libavfilter/libmpcodecs/vf_remove_logo.c

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/*
 * This filter loads a .pgm mask file showing where a logo is and uses
 * a blur transform to remove the logo.
 *
 * Copyright (C) 2005 Robert Edele <yartrebo@earthlink.net>
 *
 * This file is part of MPlayer.
 *
 * MPlayer 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.
 *
 * MPlayer 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 MPlayer; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <inttypes.h>

#include "config.h"
#include "mp_msg.h"
#include "libvo/fastmemcpy.h"

#include "img_format.h"
#include "mp_image.h"
#include "vf.h"

//===========================================================================//

#define max(x,y) ((x)>(y)?(x):(y))

#define min(x,y) ((x)>(y)?(y):(x))

#define test_filter(image, x, y) ((unsigned char) (image->pixel[((y) * image->width) + (x)]))

#define apply_mask_fudge_factor(x) (((x) >> 2) + x)

typedef struct
{
  unsigned int width;
  unsigned int height;

  unsigned char * pixel;

} pgm_structure;

struct vf_priv_s
{
  unsigned int fmt; /* Not exactly sure of the use for this. It came with the example filter I used as a basis for this, and it looks like a lot of stuff will break if I remove it. */
  int max_mask_size; /* The largest possible mask size that will be needed with the given filter and corresponding half_size_filter. The half_size_filter can have a larger requirment in some rare (but not degenerate) cases. */
  int * * * mask; /* Stores our collection of masks. The first * is for an array of masks, the second for the y axis, and the third for the x axis. */
  pgm_structure * filter; /* Stores the full-size filter image. This is used to tell what pixels are in the logo or not in the luma plane. */
  pgm_structure * half_size_filter; /* Stores a 50% width and 50% height filter image. This is used to tell what pixels are in the logo or not in the chroma planes. */
  /* These 8 variables store the bounding rectangles that the logo resides in. */
  int bounding_rectangle_posx1;
  int bounding_rectangle_posy1;
  int bounding_rectangle_posx2;
  int bounding_rectangle_posy2;
  int bounding_rectangle_half_size_posx1;
  int bounding_rectangle_half_size_posy1;
  int bounding_rectangle_half_size_posx2;
  int bounding_rectangle_half_size_posy2;
} vf_priv_s;

static void * safe_malloc(int size)
{
  void * answer = malloc(size);
  if (answer == NULL)
    mp_msg(MSGT_VFILTER, MSGL_ERR, "Unable to allocate memory in vf_remove_logo.c\n");

  return answer;
}

static void calculate_bounding_rectangle(int * posx1, int * posy1, int * posx2, int * posy2, pgm_structure * filter)
{
  int x; /* Temporary variables to run  */
  int y; /* through each row or column. */
  int start_x;
  int start_y;
  int end_x = filter->width - 1;
  int end_y = filter->height - 1;
  int did_we_find_a_logo_pixel = 0;

  /* Let's find the top bound first. */
  for (start_x = 0; start_x < filter->width && !did_we_find_a_logo_pixel; start_x++)
  {
    for (y = 0; y < filter->height; y++)
    {
      did_we_find_a_logo_pixel |= test_filter(filter, start_x, y);
    }
  }
  start_x--;

  /* Now the bottom bound. */
  did_we_find_a_logo_pixel = 0;
  for (end_x = filter->width - 1; end_x > start_x && !did_we_find_a_logo_pixel; end_x--)
  {
    for (y = 0; y < filter->height; y++)
    {
      did_we_find_a_logo_pixel |= test_filter(filter, end_x, y);
    }
  }
  end_x++;

  /* Left bound. */
  did_we_find_a_logo_pixel = 0;
  for (start_y = 0; start_y < filter->height && !did_we_find_a_logo_pixel; start_y++)
  {
    for (x = 0; x < filter->width; x++)
    {
      did_we_find_a_logo_pixel |= test_filter(filter, x, start_y);
    }
  }
  start_y--;

