Function Repository Resource:

FindImageBoundingBoxes

Calculate the bounding rectangles of elements in a binary image

Contributed by: Pedro Cabral (Wolfram Research)

ResourceFunction["FindImageBoundingBoxes"][img]

returns a list containing the bounding rectangles of the elements of the binary image img.

Details and Options

ResourceFunction["FindImageBoundingBoxes"] is a low-level version of ImageBoundingBoxes. Instead of finding and bounding entities or objects using artificial intelligence, ResourceFunction["FindImageBoundingBoxes"] searches for different morphological components in a binary image, independent of their type or shape.

Examples

Basic Examples (2)

Find all of the bounding boxes of all the elements of an image:

In[1]:=

$ResourceFunction["FindImageBoundingBoxes"][\!\(\* GraphicsBox[ TagBox[RasterBox[CompressedData[" 1:eJzt3c1OIkEUQOHSlUtfwbdw69ItxgeAiMQNJmBifHrUqAvtWwuBqrrknC+Z SUwmTZ07/HQ3DV4tnmeP56WU7cXHX7P5681mM3+7u/z44X69fVqtlw+365fl arm5Xnz+s3L2/ef/dr/ttY0Ttvtr9IL6muSzBhDkowYQ9nMGEOfj+zEDsB/d X8vH90MGYD+7n/78Z7/96H768U+K/qHzHpw//j43Mj/Foy5LfpIBjLrdHI+B ITc6fgCl/7NwlO8r7+hVdRPncwZgv/3g/lo+ZQD0fvr933770f30/V98f7bj 3/7g+WnOf40Dzy8Zzn+PR26XJEmSJEmSJEmSJKmF1m/FZ36vv/WlGLmv9Wh9 KU7ya31aX4qV/Fqv1pfiTbafawDT5R13fcH2Mw0gWt4x1xduP9EA4P3x8o63 vsr20wzAfvvB/bXlHWt91e0nGUDz5eXOx/fTH//2t15e7nx8f/tvwc6d3+Fb wFPn9/gW+NT5PX4LQOr8Lr8FInF9aX/+9+dWmm36YF3/e5IOolN75gdCa8mf CFtL/kLY2uSFljWAaT5qAFE+aQDw/jifMwD77Qf31/IpA6D30+//9tuP7qfv /+L76ce/+PMf+PNf+POfhX7++8tB7eC59X2XKh34cwf8tQO+7wDfdwzyUQMI +zkDiPPx/ZgB2I/ur+Xj+yEDgOfjH//220/Ox+//44//6Mf/+PM/+PN/+PO/ hX7+/wu5XZL2Rn7pYO88wPce4UcP8KPHIJ80gDAfNAB4fyUfMwD77Qf3V/Md wOiV9QHPtx/e77vn7HzfPfejh/B8P3roRw/96GFJ+9WLkiRJkiRJkiRJkiRJ kiRJkiRJkiRJkiRJkiRJJ+kdo4aFmg== "], {{0, 192.}, {192., 0}}, {0, 255}, ColorFunction->GrayLevel, ImageResolution->96], BoxForm`ImageTag[ "Byte", ColorSpace -> "Grayscale", Interleaving -> None], Selectable->False], DefaultBaseStyle->"ImageGraphics", ImageSizeRaw->{192., 192.}, PlotRange->{{0, 192.}, {0, 192.}}]\)]$

Out[1]=

Find all of the bounding boxes:

