GSView 6.0 User’s Guide

1 Introduction GSView 6.0 is a user friendly viewer for displaying and/or manipulating PostScript, PDF, XPS, EPUB, CBZ, JPEG and PNG content. GSView 6.0 leverages the powerful viewing API of MuPDF along with the conversion capabilities of Ghostscript to provide both a fast and high quality on-screen viewing experience as well as a rich set of export and document conversion capabilities.

GSView 6.0 is unrelated to earlier versions of GSView, in that GSView 6.0 was designed from the ground-up by Artifex Software, which is the same team that developed Ghostscript and MuPDF. Previous versions of GSView were created and owned by Ghostgum Software. For the remainder of this document, GSView 6.0 will be referred to simply as GSView.

2 System Requirements GSView will work with any Windows OS that supports the .NET Framework 4.5. Examples include: Windows Vista SP2, Windows 7 SP1, Windows 8, Windows 8.1, Windows 10 and Windows 10 November Update. Server OS versions that are supported include: Windows Server 2008 SP2, Windows Server 2008 R2 SP1, Windows Server 2012 and Windows Server 2012 R2. The operating systems Windows 8, Windows 8.1, Windows 10, Windows Server 2012 and Windows Server 2012 R2 come preinstalled with at least the .NET Framework 4.5. Windows 7 and Vista may require the installation of .NET Framework 4.5. If it is required, the installation of the .NET Framework will be handled automatically by the GSView installer. GSView will work with 32-bit and 64-bit systems.

3 Installation You can download GSView from the website www.gsview.com. This download will provide an installer that you can launch and follow through with the usual set of steps one encounters when installing software. As mentioned above, depending upon your system and the software that you already have installed, the installer may perform the installation of the .NET Framework 4.5. It will be required for the computer to have internet access during that install.

On 64-bit computers, the application is installed in C:\Program Files\Artifex Software. On 32-bit computers, the application is installed in C:\Program Files (x86)\ Artifex Software. To uninstall GSView,

use the system’s control panel in Control Panel\All Control Panel Items\Programs and Features right -click the gsview entry and select Uninstall.

4 Launching Once installed, you can launch GSView in the same manner that you launch your other Windows applications. For example, you can launch it from the tiles in Windows 8.0, 8.1 or from the Start menu in other versions of Windows.

If you have a file type that GSView understands you can right click on that file and you should see an Open with menu that includes GSView as an option. If you have associated file types with GSView during the install (or later), double-clicking files of these types should launch GSView directly. File types that are associated with GSView should display GSView related icons such as these:

5 Shortcut Icon Usage Figure 1 displays an example where a PDF document is opened with GSView. Looking at the icons at the top,

starting from the left and working to the right, the folder icon will open the menu to open a new file. The disc icon will open a window for the save-as operation. Options for saving the output to different types is provided in the window. See Section 6.1 for details on save-as options. The printer icon will open the dialog for setting the print options. See Section 6.4 for details on this option. The blue arrows that follow next and the entry box relate to page navigation. The magnification +/-, the

box with the percent sign and the three icons relate to the sizing of the document. Selecting the thumb icon will result in thumbnails of the pages to be displayed in a region on the left side of

the main window. Selecting the contents icon will result in the contents information of the document (if contents exist in the source document) to be displayed in a region on the left side of the main window. Figure 2 displays an example document with the thumbnails and the document content

displayed. The chain icon will toggle off/on a highlight of hyperlinks that are present in the document. An example of highlighted hyperlinks is shown in Figure 3. The separations icon will result in the creation of a color-managed proofing display of the current document using the proofing capabilities of Ghostscript. Further details of this are provided in Section 8.1. Finally, text search capability is provided through the box following Search: and the left and right blue arrows. Selecting the arrows will go to the next page where the content is found, highlighting the words on that page. An example is shown in Figure 4.

Figure 1: Sample PDF document open with GSView

Figure 2: Document with thumbnails and page content information provided

Figure 3: Document with hyperlinks highlighted

Figure 4: Sample search for "color" in our document

6 File Menu Usage The menu options with GSView are as follows:

The File menu items will be discussed below. The Edit menu items will be discussed in Section 7. The view options simply allow another method to navigate forward and backward in the document. The Options menu items will be discussed in Section 8.

