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Troubleshooting

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Troubleshooting resources

Visit the Sony Media Software Web site to access product updates, look for answers in the knowledge base, contact customer support, or participate in an online forum: http://www.sonymediasoftware.com

Common questions

Why are some of my DirectX plug-ins not working correctly?

Vegas® software is a nondestructive time-based editor. As a result, there are certain types of DirectX® plugins that perform poorly in Vegas software. These types of plug-ins are roughly classified as any plug-ins that output a different amount of time than what goes in. This includes all plug-ins such as time compress/ expand, gapper/snipper and pitch shift without preserving duration. However, these types of effects plug-ins may perform suitably as bus effects, but only if just one bus is used in the project. Plug-ins that require a lot of pre-buffering (such as Sony Media Software Acoustic Mirror™ when using long impulse files) may also perform poorly.

Also, make certain that the plug-ins you use in Vegas software are DirectX plug-ins and not DXi plug-ins.

DXi plug-ins are not supported in the application and do not perform properly.

Why do I hear gaps in my audio playback?

Check to see if any Vegas software updates have been posted on the Sony Media Software and Services Web site: http://www.sonymediasoftware.com/download

Click

Updates

to access the Updates page. Any updates to the application are posted at this location.

If software updates do not address the playback problem, check these other reasons that your audio playback can gap:

• Playing back too many tracks simultaneously can overload your hard drives.

• Not enough physical RAM can cause the Windows® operating system to use virtual memory, which is slower.

• Your CPU may not be able to process a complex mix of plug-ins.

• Problematic video card settings. For more information, see Trouble-free video: hardware solutions on page 369 .

The following are some things you can check and do to make sure your system is optimized to prevent gapping.

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RAM usage

You could be gapping because virtual memory is being used. Virtual memory is a method used by Microsoft

Windows to write information to your hard drive to make room in physical RAM. This process uses a lot of your computer’s resources. Try the following to optimize RAM usage:

• Exit all background applications not in use.

• Adjust the playback buffering slider on the Audio tab in the Preferences dialog. Adjust this slider as low as

possible. However, be aware that setting it too low may cause gaps as well. For more information, see

Adjusting the playback buffering slider on page 344 .

• Mute/solo some of the events or tracks in the mix.

• Add more RAM to your computer.

Disk usage

You may experience gapping when data is not being read off the hard drive fast enough. Try the following to optimize disk usage:

• Fully defragment your audio hard drives regularly.

• Split audio usage between different physical hard drives, not just different partitions of the same drive.

• Run fewer events simultaneously. It is not how many tracks you have in the project, but how many different events are playing simultaneously that matters.

• Make sure that you trim out any silent sections of events to minimize the wasted disk access.

• Use hard drives with fast seek times and spindle speeds of 7200 RPM or greater. SCSI drives usually have better prolonged data transfer performance than IDE drives. Under Microsoft Windows XP and Windows

2000 operating systems, Vegas software can take advantage of SCSI asynchronous reads, which can be a big performance advantage.

CPU usage

If you have checked your RAM usage and disk usage and you are still experiencing gapping, you can try to adjust how Vegas software utilizes the central processing unit (CPU). Try the following to optimize CPU usage:

• Zoom out (

Ctrl +

) fully on the track view while playing so that the screen does not have to scroll to keep the cursor on it.

• Run fewer DirectX or VST plug-ins.

• Make sure that the peak files are built for all of the audio data in the project before playing. Peaks are only built for those files on screen. If all peak files are not build, you can encounter gapping when the screen scrolls as it plays and the application must build peaks on the fly. Press

F5

before playback to rebuild peaks for all of the events, on or off of the screen.

Why do mono events increase 6 dB when panning a track hard?

In Vegas software, all audio events are treated as stereo. A mono audio event is interpreted as a stereo event with the same data in both channels. If you’re using the add channels panning mode, this duplication doubles the amplitude and results in a 6 dB increase in volume when you pan a track hard left or right. Try using the constant power panning mode instead. Right-click the multipurpose slider and choose Constant

Power

from the shortcut menu. For more information, see Adjusting stereo panning on page 145 .

Why do buffer underruns occur during a test or real write to a CD?

Buffer underruns occur when data transferred to the CD-R is too slow. This may be caused by a variety of factors relating to optimizing your system. Try writing the CD at a slower speed or prerendering the audio.

