text: /*
   * Copyright (C) 2006-2011 Michael Niedermayer <michaelni@gmx.at>
   *               2010      James Darnley <james.darnley@gmail.com>
   *
   * 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.
   */
  
  #include "libavutil/avassert.h"
  #include "libavutil/cpu.h"
  #include "libavutil/common.h"
  #include "libavutil/opt.h"
  #include "libavutil/pixdesc.h"
  #include "avfilter.h"
  #include "formats.h"
  #include "internal.h"
  #include "video.h"
  #include "yadif.h"
  
  #undef NDEBUG
  #include <assert.h>
  
  #define PERM_RWP AV_PERM_WRITE | AV_PERM_PRESERVE | AV_PERM_REUSE
  
  #define CHECK(j)\
      {   int score = FFABS(cur[mrefs + off_left + (j)] - cur[prefs + off_left - (j)])\
                    + FFABS(cur[mrefs  +(j)] - cur[prefs  -(j)])\
                    + FFABS(cur[mrefs + off_right + (j)] - cur[prefs + off_right - (j)]);\
          if (score < spatial_score) {\
              spatial_score= score;\
              spatial_pred= (cur[mrefs  +(j)] + cur[prefs  -(j)])>>1;\
  
  #define FILTER(start, end) \
      for (x = start;  x < end; x++) { \
          int c = cur[mrefs]; \
          int d = (prev2[0] + next2[0])>>1; \
          int e = cur[prefs]; \
          int temporal_diff0 = FFABS(prev2[0] - next2[0]); \
          int temporal_diff1 =(FFABS(prev[mrefs] - c) + FFABS(prev[prefs] - e) )>>1; \
          int temporal_diff2 =(FFABS(next[mrefs] - c) + FFABS(next[prefs] - e) )>>1; \
          int diff = FFMAX3(temporal_diff0 >> 1, temporal_diff1, temporal_diff2); \
          int spatial_pred = (c+e) >> 1; \
          int off_right = (x < w - 1) ? 1 : -1;\
          int off_left  = x ? -1 : 1;\
          int spatial_score = FFABS(cur[mrefs + off_left]  - cur[prefs + off_left]) + FFABS(c-e) \
                            + FFABS(cur[mrefs + off_right] - cur[prefs + off_right]) - 1; \
   \
          if (x > 2 && x < w - 3) {\
              CHECK(-1) CHECK(-2) }} }} \
              CHECK( 1) CHECK( 2) }} }} \
          }\
   \
          if (mode < 2) { \
              int b = (prev2[2 * mrefs] + next2[2 * mrefs])>>1; \
              int f = (prev2[2 * prefs] + next2[2 * prefs])>>1; \
              int max = FFMAX3(d - e, d - c, FFMIN(b - c, f - e)); \
              int min = FFMIN3(d - e, d - c, FFMAX(b - c, f - e)); \
   \
              diff = FFMAX3(diff, min, -max); \
          } \
   \
          if (spatial_pred > d + diff) \
             spatial_pred = d + diff; \
          else if (spatial_pred < d - diff) \
             spatial_pred = d - diff; \
   \
          dst[0] = spatial_pred; \
   \
          dst++; \
          cur++; \
          prev++; \
          next++; \
          prev2++; \
          next2++; \
      }
  
  static void filter_line_c(void *dst1,
                            void *prev1, void *cur1, void *next1,
                            int w, int prefs, int mrefs, int parity, int mode)
  {
      uint8_t *dst  = dst1;
      uint8_t *prev = prev1;
      uint8_t *cur  = cur1;
      uint8_t *next = next1;
      int x;
      uint8_t *prev2 = parity ? prev : cur ;
      uint8_t *next2 = parity ? cur  : next;
  
      FILTER(0, w)
  }
  
  static void filter_edges(void *dst1, void *prev1, void *cur1, void *next1,
                           int w, int prefs, int mrefs, int parity, int mode,
                           int l_edge)
  {
      uint8_t *dst  = dst1;
      uint8_t *prev = prev1;
      uint8_t *cur  = cur1;
      uint8_t *next = next1;
      int x;
      uint8_t *prev2 = parity ? prev : cur ;
      uint8_t *next2 = parity ? cur  : next;
  
