Tutorial: Direct Stereo Pairs

GUG Soft Home 3D Gugle Home
Attention if you cannot see all the images and movies on this page you will need to "Refresh" it. Right-click with the mouse button and select"Refresh".

Choose a language to translate this page	Search in 3D Gugle User's guide

For more detailed information regarding 2D to 3D conversion, see the following 3D Gugle tutorials :

    Direct Anaglyph               To convert an image to anaglyph

    Direct Depth Map             To convert an image to a depth map
    Direct Layers,                   To convert an image using Layers
    Box                                  To extract the Layers from "By Points" method and more...
    Layers Assembly               To create a stereo image from layers

    Free deformation              To create a free virtual depth or to make stereo deformations
    Sphere LAB                      To create a spherical virtual depth or to make stereo deformations
    Depth LAB                        To create a virtual perspective or to make stereo deformations

    Stereo Analysis                 To verify the quality of the 3D conversion

    Paint LAB                          To retouch or to clone areas
    Combine LAB                     To sum two images

    Write LAB                        To add normal or stereoscopic text to your images

    Frame Shop Lab                 To add a normal or stereoscopic frame

    Luminance LAB                   To control the general colour-depth and to setup the colours for printing

    Emboss Depth Emphasise     To add form and modeling to images

    Jpeg Analysis                   To correctly save an image using the JPEG format

After opening an image that you wish to convert to 3D, select "2D to 3D/Direct Stereo Pairs".

In the new environment of "Direct Stereo Pairs" the preceding menus are replaced with other menus relevant to the conversion job.

Perspective control

With "Perspective Control" it is possible to create deformations in order to correct errors or to create special effects.

Even after a deformation is applied by pressing 'OK' in the "Perspective dialogue", you can still alter it before moving to the next plane.

To Undo the previous deformation, use mouse left-click, to Redo it use mouse right-click.

Auto 3D
"Auto 3D" serves to emphasise the relief of small details for which the manual procedure would be impossible or tedious.

Auto 3D's algorithm operates on the luminance value.
In other words, it tries to imitate the human eye by putting greater relief into the lighter objects.

Although the Auto 3D effect is applied to the entire image, it is easy to cancel it in selected areas by moving the mouse with the left key depressed.
If you make a mistake, restore by moving the mouse with the right key depressed.

Save Project (Work)

"Save Project" saves the current project together with all the necessary parameters to continue the work from the same state at a later time.

Files with the extension *.3dd can normally be opened from the menu: "File/Open Image", with a drag-and-drop method or by making a double click on the name from Window's "Resource Explorer".

When you open a "Project" file directly, you enter the "Direct Anaglyph" environment in exactly the same state as when you left it.

Fixing
"Fixing" resets the counters and memory and 'freezes' the image, prohibiting any further change.

Fixing is an important function as it serves to preserve the image for final retouching and completion.

Restart
"Restart" cancels all the performed operations, restoring the memory and image to their original state.

If "Fixing" has been previously applied, "Restart" restores the image to how it was at the time of the last fixing.

Exit
"Exit" is the only way to leave "Direct Stereo Pairs", it is advisable that you first "Save Project".

Before returning to the ordinary environment of "3D Gugle", "Direct Stereo Pairs" asks if you want to save the changes.

If you answer "Yes", the Stereo image is recopied to the main window and in this way you can save or correct with the other 3D Gugle tools.

If you answer "No", the image will reappear in the main window as it was before conversion.

The menu: "Trace" contains the options to change the size of the chisel, to activate the Box and to use the recorder.

"Numerical menu 2-250" changes the diameter (of a circular chisel) or the side (of a square chisel).

The use of the function keys is preferable because it allows for rapid change without removing the chisel from the area being worked-on.

"Box" The "Box" tool is very important and provides two functions, the first acts as a chisel but with the ability to operate on large areas, the second defines a visual reference guide that helps you avoid unnecessary retouching work.

The Box is enabled by pressing the "Space Bar" key and cancelled pressing the "c (Cancel)" key.

"Centre Box" When the Box is shown this menù is active and it positions the Box to the centre of the window.

This function is essential when the image area is large because it allows you to immediately recall the Box into the work area without having to seek it by moving the scroll bars.

Trace: "Trace Type" From this menu it is possible to choose a circular or square chisel.