In[2]:=

$ResourceFunction["FindImageBoundingBoxes"][\!\(\* GraphicsBox[ TagBox[RasterBox[CompressedData[" 1:eJztnE1uE0EQRg0rllyBW7BlyTaIAyTCRGyM5CAhTj8kUoBg9/90VVd3vScR KR5r6nuV6XHPTON3d99vvr4+HA4Pbx5/3Nz+/HA+3/769Pbxl8+nh2/3p+OX j6cfx/vj+f3d09sOr57/AQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AABAI9sfRgcZwvaS0WH02TbPDdiuGJ1IlWt9Vw0I6TtqQFjfTwOc+8f0vTQA /zL/VRtT5r/uoVHkv/DYKPHPDo6JKfDPHR1T0+q/SgPy/rn2TE6r/yoNaNVf xT93fDv1z2xeyD9z/2N9//T9Lwf+V46pbSv6/28Z37Kufxz8ffuvPv/L4lx/ 8eu/Apzrr33/pwjn+ofLDoxOMwLf9gAAAAAAAAAAAPbwfcvO+S1b5/fsnT+z cf7MLqQv7G+qxUF/yXS2DrGwvlw6a0Ms4i8Vz9opJqYvFE/tFFOKrr/SGaYC VX+NAVYJ/nr+CgOsGvzx9+yvOf+ZyV++lESFFvBX0jfqL71mNzLA7PiLrtmN 2VvyF/zOhri+JX+x67KEvin/f0kl9mnEX7tyWl/bX712Rl/Xf0BxS/4Dquf0 Nf1HlDfkP6Q+/lb8xwTA37q/bAL88ccff6f+WX38tRiRIK+/tH+0oCV//ZKD 1r8k/SUSxTtuyD+0SbTgMP/4/Y/wqyL1RvrH7n/F2tK/3PPO+7e6MVE8pkQ1 sUKNkVIpuxez4R94/CGXy6R/aUjBXU/h3yGYd/+iBnQoI5NRct9O/E1d/9VG FN25E//g1NKTf/DSwpS/9H2BwE5d+Qf+r5Mt/wHPhfG35D9gXYh5f72S0pVK UNd/UVOhVB59/b9FdWrlGKBvDN/2APV4HjNDPjLMoD9jMkVgxuipASF99/5+ GhDW30LbB6aUI+2//lGR9HcwLBL+yXGxChH/KKPz9gb/KRvQLc6U/j0DTdiA roHm8++caDb/3pEm8+8faX7/dKbsu2byr85U9L7Z/YvFavc7t391evP6VSs8 GvKv5N+S37r+fv/Czwqj+hX+TQrW9aX90w2QUapioL+MUCXS/tJrSHcj7W/9 gUhxvOa/o2H5J8T9yyfNYyh0ave3voKqTGmHv/XVIEVGe/TNUyK0sn8JzvWH rIW2hXN9D+sXMjjXP1j/JAdYA89DzPcphg8Yz/7OJxjeJ1jO/bm+mMZfIuQ8 15eRmDuzT+Mfzrk7/Sz+WzBo+NUd++0buh+XooGvbmnLP6v/FnyxXmAO/7Co a//Lb65qNMDft/8c8z81/98KvjSw "], {{0, 192.}, {192., 0}}, {0, 255}, ColorFunction->GrayLevel, ImageResolution->96], BoxForm`ImageTag[ "Byte", ColorSpace -> "Grayscale", Interleaving -> None], Selectable->False], DefaultBaseStyle->"ImageGraphics", ImageSizeRaw->{192., 192.}, PlotRange->{{0, 192.}, {0, 192.}}]\)]$

Out[2]=

Highlight them with a RandomColor:

