nest-open-source / nest-android-app / ffmpeg / 8e1cc55b733ae723de9931f20a13731bed8162f5 / . / libavfilter / bbox.c

/* | |

* Copyright (c) 2005 Robert Edele <yartrebo@earthlink.net> | |

* | |

* This file is part of FFmpeg. | |

* | |

* FFmpeg is free software; you can redistribute it and/or | |

* modify it under the terms of the GNU Lesser General Public | |

* License as published by the Free Software Foundation; either | |

* version 2.1 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 | |

* Lesser General Public License for more details. | |

* | |

* You should have received a copy of the GNU Lesser 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 "bbox.h" | |

int ff_calculate_bounding_box(FFBoundingBox *bbox, | |

const uint8_t *data, int linesize, int w, int h, | |

int min_val) | |

{ | |

int x, y; | |

int start_x; | |

int start_y; | |

int end_x; | |

int end_y; | |

const uint8_t *line; | |

/* left bound */ | |

for (start_x = 0; start_x < w; start_x++) | |

for (y = 0; y < h; y++) | |

if ((data[y * linesize + start_x] > min_val)) | |

goto outl; | |

outl: | |

if (start_x == w) /* no points found */ | |

return 0; | |

/* right bound */ | |

for (end_x = w - 1; end_x >= start_x; end_x--) | |

for (y = 0; y < h; y++) | |

if ((data[y * linesize + end_x] > min_val)) | |

goto outr; | |

outr: | |

/* top bound */ | |

line = data; | |

for (start_y = 0; start_y < h; start_y++) { | |

for (x = 0; x < w; x++) | |

if (line[x] > min_val) | |

goto outt; | |

line += linesize; | |

} | |

outt: | |

/* bottom bound */ | |

line = data + (h-1)*linesize; | |

for (end_y = h - 1; end_y >= start_y; end_y--) { | |

for (x = 0; x < w; x++) | |

if (line[x] > min_val) | |

goto outb; | |

line -= linesize; | |

} | |

outb: | |

bbox->x1 = start_x; | |

bbox->y1 = start_y; | |

bbox->x2 = end_x; | |

bbox->y2 = end_y; | |

return 1; | |

} |