For more information, see Burning a disc (disc-at-once) on page 358 .

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Why can’t I work with footage captured using an MJPEG card?

Vegas software requires that you have the MJPEG codec (for the MJPEG card used to capture the video) installed locally on your workstation. Check to make sure that the appropriate MJPEG codec is installed on your PC.

Trouble-free video: software solutions

There are literally dozens of possible configurations of hardware for editing video on a PC. While it is impossible to go into detail for each and every system, the following explains some of the concepts behind the various settings in Vegas software. Editing and playing back full-frame, 30 fps video is one of the most demanding activities for any computer. The hardware you use is an important part of the equation, but there are a number of things you can do to optimize your PC for video. The following list is arranged from the most to the least important.

• Close all other applications. When capturing video or playing it back, it is critical that no other applications interrupt this process. Close any applications that are not vital. This includes screen savers, task schedulers, and even virus-detection software. You can ensure that you have closed all unnecessary applications by pressing

Ctrl + Alt + Delete

, selecting the individual applications, and clicking the

End Task button to close them. Certain processes are required and should not (cannot) be terminated (for example,

Explorer).

• Check your virtual memory. Windows operating system uses virtual memory when RAM is low. This is a method for Windows to use the hard disk to create more memory and is sometimes called a paging file. If

Windows tries to write to the paging file during playback or capture, this can interrupt the video software and cause problems. Make sure that a different disk drive is being used for virtual memory other than the one from which you are capturing or playing your video. If you have enough space, use C:\ for virtual memory and use a physically distinct drive for capturing and playing back video.

• Make sure you have the latest drivers for your video card and capture card and the latest updates and patches to all relevant software. One caveat to this is that you shouldn’t try to fix a program that is working correctly. Many times patches and updates fix relatively minor bugs that only affect a small number of users. If you are not experiencing any problems, it is probably best not to upgrade unless the manufacturer recommends it.

• Uncompressed video may be high quality, but it results in very large files with very high data rates.

Selecting a more appropriate compression scheme (codec) will definitely improve the situation. If you are creating movies that need maximum quality, however, this may not be an option.

Trouble-free video: hardware solutions

Even with a fast computer, video is still a hardware challenge. On the other hand, it is definitely possible to properly configure a 400 MHz Pentium to work with large video files. There are three parts of your PC that are important and the speed of your CPU is not necessarily the most critical. The following list is arranged from the most to the least important.

Video subsystem

Many graphics cards (video boards, primary display cards) on a PC cannot handle full-screen, full-frame rate video. While this leads to jerky, hesitating playback, it may not actually be a serious problem. A common video configuration is to have a separate video capture card and a primary display card. In this case, the playback using the primary display on the computer may be jerky, but when you finally output the video to tape and view it on your television monitor there may not be any problems. If you are not creating movies to go back to the television or VCR and you are experiencing stuttering playback, you should consider using a smaller frame size (320X240) and frame rate (15 fps).

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Hard disk

The second most common problem is slow hard disks. Until recently, fast, expensive SCSI AV hard disks were required to properly capture and play back video on a PC. Slow hard disk problems also manifest themselves with jerky video playback, although the stutters are less frequent and of longer duration than if the video subsystem is the problem. Slower hard disks (e.g., 5400 RPM IDE) can cause an occasional dropped frame. DV enthusiasts have fewer problems due to the low data rate (~3.6 MB/sec.) of that format.

The following section outlines some recommendations arranged in order of importance.

• Buy a dedicated video drive. This is easily the most important piece of hardware advice. A dedicated, physically distinct hard drive is almost a requirement for any type of serious video work. This means that you have one primary C:\ drive (or wherever your operating system is installed) and a separate drive for video. You can use your dedicated drive for other purposes, especially storage, but it is a good idea not to run any applications from it and to keep Windows virtual memory off of it. It is very important that the drive only be used for video when playing and capturing, and that other programs (including Windows) are not trying to access it. Since video files are so large, a dedicated drive is not an unreasonable item even if digital video is just a hobby. You can never have too much hard disk space.