  /* Right bound. */
  did_we_find_a_logo_pixel = 0;
  for (end_y = filter->height - 1; end_y > start_y && !did_we_find_a_logo_pixel; end_y--)
  {
    for (x = 0; x < filter->width; x++)
    {
      did_we_find_a_logo_pixel |= test_filter(filter, x, end_y);
    }
  }
  end_y++;

  *posx1 = start_x;
  *posy1 = start_y;
  *posx2 = end_x;
  *posy2 = end_y;

  return;
}

static void destroy_masks(vf_instance_t * vf)
{
  int a, b;

  /* Load values from the vf->priv struct for faster dereferencing. */
  int * * * mask = vf->priv->mask;
  int max_mask_size = vf->priv->max_mask_size;

  if (mask == NULL)
    return; /* Nothing allocated, so return before we segfault. */

  /* Free all allocated memory. */
  for (a = 0; a <= max_mask_size; a++) /* Loop through each mask. */
  {
    for (b = -a; b <= a; b++) /* Loop through each scanline in a mask. */
    {
      free(mask[a][b + a]); /* Free a scanline. */
    }
    free(mask[a]); /* Free a mask. */
  }
  free(mask); /* Free the array of pointers pointing to the masks. */

  /* Set the pointer to NULL, so that any duplicate calls to this function will not cause a crash. */
  vf->priv->mask = NULL;

  return;
}

static void initialize_masks(vf_instance_t * vf)
{
  int a, b, c;

  /* Load values from the vf->priv struct for faster dereferencing. */
  int * * * mask = vf->priv->mask;
  int max_mask_size = vf->priv->max_mask_size; /* This tells us how many masks we'll need to generate. */

  /* Create a circular mask for each size up to max_mask_size. When the filter is applied, the mask size is
     determined on a pixel by pixel basis, with pixels nearer the edge of the logo getting smaller mask sizes. */
  mask = (int * * *) safe_malloc(sizeof(int * *) * (max_mask_size + 1));
  for (a = 0; a <= max_mask_size; a++)
  {
    mask[a] = (int * *) safe_malloc(sizeof(int *) * ((a * 2) + 1));
    for (b = -a; b <= a; b++)
    {
      mask[a][b + a] = (int *) safe_malloc(sizeof(int) * ((a * 2) + 1));
      for (c = -a; c <= a; c++)
      {
        if ((b * b) + (c * c) <= (a * a)) /* Circular 0/1 mask. */
          mask[a][b + a][c + a] = 1;
        else
          mask[a][b + a][c + a] = 0;
      }
    }
  }

  /* Store values back to vf->priv so they aren't lost after the function returns. */
  vf->priv->mask = mask;

  return;
}

static void convert_mask_to_strength_mask(vf_instance_t * vf, pgm_structure * mask)
{
  int x, y; /* Used by our for loops to go through every single pixel in the picture one at a time. */
  int has_anything_changed = 1; /* Used by the main while() loop to know if anything changed on the last erosion. */
  int current_pass = 0; /* How many times we've gone through the loop. Used in the in-place erosion algorithm
                           and to get us max_mask_size later on. */
  int max_mask_size; /* This will record how large a mask the pixel that is the furthest from the edge of the logo
                           (and thus the neediest) is. */
  char * current_pixel = mask->pixel; /* This stores the actual pixel data. */

  /* First pass, set all non-zero values to 1. After this loop finishes, the data should be considered numeric
     data for the filter, not color data. */
  for (x = 0; x < mask->height * mask->width; x++, current_pixel++)
    if(*current_pixel) *current_pixel = 1;

  /* Second pass and future passes. For each pass, if a pixel is itself the same value as the current pass,
     and its four neighbors are too, then it is incremented. If no pixels are incremented by the end of the pass,
     then we go again. Edge pixels are counted as always excluded (this should be true anyway for any sane mask,
     but if it isn't this will ensure that we eventually exit). */
  while (has_anything_changed)
  {
    current_pass++;
    current_pixel = mask->pixel;

    has_anything_changed = 0; /* If this doesn't get set by the end of this pass, then we're done. */

    for (y = 1; y < mask->height - 1; y++)
    {
      for (x = 1; x < mask->width - 1; x++)
      {
        /* Apply the in-place erosion transform. It is based on the following two premises: 1 - Any pixel that fails 1 erosion
           will fail all future erosions. 2 - Only pixels having survived all erosions up to the present will be >= to
           current_pass. It doesn't matter if it survived the current pass, failed it, or hasn't been tested yet. */
        if (*current_pixel >= current_pass && /* By using >= instead of ==, we allow the algorithm to work in place. */
            *(current_pixel + 1) >= current_pass &&
            *(current_pixel - 1) >= current_pass &&
            *(current_pixel + mask->width) >= current_pass &&
            *(current_pixel - mask->width) >= current_pass)
         {
           (*current_pixel)++; /* Increment the value since it still has not been eroded, as evidenced by the if statement
                                  that just evaluated to true. */
           has_anything_changed = 1;
         }
        current_pixel++;
      }
    }
  }

  /* Apply the fudge factor, which will increase the size of the mask a little to reduce jitter at the cost of more blur. */
  for (y = 1; y < mask->height - 1; y++)
  {
   for (x = 1; x < mask->width - 1; x++)
    {
      mask->pixel[(y * mask->width) + x] = apply_mask_fudge_factor(mask->pixel[(y * mask->width) + x]);
    }
  }

  max_mask_size = current_pass + 1; /* As a side-effect, we now know the maximum mask size, which we'll use to generate our masks. */
  max_mask_size = apply_mask_fudge_factor(max_mask_size); /* Apply the fudge factor to this number too, since we must
                                                             ensure that enough masks are generated. */
  vf->priv->max_mask_size = max_mask_size; /* Commit the newly calculated max_mask_size to the vf->priv struct. */

  return;
}

static void get_blur(const vf_instance_t * const vf, unsigned int * const value_out, const pgm_structure * const logo_mask,
              const mp_image_t * const image, const int x, const int y, const int plane)
{
  int mask_size; /* Mask size tells how large a circle to use. The radius is about (slightly larger than) mask size. */
  /* Get values from vf->priv for faster dereferencing. */
  int * * * mask = vf->priv->mask;

  int start_posx, start_posy, end_posx, end_posy;
  int i, j;
  unsigned int accumulator = 0, divisor = 0;
  const unsigned char * mask_read_position; /* What pixel we are reading out of the circular blur mask. */
  const unsigned char * logo_mask_read_position; /* What pixel we are reading out of the filter image. */

  /* Prepare our bounding rectangle and clip it if need be. */
  mask_size = test_filter(logo_mask, x, y);
  start_posx = max(0, x - mask_size);
  start_posy = max(0, y - mask_size);
  end_posx = min(image->width - 1, x + mask_size);
  end_posy = min(image->height - 1, y + mask_size);

  mask_read_position = image->planes[plane] + (image->stride[plane] * start_posy) + start_posx;
  logo_mask_read_position = logo_mask->pixel + (start_posy * logo_mask->width) + start_posx;

  for (j = start_posy; j <= end_posy; j++)
  {
    for (i = start_posx; i <= end_posx; i++)
    {
      if (!(*logo_mask_read_position) && mask[mask_size][i - start_posx][j - start_posy])
      { /* Check to see if this pixel is in the logo or not. Only use the pixel if it is not. */
        accumulator += *mask_read_position;
        divisor++;
      }

      mask_read_position++;
      logo_mask_read_position++;
    }

    mask_read_position += (image->stride[plane] - ((end_posx + 1) - start_posx));
    logo_mask_read_position += (logo_mask->width - ((end_posx + 1) - start_posx));
  }

  if (divisor == 0) /* This means that not a single pixel is outside of the logo, so we have no data. */
  { /* We should put some eye catching value here, to indicate the flaw to the user. */
    *value_out = 255;
  }
  else /* Else we need to normalise the data using the divisor. */
  {
    *value_out = (accumulator + (divisor / 2)) / divisor; /* Divide, taking into account average rounding error. */
  }

  return;
}

static void destroy_pgm(pgm_structure * to_be_destroyed)
{
  if (to_be_destroyed == NULL)
    return; /* Don't do anything if a NULL pointer was passed it. */