      FILTER(0, l_edge)
  
      dst  = (uint8_t*)dst1  + w - 3;
      prev = (uint8_t*)prev1 + w - 3;
      cur  = (uint8_t*)cur1  + w - 3;
      next = (uint8_t*)next1 + w - 3;
      prev2 = (uint8_t*)(parity ? prev : cur);
      next2 = (uint8_t*)(parity ? cur  : next);
  
      FILTER(w - 3, w)
  }
  
  
  static void filter_line_c_16bit(void *dst1,
                                  void *prev1, void *cur1, void *next1,
                                  int w, int prefs, int mrefs, int parity,
                                  int mode)
  {
      uint16_t *dst  = dst1;
      uint16_t *prev = prev1;
      uint16_t *cur  = cur1;
      uint16_t *next = next1;
      int x;
      uint16_t *prev2 = parity ? prev : cur ;
      uint16_t *next2 = parity ? cur  : next;
      mrefs /= 2;
      prefs /= 2;
  
      FILTER(0, w)
  }
  
  static void filter_edges_16bit(void *dst1, void *prev1, void *cur1, void *next1,
                                 int w, int prefs, int mrefs, int parity, int mode,
                                 int l_edge)
  {
      uint16_t *dst  = dst1;
      uint16_t *prev = prev1;
      uint16_t *cur  = cur1;
      uint16_t *next = next1;
      int x;
      uint16_t *prev2 = parity ? prev : cur ;
      uint16_t *next2 = parity ? cur  : next;
  
      FILTER(0, l_edge)
  
      dst   = (uint16_t*)dst1  + w - 3;
      prev  = (uint16_t*)prev1 + w - 3;
      cur   = (uint16_t*)cur1  + w - 3;
      next  = (uint16_t*)next1 + w - 3;
      prev2 = (uint16_t*)(parity ? prev : cur);
      next2 = (uint16_t*)(parity ? cur  : next);
  
      FILTER(w - 3, w)
  }
  
  static void filter(AVFilterContext *ctx, AVFilterBufferRef *dstpic,
                     int parity, int tff)
  {
      YADIFContext *yadif = ctx->priv;
      int y, i;
  
      for (i = 0; i < yadif->csp->nb_components; i++) {
          int w = dstpic->video->w;
          int h = dstpic->video->h;
          int refs = yadif->cur->linesize[i];
          int df = (yadif->csp->comp[i].depth_minus1 + 8) / 8;
          int l_edge, l_edge_pix;
  
          if (i == 1 || i == 2) {
          /* Why is this not part of the per-plane description thing? */
              w >>= yadif->csp->log2_chroma_w;
              h >>= yadif->csp->log2_chroma_h;
          }
  
          /* filtering reads 3 pixels to the left/right; to avoid invalid reads,
           * we need to call the c variant which avoids this for border pixels
           */
          l_edge     = yadif->req_align;
          l_edge_pix = l_edge / df;
  
          for (y = 0; y < h; y++) {
              if ((y ^ parity) & 1) {
                  uint8_t *prev = &yadif->prev->data[i][y * refs];
                  uint8_t *cur  = &yadif->cur ->data[i][y * refs];
                  uint8_t *next = &yadif->next->data[i][y * refs];
                  uint8_t *dst  = &dstpic->data[i][y * dstpic->linesize[i]];
                  int     mode  = y == 1 || y + 2 == h ? 2 : yadif->mode;
                  if (yadif->req_align) {
                      yadif->filter_line(dst + l_edge, prev + l_edge, cur + l_edge,
                                         next + l_edge, w - l_edge_pix - 3,
                                         y + 1 < h ? refs : -refs,
                                         y ? -refs : refs,
                                         parity ^ tff, mode);
                      yadif->filter_edges(dst, prev, cur, next, w,
                                           y + 1 < h ? refs : -refs,
                                           y ? -refs : refs,
                                           parity ^ tff, mode, l_edge_pix);
                  } else {
                      yadif->filter_line(dst, prev, cur, next + l_edge, w,
                                         y + 1 < h ? refs : -refs,
                                         y ? -refs : refs,
                                         parity ^ tff, mode);
                  }
              } else {
                  memcpy(&dstpic->data[i][y * dstpic->linesize[i]],
                         &yadif->cur->data[i][y * refs], w * df);
              }
          }
      }
  