• Buy a faster hard drive. Older 5400 RPM hard drives may not be fast enough for capturing and playing back video for any length of time, while newer 7200 RPM drives are almost always adequate. Be careful: manufacturers are usually talking about burst transfer rates when they talk about the speed of a drive. A drive that can transfer data at 80MB/sec is worthless for video if it cannot sustain a much slower rate of

8MB/sec for thirty minutes (or more) without dropping a frame. Look to other computer video enthusiasts for additional advice. Again, the RPMs are a very good indicator, because 7200 RPM IDE drives are usually newer (c.1998) and older 7200 RPM drives are usually SCSI, which are already higher quality drives to begin with.

• IDE vs. SCSI. While this was a big issue just a few years ago, it has fortunately faded in importance. Hard drives can be hooked up to your computer in a number of ways, with the two largest divisions being IDE and SCSI. This interface simply determines how much data can be transferred to and from the drive in a second. The interface almost always far outstrips the performance of even the best hard disks and even the slower interfaces exceed the transfer requirements of video data. SCSI hard disks are usually more expensive and require a special controller, and while SCSI-2 promises 80MB/sec transfer rates, this is overkill for most people. Newer IDE hard disks with designations of EIDE, DMA, Ultra-DMA, ATA-33, and ATA-66 (and newer drives that came out after this writing) can all handle most sustained video requirements.

CPU and RAM (memory)

While the CPU and the RAM are probably the most important overall aspects of a PC’s speed and performance, these factors are only third on the list for video. For the most part, these critical components do not affect the capture or playback of video. This does not mean that a faster CPU or more RAM will not help, because bigger and faster is always better: CPU and RAM definitely impact rendering speeds. Creating a final AVI file, especially in a movie project that uses a lot of effects and transitions, can take a long time. A thirty-minute movie could easily take six or more hours to render, depending on the format and effects used.

CPU speed is also important for more advanced compression codecs, such as MPEG and newer streaming formats.

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Audio proxy files (.sfap0)

Working with certain types of media files with particular audio compression schemes can be inefficient and slow. To compensate for this, Vegas software creates audio proxy files for formats that are known to dramatically impact performance. There are two cases where this occurs.

Multimedia video files often contain both video and audio information. In certain formats, these two streams can be packed together in such a way as to make editing slow and inefficient. Vegas software therefore takes the audio stream from these files (e.g., type-1 DV, QuickTime™) and saves it to a separate and more manageable audio proxy file.

QuickTime audio-only files can also be compressed in a way that makes editing slower. Vegas software also uses audio proxy files in this situation as well. While audio proxy files may be large (because they are uncompressed), the performance increase is significant.

The file is saved as a proprietary .sfap0 file, with the same name as the original media file and has the same characteristics as the original audio stream. So movie.avi yields a movie.avi.sfap0 audio proxy. Additional audio streams in the same file are saved as movie.avi.sfap1, movie.avi.sfap2, etc. This is a one-time process that greatly speeds up editing. The conversion happens automatically and does not result in a loss of quality or synchronization. The original source file remains unchanged (the entire process is nondestructive). Audio proxy files can be safely deleted at any time since the application recreates these files as needed.

Note: Vegas software saves audio proxy files to the same folder as the source media. If the source media folder is readonly (e.g., CD-ROM), the files are saved to a temporary directory.

Interlacing and field order

Field order in interlaced video is an important parameter that can severely impact the quality of video on a television monitor. While the concept is easy enough to understand, the lack of standards in both technology and terminology clouds the issue.

The path of the electron gun across the screen is fundamentally different between television monitors and computer monitors. Computer monitors scan every line in order, from left to right and top to bottom. This is known as progressive scanning. On a standard television monitor, the electron gun scans every other line from top to bottom, twice for every picture or frame. For example, the first scan from top to bottom might scan all of the odd numbered lines first, then jump back to the top of the screen and, in the second scan, draw all of the remaining even numbered lines, completing the frame. The two fields are said to be interlaced together to form a single frame.

The illustration that follows shows how two frames in a video are actually composed of two fields each, for a total of four fields. These fields can be referred to as field one (F1) and field two (F2). Obviously, it is critical that these two fields are paired together to create a whole frame. What may not be so obvious is that the actual order of these two fields is not particularly important. In other words, F1 could be scanned first and then F2, or F2 could be scanned first and then F1. Both situations would create a perfectly valid, error-free frame of video. While that may sound like good news, in reality this is the source of all of the problems associated with field order. Since both methods are technically correct, both methods have been used. It is important to use the correct order when rendering video files for your particular hardware (capture card).

