linesize[0],
              hqdn3d->Coefs[0],
              hqdn3d->Coefs[0],
              hqdn3d->Coefs[1]);
      deNoise(inpic->data[1], outpic->data[1],
              hqdn3d->Line, &hqdn3d->Frame[1], cw, ch,
              inpic->linesize[1], outpic->linesize[1],
              hqdn3d->Coefs[2],
              hqdn3d->Coefs[2],
              hqdn3d->Coefs[3]);
      deNoise(inpic->data[2], outpic->data[2],
              hqdn3d->Line, &hqdn3d->Frame[2], cw, ch,
              inpic->linesize[2], outpic->linesize[2],
              hqdn3d->Coefs[2],
              hqdn3d->Coefs[2],
              hqdn3d->Coefs[3]);
  
      avfilter_draw_slice(outlink, 0, inpic->video->h, 1);
      avfilter_end_frame(outlink);
      avfilter_unref_buffer(inpic);
      avfilter_unref_buffer(outpic);
  }
  
  AVFilter avfilter_vf_hqdn3d = {
      .name          = "hqdn3d",
      .description   = NULL_IF_CONFIG_SMALL("Apply a High Quality 3D Denoiser."),
  
      .priv_size     = sizeof(HQDN3DContext),
      .init          = init,
      .uninit        = uninit,
      .query_formats = query_formats,
  
      .inputs    = (const AVFilterPad[]) {{ .name       = "default",
                                      .type             = AVMEDIA_TYPE_VIDEO,
                                      .draw_slice       = null_draw_slice,
                                      .config_props     = config_input,
                                      .end_frame        = end_frame },
                                    { .name = NULL}},
  
      .outputs   = (const AVFilterPad[]) {{ .name       = "default",
                                      .type             = AVMEDIA_TYPE_VIDEO },
                                    { .name = NULL}},
  };
  