Re: Cursor position on images

*To*: mathgroup at smc.vnet.net*Subject*: [mg129386] Re: Cursor position on images*From*: Murray Eisenberg <murray at math.umass.edu>*Date*: Thu, 10 Jan 2013 02:22:14 -0500 (EST)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*Delivered-to*: l-mathgroup@wolfram.com*Delivered-to*: mathgroup-newout@smc.vnet.net*Delivered-to*: mathgroup-newsend@smc.vnet.net*References*: <20130108040700.E610D687E@smc.vnet.net> <D4B463E6-BC50-4B29-BC5F-CD1BC32B318B@math.umass.edu> <5F5696D639DA7D4C842D85A250023D871E8C3C1A@DB3PRD0710MB393.eurprd07.prod.outlook.com> <A55386C3-D33B-479F-9A2E-40D1825EA910@math.umass.edu>

I discovered the source of the problem: on Mac OS X it's Command + Click instead of Alt + Click! And in the Documentation Center, e.g., ref/LocatorAutoCreate, it incorrectly and repeatedly gives Alt + Click, which is OK for Windows, but should be instead Command + Click for OS X. On Jan 9, 2013, at 9:16 AM, Murray Eisenberg <murray at math.umass.edu> wrote: > I still don't quite understand. > > In your original message, you included the following steps: > > Step 2: Enter the reference points at the plot axes into the input fields. Press Enter. > > Step3: Alt+Click on the point with x-coordinate x1. > This brings up the first locator visible as a circle. > Alt+Click on that with x2 which gives rise to the second locator. > Adjust the locators, if necessary. > Press the button ?Memorize scale X?. > > I think you're now saying to do things in an opposite order: > > (1) first put 2 by Alt+MouseClick put locators in two positions along, say, the x axis, > (2) type two corresponding x coordinates and > (3) then press the button "Memorize scale x", > (4) then pull the same locators in two points along the y axis, > (5) type the corresponding y values and > (6) press the corresponding button. > > I presume this new (1) has a typo and should be simply: > > (1) first put Alt+MouseClick put locators in two positions along, say, the x axis, > > Assuming this new, opposite, order is what you intended, > > Still, no locator appears when I Alt-click anywhere in the image = output after the copyCurve[pic] is evaluated. That's using Mathematica = 9.0.0 under Mac OS X 10.8.2. > > I now tried the same thing, with the same image, using the Windows = version of Mathematica 9.0.0 under Windows 7 (running in a virtual = machine in Parallels Desktop 8 on my same Mac). Now copyCurve _does_ = work. > > So something's wrong with copyCurve on Mac. (Of course Alt in the Mac = context means Option.) I tried the "obvious" things of Alt+Shift+Click, = but that still does not produce a Locator. > > Wait=85the problem is with Alt-Click in Mathematica under OS X, for = anything! For example, the code > > Manipulate[ > Graphics[{Line[u]}, PlotRange -> 2], {{u, {{-1, -1}, {1, 1}}}, > Locator, LocatorAutoCreate -> True}] > > from the Documentation Center does not work as expected in OS X: using = Alt-Click does not create a new Locator! > > [In your original message, you partially reversed steps (1) and (2). = There you said > On Jan 9, 2013, at 3:33 AM, Alexei Boulbitch <Alexei.Boulbitch at iee.lu> = wrote: > >> Dear Murray, >> >> In principle this: >> pic = ExampleData[{"TestImage", "Lena"}] >> copyCurve[pic] >> is exactly how it should be used. I could not, however, repeat = ExampleData[{"TestImage", "Lena"}] on my machine. It did not load the = image for a long time, and after 5 minutes waiting I aborted it and = copy-pasted Lena from Menu/Help/Image. I tried on my machine (Math9, PC, = Win XP) with Lena obtained this way and it works. It is only necessary = that the graphics you use has the head Image. Otherwise you can wrap it = with Image. It also worked for me with PC/XP/Math8 (in which I have = written it) and on PC/Win.7/Math9. I never