In[3]:=

$HighlightImage[\!\(\* GraphicsBox[ TagBox[RasterBox[CompressedData[" 1:eJztnE1uE0EQRg0rllyBW7BlyTaIAyTCRGyM5CAhTj8kUoBg9/90VVd3vScR KR5r6nuV6XHPTON3d99vvr4+HA4Pbx5/3Nz+/HA+3/769Pbxl8+nh2/3p+OX j6cfx/vj+f3d09sOr57/AQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AABAI9sfRgcZwvaS0WH02TbPDdiuGJ1IlWt9Vw0I6TtqQFjfTwOc+8f0vTQA /zL/VRtT5r/uoVHkv/DYKPHPDo6JKfDPHR1T0+q/SgPy/rn2TE6r/yoNaNVf xT93fDv1z2xeyD9z/2N9//T9Lwf+V46pbSv6/28Z37Kufxz8ffuvPv/L4lx/ 8eu/Apzrr33/pwjn+ofLDoxOMwLf9gAAAAAAAAAAAPbwfcvO+S1b5/fsnT+z cf7MLqQv7G+qxUF/yXS2DrGwvlw6a0Ms4i8Vz9opJqYvFE/tFFOKrr/SGaYC VX+NAVYJ/nr+CgOsGvzx9+yvOf+ZyV++lESFFvBX0jfqL71mNzLA7PiLrtmN 2VvyF/zOhri+JX+x67KEvin/f0kl9mnEX7tyWl/bX712Rl/Xf0BxS/4Dquf0 Nf1HlDfkP6Q+/lb8xwTA37q/bAL88ccff6f+WX38tRiRIK+/tH+0oCV//ZKD 1r8k/SUSxTtuyD+0SbTgMP/4/Y/wqyL1RvrH7n/F2tK/3PPO+7e6MVE8pkQ1 sUKNkVIpuxez4R94/CGXy6R/aUjBXU/h3yGYd/+iBnQoI5NRct9O/E1d/9VG FN25E//g1NKTf/DSwpS/9H2BwE5d+Qf+r5Mt/wHPhfG35D9gXYh5f72S0pVK UNd/UVOhVB59/b9FdWrlGKBvDN/2APV4HjNDPjLMoD9jMkVgxuipASF99/5+ GhDW30LbB6aUI+2//lGR9HcwLBL+yXGxChH/KKPz9gb/KRvQLc6U/j0DTdiA roHm8++caDb/3pEm8+8faX7/dKbsu2byr85U9L7Z/YvFavc7t391evP6VSs8 GvKv5N+S37r+fv/Czwqj+hX+TQrW9aX90w2QUapioL+MUCXS/tJrSHcj7W/9 gUhxvOa/o2H5J8T9yyfNYyh0ave3voKqTGmHv/XVIEVGe/TNUyK0sn8JzvWH rIW2hXN9D+sXMjjXP1j/JAdYA89DzPcphg8Yz/7OJxjeJ1jO/bm+mMZfIuQ8 15eRmDuzT+Mfzrk7/Sz+WzBo+NUd++0buh+XooGvbmnLP6v/FnyxXmAO/7Co a//Lb65qNMDft/8c8z81/98KvjSw "], {{0, 192.}, {192., 0}}, {0, 255}, ColorFunction->GrayLevel, ImageResolution->96], BoxForm`ImageTag[ "Byte", ColorSpace -> "Grayscale", Interleaving -> None], Selectable->False], DefaultBaseStyle->"ImageGraphics", ImageSizeRaw->{192., 192.}, PlotRange->{{0, 192.}, {0, 192.}}]\), Riffle[Table[RandomColor[], Length[%]], %]]$

Out[3]=

Possible Issues (2)

FindBoundingBoxes does not work with matrices or lists:

In[4]:=

$ResourceFunction["FindImageBoundingBoxes"][\!$\* TagBox[ RowBox[{"(", "", GridBox[{ {"1", "0", "0", "0"}, {"0", "1", "0", "0"}, {"0", "0", "1", "0"}, {"0", "0", "0", "1"} }, GridBoxAlignment->{"Columns" -> {{Center}}, "Rows" -> {{Baseline}}}, GridBoxSpacings->{"Columns" -> { Offset[ 0.27999999999999997`], { Offset[0.7]}, Offset[0.27999999999999997`]}, "Rows" -> { Offset[0.2], { Offset[0.4]}, Offset[0.2]}}], "", ")"}], Function[BoxForm`e$, MatrixForm[BoxForm`e$]]]$]$