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The next illustration shows the effects of incorrectly interlacing a frame of video. In this case, F2 from frame one is combined with F1 from frame two. Remember that there is nothing inherently right or wrong with a field order of F2/F1; it just happens to be wrong in this case. At a minimum, this can create slightly blurry or hazy video. In most situations, the video is jumpy or jittery and is unwatchable. Interlacing problems can be especially noticeable when two adjacent frames are significantly different; for example, at a cut or in video with fast moving action. It can also manifest itself in certain computer-generated special effects; for example, in slow-motion sequences.

F2 F1 frame 1 frame 2 frame on television

The basic problem is that there is no standard correct field order. Some capture cards use F1/F2 and some use

F2/F1. If this were the extent of our troubles, we could check out our hardware manual, look up the correct field order and that would be that. Unfortunately (if this information is even available) the terminology used can be equally baffling. F1 may be called the odd, upper, or A field, or (more rarely) it may be called the even, lower, or B field. Add into the mix the fact that the first scan line might be numbered 0 or 1 (which changes whether the field is considered odd or even), and that cropping may change which line is ultimately scanned first, and you can see that this is not a very clear-cut problem. The remainder of this section deals with how to sort this out in Vegas software. Fortunately, you only have to determine the correct settings once for any particular hardware setup.

Identifying problems

Vegas software refers to the two fields as upper field first and lower field first. These are probably the most common terms used to distinguish the two fields, and you may find a page in your hardware's manual that says something like “Use a field order of lower first.” In many cases (but not all or even most),

Upper=Odd=A and Lower=Even=B.

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In the application, you can select the field order of a project by choosing Properties from the File menu and clicking the Video tab. The pre-configured templates should work for almost everyone (e.g., if you are editing and outputting DV video in the US, select the NTSC DV template). If you have problems, you can manually select a different field order on the Video tab. You can also override the project settings and set the field order when you render a video file. From the File menu, choose Render As . Then, click the Custom button and choose an option from the Field order drop-down list on the Video tab. You can also set field order at the level of the media file or event. Right-click a media file in the Project Media window or an event on the timeline and choose Properties . The Field order drop-down list appears on the Media tab.

Interlacing problems only manifest themselves on television monitors. Video that is going to be played back on a computer does not need to be interlaced, and you can select None (progressive scan) for the field order.

Rendered video must be displayed on a television monitor to identify any problems. The only way to see interlacing problems is to record (print) a rendered video file out to tape and play back the tape on a television. Problems are most apparent in video that has a lot of motion or that has been modified in some way; for example, a slow-motion effect. (Some codecs force the correct field order during a render, making it difficult or impossible to create video with the wrong field order.)

Solving interlacing problems in Vegas software

If your hardware’s documentation does not contain any information about the proper field order, you must determine this information for yourself. It is not a difficult process, and involves rendering one video file with an upper first field order and another with a lower first field order. Source material that dramatically and clearly demonstrates the improperly interlaced video is important: use a media file with a lot of motion in it and then slow the event down with a velocity envelope or by time-stretching the event.

Timecode

Timecode is a method of labelling frames with a unique and searchable identifier. It is primarily important for synchronizing video (in frames per second) with time in the real world and, in the case of Vegas software, with other media in a project.

Changing the timecode used to measure a video file does not alter the contents of the file. For example, no frames are ever dropped or removed when using SMPTE 29.97 drop frame timecode. Instead, specific frame numbers are periodically dropped to compensate for differences between timecode and time in the real world. Confusion between using drop versus non-drop timecode can cause synchronization problems between video and audio. For very short periods of time, the error would be unnoticeable. After about a half an hour, you might notice that mouths and words do not quite match in shots of people speaking. Longer stretches of time show larger discrepancies in synchronization.

Changing the timecode displayed on an event is not equivalent to converting a video to another format. You cannot convert NTSC video at 29.97 fps to PAL video at 25 fps by simply changing the timecode. To convert NTSC video to PAL video in Vegas software, you need to re-render the video in the new format. In this situation, the conversion process necessarily results in some frames of video actually being removed from the original sequence.