  /* Internally allocated memory. */
  if (to_be_destroyed->pixel != NULL)
  {
    free(to_be_destroyed->pixel);
    to_be_destroyed->pixel = NULL;
  }

  /* Free the actual struct instance. This is done here and not by the calling function. */
  free(to_be_destroyed);
}

static void load_pgm_skip(FILE *f) {
  int c, comment = 0;
  do {
    c = fgetc(f);
    if (c == '#')
      comment = 1;
    if (c == '\n')
      comment = 0;
  } while (c != EOF && (isspace(c) || comment));
  ungetc(c, f);
}

#define REMOVE_LOGO_LOAD_PGM_ERROR_MESSAGE(message) {mp_msg(MSGT_VFILTER, MSGL_ERR, message); return NULL;}

static pgm_structure * load_pgm(const char * file_name)
{
  int maximum_greyscale_value;
  FILE * input;
  int pnm_number;
  pgm_structure * new_pgm = (pgm_structure *) safe_malloc (sizeof(pgm_structure));
  char * write_position;
  char * end_position;
  int image_size; /* width * height */

  if((input = fopen(file_name, "rb")) == NULL) REMOVE_LOGO_LOAD_PGM_ERROR_MESSAGE("[vf]remove-logo: Unable to open file. File not found or insufficient permissions.\n");

  /* Parse the PGM header. */
  if (fgetc(input) != 'P') REMOVE_LOGO_LOAD_PGM_ERROR_MESSAGE("[vf]remove-logo: File is not a valid PGM or PPM file.\n");
  pnm_number = fgetc(input) - '0';
  if (pnm_number != 5 && pnm_number != 6) REMOVE_LOGO_LOAD_PGM_ERROR_MESSAGE("[vf]remove-logo: Invalid PNM file. Only raw PGM (Portable Gray Map) and raw PPM (Portable Pixel Map) subtypes are allowed.\n");
  load_pgm_skip(input);
  if (fscanf(input, "%i", &(new_pgm->width)) != 1) REMOVE_LOGO_LOAD_PGM_ERROR_MESSAGE("[vf]remove-logo: Invalid PGM/PPM header.\n");
  load_pgm_skip(input);
  if (fscanf(input, "%i", &(new_pgm->height)) != 1) REMOVE_LOGO_LOAD_PGM_ERROR_MESSAGE("[vf]remove-logo: Invalid PGM/PPM header.\n");
  load_pgm_skip(input);
  if (fscanf(input, "%i", &maximum_greyscale_value) != 1) REMOVE_LOGO_LOAD_PGM_ERROR_MESSAGE("[vf]remove-logo: Invalid PGM/PPM header.\n");
  if (maximum_greyscale_value >= 256) REMOVE_LOGO_LOAD_PGM_ERROR_MESSAGE("[vf]remove_logo: Only 1 byte per pixel (pgm) or 1 byte per color value (ppm) are supported.\n");
  load_pgm_skip(input);

  new_pgm->pixel = (unsigned char *) safe_malloc (sizeof(unsigned char) * new_pgm->width * new_pgm->height);

  /* Load the pixels. */
  /* Note: I am aware that fgetc(input) isn't the fastest way of doing things, but it is quite compact and the code only runs once when the filter is initialized.*/
  image_size = new_pgm->width * new_pgm->height;
  end_position = new_pgm->pixel + image_size;
  for (write_position = new_pgm->pixel; write_position < end_position; write_position++)
  {
    *write_position = fgetc(input);
    if (pnm_number == 6) /* This tests to see if the file is a PPM file. */
    { /* If it is, then consider the pixel set if any of the three color channels are set. Since we just care about == 0 or != 0, a bitwise or will do the trick. */
      *write_position |= fgetc(input);
      *write_position |= fgetc(input);
    }
  }

  return new_pgm;
}

static pgm_structure * generate_half_size_image(vf_instance_t * vf, pgm_structure * input_image)
{
  int x, y;
  pgm_structure * new_pgm = (pgm_structure *) safe_malloc (sizeof(pgm_structure));
  int has_anything_changed = 1;
  int current_pass;
  int max_mask_size;
  char * current_pixel;

  new_pgm->width = input_image->width / 2;
  new_pgm->height = input_image->height / 2;
  new_pgm->pixel = (unsigned char *) safe_malloc (sizeof(unsigned char) * new_pgm->width * new_pgm->height);

  /* Copy over the image data, using the average of 4 pixels for to calculate each downsampled pixel. */
  for (y = 0; y < new_pgm->height; y++)
    for (x = 0; x < new_pgm->width; x++)
    {
      /* Set the pixel if there exists a non-zero value in the source pixels, else clear it. */
      new_pgm->pixel[(y * new_pgm->width) + x] = input_image->pixel[((y << 1) * input_image->width) + (x << 1)] ||
                                                 input_image->pixel[((y << 1) * input_image->width) + (x << 1) + 1] ||
                                                 input_image->pixel[(((y << 1) + 1) * input_image->width) + (x << 1)] ||
                                                 input_image->pixel[(((y << 1) + 1) * input_image->width) + (x << 1) + 1];
      new_pgm->pixel[(y * new_pgm->width) + x] = min(1, new_pgm->pixel[(y * new_pgm->width) + x]);
    }

  /* Now we need to recalculate the numbers for the smaller size. Just using the old_value / 2 can cause subtle
     and fairly rare, but very nasty, bugs. */

  current_pixel = new_pgm->pixel;
  /* First pass, set all non-zero values to 1. */
  for (x = 0; x < new_pgm->height * new_pgm->width; x++, current_pixel++)
    if(*current_pixel) *current_pixel = 1;

  /* Second pass and future passes. For each pass, if a pixel is itself the same value as the current pass,
     and its four neighbors are too, then it is incremented. If no pixels are incremented by the end of the pass,
     then we go again. Edge pixels are counted as always excluded (this should be true anyway for any sane mask,
     but if it isn't this will ensure that we eventually exit). */
  current_pass = 0;
  while (has_anything_changed)
  {
    current_pass++;

    has_anything_changed = 0; /* If this doesn't get set by the end of this pass, then we're done. */

    for (y = 1; y < new_pgm->height - 1; y++)
    {
      for (x = 1; x < new_pgm->width - 1; x++)
      {
        if (new_pgm->pixel[(y * new_pgm->width) + x] >= current_pass && /* By using >= instead of ==, we allow the algorithm to work in place. */
            new_pgm->pixel[(y * new_pgm->width) + (x + 1)] >= current_pass &&
            new_pgm->pixel[(y * new_pgm->width) + (x - 1)] >= current_pass &&
            new_pgm->pixel[((y + 1) * new_pgm->width) + x] >= current_pass &&
            new_pgm->pixel[((y - 1) * new_pgm->width) + x] >= current_pass)
         {
           new_pgm->pixel[(y * new_pgm->width) + x]++; /* Increment the value since it still has not been eroded,
                                                    as evidenced by the if statement that just evaluated to true. */
           has_anything_changed = 1;
         }
      }
    }
  }