      emms_c();
  }
  
  static int return_frame(AVFilterContext *ctx, int is_second)
  {
      YADIFContext *yadif = ctx->priv;
      AVFilterLink *link  = ctx->outputs[0];
      int tff, ret;
  
      if (yadif->parity == -1) {
          tff = yadif->cur->video->interlaced ?
                yadif->cur->video->top_field_first : 1;
      } else {
          tff = yadif->parity ^ 1;
      }
  
      if (is_second) {
          yadif->out = ff_get_video_buffer(link, PERM_RWP, link->w, link->h);
          if (!yadif->out)
              return AVERROR(ENOMEM);
  
          avfilter_copy_buffer_ref_props(yadif->out, yadif->cur);
          yadif->out->video->interlaced = 0;
      }
  
      filter(ctx, yadif->out, tff ^ !is_second, tff);
  
      if (is_second) {
          int64_t cur_pts  = yadif->cur->pts;
          int64_t next_pts = yadif->next->pts;
  
          if (next_pts != AV_NOPTS_VALUE && cur_pts != AV_NOPTS_VALUE) {
              yadif->out->pts = cur_pts + next_pts;
          } else {
              yadif->out->pts = AV_NOPTS_VALUE;
          }
      }
      ret = ff_filter_frame(ctx->outputs[0], yadif->out);
  
      yadif->frame_pending = (yadif->mode&1) && !is_second;
      return ret;
  }
  
  static int filter_frame(AVFilterLink *link, AVFilterBufferRef *picref)
  {
      AVFilterContext *ctx = link->dst;
      YADIFContext *yadif = ctx->priv;
  
      av_assert0(picref);
  
      if (yadif->frame_pending)
          return_frame(ctx, 1);
  
      if (yadif->prev)
          avfilter_unref_buffer(yadif->prev);
      yadif->prev = yadif->cur;
      yadif->cur  = yadif->next;
      yadif->next = picref;
  
      if (!yadif->cur)
          return 0;
  
      if (yadif->deint && !yadif->cur->video->interlaced) {
          yadif->out  = avfilter_ref_buffer(yadif->cur, ~AV_PERM_WRITE);
          if (!yadif->out)
              return AVERROR(ENOMEM);
  
          avfilter_unref_bufferp(&yadif->prev);
          if (yadif->out->pts != AV_NOPTS_VALUE)
              yadif->out->pts *= 2;
          return ff_filter_frame(ctx->outputs[0], yadif->out);
      }
  
      if (!yadif->prev &&
          !(yadif->prev = avfilter_ref_buffer(yadif->cur, ~AV_PERM_WRITE)))
          return AVERROR(ENOMEM);
  
      yadif->out = ff_get_video_buffer(ctx->outputs[0], PERM_RWP,
                                       link->w, link->h);
      if (!yadif->out)
          return AVERROR(ENOMEM);
  
      avfilter_copy_buffer_ref_props(yadif->out, yadif->cur);
      yadif->out->video->interlaced = 0;
  
      if (yadif->out->pts != AV_NOPTS_VALUE)
          yadif->out->pts *= 2;
  
      return return_frame(ctx, 0);
  }
  
  static int request_frame(AVFilterLink *link)
  {
      AVFilterContext *ctx = link->src;
      YADIFContext *yadif = ctx->priv;
  
      if (yadif->frame_pending) {
          return_frame(ctx, 1);
          return 0;
      }
  
      do {
          int ret;
  
          if (yadif->eof)
              return AVERROR_EOF;
  
          ret  = ff_request_frame(link->src->inputs[0]);
  
          if (ret == AVERROR_EOF && yadif->cur) {
              AVFilterBufferRef *next = avfilter_ref_buffer(yadif->next, ~AV_PERM_WRITE);
  
              if (!next)
                  return AVERROR(ENOMEM);
  
              next->pts = yadif->next->pts * 2 - yadif->cur->pts;
  
              filter_frame(link->src->inputs[0], next);
              yadif->eof = 1;
          } else if (ret < 0) {
              return ret;
          }
      } while (!yadif->cur);
  
      return 0;
  }
  
  #define OFFSET(x) offsetof(YADIFContext, x)
  #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
  
