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Coords/edge detect 2 colour image
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@cvp, thanks! Have been hacking more on the laptop lately.
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Hiya
So I don’t have an image it’s just in my head but initially yes I’m thinking rectangles black on white or white on black.They could be arbitrary sizes I’m thinking - I just want use them to create edges that I can repurpose as coordinates for building other elements with. -
Vision iOS framework looks perfect actually so yes please would be interested in how to implement such a thing in Pythonista for sure.
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I found another post regarding text recognition and iOS vision and recognise rectangle is mentioned there so cut out the text aspect and adapted it: (thanks jonb)
But I can’t get what I need from this - I have tried altering the VNDetectRectanglesRequest properties.
Basic issue is even though it’s a very simple image = seems to struggle identifying accurately the edges.from objc_util import * import ui ui_image=ui.Image.named('test:Gray21') ui_image.show() load_framework('Vision') VNDetectRectanglesRequest = ObjCClass('VNDetectRectanglesRequest') VNImageRequestHandler = ObjCClass('VNImageRequestHandler') handler = VNImageRequestHandler.alloc().initWithData_options_(ui_image.to_png(), None).autorelease() req = VNDetectRectanglesRequest.alloc().init().autorelease() req.maximumObservations=0 req.minimumSize=0.01 req.minimumAspectRatio=0.0 req.maximumAspectRatio=1.0 req.quadratureTolerance=10 success = handler.performRequests_error_([req], None) with ui.ImageContext(*tuple(ui_image.size) ) as ctx: ui_image.draw() for result in req.results(): cgpts=[result.bottomLeft(), result.topLeft(), result.topRight(), result.bottomRight(), result.bottomLeft()] verts = [(p.x*ui_image.size.w, (1-p.y)*ui_image.size.h) for p in cgpts] pth = ui.Path() pth.move_to(*verts[0]) for p in verts[1:]: pth.line_to(*p) ui.set_color('red') pth.stroke() x,y = verts[0] w,h =(verts[2][0]-x), (verts[2][1]-y) marked_img = ctx.get_image() marked_img.show()
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@rb not so bad with
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Hmm ok so your saying 2 colour works better - I only used that test image as I couldn’t work out how to upload an image here…
this is more like the kind of images I want to use though, ie long thin horizontal rectangles mostly - seems to struggle, try :iow:drag_256
It creates extra rectangles at top and bottom bounds- how can I remove these?
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@rb try with this, it works
with ui.ImageContext(400,300) as ctx: pth = ui.Path.rect(0,0,400,300) ui.set_color('black') pth.fill() pthr = ui.Path.rect(100,100,200,50) ui.set_color('white') pthr.fill() ui_image = ctx.get_image() #ui_image=ui.Image.named('iow:drag_256')
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@rb said:
I couldn’t work out how to upload an image here…
I use
import pyimgur,photos,clipboard,os,console i=photos.pick_image() if i: print(i.format) format = 'gif' if (i.format == 'GIF') else 'jpg' i.save('img.'+format) clipboard.set(pyimgur.Imgur("303d632d723a549").upload_image('img.'+format, title="Uploaded-Image").link) console.hud_alert("link copied!") os.remove('img.'+format)
With pyImgur from here
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Fwiw
https://forum.omz-software.com/topic/6016/recognize-text-from-picture/43?page=3Had a rectangle recognizer.
You might play with the quadratureTolerance -- you are only allowing rectangles with angles within 10 degrees -- you might increase that to the default of 30 to allow perspective.
Try adjusting minimumConfidence -- lower will allow more detections, at lower quality.
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Cheers everyone, Jon that’s where I nabbed that snippet from in first place! The issue is the proximity to the edge of the image I think, mine were very close to the edge so I tried a bigger black border and I did try messing with the numbers a bit on properties.Seems to work better but still not perfect.