The circular chisel is the most useful in the majority cases but for the straight lines it is essential to use the square form.

"Record" The recorder is an important option that allows the job to be simplified.

The recorder memorises all the actions performed with the mouse or with the Box and repeats them when pressing the "E" key (Execute) .

"Record Start" Start recording
"Record Stop" or F12 Stop recording
"Record Execute" or key "E" Applies the recording

Menu View
With this menu the work area can be magnified in order to work with greater precision on small details.

If the option "Window" is activated the image is automatically resized when you change the dimension of the main window.

"New Window"
The menu opens a new window with automatic image resizing that contains a copy of the main image.
This window can be useful when the images are very large to provide a high-quality view of a small area .

Ideally, this window should be located on a second monitor if your graphics-card supports dual monitors.

"Synchro Window"
This menu contains the functions required to see the preview during the conversion work.
This function is the "Synchro Window".
If you select "Synchro Window", a new window will appear synchronised with the main window.
This window provides a real time preview.

For ease of working, the synchronised window also has some associated menus.
For further information regarding the synchronised window see "Procedure"

"Synchro Window", "Menu: File"
With this menu you can open a new image in the window.

Normally when you activate this type of window, the window contains a copy of the main image.

"Synchro Window", "Menu: Shift"
With this menu you can decide what movements to allow the window contents.
The image of this window can be dragged with the mouse.
When the mouse moves on this window, the mouse-cursor changes and indicates what movements are possible.

"Horizontal" you can move the image only in the horizontal direction,
"Vertical" you can move the image only in the vertical direction,
"Free" you can move the image in any direction,
"Reset Shift" With this menu you reset the image to its initial position,

"Synchro Window", "Menu: Window"
This menu allows for lining-up the window synchronised with the main window

"Vertical Align" The two windows are arranged vertically, one above the other
"Tiled Main Right" The two windows are arranged side-by-side fitted to the screen width. The main Window is on the right.
This option allow for cross-eyed previewing.
"Tiled Main Left" The two windows are arranged side-by-side fitted to the screen width. The main Window is on the left.
This option allow for parallel-eyed previewing.

Special Menu (Mouse and Keyboard)

Mouse: Mouse: The chisel is enabled by pressing the left button and cancelled (restore) by pressing the right button.
This way of operating is perfectly natural and learned in the blink of an eye.

Box: The Box operates like chisels but it works by pressing the spacebar and it restores by pressing the "c" key.

Key "Z": The "Z" key, if pressed, highlights the area of the job at the current depth, it returns to the normal state by pressing "Z" or making a click on the image with the mouse.

The work performed at the current depth is visible as an area of intense colour and the remainder is displayed in the complementary colours as in the figure below :

Menu: "<-": Pressing this pushes the perspective planes backwards, if you observe the image with a cross-eye method it will appear more distant

Menu "R=n": This menu is inactive and serves only to indicate which perspective level you are currently at.
The menu indicates out (negative) or in (positive) with respect to the reference depth level.

Menu: "+>": Pressing this pushes the perspective planes forward, if you observe the image cross-eyed it will appear nearer.

Definitions

1) The term "graphic object" denotes a part of the image that represents an identifiable feature.
For instance the armchair, the woman, the book, etc. are defined graphic objects.

2) The expression to "paint with the mouse" a graphic object refers to the whole surface of the object including the shift area.
The shift area is the area that becomes visible to the right or left of the object when clicking "<- " or " +>".
Try to avoid wandering outside the shift area or touching other graphic objects that have already been worked-on.

In the image below the case of an anaglyph, in the stereo image the problem is exactly the same and you have to work the left area or the left contour.

3) When it says "work only to the left area" or to the left contour this means the real area (contour) of the left side, as shown in red below.
Please to see also "left contour".

We will now proceed with a detailed description of an example conversion from a normal image to a three-dimensional image.

Having finished working at one level, you move to the next level and execute the same actions.

To use this image, right-click with the mouse on the image below, select "Save with name" and then select *.bmp extension.

After this Save operation, select 3D Gugle's "File/Open Image" to load the image that you have just saved and then select "2D to 3D/Direct Stereo Pairs".

Attention, the method that will be described is not the best way to make high-quality stereo, it is just a simple description of the main steps so that you can understand the procedure.

