Identifying the model in the image

Index

Identifying the model in the image

Loading the image file

We can load a jpg or bitmap image onto the application by using the Load Image menu option. This option is available after we have opened a mold file on which the image has to be applied (see mold options). The loaded image will then be displayed in the right frame.

Identifying the background region

We have to mark the background regions (regions other than those of the model) in the image before we click on the apply to mold option to process the image. The following two figures shows the original image and the image after marking out the background.

In the left image, the different shades of blue consist of the background, while the rest part (mostly black) is the model. All the background regions are shown as marked in the right image.

Two options are available for marking the background.

Setting a background screen
This is the preferred method as it is fast and convenient. While taking the photograph of the model, we can put a green, blue or red screen behind it to serve as the background. While selecting the screen, we should also make sure that no part of the model has matching colors with that of the screen (for e.g. if we are choosing a green screen, then no parts of the model should be of green color). See set background screen dialog for details.
Marking background colors
Background can also be set by clicking and identifying the parts of the image other than the model. Two types of markers are available for this purpose. The color marker is selected as default. We can use the appropriate toolbar button or the Menu option 'EditImage->Change Marker Type' to switch between the two types.
- Region Marker
  After selecting this type of marker, we can move the mouse to the background regions and click on them to set them as background. We can increase the marker size by using the 'EditImage->Change Marker Size' option. However, marking backgrounds in this way is a time taking process and should be used only when the second option does not work out.
- Color Marker
  By using this type of marker, we can mark the colors in the image which are depicting the background. Once we select a particular color as background, all the regions with the same color in the entire image is marked as background.
  When this marker is in use, the color of the clicked spot is selected and a dialog box opens. Using the options on this dialog, we can specify a range of colors to be marked. For e.g. we could specify a range in which the specified color and all it's darker shades should be marked. Similarly we could choose all lighter shades of the same color. See the documentation on set background color dialog for more details.
By keeping an approriate background while taking the photograph and using the second type of marker, we can easily mark the entire background in one or two steps. For e.g. in the above photograph, we see that the model is black (the darkest) while the background consists of different shades of blue. By selecting the darkest shade of blue and asking the application to mark that color as well as all lighter colors, we can mark the entire background in one step. Thus maintaining sharp contrast between the color of the model and the background could speed up this process. The importance of a good quality camera can also be seen here as the improper variations in color would be less if we use a good camera.

If by mistake, some parts of the actual model is also marked on using one of the above options, we can use the Undo (Ctrl+Z) option to undo the step.

Non-permissible model color

The grey color with RGB components of (R=200, G=200, B=200) is used to mark the background. So if any part of the model has this particular color, then that part would be recognised as background by default, thus giving erroneous results.
If your system is set to true colors, then the background that you are seeing right here depicts the same color.