  for (y = 1; y < new_pgm->height - 1; y++)
  {
   for (x = 1; x < new_pgm->width - 1; x++)
    {
      new_pgm->pixel[(y * new_pgm->width) + x] = apply_mask_fudge_factor(new_pgm->pixel[(y * new_pgm->width) + x]);
    }
  }

  max_mask_size = current_pass + 1; /* As a side-effect, we now know the maximum mask size, which we'll use to generate our masks. */
  max_mask_size = apply_mask_fudge_factor(max_mask_size);
  /* Commit the newly calculated max_mask_size to the vf->priv struct. */
  vf->priv->max_mask_size = max(max_mask_size, vf->priv->max_mask_size);

  return new_pgm;
}

static unsigned int find_best(struct vf_instance *vf){
  int is_format_okay = vf_next_query_format(vf, IMGFMT_YV12);
  if ((is_format_okay & VFCAP_CSP_SUPPORTED_BY_HW) || (is_format_okay & VFCAP_CSP_SUPPORTED))
    return IMGFMT_YV12;
  else
    return 0;
}

//===========================================================================//

static int config(struct vf_instance *vf, int width, int height, int d_width, int d_height, unsigned int flags, unsigned int outfmt)
{
  if(!(vf->priv->fmt=find_best(vf)))
    return 0;
  else
    return vf_next_config(vf,width,height,d_width,d_height,flags,vf->priv->fmt);
}

static void convert_yv12(const vf_instance_t * const vf, const char * const source, const int source_stride,
                         const mp_image_t * const source_image, const int width, const int height,
                         char * const destination, const int destination_stride, int is_image_direct, pgm_structure * filter,
                         const int plane, const int logo_start_x, const int logo_start_y, const int logo_end_x, const int logo_end_y)
{
  int y;
  int x;

  /* These pointers point to where we are getting our pixel data (inside mpi) and where we are storing it (inside dmpi). */
  const unsigned char * source_line;
  unsigned char * destination_line;

  if (!is_image_direct)
    memcpy_pic(destination, source, width, height, destination_stride, source_stride);

  for (y = logo_start_y; y <= logo_end_y; y++)
  {
    source_line = (const unsigned char *) source + (source_stride * y);
    destination_line = (unsigned char *) destination + (destination_stride * y);

    for (x = logo_start_x; x <= logo_end_x; x++)
    {
      unsigned int output;

      if (filter->pixel[(y * filter->width) + x]) /* Only process if we are in the logo. */
      {
        get_blur(vf, &output, filter, source_image, x, y, plane);
        destination_line[x] = output;
      }
      else /* Else just copy the data. */
        if (!is_image_direct)
          destination_line[x] = source_line[x];
    }
  }
}

static int put_image(struct vf_instance *vf, mp_image_t *mpi, double pts){
    mp_image_t *dmpi;

    dmpi=vf_get_image(vf->next,vf->priv->fmt,
        MP_IMGTYPE_TEMP, MP_IMGFLAG_ACCEPT_STRIDE,
        mpi->w, mpi->h);

    /* Check to make sure that the filter image and the video stream are the same size. */
    if (vf->priv->filter->width != mpi->w || vf->priv->filter->height != mpi->h)
    {
      mp_msg(MSGT_VFILTER,MSGL_ERR, "Filter image and video stream are not of the same size. (Filter: %d x %d, Stream: %d x %d)\n",
             vf->priv->filter->width, vf->priv->filter->height, mpi->w, mpi->h);
      return 0;
    }