Graphic artists experienced in the art of the conversion have their own methods or improvements derived from experience.

3D Gugle is designed to allow the maximum operational flexibility and has tools with which it is possible to make a lot of corrective actions and other preparations prior to conversion, these operations can not only speed-up the work but improve the quality of the result.

Many artists also use some hybrid techniques based on direct conversion but also integrated with Layers, these operations are relatively complex and require a deep knowledge of 3D Gugle's capabilities.

1) Step
Select: "2D to 3D/Direct Stereo Pairs" to enter the Stereo Pairs conversion Lab.
Select "View/Synchro Window"
Select "Synchro Window/Window" and "Tiled Main Right" if you want a cross-eyed preview or "Tiled Main Left" for a parallel-eyed preview.

2) Step
You have to imagine that you are viewing the photo from above and divide it into depth-planes from near to far, as many as you like.
The quality of the final result depends on the number of planes that you use.

In the figure below, the depth planes are represented by the horizontal blue lines.

Attention, the seven planes represented in the figure are just an example to illustrate the procedure, in the example that follows there are more than seven planes

3) Step
When you start the conversion work, you are at reference depth plane Zero. (P=0)
This plane does not require any work and represents the area most distant to us.

Now, to start the conversion work, click "<- " and you move to the nearer plane -1.

To work on the objects, paint them with the mouse left-button depressed and, in case of error, restore with the mouse right button

The worked areas are shown in an intense blue color.

When you paint with the mouse you have to be careful not to wander into areas that belong to the preceding plane, (the plane that you have already worked on).

If you draw in areas that belong to the following plane, that is not a problem, (the following plane is the next plane that you will be working on).

This is a great advantage because it allows you to work quickly while concentrating on a small part of the image.

Remember:
1) to change the diameter of the chisel you can use the keys function from F1 to F10.
2) to see the extent of the worked area, press "z"

4) Step
Click "<- " (P = -2) to go to the depth plane nearer to you.
In this new depth plane, paint all zones that are represented in blue.

At each of the above steps, you click "<- " to go to a depth plane nearer to you.
These four clicks are performed without painting in order to introduce depth between the bridge and the train window.
It is important to understand this basic 3D Gugle concept..

These dark lines are remnants of the graphic objects that you have moved, but do not worry too much about these because they are easy to remove, (after conversion is completed), with the "Paint Lab" section.
The left part of the carriage is not the most distant interior part but has been worked first in order to minimise the dark line remnants.
In the next step, you will start to work on the most distant part and subsequently you will rework the part of window just worked-on.

10) Step
Click "<- " ..and continue the work.
Observe that the hat has been worked in the left part, this is necessary because the hat reenters an area already worked.

The function is explained in the section "Direct Anaglyph" in this help document.

With this step the preliminary work is completed.
You can complete this work in a few minutes.

Remember, at this point, save your job before continuing.
To save use "Option/Save Work"

Before continuing, you have to observe (carefully) your image to detect all the errors.
The image used in this example actually contains many errors but fortunately, with 3D Gugle, they are not a problem and are easily removed.

In the image below, the main errors are underlined, the points with little depth are marked in red , those with excessive depth in white.

To correct the errors, first you fix the image. To do this, select "Option/Fixing".

Now, if you want to increase depth, you click "<-" , if you want to decrease use "+>"

Before continuing with errors correction, it is necessary to clean the entire image with "Paint Lab".
To exit from "Stereo pairs" Lab, select "Option/Exit" and then select "Yes" to save the changes.

Do not close the "Synchro Window", this window helps you observe, in real time, the effectiveness of your cleaning actions.

To use the "Paint" Lab, please to see the "Paint" section in this help document.

Normally, to correct the stereo pair image you can use two functions: "All colours" or "Clone".
These functions are in the menu: "Mode".

After the cleaning action, you exit from Paint Lab and return to "Direct stereo Lab".

After the cleaning action, this is the result.

In this step you refine and complete your work.
It is necessary to zoom your image to 200-300 % and to use a small chisel.

Remember, if you want to increase depth , click "<-", if you want to decrease click "+>".
Generally, the positive value (P=+10) decreases and the negative value (P=-1) increases depth.

For further information regarding 2D >3D conversion please consult the section: "Direct Anaglyph" in the User's guide of 3D Gugle