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VLBV User Manual

Copyright 2013-2021, Artwork Conversion Software, Inc.


Table of Contents

Introduction

User Interface

   File Pulldown
   View Pulldown
   Preferences
   Help
   Toolbar

   Measuring with the Ruler

   Pan & Zoom with Mouse/Keyboard Controls

Appendices

   Installation


Introduction

VLBV (Very Large Bitmap Viewer) was developed by Artwork to solve a problem we had in testing our high resolution rasterizers. We needed a viewer that could handle GByte TIF monochrome (BW) files - tools such as Photoshop and other bitmap programs could not handle such large files.

We also needed a viewer that could handle very large monochrome BMP files - something that most Windows tools have problems with due to their use of libraries that are limited to 32 bit memory operations.

We finally wrote our own monochrome bitmap viewer designed specifically to handle these large files:



User Interface

Drop Down Menu

The VLBV drop down menu items

File
  Open
  Extract
  Layers
  File Info
  Recent Files
  Exit

View
  Home
  Redraw
  Zoom In
  Zoom Out
  Pan
  Previous View
  Next View
  Inverse Mode
  Image Boundary
  Mirror in Y
  Image Offset

Preferences
  Load Mode
  Units
  Status Bar



Tools
  XOR Image Data
  Navigation Dialog





Help
  Web Page
  Help
  About
  License

vlbv main window


File

Open

Use this to get to the File Open dialog.

Open File Dialog

Supported File Types

TIFF

monochrome or grayscale. Compression: packbits for monochrome.

BMP

monochrome or grayscale. Compression: packbits for monochrome.

RAW

monochrome with no header. No compression. User must specify the bitmap width in pixels and the byte alignment.


enter the width of the image for RAW bitmaps

RAW LG

monochrome with custom header for LG, Korea

Orbotech

greyscale output by Orbotech AOI.

CCIT

compressed monochrome format

Extract

Extract opens a dialog that enables the user to define a window, define the output format and compression and greyscale settings and save the extracted window to disk. Details.

For greyscale details, please refere to this page: Converting Monochrome to Greyscale

The extract dialog window

Layers

The layers dialog can be used to load up to two additional layers. Each of the total of three possible layers can have its color defined and also a transparency defined. By doing so, a user can easily see differences between almost identical bitmaps easily.

There is an additional control to mirror a layer.

the VLBV Layer Dialog

Info

Opens a window that provides a summary of the image's properties. If more than one image is loaded then it reports the image on the "active" layer.

VLBV Info window reports the (active layer's) image header properties.


View

Home

Zooms the display to the full extents of the data. Shortcut Key = H or Home


Redraw

Forces a screen redraw. Shortcut Key = R


Zoom In

Zooms in the display by 2X. Focus shifts to the display; user must left click with the mouse. Shortcut Key = +

Better practice is to use the mouse center wheel and rotate away from user.


Zoom Out

Zooms Out the display by 2X. Focus shifts to the display where the user must left click with the mouse.

Better practice is to use the mouse center wheel and rotate towards the user.


Zoom Window

Enables the user to define a window (using the mouse) to zoom into. First hit the W key. Then use the mouse (left key down) and drag from upper left corner to lower right.


Pan

Switches to the pan tool and enables the user to pan by click/drag of the mouse. Better practice is to hold the mouse center wheel down while dragging the cursor.


Previous View

goes back to the "previous" display. (Several levels are cached so this is quite fast)


Next View

Only active if a previous view has been selected. Goes to the view stored after the current view. Cached; so very fast.



 

Preferences

Status Bar

If checked, a status bar across the bottom of the display will be visible. The coordinates of the cursor are updated. Measurement information is also presented in the status bar.

presence of the status bar controlled by preference setting.

Load Mode

Controls how VLBV loads the data for display.

Load Mode controls how VLBV reads the bitmap data.


Tools

XOR Image Data

Opens a dialog that enables the user to perform an XOR operation on two layers (an image file per layer) and then returns a coordinate list of differences. The user can then open the Navigation Dialog and click on each entry in the list to zoom in on the location of the difference. Intended for finding very small differences in large bitmaps. Details can be found on this page: XOR Bitmap Comparison.

Navigation Dialog

The Navigation dialog relies on the results created by an XOR operation. It enables the user to click on any difference coordinate reported by XOR and to either zoom into the region about that difference or to maintain the current display window and highlight the location of the difference.

Sort by X Y - sorts the error coordinate list either by increasing X or increasing Y.

Preserve View - when checked, the current display window remains constant and the error difference location is highlighted. If not checked the display zooms in to the location of the error difference.

Show All Markers - displays all of the markers in the display window.

Margin - when in zoom mode, this determines the amount of pixels that are shown in each direction surrounding the difference coordinate.

Marker Color - sets the marker color.

Enable Filter - allows the user to set the minimum size error to appear in the list of error coordinates.

Filter Value - the value of the error in pixels

The navigation dialog for investigating XOR differences



 

Help

VLBitmapViewer Web Page ... — Opens the VLBV Web page at www.artwork.com

VLBitmapViewer Help... — Opens a local copy of the user manual (HTML)

About VLBitmapViewer — Displays the VLBV version and license information

License Information ... — displays license information

Help window


 

The VLBV Toolbar

VLBV has three separate tool bars. The functions are annotated below:

Standard

standard toolbar

Zoom to XY ...

Zoom to XY Toolbar

Layers ...

Layers Toolbar



 

Measuring with the Ruler

The ruler enables the user to measure the distance between two pixel locations. To use the ruler, first select it from the toolbar. The click on a location with the right mouse button. Now move the cursor to the second location and click with the left mouse button.

measurement example using the ruler

The X,Y and total distance between the two points will be displayed in the status bar.

To make a precise measurement over a large distance it is possible to zoom in, click with the left button, zoom out and then pan, then zoom in a again and make the second click with the right button.



 

Pan and Zoom using Mouse Controls

VLBV was designed to make pan and zoom quick and efficient using the mouse. We recommend a 3 button mouse with the middle button a scroll wheel.

Pan - hold the middle button down and move the mouse. The display will pan with the cursor.

Zoom In - Roll the scroll wheel (middle button) away from the user

Zoom Out - Roll the scroll whell (middle button) towards the user

a mouse with three buttons, the center one being a wheel is best for moving around inside of the VLBV display.