The File option displays the following:

Selecting Open will open a dialog box to open a new file. If a file is currently open, then a new instance of GSView will be opened with the file that was selected.

Save As… and the Export options are described in detail in Section 6.1.

Close will close the current document, leaving the instance of GSView running.

Info will provide a pop-up window that gives the path to the current document, the document type, the number of pages in the document and the current page number that is displayed.

Extract Selection is described in Section 6.2.

Advanced Conversions is described in Section 6.3.

Print will open a dialog box with some simple options. Further details are given in Section 6.4.

Show Messages will open a message box that displays the output information from Ghostscript when it performs file conversions including the distillation of Postscript to PDF and the conversion of PDF to XPS for the Windows print system. These messages may be useful if issues are encountered in the distillation of Postscript.

Open Recent will display a list of recently open files. Selecting an entry will open that file.

Exit will shut down the GSView application.

6.1 Save As.. Export Save As… and Export provides different interfaces to save the current document in a variety of formats. The Save As… option does this by providing a Save as type: option in the Windows Save As dialog box, while the File->Export selection provides a way to preselect the Save as type in the Windows Save As dialog box. For example, using Save As… in our sample document provides the following options:

The first 15 (PDF Files through Encapsulated Postscript) provide options for saving in a variety of vector-based document formats. The Export option provides a slightly different view organizing the options as a series of subset options as show here:

Going through the options in the list given in the Save As.. list:

PDF Files (*.pdf) will save the current file as a standard PDF file.

Linearized PDF (*pdf) will reorganize the data and save the PDF so that it can more easily be streamed allowing for faster viewing of the PDF content over the internet for example.

Expanded PDF (*.pdf) will decompress some of the drawing content objects in the PDF file. This is useful for developers who wish to manually manipulate PDF content.

PDF 1.3 (*.pdf) will save as a PDF file that adheres to the older 1.3 version of the PDF specification. The primary difference with this version over newer versions is that version 1.3 does not support transparency.

PDF/A-1 RGB through PDF/X-3 CMYK save the output as a PDF in a selected ISO standard. In general, PDF/A is used for archival purposes while PDF/X is used to facilitate graphics exchange primarily in printing applications. This document will not go through the details of the PDF/A and PDF/X standards. It is recommended that users who use this option read through the appropriate ISO specifications. PDF/X is formalized in ISO standards 15929 and 15930. PDF/A is formalized in ISO standard 19005. Saving in these standards does require strict specification of the colors in the document. As such, it is necessary to provide ICC profiles for the colors in the document. These are set using the menu selection Options->Output Intents. This will open a window as shown in Figure 5. From here you should select the ICC profiles that you want your source colors in the document to be tied to. Details about the ICC specification are provided at www.color.org.

PCL-XL (*.bin) will save the document in Hewlett Packard’s PCL-XL format appropriate for printing on printers that understand PCL content. PCL-XL

XPS (*.xps) will save the document in Microsoft’s XPS document format.

SVG (*.svg) will save the document in the XML-based svg format. This format is viewable by all modern web browsers.

Postscript (*.ps) will save the document in the PostScript format. See the Adobe specification for details on this format.

Encapsulated PostScript (*.eps) will save the document in the encapsulated PostScript format. The encapsulated PostScript format contains an image of the PostScript content as well as bounding box and other document structuring conventions to facilitate a preview of the content.

Figure 5: Output Intent Settings

The next three formats (TIFF, PNG and JPEG) will save the document pages as image files in the selected formats. Option windows for each of these will appear if they are selected. For example, if PNG is selected the dialog shown in Figure 6 will display. This allows one to embed an ICC profile with the PNG output as well as set the rendering resolution and the output color space. It is also possible to specify if certain object types should be anti-aliased during the rasterization process.

If the TIFF format is selected, the dialog shown in Figure 7 will be displayed. Here again we can select the ICC profile that we wish to specify that our content will be. In addition, we can select from a number of compression schemes, resolutions, color spaces and bit depths. As with the PNG options, we can specify if certain object types should be anti-aliased during the rasterization process.

Finally to round out the image formats, if the JPEG format is selected, the dialog shown in Figure 8 is displayed. Again we can select the ICC profile, the quality, the resolution, the color space as well as the anti-aliasing options.

Figure 6: PNG Save As /Export Options

Figure 7: TIFF Save As/Export Options

Figure 8: JPEG Save As/Export Options

The final three output formats of Text (*.txt), HTML (*.html) and XML (*.xml) provide different text formats that are extracted from the document.

6.2 Extract Selection Extract selection provides the capability to extract a small part of the content that exists on a document page and save it as a new PDF, PostScript or EPS file while maintaining the vector content of the original source. When File->Extract Selection is selected, the option for the output type will be displayed through the menu as shown in Figure 9. Selecting one of the options will bring up a new window with just the current page shown. An example is shown in Figure 10. Within this window, you can use the zoom buttons to adjust the resolution. To select your region of interest, use the left mouse button to select an anchor point, drag and release. An example is shown in Figure 11. Once the area of interest is selected, press OK on the menu to save the area in the format that was specified (PDF, PS or EPS). This will launch a dialog box to specify the output file name.

Figure 9: Extract selection options

Figure 10: Example selection window

Figure 11: Rectangular selection of area of interest to extract

6.3 Advanced Conversions The File->Advanced Conversions options provides a dialog box as shown in Figure 12. This control allows the user who is familiar with Ghostscript command line options the power to specify options when converting the current document with the Ghostscript engine. The output device is selected under the Devices options, the pages that you want to have converted are selected under the Pages options and special command line options can be specified in the GhostScript Options. For example, to specify a 600dpi resolution, you would add in the option –r600. The command line options for Ghostscript are too long to be included in this document. Details can be found at ghostscript.com/doc/current/Readme.htm. For certain output devices, the MuPDF library is used for performing the conversions instead of Ghostscript. Those are listed at the beginning of the list of devices and have a :MuPDF added to their device name. For raster output MuPDF devices (eg. pnm pwg), you should specify the output resolution in the MuPDF Resolution box.

Figure 12: Advanced Conversions Dialog Box

6.4 Print Dialog Box When the File->Print or the print icon is selected, the Print Dialog box will appear as shown in Figure 13. The options are self-intuitive. The properties button will bring up the printer specific controls. It should be noted that GSView converts the source documents to XPS content for the Microsoft print pipeline. Hence, when you do print you may see a progress bar as it performs the conversion (when the source document is not in XPS format).

Figure 13: Print Dialog

7 Edit Menu Options Selecting the Edit menu brings up the choices shown in Figure 14.

Figure 14: Edit Menu Options

7.1 Extract PDF Page When the Edit->Extract PDF Pages is selected, the dialog box show in Figure 15 is displayed.

Figure 15: Extract PDF Pages Dialog Box

This dialog enables the user to select and rearrange the pages within the PDF document. The page order can be reversed, only odds or only evens selected. Individual pages can be selected or added to your selections by pressing the control key while selecting the page. Using the control key and selecting pages that are already selected will removed those pages from your selections. The order of the pages can arranged by dragging the page numbers within the Pages box. Once you have selected the pages you want in your output file, simply press extract, which will launch a File Save dialog window.

7.2 Copy Page / Paste Page To The Edit->Copy Page selection will copy the current page in your document to the system’s clipboard. The resolution of the copy is the same as the current viewing resolution. Once you have selected this option you can then paste an image of the current page into other applications that accept images from the system’s clipboard.

The Paste Page To option will provide the opportunity to save the current page that you copied to the clip board to a number of different image formats. The formats are given in the menu option as shown below

Once a file type is selected, a File Save dialog window will appear.

7.3 Text Selection The options Edit->Select Text All, Edit->Deselect Text and Edit->Copy Text all deal with the selection of text within the document. Select Text All will select all the text in the document and the text will be highlighted with a blue overlay. Deselect Text will unselect all the text that has been selected in the document. Copy Text will copy the currently selected text to the system’s clipboard allowing the user to paste the text into other applications.

Text selection can also be performed using the left mouse button to directly select the text in the document. Using the right button on the mouse in the document, will bring up a context menu that provides additional options for text selection as shown below:

This provides additional control in that you can rapidly select a line of text, a block of text or all the text on the current page.

8 Options Menu The Options menu selection provides a list shown here:

The Options->Signatures selection provides some management of digital signature certificates. This is currently still under development.

The Options->Output Intents selection will open the output intents dialog as already discussed in Section 6.1. Its purpose is in the use of creating PDF/X and PDF/A content.

The Options->Proof Settings is described in detail in Section 8.1.

Show Annotations is discussed in Section 8.2 and anti-aliasing is discussed in Section 8.3.

8.1 Proofing Settings The Options->Proof Settings is related to the proofing icon that was discussed earlier. When this option is selected, the dialog box shown in Figure 16 is displayed.

Figure 16: Proof Settings Dialog Box

The purpose of the proof creation is to display a color managed rendering of a page as it would appear on a specific printer at a set resolution. To achieve this, the user must specify an ICC profile for the print device, an ICC profile for the display, which is being used with GSView (Soft Proof Profile) and a

resolution. With those settings set, the user press OK, which will then cause the current page to be rendered with those settings. A new window will also open to display this content, since it is particular to those settings. In this way, it is possible to compare and contrast renderings at different resolutions and color settings. For example, consider the Altona Visual Test file (www.eci.org/en/projects/ats) rendered at 72dpi with the default SWOP CMYK printer profile and assuming that we are running GSView on a device that has a sRGB display. In that, case we would have an output as shown in Figure 17.

Figure 17: Altona Visual Test file rendered with SWOP CMYK and sRGB

If instead we selected our display profile to be a Wide Gamut RGB color space we end up with the output shown in Figure 18.

Figure 18: Altona Visual Test file rendered with SWOP CMYK and a Wide Gamut RGB profile

In this case, the colors are much more saturated due to the fact that those colors are not mapped into the much smaller sRGB gamut. Of course, the “proper” image is the one that displays correctly on your display and as such is dependent upon you having a characterized print and display system.

Note that there are some controls in the proofing window to navigate to other pages and adjust the zoom for the proofed page. The zoom in this case will not re-render the page as is done in the document view window of GSView. Instead the rendered resolution is fixed based upon the Proof Settings dialog box.

Individual color separations can be turned off and on by selecting the small triangle on the left of the window. For example, Figure 19 displays the Altona file with the black separation removed and Figure 20 displays the Altona file with only the orange separation displayed.

Figure 19: Altona Visual File without black separation

Figure 20: Altona Visual File with only the orange separation

8.2 Annotations The PDF format includes the ability to have annotations in the document. Examples of annotations include underlined or highlighted text. GSView supports the display of annotations and allows the user to control if they are displayed though the Options->Show Annotations selection. For example, Figure 21 displays a document page that has Show Annotations “on” for the left rendering and Show Annotations “off” for the right rendering.

Figure 21: Document page with and without annotations displayed

8.3 Anti-Aliasing In the world of rendering, anti-aliasing is a process to improve the low resolution rendering of text and graphic objects. Aliasing occurs when a signal with high frequency content is sampled at too low of a frequency rate (below the Nyquist rate). In the case of text, the high frequencies are the sharp edges that would have been drawn if we had infinite resolution. The low sampling rate results in the high signal frequencies being “aliased” to lower frequencies resulting in undesirable artifacts. The anti-aliasing process removes the high frequency components in the original signal. Sharp edges in the text for example are replaced with more gradual gray transitions. Different users may prefer different amounts of anti-aliasing when viewing certain documents. With GSView, you can adjust the amount of anti-aliasing that the rendering engine performs through Options->Anti-Aliasing. For example, Figure 22 displays text segments with different anti-aliasing settings. These images are blown up 3x to enable the reader to see the differences. The user is urged to try out different settings to set their own preference.

Figure 22: Example of anti-aliasing

9 Forms and Password Protection GSView supports the use of forms as well as interactive items that make use of Javascript. Form files that are changed will prompt the user for saving prior to exiting the application. The information that the user has entered will be stored in the document for later use.

Support also exists for the viewing of password protected PDF files.

10 Further Help For up-to-date versions of GSView, please visit www.gsview.com . Issues should be reported to the Bug Tracker bugs.ghostscript.com. Finally, feel free to visit the developers of GSView, MuPDF and Ghostscript in the #ghostscript channel on irc.freenode.net.

Copyright (c) 2016, Artifex Software Inc. All rights reserved.