tried it on Mac though. >> >> A minor thing is not quite correct with your sequence of actions. You = should first put 2 by Alt+MouseClick put locators in two positions = along, say, the x axis, type two corresponding x coordinates and then = press the button "Memorize scale x", then pull the same locators in two = points along the y axis, type the corresponding y values and press the = corresponding button. Then use the same 2 locators at the first 2 points = of the line you need to digitalize and add more locators where needed. = The order x before y or y before x is of no importance. But of course, = as soon as locators show up you immediately find the right way. >> >> Did you try to change the colour of the locators by the ColorSlider? = They are red by default and may be poorly visible with Lena on the = background. >> >> Best, Alexei >> >> Alexei BOULBITCH, Dr., habil. >> IEE S.A. >> ZAE Weiergewan, >> 11, rue Edmond Reuter, >> L-5326 Contern, LUXEMBOURG >> >> Office phone : +352-2454-2566 >> Office fax: +352-2454-3566 >> mobile phone: +49 151 52 40 66 44 >> >> e-mail: alexei.boulbitch at iee.lu >> >> >> -----Original Message----- >> From: Murray Eisenberg [mailto:murray at math.umass.edu] >> Sent: Tuesday, January 08, 2013 6:16 PM >> To: mathgroup >> Subject: Re: Cursor position on images >> >> Either I'm not understanding the instructions for copyCurve or else = something is not working right for Mathematica 9.0.0 on Mac OS X. = Example: >> >> pic = ExampleData[{"TestImage", "Lena"}] >> copyCurve[pic] >> >> I now type into the x1, y1, x2, y2 input fields the values 0, 0, 200, = 200 respectively and press Enter. >> >> When I use Alt+Click, nothing happens -- I don't see any Locator. >> >> I also tried Shift+Alt+Click in case that's required for Mac, but = still no action. >> >> On Jan 7, 2013, at 11:07 PM, Alexei Boulbitch = <Alexei.Boulbitch at iee.lu> wrote: >> >>> I am sure this is straightforward but I cannot quite see how to do = this. I have an image (jpg file, but could be any format if that = matters). I want to be able to left click on the image and mark the = point with a dot of some sort and collect the coordinates of the point = (the coordinate system is fairly arbitrary). I then want to be able to = repeat this as many times as required and end up with a list of the = coordinates of the points clicked on for further manipulation. Clickpane = should do the trick but I can't work out how. >>> >>> Any suggestions, thanks. >>> >>> Peter >>> >>> Hi, Peter, >>> >>> It is not exactly but very close to what you ask about. Below you = will find a function along with its description. I use it to digitalize = functions only available as curves on graphics, like taken from images. = This might be what you have in mind. To try it just copy-paste any image = into Mathematica, give it a name and apply the copyCurve function to it. = Then act as it is described below. As the result you will get a list of = points coordinates. >>> >>> Have fun, Alexei >>> >>> >>> >>> Description >>> >>> The function copyCurve enables one to get the coordinates of curve = points from a plot found on an image and memorises them in a list = entitled ?listOfPoints? >>> Parameters: >>> >>> image is any image. It should have Head=Image, but may be also a = Graphics object, since no specific functions of image have been used. I = typically wrap it in Image[] statement. >>> >>> Controls: >>> >>> The Checkbox ?whiteLocatorRing? defines, if the locators are shown = by a single color ring (unchecked), or with two rings, the outer having = a color defined by the ColorSlider (see below), the innder being white. = This may be helpful, if working with a too dark image. >>> >>> size controls the size of the image. The default value is 450. This = slider is used