  #define CONST(name, help, val, unit) { name, help, 0, AV_OPT_TYPE_CONST, {.i64=val}, INT_MIN, INT_MAX, FLAGS, unit }
  
  static const AVOption yadif_options[] = {
      { "mode",   "specify the interlacing mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64=YADIF_MODE_SEND_FRAME}, 0, 3, FLAGS, "mode"},
      CONST("send_frame",           "send one frame for each frame",                                     YADIF_MODE_SEND_FRAME,           "mode"),
      CONST("send_field",           "send one frame for each field",                                     YADIF_MODE_SEND_FIELD,           "mode"),
      CONST("send_frame_nospatial", "send one frame for each frame, but skip spatial interlacing check", YADIF_MODE_SEND_FRAME_NOSPATIAL, "mode"),
      CONST("send_field_nospatial", "send one frame for each field, but skip spatial interlacing check", YADIF_MODE_SEND_FIELD_NOSPATIAL, "mode"),
  
      { "parity", "specify the assumed picture field parity", OFFSET(parity), AV_OPT_TYPE_INT, {.i64=YADIF_PARITY_AUTO}, -1, 1, FLAGS, "parity" },
      CONST("tff",  "assume top field first",    YADIF_PARITY_TFF,  "parity"),
      CONST("bff",  "assume bottom field first", YADIF_PARITY_BFF,  "parity"),
      CONST("auto", "auto detect parity",        YADIF_PARITY_AUTO, "parity"),
  
      { "deint", "specify which frames to deinterlace", OFFSET(deint), AV_OPT_TYPE_INT, {.i64=YADIF_DEINT_ALL}, 0, 1, FLAGS, "deint" },
      CONST("all",        "deinterlace all frames",                       YADIF_DEINT_ALL,         "deint"),
      CONST("interlaced", "only deinterlace frames marked as interlaced", YADIF_DEINT_INTERLACED,  "deint"),
  
      {NULL},
  };
  
  AVFILTER_DEFINE_CLASS(yadif);
  
  static av_cold void uninit(AVFilterContext *ctx)
  {
      YADIFContext *yadif = ctx->priv;
  
      avfilter_unref_bufferp(&yadif->prev);
      avfilter_unref_bufferp(&yadif->cur );
      avfilter_unref_bufferp(&yadif->next);
      av_opt_free(yadif);
  }
  
  static int query_formats(AVFilterContext *ctx)
  {
      static const enum AVPixelFormat pix_fmts[] = {
          AV_PIX_FMT_YUV420P,
          AV_PIX_FMT_YUV422P,
          AV_PIX_FMT_YUV444P,
          AV_PIX_FMT_YUV410P,
          AV_PIX_FMT_YUV411P,
          AV_PIX_FMT_GRAY8,
          AV_PIX_FMT_YUVJ420P,
          AV_PIX_FMT_YUVJ422P,
          AV_PIX_FMT_YUVJ444P,
          AV_NE( AV_PIX_FMT_GRAY16BE, AV_PIX_FMT_GRAY16LE ),
          AV_PIX_FMT_YUV440P,
          AV_PIX_FMT_YUVJ440P,
          AV_NE( AV_PIX_FMT_YUV420P9BE,  AV_PIX_FMT_YUV420P9LE ),
          AV_NE( AV_PIX_FMT_YUV422P9BE,  AV_PIX_FMT_YUV422P9LE ),
          AV_NE( AV_PIX_FMT_YUV444P9BE,  AV_PIX_FMT_YUV444P9LE ),
          AV_NE( AV_PIX_FMT_YUV420P10BE, AV_PIX_FMT_YUV420P10LE ),
          AV_NE( AV_PIX_FMT_YUV422P10BE, AV_PIX_FMT_YUV422P10LE ),
          AV_NE( AV_PIX_FMT_YUV444P10BE, AV_PIX_FMT_YUV444P10LE ),
          AV_NE( AV_PIX_FMT_YUV420P12BE, AV_PIX_FMT_YUV420P12LE ),
          AV_NE( AV_PIX_FMT_YUV422P12BE, AV_PIX_FMT_YUV422P12LE ),
          AV_NE( AV_PIX_FMT_YUV444P12BE, AV_PIX_FMT_YUV444P12LE ),
          AV_NE( AV_PIX_FMT_YUV420P14BE, AV_PIX_FMT_YUV420P14LE ),
          AV_NE( AV_PIX_FMT_YUV422P14BE, AV_PIX_FMT_YUV422P14LE ),
          AV_NE( AV_PIX_FMT_YUV444P14BE, AV_PIX_FMT_YUV444P14LE ),
          AV_NE( AV_PIX_FMT_YUV420P16BE, AV_PIX_FMT_YUV420P16LE ),
          AV_NE( AV_PIX_FMT_YUV422P16BE, AV_PIX_FMT_YUV422P16LE ),
          AV_NE( AV_PIX_FMT_YUV444P16BE, AV_PIX_FMT_YUV444P16LE ),
          AV_PIX_FMT_YUVA420P,
          AV_PIX_FMT_YUVA422P,
          AV_PIX_FMT_YUVA444P,
          AV_PIX_FMT_NONE
      };
  
      ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
  
      return 0;
  }
  
  static av_cold int init(AVFilterContext *ctx, const char *args)
  {
      YADIFContext *yadif = ctx->priv;
      static const char *shorthand[] = { "mode", "parity", "deint", NULL };
      int ret;
  
      yadif->class = &yadif_class;
      av_opt_set_defaults(yadif);
  
      if ((ret = av_opt_set_from_string(yadif, args, shorthand, "=", ":")) < 0)
          return ret;
  
      av_log(ctx, AV_LOG_VERBOSE, "mode:%d parity:%d deint:%d\n",
             yadif->mode, yadif->parity, yadif->deint);
  
      return 0;
  }
  
  static int config_props(AVFilterLink *link)
  {
      AVFilterContext *ctx = link->src;
      YADIFContext *s = link->src->priv;
  
      link->time_base.num = link->src->inputs[0]->time_base.num;
      link->time_base.den = link->src->inputs[0]->time_base.den * 2;
      link->w             = link->src->inputs[0]->w;
      link->h             = link->src->inputs[0]->h;
  
      if(s->mode&1)
          link->frame_rate = av_mul_q(link->src->inputs[0]->frame_rate, (AVRational){2,1});
  
      if (link->w < 3 || link->h < 3) {
          av_log(ctx, AV_LOG_ERROR, "Video of less than 3 columns or lines is not supported\n");
          return AVERROR(EINVAL);
      }
  
      s->csp = av_pix_fmt_desc_get(link->format);
      if (s->csp->comp[0].depth_minus1 / 8 == 1) {
          s->filter_line  = filter_line_c_16bit;
          s->filter_edges = filter_edges_16bit;
      } else {
          s->filter_line  = filter_line_c;
          s->filter_edges = filter_edges;
  
          if (ARCH_X86)
              ff_yadif_init_x86(s);
      }
  
      return 0;
  }
  
  static const AVFilterPad avfilter_vf_yadif_inputs[] = {
      {
          .name             = "default",
          .type             = AVMEDIA_TYPE_VIDEO,
          .filter_frame     = filter_frame,
          .min_perms        = AV_PERM_PRESERVE,
      },
      { NULL }
  };
  
  static const AVFilterPad avfilter_vf_yadif_outputs[] = {
      {
          .name          = "default",
          .type          = AVMEDIA_TYPE_VIDEO,
          .request_frame = request_frame,
          .config_props  = config_props,
      },
      { NULL }
  };
  
  AVFilter avfilter_vf_yadif = {
      .name          = "yadif",
      .description   = NULL_IF_CONFIG_SMALL("Deinterlace the input image."),
  
      .priv_size     = sizeof(YADIFContext),
      .init          = init,
      .uninit        = uninit,
      .query_formats = query_formats,
  
      .inputs    = avfilter_vf_yadif_inputs,
      .outputs   = avfilter_vf_yadif_outputs,
  
      .priv_class = &yadif_class,
  };
  