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Bombono DVD authoring tool turns 1.0

January 12, 2011

This article was contributed by Nathan Willis

Pundits may tell you that physical media will soon be history when it comes to video distribution. Maybe — but for the foreseeable future, burning video onto an optical disc is an important part of the process, particularly when you're sending content to the 90% of the public that doesn't know what a "codec" is. For that task, dropping a .MKV file onto a blank disc won't do; you need a real, honest-to-goodness DVD. Bombono is a GTK+-based DVD authoring tool that we first examined in May of 2010. Back then, Bombono had some format and authoring limitations that made it not-quite-ready for regular usage. When the author alerted us that the application had recently made its 1.0 release, I decided to take another look.

Bombono is not a video editor — rather, it is a utility for creating the linked menu structure and supporting features of the disc format. The 0.6 release reviewed in May offered a functional but no-frills subset of DVD functionality, primarily centered on building nested menus and basic navigation. But it left out several other features, and more importantly, it required that all of your disc's video content already be in DVD-compliant MPEG-2 format. The 1.0 release corrects this format support weakness, and it does add several DVD menu features — although it is still a far cry from full-featured support.

Action!

The project provides source code bundles of the new release as well as packages for Ubuntu and Fedora. In addition, openSUSE, Debian, Mandriva, Gentoo, Slackware, Arch Linux, Alt Linux, Zenwalk, and FreeBSD all have builds available, the progress of which are tracked on the site's Download page. The Ubuntu build is provided through a personal package archive (PPA), but if you already have 0.6 installed, the new release can be installed alongside it as the bombono-dvd-testing package, which installs itself in /opt/bombono-dvd-testing/ rather than in /usr/.

The 0.6 release was lightweight in terms of dependencies, requiring only mjpegtools, TwoLAME, and the dvdauthor command-line tool. 1.0 adds two new package dependencies: FFmpeg (from which Bombono inherits its new video transcoding feature) and ENCA, a text analyzer that is used for converting between video subtitle formats.

[Bitrate calculator]

Bombono's DVD authoring workflow has not changed. You start your project in the Source tab, in which you add video, audio, and still image files to the project's Media List. In addition to adding files through the built-in file browser or system drag-and-drop, Bombono can extract video from DVD discs, which is accessible through the Project menu. As mentioned above, the FFmpeg support means that you can add almost any video or audio file to the Media List; if it is not in DVD-compatible MPEG-2 (including MPEGs without the proper resolution and frame rate), a "T" icon will be superimposed on the file's thumbnail. The FFmpeg support also allows you to "mux" (i.e. multiplex) an audio and a video file together for use in the Media List; like DVD extraction this option is available in the Project menu.

The Source tab also allows you to mark chapter points in any video on the Media List. To do so, you must click on the "check" button in the list, then right-click in the video timeline at the time code you desire. Last but not least, you can use the timeline to save individual video frames as still images. This is important because Bombono does not let you directly choose a frame to use as each video's thumbnail in the menus. Saving the frame and then adding the still image to the Media List is the only alternative.

Designing a project's menus is done in the Menu tab. As in 0.6, you must create your menus in the Menu List, then edit them one at a time. You can add "frame" buttons and basic text labels in the canvas area, rearranging them as desired. The all-important linking of buttons to actions and videos is performed by right-clicking on the button and choosing the action desired — jumping to a new menu, playing a video title, sending the "play all" command, etc.

[Output tab]

The Output tab allows you to build the DVD contents (converting formats where necessary) and author the DVD image. It uses the external dvdauthor tool for this step, the progress of which can be monitored in an output panel. You have the choice of creating an ISO image, burning the image directly to an optical disc, just creating the properly-formatted DVD content folder, or running the rendering step only. This last option converts the video and audio files and creates the dvdauthor XML command file in your output folder; if you have complex changes to make beyond Bombono's feature set, you can then edit the XML file separately.

The good

Apart from the ability to painlessly convert existing video content to DVD-compatible format (which is a killer feature), the 1.0 release of Bombono does add some needed functionality that was missing in 0.6.

[Subtitle menu]

The first is subtitle support. Currently Bombono can import any subtitle file supported by FFmpeg, which includes SubRip/SRT, SSA/ASS, DVB, PGS, and XSUB. I tested Bombono with some subtitled sample files hosted by Multimedia.cx, and it does not appear that Bombono can extract subtitles from existing video files, but there are utilities (such as Gnome Subtitles) than can assist with preparing the subtitle files. Bombono 1.0 is also limited to one subtitle file per video file.

There are three new menu-editing features: motion menus, "play all" links, and customizable selection and highlight colors. Motion menus are animated menu screens. To enable animation on a particular menu, you right-click on it in the Menu tab's Menu List and open "Menu Settings." Marking a menu as animated animates all of the video elements on the menu screen; the easiest application is to generate moving thumbnails of the video links on a menu, but it could also be used to animate the background image. You can control the animation duration and looping behavior, use an external audio file, and trigger an "end action" to be executed at the end of the animation.

The customizable selection and highlight colors close a major gap in earlier versions of Bombono. For every menu, you can select an alpha-transparent color that will be overlaid on top of the selected menu item when the remote control cursor selects the item. Without it, you ran the risk of the default highlighting color being invisible against your background. "Play all" links are exactly what they sound like: you can trigger the playback of the entire menu's contents with a single button press.

A nice technical addition in 1.0 are the bitrate control features, also from FFmpeg. If you right-click each video in the Media List, you can open up a "bitrate calculator" dialog box, which allows you to manually set the video bitrate, scale the entire video up or down, or restore any changes to the file's original settings. If you come close to filling up a disc, this is a valuable feature. The menu bar at the top of the main window provides a running tab of the space used by the disc contents, but in previous releases you had no way to adjust the disc space usage. Another option in the right-click menu allows you to max-out the disc entirely, providing maximum video quality with one click.

The bad & the ugly

Even considering the functional improvements over the initial Bombono release, there are still some noticeable gaps in the application's feature set.

Minor changes were made to the menu-editing canvas, such as the addition of horizontal and vertical alignment tools, but it still lacks support for basic tasks like re-arranging the z-order of onscreen elements, cropping images, aspect-ratio preservation when scaling, and many basic drawing tools, like lines and gradients. I understand that one can create more complex images in other tools, which might excuse the missing line or gradient tools, but the missing z-ordering genuinely impairs one's ability to create a menu. The newest-created item is always on top. That means that you have to create every object to be used in the menu in the order it will be visible on-screen.

Even if that were possible to do without making mistakes, it means the designer has no freedom to change his or her mind without starting over. Similarly, although you can scale images on canvas, it is impossible to do so while preserving their shape, so users will just get frustrated and quit. Last but not least, there is no on-screen ruler to precisely lay out items on the canvas, and there is no zoom function — the canvas is always scaled to fit the window, and not even the current zoom factor is displayed.

More serious, however, is that Bombono still breaks GNOME's human interface guidelines (HIG) in rather serious ways. I gave the application a pass on this point for 0.6, chalking it up to early-in-development quirks, but some of the problems are inexcusable in a stable, 1.0 release. For starters, the menu bar mixes tabs, a text label, and a drop-down selection widget in with the actual menus (one of which, "Go," happens to be redundant because it only offers access to the always-visible tabs). The two most-used content lists (the Media List and Menu List) both use a "check" icon to represent the "edit" action, which is non-standard. The text labels used in the tabs, window panes, and content lists are inconsistent in their font style, font size, and alignment. Button and selection widgets vary considerably in size, spacing, and background color.

In addition to the obvious UI issues, there is too much reliance on right-click context menus to bring up critical functionality. Menu settings, bitrate calculations, subtitle support, button linking and alignment, inserting and deleting chapter markers, and saving still frames are all accessible only through right-clicks. That makes them difficult to discover and not keyboard-accessible.

Finally, although I applaud the addition of subtitle support in this release, the feature set still leaves off several other important DVD mastering functions, including multiple audio tracks, multiple subtitle tracks, and extra camera angles. I am sure there are video wizards who would bemoan the lack of advanced scripting and interactive features, or THX sound options, but to me those are of limited appeal to the home video author. Ultimately, Bombono markets itself as simple DVD authoring, which puts some of those features out-of-scope.

On the other hand, these issues do not prevent Bombono from writing good discs. With 0.6, I experienced corrupted dvdauthor XML files and some other problems that prevented me from actually building valid DVD ISOs. That was not the case in 1.0; I found no show-stoppers or crashes in the DVD mastering process. I was alarmed when selected an existing folder as my ISO output location and an error box told me "Folder /home/nate/bombono is not empty. We need to remove all files in it before authoring. Continue?" — I would have expected dvdauthor to use a temporary directory when building the disc image.

In the final tally, though, although Bombono 1.0 is definitely a marked improvement over 0.6 (particularly with the addition of automatic media transcoding), there are enough holes that it just doesn't feel like a 1.0 release to me. I expect 1.0 software to meet HIG guidelines, to have well-designed menus, to just not "get in my way" when doing major tasks like laying out elements on a canvas. Bombono has technical chops — I just hope its developers will try to bring the front end up to the same level.


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