    switch(dmpi->imgfmt){
    case IMGFMT_YV12:
          convert_yv12(vf, mpi->planes[0],  mpi->stride[0], mpi, mpi->w, mpi->h,
                          dmpi->planes[0], dmpi->stride[0],
                          mpi->flags & MP_IMGFLAG_DIRECT, vf->priv->filter, 0,
                          vf->priv->bounding_rectangle_posx1, vf->priv->bounding_rectangle_posy1,
                          vf->priv->bounding_rectangle_posx2, vf->priv->bounding_rectangle_posy2);
          convert_yv12(vf, mpi->planes[1],  mpi->stride[1], mpi, mpi->w / 2, mpi->h / 2,
                          dmpi->planes[1], dmpi->stride[1],
                          mpi->flags & MP_IMGFLAG_DIRECT, vf->priv->half_size_filter, 1,
                          vf->priv->bounding_rectangle_half_size_posx1, vf->priv->bounding_rectangle_half_size_posy1,
                          vf->priv->bounding_rectangle_half_size_posx2, vf->priv->bounding_rectangle_half_size_posy2);
          convert_yv12(vf, mpi->planes[2],  mpi->stride[2], mpi, mpi->w / 2, mpi->h / 2,
                          dmpi->planes[2], dmpi->stride[2],
                          mpi->flags & MP_IMGFLAG_DIRECT, vf->priv->half_size_filter, 2,
                          vf->priv->bounding_rectangle_half_size_posx1, vf->priv->bounding_rectangle_half_size_posy1,
                          vf->priv->bounding_rectangle_half_size_posx2, vf->priv->bounding_rectangle_half_size_posy2);
          break;

    default:
        mp_msg(MSGT_VFILTER,MSGL_ERR,"Unhandled format: 0x%X\n",dmpi->imgfmt);
        return 0;
    }

    return vf_next_put_image(vf,dmpi, pts);
}

//===========================================================================//

static int query_format(struct vf_instance *vf, unsigned int fmt)
{
  if (fmt == IMGFMT_YV12)
    return vf_next_query_format(vf, IMGFMT_YV12);
  else
    return 0;
}

static void uninit(vf_instance_t *vf)
{
  /* Destroy our masks and images. */
  destroy_pgm(vf->priv->filter);
  destroy_pgm(vf->priv->half_size_filter);
  destroy_masks(vf);

  /* Destroy our private structure that had been used to store those masks and images. */
  free(vf->priv);

  return;
}

static int vf_open(vf_instance_t *vf, char *args)
{
  vf->priv = safe_malloc(sizeof(vf_priv_s));
  vf->uninit = uninit;

  /* Load our filter image. */
  if (args)
    vf->priv->filter = load_pgm(args);
  else
  {
    mp_msg(MSGT_VFILTER, MSGL_ERR, "[vf]remove_logo usage: remove_logo=/path/to/filter_image_file.pgm\n");
    free(vf->priv);
    return 0;
  }

  if (vf->priv->filter == NULL)
  {
    /* Error message was displayed by load_pgm(). */
    free(vf->priv);
    return 0;
  }

  /* Create the scaled down filter image for the chroma planes. */
  convert_mask_to_strength_mask(vf, vf->priv->filter);
  vf->priv->half_size_filter = generate_half_size_image(vf, vf->priv->filter);

  /* Now that we know how many masks we need (the info is in vf), we can generate the masks. */
  initialize_masks(vf);

  /* Calculate our bounding rectangles, which determine in what region the logo resides for faster processing. */
  calculate_bounding_rectangle(&vf->priv->bounding_rectangle_posx1, &vf->priv->bounding_rectangle_posy1,
                               &vf->priv->bounding_rectangle_posx2, &vf->priv->bounding_rectangle_posy2,
                                vf->priv->filter);
  calculate_bounding_rectangle(&vf->priv->bounding_rectangle_half_size_posx1,
                               &vf->priv->bounding_rectangle_half_size_posy1,
                               &vf->priv->bounding_rectangle_half_size_posx2,
                               &vf->priv->bounding_rectangle_half_size_posy2,
                                vf->priv->half_size_filter);

  vf->config=config;
  vf->put_image=put_image;
  vf->query_format=query_format;
  return 1;
}

const vf_info_t vf_info_remove_logo = {
    "Removes a tv logo based on a mask image.",
    "remove-logo",
    "Robert Edele",
    "",
    vf_open,
    NULL
};

//===========================================================================//

---