SMPTE timecode types

The following are descriptions of each of the Society of Motion Picture and Television Engineers (SMPTE) timecode types.

SMPTE 25 EBU (25 fps, Video)

SMPTE 25 EBU timecode runs at 25 fps, and matches the frame rate used by European Broadcasting Union

(EBU) television systems.

Use SMPTE 25 EBU format for PAL DV/D1 projects.

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SMPTE Drop Frame (29.97 fps, Video)

SMPTE Drop Frame timecode runs at 29.97 fps, and matches the frame rate used by NTSC television systems (North America, Japan).

Use SMPTE Drop Frame format for NTSC DV/D1 projects.

Both SMPTE Drop and SMPTE Non-Drop run at 29.97 fps. In both formats, the actual frames are not discarded, but they are numbered differently. SMPTE Drop removes certain frame numbers from the counting system to keep the SMPTE clock from drifting from real time. The time is adjusted forward by two frames on every minute boundary except 0, 10, 20, 30, 40, and 50. For example, when SMPTE Drop time increments from 00:00:59.29, the next value is 00:01:00.02.

SMPTE Non-Drop Frame (29.97 fps, Video)

SMPTE Non-Drop Frame timecode runs at a rate of 29.97 fps. This leads to a discrepancy between real time and the SMPTE time, because there is no compensation in the counting system as there is in SMPTE Drop

Frame.

Use SMPTE Non-Drop format for NTSC D1 projects that are recorded on master tapes striped with Non-

Drop timecode.

SMPTE 30 (30 fps, Audio)

SMPTE 30 is an audio-only format and runs at exactly 30 fps. SMPTE 30 is commonly used when synchronizing audio applications such as multitrack recorders or MIDI sequencers. This format should not be used when working with video.

SMPTE Film Sync (24 fps)

The SMPTE Film Sync time format runs at 24 fps (frames per second). This frame rate matches the standard crystal-sync 16/33 mm film rate of 24 fps.

Timecode in Vegas software

Video timecode crops up fairly frequently in Vegas software. Being a multimedia production tool, time in the application can be measured in real-world time (hours, minutes, seconds), in video timecode (involving frames of video), or in musical time (measures and beats).

Ruler format and timecode

The ruler in Vegas software can be set to measure time in any way that is convenient. This setting does not change how the final file is rendered, but controls the grid lines and how snapping behaves. Right-click the

ruler and choose a time format from the shortcut list. For more information, see Changing the ruler format on page 329 .

Preferences dialog timecode settings

From the Options menu, choose Preferences and click the Video tab to adjust the Show source frame numbers on event thumbnails as drop-down list. These settings take precedence over those found in the source media

Properties dialog (see the next topic) and are displayed on events inserted into the timeline. None means that no numbers are displayed on events, Frame Numbers marks frames in the media file starting with 0, Time displays the time in seconds, and Timecode allows the source media’s timecode to be detected or selected.

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Source media timecode format

Right-click an event, choose Properties , and click the Media tab to view these properties. By default, Use timecode in file is selected.

Note: You can override these settings by choosing different settings on the Video tab of the Preferences dialog. Select

Timecode from the Source frame numbering list to allow event-level specification.

Render media file format

The timecode of a final rendered media file is determined by the specified format. The frame rate of the project ultimately determines the timecode and is often constrained by the type of media file being rendered or the codec being used for compression. For example, NTSC DV is typically limited to a frame rate of

29.97 fps and uses SMPTE drop frame timecode.

Time formats in Vegas software

A variety of time formats are provided in the application. For more information, see Changing the ruler format on page 329 .

Troubleshooting DV hardware issues

Vegas software is designed to integrate seamlessly with OHCI compliant IEEE-1394 DV video capture hardware and DV camcorders. While most people never have any problems, the vast number of hardware configuration possibilities makes this a potentially complex issue. There are a number of resources at the

Sony Media Software Web site that may be able to assist you.

More detailed information is available at: http://www.sonymediasoftware.com/Support/Productinfo/OHCI.asp

You can also visit the Vegas Updates Web page to access a troubleshooting document for OHCI-compliant devices. From the Sony Media Software home page, go to the Download page and click Updates . Click the

Vegas Update link to access the update page.

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TROUBLESHOOTING APPENDIX A