editable rectangles

[parmar ranjit]

Dear friends,
Good Morning...
I am using LINUX with Qt 4.
DETAILS: I have black & white scanned copy of text document. Further I have filtered and even binarized that image ( jpg or tiff) Now I am to draw editable rectangle on words. I have been able to draw RED rectangle using SETPIXEL( ) on an IMAGE as shown in attachment 1. For that purpose i tried a lot with function like DRAWRECT but I could not.
So I have regenerated the whole image keeping black pixel as black & white as white in new image AND then draw RED rectangle (given coordinate) with two FOR loops using setpixel().(here in attachment i have shown non filterd image to feel background image)


PROBLEM: How to edit that rectangle which has been drawn on image ? I mean to say how will I be able to change the dimensions of rectangle using mouse event? It is some thing like we do adjust the hor. & vertical lines in table in MS WORD with mouse.
In short how to change rectangle in attch1 to look like in attch2?

Thanx
Ranjit Parmar
INDIA

[jpn]

As long as the rectangle should remain editable you might not want to add that rectangle to the image itself but just render it over the image on screen.

[yosefm]

I would load the base image in a QGraphicsScene, then I can create rectangles without changing the underlying image. Then you display the scene using a QGraphicsView widget. Selecting and drag-and-drop are built into these two classes.

[parmar ranjit]

Thnx for reply,
ya
You are right. Even when I have been able to draw perfectly rectangles on image using setPixel( ) at specifed coordinates of image, but yet it will not be possible to DRAG or EDIT those rectangles because they are the part of the image at pixel level.

Since I am new to Qt, will you please elaborate in little more detail using some simple code :
How to form editable rectangle at given coordinates on image?
I think then only it will be possible to DRAG it using MOUSE.

Waiting eagerly 4 reply
Ranjit Parmar: