Freeware Program for Converting Image Sequences to Flash Movie Loops

Transcription

1 Converting Image Sequences to Flash Movie Loops Computers Computers in Radiology Chun-Shan Yam 1 Yam CS Keywords: cine loop, freeware, movie clip, PowerPoint, Shockwave Flash DOI: /AJR Received May 14, 2007; accepted after revision July 16, Department of Radiology, Beth Israel Deaconess Medical Center and Harvard Medical School, WCC, Room 306, 330 Brookline Ave., Boston, MA. Address correspondence to C. S. Yam (csyam@caregroup.harvard.edu). WEB This is a Web exclusive article. AJR 2008; 190:W68 W X/08/1901 W68 American Roentgen Ray Society Freeware Program for Converting Image Sequences to Flash Movie Loops OBJECTIVE. This article provides a freeware program created for converting image sequences to Flash movie loops. CONCLUSION. Although Flash is a useful format for presenting dynamic data sets in PowerPoint compared with other movie clip formats (e.g., AVI), the associated cost of the required Flash application ($699) is a common concern for many academic radiologists. To address this issue, a freeware program for creating simple Flash movie loops from image sequences has been developed for this article. hockwave Flash (Adobe) is currently one of the most commonly S used multimedia formats for Webbased animations and applications. Because of its cross-platform compatibility and programmable interactivity, Flash is also a useful format for displaying dynamic data sets in radiology presentations. In particular, for PowerPoint presentations (Microsoft), the ability to embed movies makes Flash a more robust alternative compared with other movie clip formats such as AVI (Microsoft) and QuickTime (Apple) (i.e., as a solution to prevent the common issues of incompatible codecs and missing file links [1]). To help academic radiologists understand this new technology, basic introductions of Flash, practical demonstrations in creating Flash movie loops from image sequences, and techniques for embedding Flash files into PowerPoint were provided in a recent series of tutorial articles [1 3]. Unfortunately, Flash is not a freeware program. To create Flash movie loops, the Pro version of Flash must be purchased at a cost of $699 ($199 upgrade) [1]. According to feedback from AJR readers and reviewers, this associated cost is a common concern for many academic radiologists. Fortunately, the file format of Flash is nonproprietary, and it is available for program developers as open source [4]. As such, many third-party Flash programming tools are available on the Internet. A freeware program for creating simple Flash movie loops was developed for this article using these resources. This freeware program, Flash Movie Loop Creator (FML Creator, hereafter) is a stand-alone PC-based application that does not require any other third-party applications. It was developed, in part, from an opensource imaging utility, FreeImage, [5] using the Visual Basic (Visual Studio, Microsoft) language. Because this article focuses only on the use of FML Creator, details of Visual Basic programming will not be discussed. However, a list of the open-source utilities and components used for program development is described in Appendix 1. (Note: For advanced users, the Visual Basic source code can be requested from the corresponding author via .) A step-by-step demonstration for creating a Flash movie loop from a sequence of images is provided later in this article. To begin, users must first download the supplemental data files (Fig. S1), containing the installation file, sample images, and PowerPoint template. Downloading and Installing FML Creator Download the installation file setup.exe for the FML Creator from the supplemental folder (Fig. S1A). Double-click the file to start the installation (Fig. 1). Similar to installing other desktop applications, the default destination folder (i.e., the installation location) for FML Creator is the main folder: Program Files (i.e., C:\Program Files\Supplemental Data\the FML Creator\). However, users can change this location as needed (Fig. 1B). The FML Creator is launched from the Start menu (i.e., W68 AJR:190, January 2008

2 Converting Image Sequences to Flash Movie Loops Start Programs Supplemental Data FML Creator Launch FMLCreator.exe), but first, an image sequence must be prepared. Demonstration Image Preparation Because the purpose of the FML Creator is to create Flash movie loops from image sequences, users will need to prepare an image sequence for this tutorial. Detailed information for preparing digital images for radiology presentations has been discussed previously [6]. For this demonstration, a sample image sequence of a normal pancreatic CT study is provided as a self-extracted zipped file, A C Fig. 1 Installation of Adobe Shockwave Flash Movie Loop Creator. A D, Screen captures of freeware program Flash Movie Loop Creator show individual steps for program installation. Installation package was created using InstallShield Express (Macrovision). Installation files are in supplemental data files (Fig. S1). (InstallShield screen shots reprinted with permission from Macrovision) 50_images.exe, in the supplemental folder (Fig. S1B). After downloading the file, double-click on it to uncompress the images to a common location such as the desktop. Open the image folder 50_images and spot-check the images. There should be 50 JPEG images within this folder (i.e., CT01.jpg to CT50.jpg). Users can also use their own image sequences for this tutorial. The FML Creator supports a wide range of digital images including JPEG, bitmap, GIF, TIFF, PNG, etc. A list of the supported image formats is shown in Table 1. It is also important to note that the images must be labeled sequentially in alphanumeric order. Flash Movie Loop Creation Launch the FML Creator from the desktop Start menu. A three-step operation guide will first appear in the main window (Fig. 2A). This window is a simple drag-and-drop action of the source images. Step 1 Select all the image files (n = 50) from the downloaded folder 50_images.exe. This can be done by either using the computer mouse to highlight all the image files or choosing the Edit Select All function from the file menu. Then, drag the selected images into the FML Creator application window. Images will be displayed as thumbnails on the windows. Use the scroll bar on the right to view the images and ensure that all are loaded (Fig. 2B). B D AJR:190, January 2008 W69

3 TABLE 1: Image Formats Supported by Adobe Flash Movie Loop Creator Image Format File Extensions Description BMP.BMP Windows (Microsoft) or OS/2 (Apple) bitmap file CUT.CUT Dr. Halo (Media Cybernetics) DDS.DDS DirectDraw Surface (Microsoft) FAXG3.G3 Raw fax format CCITT G3 GIF.GIF Graphics interchange format HDR.HDR High dynamic range ICO.ICO Windows (Microsoft) Icon IFF.IFF,.LBM Amiga IFF JNG.JNG JPEG network graphics JPEG.JPG,.JIF,.JPEG,.JPE Independent JPEG Group KOALA.KOA Commodore 64 Koala format (Apple) MNG.MNG Multiple network graphics PBM.PBM Portable bitmap (ASCII) PBMRAW.PBM Portable bitmap (BINARY) PCD.PCD Kodak PhotoCD PCX.PCX Zsoft Paintbrush PCX bitmap format PGM.PGM Portable graymap (ASCII) PGMRAW.PGM Portable graymap (BINARY) PNG.PNG Portable network graphics PPM.PPM Portable pixel map (ASCII) PPMRAW.PPM Portable pixel map (BINARY) PSD.PSD Adobe Photoshop RAS.RAS Sun Rasterfile SGI.SGI Silicon Graphics SGI image format TARGA.TGA,.TARGA Truevision Targa file format TIFF.TIF,.TIFF Tagged image file format WBMP.WBMP Wireless bitmap XBM.XBM X11 bitmap format XPM.XPM X11 pixmap format Note Adapted from [11]. Step 2 Enter the frame rate for the Flash movie loop (Fig. 2B). A default frame rate of 15 frames per second is most appropriate for presenting dynamic data sets of many CT studies. However, users can change this setting as needed [1]. Step 3 Click on the Create Movie button. A dialog box will appear prompting for the destination and filename of the Flash movie (Fig. 2C). For this tutorial, a Flash movie file CT_Panc.swf (1.55 MB) is created on the desktop. The file extension for Flash movies must be.swf for use in PowerPoint. Viewing Flash Movie Loops Similar to other Windows controls (e.g., ActiveX components), Flash movies must be displayed as an object within other applications such as a Web browser or a PowerPoint slide [1]. The easiest way to examine the Flash movie loop is to drag the file into a Web browser. In other words, launch a Web browser such as Internet Explorer (Microsoft), and then drag the Flash movie into the browser window. In Internet Explorer, the movie playback controls (e.g., Play, Stop, Forward, etc.) are available at the drop-down menu (i.e., right-mouse click) of the Flash object (Fig. 2D). Inserting Flash Movie Loops into PowerPoint As discussed in a previous article [2], Flash movies must be imported into PowerPoint slides as Control Objects, and the associated processes (i.e., the standard approach suggested by Microsoft) for doing so are quite cumbersome. To streamline this labor-inten- sive task, a PowerPoint template with a macro was created in a previous article [2]. This PowerPoint template, SWF_Into_PPT.ppt (29.0 KB), can be found in the supplemental data for this article (Fig. S1C). Step-by-step instructions for using this template are presented in Table 2. Limitations This freeware is aimed at creating simple Flash movie loops for presenting dynamic data sets in PowerPoint as an alternative to other movie clip formats, such as AVI, Quick- Time (Apple), and MPEG. It is, however, not designed for developing other interactive applications that require the programming of Action-Script (Adobe) [7]. For developing interactive applications, the full version of Flash (or Flash Pro) must be purchased. For instance, creating Flash movies with image scrolling requires Flash Pro. Step-by-step instructions for creating scrollable Flash movies using a template were presented in a previous article [3]. It is important to note that this freeware does not support movie clip formats such as AVI and QuickTime as the input source. Movie clips must first be extracted as individual images using other desktop applications such as QuickTime Pro (Apple, $29) [8]. Also, DICOM images are not supported. A method for converting DICOM files into compatible formats (e.g., JPEG) has been discussed previously [9]. Alternatively, using DICOM images directly in PowerPoint has also been discussed [10]. Discussion The cross-platform compatibility and file-embedding features of Flash make it a robust tool for presenting dynamic data sets in PowerPoint; however, Flash is a complex program requiring relatively high levels of operator skill and programming knowledge to access full functionality. The cost is also a major concern for academic radiologists who most likely will not use the more complex Flash functions. This article provides an easy-to-use freeware program for converting image sequences into Flash movie loops for PowerPoint presentations. The software installation is straightforward, and the user-interface is friendly (i.e., drag-anddrop of images). This program also provides an opportunity for academic radiologists to evaluate this new presentation technology without incurring the expense of purchasing the Flash application. W70 AJR:190, January 2008

4 Converting Image Sequences to Flash Movie Loops A C Fig. 2 Creating Adobe Shockwave Flash Movie Loop with Flash Movie Loop Creator. A C, Screen captures of freeware program Flash Movie Loop Creator show process steps for creating Flash movie loop from image sequence (50 JPEG images). These images are in supplemental data files (Fig. S1B). (Flash screen shots reprinted with permission from Adobe Systems Incorporated) D, Screen capture of Internet Explorer (Microsoft) shows sample Flash movie loop with playback controls. (Internet Explorer screen shot reprinted with permission from Microsoft) TABLE 2: Instructions for Using the Microsoft PowerPoint Macro Step Description 1 Launch (double-click) the PowerPoint file SWF_into_PPT.ppt (Fig. S1C in supplemental files). 2 Select Enable Macros from the macro dialog (If this dialog does not appear, change the macro security level a ). 3 Press the Alt and F8 keys. 4 Select Insert_Flash and click the Run button (If the Run button is grayed out or inactive, change the macro security level a ). 5 Select the Adobe Flash movie and click the OK button to finish. a To change the macro security level in PowerPoint, select Tools Macro Security from the top menu. In the Security window, select Medium at the Security Level tab, and click the OK button. Restart PowerPoint and run the template again. B D AJR:190, January 2008 W71

5 Although this freeware is capable of creating simple Flash movie loops for PowerPoint presentations, it does not provide the imagescrolling function, which is desirable for Web-based digital teaching file applications. In the next article, the final installment of this series, a robust solution using Flash to provide image scrolling for digital teaching files will be discussed. References 1. Yam CS. A solution for using dynamic data sets in electronic presentations. AJR 2006; 187:584; [web]w218 W Yam CS. Simple method for inserting Flash movies into PowerPoint presentations. AJR 2007; 188:1151; [web]w374 W Yam CS. An alternative for presenting interactive dynamic data sets in electronic presentations: a scrollable Flash movie loop. AJR 2007; 189; 1252; [web]w295 W Adobe Website: Flash File Format. com/licensing/developer/fileformat/faq. Accessed September 28, FreeImage Website: Open Source Project. freeimage.sourceforge.net/index.html. Accessed September 28, Stern E, Richardson M. Preparation of digital images for presentation and publication. AJR 2003; APPENDIX 1: Components and Utilities Used in Visual Basic (Microsoft) Programming Visual Studio 6.0 (Microsoft) msdn2.microsoft.com/en-us/vstudio/default.aspx This is the main programming language used to develop the FML Creator. 180: Yam CS. Using Macromedia Flash for electronic presentations: a new alternative. AJR 2006; 187: 584; [web]w209 W Yam CS, Kruskal J, Larson M. Using movie clips in PowerPoint presentations. Part 2. Movie editing. AJR 2005; 185: Yam CS, Sitek A, Raptopoulos V, Larson M. A simple method for extracting DICOM images from a magnetooptic disk. AJR 2004; 183: Haider MA. Extending PowerPoint with DICOM image support. RadioGraphics 2003; 23: Free Image. A free, open source graphics library. gentoo.osuosl.org/distfiles/freeimage393.pdf. Accessed October 1, 2007 FreeImage freeimage.sourceforge.net/ This is the open-source utility used in Visual Basic to load, resize, and output JPEG frames for the Flash movie loop. This utility supports a wide range of image formats as input. The FFMPEG Scout Library This is a freeware library for converting Flash video (FLV) data to SWF. FOR YOUR INFORMATION The data supplement accompanying this Web exclusive article can be viewed from the information box in the upper right corner of the article at: W72 AJR:190, January 2008