to adjust the size to the one to enable the most = comfortable work with the image plot. >>> >>> opacity controls the opacity of the line connecting the locators >>> >>> thickness controls the thickness of the double ring that forms each = locator. >>> >>> lineThickness controls the thickness of the line connecting the = locators >>> >>> color is the color slider that controls the color of the outer ring = forming the locator and the line connecting them. The inned locator ring = is always white. >>> >>> radius controls the radius of the locators. >>> >>> InputFields: should be supplied by the reference points x1 and x2 at = the axis x, as well as y1 and y2 at the axis y. >>> >>> Buttons: The buttons ?Memorize scale X? and ?Memorize scale Y? = should be pressed after the first two locators are placed on the = corresponding reference points (presumably, located at the x or y axes). = Upon pressing the reference points are memorized. The button ?Make list = of the curve points? should be pressed at the end of the session. Upon = its pressing the actual list of points representing the points of the = curve is assigned to the global variable ?listOfPoints? >>> >>> >>> Operation: >>> Step 1: Execute the function with the name of the image containing = the curve to be digitalized. >>> >>> Step 2: Enter the reference points at the plot axes into the input = fields. Press Enter. >>> >>> Step3: Alt+Click on the point with x-coordinate x1. This brings up = the first locator visible as a circle. Alt+Click on that with x2 which = gives rise to the second locator. Adjust the locators, if necessary. = Press the button ?Memorize scale X?. >>> >>> Step 4: Move the two already existing locators to the points with = the coordinates y1 and y2. Press the button ?Memorize scale Y?. Now the = both scales are captured. >>> >>> Step 5: Move the two already existing locators to the first two = points of the curve to be captured. Alt+Click on other points of the = curve. Each Alt+Click will generate an additional locator. Adjust = locators, if necessary. To remove, Alt+Click on unnecessary locators. >>> >>> Step 6: Press the button ?Make the list...?. This assigns the = captured list to the variable ?listOfPoints?. Done. >>> >>> The ?listOfPoints? is a global variable. It can be addressed = everywhere in the notebook. >>> >>> The function copyCurve >>> >>> Clear[copyCurve]; >>> >>> copyCurve[image_] := >>> >>> Manipulate[ >>> DynamicModule[{pts = {}, x1 = Null, x2 = Null, y1 = Null, >>> y2 = Null, X1, X2, Y1, Y2, \[CapitalDelta]X, \[CapitalDelta]Y, = g, >>> myRound}, >>> >>> myRound[x_] := Round[1000.*x]/1000. // N; >>> >>> (* Begins the column with all the content of the manipulate *) >>> Column[{ >>> (* Begin LocatorPane*) >>> Dynamic@LocatorPane[Union[Dynamic[pts]], >>> Dynamic@ >>> Show[{ReplacePart[image, {4, 2} -> size], >>> Graphics[{color, AbsoluteThickness[lineThickness], >>> Opacity[opacity], Line[Union[pts]]}] >>> }], LocatorAutoCreate -> True, >>> (* Begin Locator appearance *) >>> Appearance -> If[whiteLocatorRing, >>> >>> Graphics[{{color, AbsoluteThickness[thickness], >>> Circle[{0, 0}, radius + thickness/2]}, {White, >>> AbsoluteThickness[thickness], Circle[{0, 0}, radius]}}, >>> ImageSize -> 10] >>> , >>> Graphics[{{color, AbsoluteThickness[thickness], >>> Circle[{0, 0}, radius + thickness/2]}}, >>> ImageSize -> 10]](* End Locator appearance *) >>> ],(* End LocatorPane*) >>> >>> (* Begin of the block of InputFields *) >>> , Row[{ Style["\!\(\*SubscriptBox[\(x\), \(1\)]\):"], >>> InputField[Dynamic[x1], >>> FieldHint -> "Type \!\(\*SubscriptBox[\(x\), \(1\)]\)", >>> FieldSize -> 7, FieldHintStyle -> {Red}], >>> Spacer[20], Style[" \!\(\*SubscriptBox[\(y\), \(1\)]\):"], >>> InputField[Dynamic[y1], >>> FieldHint -> "Type \!\(\*SubscriptBox[\(y\), \(1\)]\)", >>> FieldSize -> 7, FieldHintStyle -> {Red}] >>> }], >>> Row[{ Style["\!\(\*SubscriptBox[\(x\), \(2\)]\):"], >>> InputField[Dynamic[x2], >>> FieldHint -> "Type \!\(\*SubscriptBox[\(x\), \(2\)]\)", >>> FieldSize -> 7, FieldHintStyle -> {Red}], >>> Spacer[20], Style[" \!\(\*SubscriptBox[\(y\), \(2\)]\):"], >>> InputField[Dynamic[y2], >>> FieldHint -> >>> "Type \!\(\*SubscriptBox[\(y\), \(2\)]\)+Enter", >>> FieldSize -> 7, FieldHintStyle -> {Red}] >>> }], >>> (* End of the block of InputFields *) >>> (* Begin the buttons row *) >>> Row[{Spacer[15], >>> (* Begin button "Memorize scale X" *) >>> Button["Memorize scale X", >>> X1 = Min[Transpose[myRound /@ Union[pts]][[1]]]; >>> X2 = Max[Transpose[myRound /@ Union[pts]][[1]]]; >>> \[CapitalDelta]X = X2 - X1; >>> ],(* End of button "Memorize scale X" *) >>> Spacer[70], >>> (* Begin button "Memorize scale Y" *) >>> Button["Memorize scale Y", >>> Y1 = Min[Transpose[myRound /@ Union[pts]][[2]]]; >>> Y2 = Max[Transpose[myRound /@ Union[pts]][[2]]]; >>> \[CapitalDelta]Y = Y2 - Y1; >>> ](* End of button "Memorize scale Y" *) >>> >>> >>> }],(* End the buttons row *) >>> Spacer[0], >>> >>> (* Begin button "Make the list of the curve's points" *) >>> Button[Style["Make the list of the curve's points" , Bold], >>> g[{a_, b_}] := {(x1*X2 - x2*X1)/\[CapitalDelta]X + >>> a/\[CapitalDelta]X*Abs[x2 - x1], ( >>> y1*Y2 - y2*Y1)/\[CapitalDelta]Y + >>> b/\[CapitalDelta]Y*Abs[y2 - y1]}; >>> Clear[listOfPoints]; >>> listOfPoints = Map[myRound, Map[g, pts]] >>> ](* End of button "Make the list..." *) >>> >>> }, Alignment -> Center](* >>> End of column with all the content of the manipulate *) >>> ],(* End of the DynamicModule *) >>> >>> (* The massive of sliders begins *) >>> Column[{Row[{Control[{whiteLocatorRing, {True, False}}], >>> Spacer[50]}], >>> Row[{Spacer[32.35], Control[{{size, 450}, 300, 800}], >>> Spacer[38.5`], Control[{{opacity, 0.5}, 0, 1}]}], >>> Row[{Spacer[10.], Control[{{thickness, 1}, 0.5, 5}], >>> Spacer[13.65], Control[{{lineThickness, 1}, 0, 10}] }], >>> Row[{Spacer[22.8], Control[{color, Red}], Spacer[59.3], >>> Control[{{radius, 0.5}, 0, 3}]}] >>> }, Alignment -> Center],(* The massive of sliders ends *) >>> >>> (* Definitions of sliders *) >>> ControlType -> {Checkbox, Slider, Slider, Slider, Slider, >>> ColorSlider, Slider}, >>> ControlPlacement -> Top, SaveDefinitions -> True >>> ]; >>> (* End of the function *) >>> >>> >>> Alexei BOULBITCH, Dr., habil. >>> IEE S.A. >>> ZAE Weiergewan, >>> 11, rue Edmond Reuter, >>> L-5326 Contern, LUXEMBOURG >>> >>> Office phone : +352-2454-2566 >>> Office fax: +352-2454-3566 >>> mobile phone: +49 151 52 40 66 44 >>> >>> e-mail: alexei.boulbitch at iee.lu >> >> --- >> Murray Eisenberg = murray at math.umass.edu >> Mathematics & Statistics Dept. >> Lederle Graduate Research Tower phone 413 549-1020 (H) >> University of Massachusetts 413 = 545-2838 (W) >> 710 North Pleasant Street fax 413 545-1801 >> Amherst, MA 01003-9305 >> >> >> >> >> >> > > --- > Murray Eisenberg = murray at math.umass.edu > Mathematics & Statistics Dept. > Lederle Graduate Research Tower phone 413 549-1020 (H) > University of Massachusetts 413 545-2838 = (W) > 710 North Pleasant Street fax 413 545-1801 > Amherst, MA 01003-9305 > > > > > --- Murray Eisenberg = murray at math.umass.edu Mathematics & Statistics Dept. Lederle Graduate Research Tower phone 413 549-1020 (H) University of Massachusetts 413 545-2838 = (W) 710 North Pleasant Street fax 413 545-1801 Amherst, MA 01003-9305

**References**:**Re: Cursor position on images***From:*Alexei Boulbitch <Alexei.Boulbitch@iee.lu>

**Re: How get Alt+Click to work in Mathematica in OS X?**

**Manipulate: Tracking symbols which are not stated explicitly**

**Re: Cursor position on images**

**Re: Cursor position on images**