← Back to Patent Explorer
US5666441A Expired / Lapsed US ⏱️ 0.0 years remaining

Computer vision system to detect 3-D rectangular objects

Assignee: Texas Instruments Inc
•
Filing: 1995-08-30
•
Granted: 1997-09-09
•
Expires: 2015-08-30
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract In general, the invention includes a method and system of rectangular solid detection comprising: receiving an image of data; detecting edges from the image of data; finding lines from the image of data; finding junctions from the lines; filtering junctions and lines that meet a first set of certain criteria; grouping the junctions and lines that meet a second set of certain criteria; and detecting whether a rectangular solid exists in the image according to the grouping. The criteria includes using triplets of lines and fork junctions. The system and method may also analyze a single frame, or a single frame paired with a reference frame.

Inventors

  • 👤 Kashi Rao
  • 👤 Piyush Sarwal

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 21:33
CPC Classifications
G; G06; G06V; G06V10/00; G06V10/40; G06V10/44; G06V10/457; G06V10/70; G06V10/74; G06V10/75; G06V10/757

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 145 words
A method of rectangular solid detection comprising: receiving a reference image of a scene; receiving a new image of said scene; differencing said new image of said scene from said reference image of said scene to produce a differenced image of said scene with a modified differencing technique; and identifying a rectangular solid from said differenced image of said scene wherein said identifying said rectangular solid includes: detecting edges from said differenced image of said scene; finding lines from said edges and said differenced image of said scene; finding fork junctions from lines and said differenced image of said scene; filtering fork junctions and triplets of lines that meet a first set of certain criteria; grouping said junctions and said triplets of lines that meet a second set of certain criteria; and determining whether a rectangular solid exists in said image according to said grouping.
Claim 2
Independent Claim 145 words
A method of rectangular solid detection comprising: receiving a reference image of a scene; receiving a new image of said scene; differencing said new image of said scene from said reference image of said scene to produce a differenced image of said scene with a modified differencing technique; and identifying a rectangular solid from said differenced image of said scene wherein said identifying said rectangular solid includes: detecting edges from said differenced image of said scene; finding lines from said edges and said differenced image of said scene; finding fork junctions from lines and said differenced image of said scene; filtering fork junctions and triplets of lines that meet a first set of certain criteria; grouping said junctions and said triplets of lines that meet a second set of certain criteria; and determining whether a rectangular solid exists in said image according to said grouping.
Claim 3
Dependent Claim 33 words
The method of claim 1, wherein said finding fork junctions utilizes a quality factor, wherein said quality factor relates to a position of an intersecting point of two lines of said fork junction.
Claim 4
Dependent Claim 50 words
The method of claim 1, wherein said first set of certain criteria includes: accepting said triplets of lines with outer lines parallel and overlapping; rejecting said fork junctions with angles greater 270°; rejecting said fork junctions with two obtuse angles and one angle acute; and accepting all remaining fork junctions.
Claim 5
Dependent Claim 44 words
The method of claim 1, wherein said second set of certain criteria includes: grouping said fork junctions and said triplets of lines that share two lines; grouping said triplets of lines that share two lines; and grouping said fork junctions that share one line.
Claim 6
Independent Claim 96 words
A method of rectangular solid detection comprising: receiving an image of a scene; detecting edges from said image of said scene; finding lines from said edges and said image of said scene; finding triplets of lines from said lines and said image of said scene; finding fork junctions from said lines; filtering fork junctions and triplets of lines that meet a first set of certain criteria; grouping said fork junctions and triplets of lines that meet a second set of certain criteria; and determining whether a rectangular solid exists in said image according to said grouping.
Claim 7
Independent Claim 96 words
A method of rectangular solid detection comprising: receiving an image of a scene; detecting edges from said image of said scene; finding lines from said edges and said image of said scene; finding triplets of lines from said lines and said image of said scene; finding fork junctions from said lines; filtering fork junctions and triplets of lines that meet a first set of certain criteria; grouping said fork junctions and triplets of lines that meet a second set of certain criteria; and determining whether a rectangular solid exists in said image according to said grouping.
Claim 8
Dependent Claim 50 words
The method of claim 5, wherein said first set of certain criteria includes: accepting said triplets of lines with outer lines parallel and overlapping; rejecting said fork junctions with angles greater 270°; rejecting said fork junctions with two obtuse angles and one angle acute; and accepting all remaining fork junctions.
Claim 9
Dependent Claim 33 words
The method of claim 5, wherein said finding fork junctions utilizes a quality factor, wherein said quality factor relates to a position of an intersecting point of two lines of said fork junction.
Claim 10
Dependent Claim 43 words
The method of claim 5, wherein said second set of certain criteria includes grouping said fork junctions and said triplets of lines that share two lines; grouping triplets of lines that share two lines; and grouping said fork junctions that share one line.
Claim 11
Dependent Claim 38 words
The method of claim 8, wherein said grouping of said fork junctions that share one line includes grouping said fork junctions only where said one line is a center line of at least one of said fork junctions.
Claim 12
Independent Claim 187 words
A method of rectangular solid detection comprising: receiving an image of a scene; detecting edges from said image of said scene; finding lines from said edges and said image of said scene; finding triplets of lines from said lines and said image of said scene; finding fork junctions from said lines; filtering fork junctions and triplets of lines, wherein said filtering includes: accepting said triplets of lines with outer lines parallel and overlapping to produce an accepted set of triplet of lines; rejecting said fork junctions with angles greater 270°; rejecting said fork junctions with two obtuse angles and one angle acute; and accepting all remaining fork junctions to produce an accepted set of fork junctions; grouping said fork junctions and triplets of lines, wherein said grouping includes: grouping said accepted set of fork junctions and said accepted set of triplets of lines that share two lines; grouping said accepted set of triplets of lines that share two lines; and grouping identifying said accepted set of fork junctions that share one line; and determining whether a rectangular solid exists in said image when a grouping is formed.
Claim 13
Independent Claim 187 words
A method of rectangular solid detection comprising: receiving an image of a scene; detecting edges from said image of said scene; finding lines from said edges and said image of said scene; finding triplets of lines from said lines and said image of said scene; finding fork junctions from said lines; filtering fork junctions and triplets of lines, wherein said filtering includes: accepting said triplets of lines with outer lines parallel and overlapping to produce an accepted set of triplet of lines; rejecting said fork junctions with angles greater 270°; rejecting said fork junctions with two obtuse angles and one angle acute; and accepting all remaining fork junctions to produce an accepted set of fork junctions; grouping said fork junctions and triplets of lines, wherein said grouping includes: grouping said accepted set of fork junctions and said accepted set of triplets of lines that share two lines; grouping said accepted set of triplets of lines that share two lines; and grouping identifying said accepted set of fork junctions that share one line; and determining whether a rectangular solid exists in said image when a grouping is formed.

References Cited (Backward Citations)

US4249207A Cited
US5291563A Cited
US5093869A Cited
US5210799A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-09-08 2001-03-10 2001-09-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-09-08 2005-03-10 2005-09-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-09-08 2009-03-10 2009-09-09 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag