Audio / Video synchronization issues

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Audio / Video synchronization issues

Post by Administrator » Fri Nov 03, 2006 5:43 pm

Because this topic is spread out over several others, I have created this thread to keep them all in one place on the 'Back up Forum' in case the original threads get destroyed either by a hacker or due to an upgrade of the PHPBB software to a later version.
The original links have been retained in this post but further down you will find the relevant topics.


Audio / Video synchronization issues
I do not want this thread to bloat and lose the useful purpose for which it is intended and so this thread will be locked. In the topics below I shall include a heading followed by various links addressing the issue. Should you wish to debate any issues please do so in the original threads. Should you wish to have a FAQ added to this thread please send me a PM - sjj1805. Thank you. Steve Jones - Tutorials Moderator

Topic: Avoid Problems: Use Recommended Procedure For Video Studio
http://phpbb.ulead.com.tw/EN/viewtopic.php?t=27
This is THE most important thread that should be read by all new users.
You are strongly advised to follow the Recommended Procedure (below) because it details steps that YOU should take to avoid several serious bugs in Video Studio. If you ignore this procedure, thinking that you can operate Video Studio intuitively, you will be disappointed and frustrated by the problems you encounter on the path to a high quality DVD. Be sure you can burn DVDs before you invest a lot of time perfecting a long video project.
Topic: VideoStudio 9 Audio Sync Problems
http://phpbb.ulead.com.tw/EN/viewtopic.php?t=12118
This thread includes an explanation of the difference between AVI files and MPEG files. It includes a description of Codec and Program Time Stamps.

Topic: AV Asynchrony, Smart Render And The Frame Redundancy Bug
http://phpbb.ulead.com.tw/EN/viewtopic.php?t=3525
Here is a very interesting and informative article written by forum member alosada
For the past several years, audioideo asynchrony in VideoStudio and other Ulead programs has been blamed on a number of factors relating to the hardware and software we use or the way we use them. However, many people have rightly complained that they follow the good practices recommended in this forum and yet continue to have AV asynchrony problems. What follows is a compilation of the results I have obtained after a fair amount of testing following my recently bumping into what might be the origin of some: the frame redundancy bug.
Topic: Audio Sync Issue...
http://phpbb.ulead.com.tw/EN/viewtopic.php?t=1467
Currently this thread is 5 pages long and so includes plenty of debate concerning out of synchronization issues.

When everything else fails view this
http://phpbb.ulead.com.tw/EN/viewtopic.php?t=11524

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Post by Administrator » Fri Nov 03, 2006 5:53 pm

The Recommended Procedure
jchunter_2 wrote:Warning: NEW USERS are strongly advised to follow the Recommended Procedure (below) because it details steps that YOU should take to avoid several serious bugs in Video Studio. If you ignore this procedure, thinking that you can operate Video Studio intuitively, you will be disappointed and frustrated by the problems you encounter on the path to a high quality DVD. Be sure you can burn DVDs before you invest a lot of time perfecting a long video project.

Tutorial Directory For detailed workflow and "how-to" guidance, see the following Tutorials.

Video Studio Version 10+ High Definition Tutorials:
Video Studio 10+ High Definition Tutorial Edit1 5/17/06

Classic Video Studio TUTORIALS (all versions):
Brian's Ramblings
DownUnder perspective
Trevor's Tutorials (edited)
Deutsche helfe.

Ulead Product Tutorials (All Ulead Products):
Ulead Product Tutorials


Use the SEARCH button. Lots of information is available in this forum on numerous problems. It is quite likely that a solution to your problem is already in the forum database. The Ulead Knowledge Base is also available.

Video Studio Updates

Updates and Bug Fixes are available for Video Studio versions 7, 8, 9, and 10 Here
Users experiencing audio/video synch problems with version 8.0 may find relief by upgrading to Video Studio 10+.

Getting Help from Video Studio Forum Members:
New Users: Please enter your operating system, computer speed, Memory capacity, available disk space, etc. in your forum profile because this will assist those users in diagnosing your problem(s).

If you want help, please provide ALL the details that you can: Video Studio Version, Captured Video Properties, Project Properties, Burn Properties, error message, etc. These video properties contain essential diagnostic information. If you don't provide them you may not get much help. To find your Properties, right Mouse on any video clip and select Properties. See Recommended Procedure for examples of video properties.

Newbies take note: The most common mistakes are
(1) Setting the wrong video PROPERTIES.
(2) Following the wrong procedure.
Either one can ruin your cherished video and waste a lot time doing it.


Recommended Procedure for Success with Video Studio
The following is all about problem avoidance - see the Tutorial Directory (above) for detailed "how-to" information.

NEW USERS: The following procedure/work flow is recommended when using VIDEO STUDIO because it has had the most success at producing good quality DVDs. In particular, it avoids triggering serious bugs, so please follow the process carefully.

The most important messages in this procedure are:
(1) Always Create a Video File of your entire project before attempting to burn a DVD,
(2) Never try to burn a DVD with anything in the EDIT Timeline display,
(3) Never try to burn a DVD using SHARE/Add Project button.
(4) Make certain that your BURN properties exactly match your DVD-Compliant VIDEO FILE properties.



Capture Phase

Your first challenge is to get the video from the camcorder into the computer. As a vastly oversimplified introduction, there are basically two types of video sources: Analog (older camcorders and VCRs) and Digital (newer camcorders). There are also two possible target video file formats in the computer: Mpeg2 and AVI(DV). Mpeg2 is the file format required for burning DVDs and DV (Digital Video) is the native file format of most digital camcorders. High definition editing is covered in a separate HD Tutorial


Analog Video
Most computers require an external capture box to which one can connect an analog signal source (S-Video or composite). These often contain a fast, dedicated processor that converts the video to Mpeg2 format and stores it directly in the computer hard disk, using either a Firewire (IEEE 1394) port or a USB2 port.

Many analog capture products are not supported by Video Studio. If you have difficulty, use the capture software (e.g., CapWiz) that came with the box to capture the video files - then edit with Video Studio.

Digital Video (mini-DV)
Most digital camcorders have a Firewire connector and so can attach directly to a firewire port on the computer. Don't try to capture video with the USB cable that came with the camcorder - it is usually for transferring still images to the computer.

Capture Guidelines Standard Definition: (For high definition capture, see HD Tutorial link above.)
Capture Mpeg2 format ONLY if you have a fast computer (>2.5 GHz, 1GB RAM, disk with > 20 GB of available unfragmented space). If you capture in DVD-Compliant Mpeg2 format, the whole video editing process to DVD burn will be faster and simpler.

If your computer CPU is slower than 2 GHZ, capture to AVI (DV) Type 1 because capturing in Mpeg 2 format puts too great a load on the CPU. DV Type 1 is recommended because users have experienced problems with AVI Type 2. DV files are about three times larger than Mpeg2 files (~13 GB/hr), so be sure you have enough free disk space.

You can capture directly with Video Studio by selecting the CAPTURE tab.

Set the Capture Properties
If you want the best quality and plan to burn to DVD, set high video bit rate properties (Variable, 8 Mbps) and the best frame size (720 x 480 NTSC, 720 x 576 PAL). If you have a low resolution video source such as VHS tape and want to store a lot of video on a single DVD, you can use a lower bit rate (3-4 Mbps).

Field Order property: Upper Field First for analog video, Lower Field First for digital video.

The following capture properties will yield good quality video when burned to a DVD. (In PAL country, substitute 25.00 fps for 29.97 fps and substitute 720 x 576 for 720 x 480):

Mpeg Capture Properties:
NTSC drop frame (29.97 fps)
MPEG files
24 Bits, 720 x 480, 29.97 fps
Lower Field First for digital capture {if capturing analog use "Upper Field First"}
(DVD-NTSC), 4:3 (or 16:9 for widescreen)
Video data rate: Variable (Max. 8000 kbps)
Audio data rate: 224 kbps
MPEG audio layer 2, 48 KHz, Stereo

AVI(DV) Capture Properties:
NTSC drop frame (29.97 fps)
Microsoft AVI files
24 Bits, 720 x 480, 4:3 (or 16:9 for widescreen), 29.97 fps
Lower Field First {if analog use "Upper Field First"}
DV Video Encoder -- type 1
DV Audio -- NTSC, 48.000 kHz, 16 Bit, Stereo

Tip: In VS7&8, Enable the Drop Frame Counter to monitor your capture quality as follows:
Documents & Settings\\All Users\\Application Data\\Ulead Systems\\Video Studio 8. Open UVS.INI and scroll down to Information? and change the Show Drop Frame Counter from =0 to =1 Save the changes.

In VS9 and VS10, select menu File/Preferences/Capture tab: check "Show Drop Frame Information"

If you elect to capture digital video direct to NTSC Mpeg2 using Video Studio 9.0 or 10, set the Capture properties as shown in the figure below(Dolby audio is supported in VS9). If capturing Analog video, set Output Field Order to Upper Field First:

Image


Edit Phase

Note: If you captured in DVD-Compliant Mpeg2 format and do NOT want to edit your video, you can skip this Edit phase and the next (Create Video File) and continue with "Burn DVD Phase" to immediately burn a DVD.

1. Select Menu FILE/Preferences. Place a checkmark next to "Show Message When Inserting First Clip..."
2. Drag one of your .captured video files into the empty timeline display.
3. When it asks "Do you want to Set Project Properties to Match..." press Yes.
4. Select Menu FILE/Project Properties. Click dit.?Open the Compression tab and select Media Type = TSC DVD?(or PAL DVD if you live in PAL country).
5. Move the Quality Slider to 100. Set Data Rate to ariable.?The Bit rate and Audio settings will already be set properly to match your captured video. Press OK. Check erform Non-Square Pixel Rendering.? Print the Project Properties in the lower window and stick it on your wall. Memorize it.
6. Now complete your video editing - add audio, titles, transitions, cut out shaky video sections, too-fast pans and zooms, pictures of the inside of your camera bag, :wink: etc. How to use the Edit controls is outside the scope of this brief intro.
7. You can insert digital still images (e.g., jpeg files) freely, at full resolution into the timeline. Set menu File/Preferences/Edit tab "Image Resampling Option" to "Keep Aspect Ratio" and "Resampling Quality" to "Best" before insertion. Opinion: Simple cuts are less wearing on the audience than transitions between still shots. Time the cuts to coincide with beat of your background music.
8. Save your project.

Create Video File Phase

Note: This phase is crucial because it avoids serious bugs in Video Studio. Always create a video file of your project before attempting to burn a DVD.

If you captured your video in Mpeg2 format, you will be able to "Smart Render" your video file relatively quickly:
1. Select SHARE/Create Video File
2. Select ame as Project Settings? (Only if your project properties match your captured video files exactly. Otherwise, use the AVI(DV) procedure below.)
3. Name your video file and hit the SAVE button.
4. You can review your video file using Windows Media Player (or Video Studio). Media Player Classic (MPC) is also an excellent video player (free) that also plays high definition video files.

If you captured AVI(DV) format, you will have to transcode your project to Mpeg2 before burning a DVD, which can take a LONG time:
1. Select SHARE/Create Video File
2. Select Custom then set Save as Type = "Mpeg"
3. Select Options, Select "Compression" tab. Set Media Type = NTSC DVD (or PAL DVD). Select Video Data Rate = Variable, (e.g. 8000 kbps or 3-4 Mbps for low resolution sources)
4. Now examine every setting on all three tabs to make sure every property setting matches the following pictures (Note PAL has different frame size and rate, Analog video is Upper Field First, Widescreen video should be set to 16:9).
5. Name your video file and hit the SAVE button.

Setup for Creating an NTSC DVD-Compliant Video File:

Image
Image Image


Burn DVD Phase
Caution: Never try to Create a DVD with anything in the timeline. Do not use the SHARE/Create Disk/Add Project control option.

1. Select NEW project.
2. TBD
3. Select SHARE/Create Disc
4. Press ADD VIDEO button. Navigate to select your Mpeg2 video file. It will appear in the lower display.
5. Click the little Gear-Shaped icon on the lower left, second to the right to set the properties for the DVD burn.
Burn property setup is the same as shown above for Creating Video files.
6. Press "Change Mpeg Settings", then press "Customize," then the "Compression" tab.
7. Media Type should already be selected. Push the quality slider to 100%.
8. Set all burn properties to exactly match the properties of your Project Video File.

Version 10+ note: The DVD menu set up is different from here on. Update TBD.
9. Now press Add/Edit Chapters and use the jog bar set up your DVD Menu entry points.
10. Press Next. Now edit your DVD Menu labels, choosing each one from the selector at the top.
11. Optional Step: You can save all your DVD menus by pressing "Close". Select FILE/SaveAs and name this project "BURN Project" or something like that. Then, when you open this Burn project again and press SHARE/Create Disc, everything (menus, etc.) should still be there.
12. Skip to the last screen, Check Record to Disk if you are ready to burn. If not, you can check "Create DVD Folders" and/or
create Disc Image File," instead.
13. If burning, verify the Required vs. Available disc space.
14. Hit the Output button. Burning should take about 30 minutes at 4x
15. If you see a message that says "Converting Videos, This will take a long time..." hit the Cancel button and check for the following problems (1) Burn properties do not match Video File properties, (2) Timeline display is not empty, or (3) You have used the Add Project control.........

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VideoStudio 9 Audio Sync Problems

Post by Administrator » Fri Nov 03, 2006 6:06 pm

VideoStudio 9 Audio Sync Problems
In the list of top 10 frequently asked questions this one would rank number 1.

There are several posts concerning this and a search will find plenty of information. but in a nutshell here it is again kept simple.
Video is a series of still pictures passing in front of your eyes very fast.
In the PAL system 50 pictures every second made up of 2 frames upper and lower to make 1 complete frame and so described as 25 frames per second.
The NTSC system comprises of almost 60 pictures and so you get just under 30 frames per second (29.97). Linked to these pictures are sound files. The reason for the difference between PAL and MPEG is due to the electricity supply of that particular country.

Here I will describe the problem in PAL
Now then lets just imagine 50 BMP pictures every second each measuring
768x576 pixels. Wow thats going to be huge and one hours worth of video will devour some 80 gigabytes of Hard Drive space.

So we introduce something called compression to make the file sizes smaller. We will also need something to decompress the files again later so we have COmpression and DECompression and end up with something called a CODEC.

There are many CODECs in existence some are what are known as lossy and others lossless. Those files known as lossless are grouped together into what are termed AVI files (Audio/Video Interleaved.)
Think of these compressed AVI files like you would a TIFF file in the still image world. Smaller in file size but retaining the quality of the original BMP.

The lossy files are termed MPEG. (Before anyone jumps in I am keeping this simple and easy to understand.)

Normal video editors such as the Ulead range, Adobe Premier, Pinnacle, Sony etc are designed to work with AVI files (lossless) and so editing AVI files should not produce out of synch problems. Eventually the completed AVI files will be compressed into an MPEG (Lossy) format to create the DVD VOB files.

DVD VOB files are MPEG files but also contain slightly more information than a normal MPEG file which is why simply renaming VOB to MPEG does not always work correctly.

Now back to MPEG files.
Think of an MPEG as being the motion equivalant of its still image cousin a JPG. The picture is considerably smaller than the BMP file as a lot of details has been discarded though to the eye seemingly unoticeable.
If however you edit these files they get compressed again and even more detail gets dumped and eventually those details become very noticeable.

Another point to be considered here is that part of the MPEG compression process is that these files are not all complete pictures. Instead they are made of of groups of pictures termed a GOP.

The standard GOP file is either 12 or 15 frames long dependant usually upon if you are using NTSC or PAL.
Futher explanation of GOP here:
http://en.wikipedia.org/wiki/MPEG-2
Put simply you get a complete picture on each i-frame but only information concerning changes to that picture on the b and p frames.

There is an interesting article by Terry Stetler - Moderator of the Media Studio Pro forum about changing the size of the GOP structure when dealing with fast action movies like racing cars.
http://phpbb.ulead.com.tw/EN/viewtopic.php?t=10880

Now then back to our out of synch problem.
Tied into the GOP structure are flags in the video stream and flags in the audio stream designed to keep them synchronised. These are termed Program Time Stamps otherwise termed PTS.

The Audio stream does not have a GOP structure it remains continous.
When you cut the video then mainly due to the video GOP structure you destroy the synchronisation between the two streams and end up with the sound usualy ahead of the video. I dont know for sure but I suspect that when you cut the GOP it probably goes back to the nearest preceding i-frame.

So then, whats the cure?

1. Only edit AVI files. Only convert to MPEG when you are ready to author the DVD.
2. If option 1 is unavailable - perhaps your capture software will only capture in MPEG format (example - my Hauppauge TV card.)
Then you need to use a purpose built MPEG Editor such as Womble http://www.womble.com/products.dvd/
or
VideoRedo http://www.videoredo.com/index.html
3. You may get lucky if you pass an out of synch file through one of the above two products which have modules to try and correct PTS problems.
4. When all else fails and only as a last resort you can do a quick fix that will at least make an out of synch video watchable by following my tutorial here http://phpbb.ulead.com.tw/EN/viewtopic.php?t=11524

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AV Asynchrony, Smart Render And The Frame Redundancy Bug

Post by Administrator » Fri Nov 03, 2006 6:13 pm

AV Asynchrony, Smart Render And The Frame Redundancy Bug
alosada wrote:For the past several years, audio video asynchrony in VideoStudio and other Ulead programs has been blamed on a number of factors relating to the hardware and software we use or the way we use them. However, many people have rightly complained that they follow the good practices recommended in this forum and yet continue to have AV asynchrony problems. What follows is a compilation of the results I have obtained after a fair amount of testing following my recently bumping into what might be the origin of some: the frame redundancy bug.

This topic is presented in three posts. This first post introduces the problem, which is explained in greater detail in the second (more about the FR bug?. Finally, the third post provides sort of a standard test for checking whether one's VideoStudio version produces the bug.

Although the focus is on VideoStudio, the key points also apply to Movie Factory and MediaStudio Pro. For specific information about the latter two, please read what about other Ulead programs? in post 2.

I apologize for taking up so much forum space and for any inconsistencies in the discussion. I hope it may be of help to clarify the issue anyway.

What is the frame redundancy bug?
As we know, AV asynchrony can be gradual or non-gradual depending on whether it increases uniformly throughout a clip or only, abruptly, after specific points in it.

Gradual asynchrony often arises from the video and audio in a clip being acquired separately via two devices such as a video capture board and a sound card. Any difference in sampling rate between the two can result in the lengths of the video and audio streams captured after some time not matching, the gap widening with time.

With non-gradual or abrupt asynchrony, however, the video and audio may be mismatched virtually from the beginning. The problem can grow at specific points, but usually doesn't in between unless gradual asynchrony is also present.

Non-gradual asynchrony is usually the result of a captured file containing dropped frames or acquiring them at some time during its processing. In VideoStudio, it often arises from the editing of mpeg files. So, while just removing a few portions from an mpeg clip should pose no problem, it seemingly does in some versions.

This self-caused problem is what we might call the frame redundancy bug a software glitch that artificially lengthens the video stream of an edited mpeg clip upon re-encoding and may be behind some elusive OOS issues reported in this and other Ulead forums.

What are the symptoms and how can they be detected?
The frame redundancy (FR) bug has a visual impact and also what seem to be audio-related effects but are actually the consequences of its altering the video stream. Its principal visual effect is jerky scene changes as if the action froze or the video were played backwards for a split second.

Besides, the FR bug introduces non-gradual AV asynchrony that builds up as it surfaces at each edit point in the video stream. In fact, the bug sends the video in a clip out of synchrony (OOS) with its audio by effect of its introducing spurious, redundant video frames that artificially increase the length of the video and cause it to be misaligned with the audio.

The outcome is a departure specifically, a delay of the video from the audio that grows as the number of redundant frames increases. For more details, please read the effects of the bug in post 2.

Identifying the FR bug from its symptoms is rather difficult, if not impossible, in VideoStudio because it manages to skip the spurious frames and not display them. Also, like most software capable of playing back mpeg files, VideoStudio can realign the video and audio streams in a clip approximately every 0.5 seconds, so any audio or video delay will normally go unnoticed until the buggy file is converted into VOBs for burning onto a DVD. Please read why is the AV asynchrony initially not apparent??in post 2 for more details.

Consequently, accessing and inspecting redundant frames requires using an appropriate external program as described in detecting the FR bug and identifying its effects?in post 2. While it can also be done in VideoStudio, the procedure is rather cumbersome as it involves using the buggy file to make an OOS VOB with a burning engine version unable to repair the asynchrony.

What causes the bug and what doesn't?
The FR bug arises when a previously captured or rendered field-based mpeg2 file the video stream of which has been touched in any way is smart rendered. touched here means trimmed or applied any visual effects and visual effects?include transitions, video filters, titles, overlays and even playback speed changes. Also, note that all clips obtained by using Clip > Save Trimmed Video on the VideoStudio menu are smart rendered.

AV asynchrony has sometimes been ascribed to a bug in the CD/DVD Burning Engine. Any such bug is definitely not the FR bug. In fact, while installing Ulead's succession of updates to the files in the \\Ulead Systems\\DVD shared folder may have left some systems defenseless against the effects of the bug, the burning engine is not the origin, but the solution to the OOS problem caused by VideoStudio itself.

Unfortunately, some versions of the engine fail to repair the AV asynchrony. You can check whether yours does in which burning engine versions work? in post 2.

Going to Create Disc directly to burn a project on the timeline rather than encoding its contents into a single mpeg file first has also been cited as a source of AV asynchrony. Again, this has nothing to do with the FR bug. Why? Because VideoStudio first encodes the clips on the timeline into a file named ~convert###.mpg from which it then produces the required VOB file(s). Because the conversion and multiplexing (VOB-making) operations are sequential, not simultaneous, the burning engine is given the opportunity to correct the asynchrony resulting from the redundant frames contained in ~convert###.mpg as explained in how is the AV asynchrony repaired??in post 2.

For identical reasons, using Add VideoStudio Project instead of Add Video in the Create Disc step does not trigger the FR bug either.

The bug never occurs in frame-based videos, which include all mpeg1 files, but only in field-based (Lower Field First or Upper Field First) mpeg2 files.

Although it has a deceptive impact on the audio, the bug is associated to no specific audio format (LPCM, MPEG, AC3) or sampling mode rate bitrate combination as, in fact, it doesn't alter the audio stream. Therefore, it doesn't arise from treating the audio in any way such as normalizing the volume, inserting fading-in/out effects or using an audio filter, for example.

Also, the FR bug is unrelated to whether square or non-square pixels are used, or whether the edited file is encoded using CBR or VBR, whichever the video bitrate.

Finally, simply joining two previously encoded mpeg clips doesn't trigger the bug unless a transition is inserted between the two or some visual effect is applied to either.

What is the origin?
Smart rendering involves scanning the clips that make up a project in order to detect any changes made with respect to the original mpeg file(s) and re-encoding only small portions on both sides of each edit point. edit point here means the frame immediately following the last in a portion trimmed off a clip (that is, the first frame retained after a cut) or that following the last frame affected by a visual effect be it a transition, filter, title, overlay or playback speed change.

In smart rendering the timeline contents, VideoStudio spuriously encodes a couple of frames in the vicinity of each edit point twice, thereby introducing two redundant frames into the video stream. This causes the video to depart from the audio in much the same way dropped video frames do.

For a more detailed explanation, please read how does VideoStudio produce the redundant frames??in post 2.

Is there a cure?
There is at least for the OOS problem. In fact, the appropriate versions of the burning engine manage to repair the AV asynchrony introduced by the FR bug and to produce synchronous VOBs and DVDs as long as the source mpeg file isn't subject to asynchrony of a different origin as well.

In any case, the burning engine does not remove the bad frames, so the video will still exhibit jerky scene changes at edit points when converted into VOB files and, ultimately, a DVD.

Unfortunately, once an mpeg file containing redundant video frames is rendered into one or more OOS VOB files as a result of using an ineffective burning engine version, restoring AV asynchrony is difficult and time-consuming, if not impossible. Also, a DVD made from such an mpeg file in non-Ulead authoring software will be OOS unless the file is previously repaired by using an appropriate mpeg editor.

By exception, the AV synchrony in an mpeg clip which was obtained by using Save Trimmed Video on the Clip menu can be restored albeit only at its very end by re-rendering the clip with SmartRender disabled. This can be used to assemble virtually synchronous long composite files from short clips previously rendered with the STV function.

Removing the redundant frames in order to avoid their visual impact is even more complicated. In fact, some video editing and repair programs automatically delete the two frames following each pair of redundant frames rather than the offending frames, so getting rid of the latter is an elaborate process that includes splitting the video and audio streams, trimming the bad video frames by hand and rejoining the two elementary streams into a synchronous program stream bviously, with SmartRender off this time.

Please read how is the AV asynchrony repaired? in post 2 for further details.

Can the bug be avoided?
As usual, prevention is better than cure here. So, the FR bug can always be avoided by re-encoding (that is, dumb rendering) one's projects with SmartRender disabled. It is therefore advisable to keep project (vsp) files at least until one has checked that any VOB files made from them are not subject to the FR bug since once an edited file is saved with SmartRender on, the redundant frames produced will be preserved throughout the process unless they are removed by trimming the clip portions that contain them.

With Smart Render disabled, VideoStudio does not simply rebuild small clip portions at edit points. Rather, it re-encodes the whole timeline contents frame by frame. For this reason, dumb rendering an mpeg file takes much longer than smart rendering it roughly as long as transcoding an avi file to mpeg format.

Which VideoStudio versions cause the FR bug?
In VideoStudio, the FR bug was possibly introduced by Update 6.02, dated 11/28/02. This patch revamped the Ulead MPEG.Now video encoding engine, which was made up to 46% faster possibly by reducing the length of the portions that were re-encoded on the two sides of each edit point. Although I have never used VS 6, judging by some comments posted in other, non-Ulead forums, something changed or the worse as regards smart rendering in that version.

In my experience, both VideoStudio 7 and 8 produce the bug. On the other hand, VideoStudio 9 seems to smart render properly. In fact, I have so far obtained synchronous VOBs from edited mpeg files ranging from 1 minute to 2 hours in length and containing between 1 and 60 edits including trimming, mixed transition types, titles, overlays and playback speed changes.

The only, minor glitch I have found in smart rendered VS9 files is the presence of spurious macropixels such as those seen in redundant frames when the edit point coincides with the first frame in a GOP. In any case, the frames containing the macropixels are not redundant, so they introduce no AV asynchrony.

What about other Ulead programs?
Please note that the comments which follow are based on the results obtained with trial versions, so they may or may not apply to the full programs.

Like VideoStudio, Movie Factory 4 (MF4), its predecessor (MF3), and MediaStudio Pro 7 (MSP7) are subject to the frame redundancy bug. Also, MF3 and MSP7 deliver synchronous VOBs and DVDs from files containing redundant frames, both with their native burning engines and with any other effective version. On the other hand, the burning engine in MF4 only repairs AV asynchrony in files which have acquired the FR bug in another Ulead program. Why?

Although the ~convert###.mpg files smart rendered by both MF4 and MF3 from their own projects contain redundant frames, those produced by MF3 are rogram?files (that is, files containing both audio and video), whereas those rendered by MF4 are elementary video-only files. MF4 uses its video-only ~convert###.mpg files in conjunction with their matching elementary audio-only files (whether .mpa, .wav or .ac3) to assemble VOB files with the aid of a third, .pts file which presumably contains the presentation time stamps of the video GOPs. The process, however, fails, and the result is OOS VOBs despite the fact that MF4 uses virtually the same burning engine as VideoStudio 9.

Unlike MF4, however, VideoStudio's latest version uses program (that is, self-contained) rather than elementary (video-only) ~convert###.mpg files when rendering a project directly from the timeline or adding one instead of a previously created mpeg file in the Create Disc step. In addition, the ~convert###.mpg files produced by VS9 contain no redundant frames.

Finally, DVD Workshop 2 produces synchronous DVDs from mpeg files subject to the FR bug, both with its own burning engine and with other effective versions.

The specific burning engine versions used by each program are listed in which burning engine versions work in post 2.

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Post by Administrator » Fri Nov 03, 2006 6:41 pm

MORE ABOUT THE FR BUG
alosada wrote:The effects of the bug
As noted in the first post, VideoStudio introduces a pair of redundant frames at each edit point when it smart renders a field-based mpeg2 file. As a result, the audio goes ahead of the video by two frames after the edit point. For example, if two redundant video frames (R1 and R2) are inserted at position 5 in the following stream

V1V2V3V4V5V6V7V8V9
A1A2A3A4A5A6A7A8A9

the result is

V1V2V3V4V5R1R2V6V7
A1A2A3A4A5A6A7A8A9

so the seventh video frame, which was initially matched to the seventh audio frame, is now aligned with the ninth and the audio is therefore two frames ahead of the video.

As new pairs of RFs are inserted at subsequent points, the gap between the video and audio grows, so, when playing back any VOBs made from the smart rendered file, the audio will finish before video to an extent proportional to the number of redundant video frames present in the buggy file.

An NTSC frame lasts one-29.97th of a second (that is, 33.37 milliseconds) and a PAL frame one-25th (40.00 ms). Each pair of redundant frames therefore introduces a lag of 66.74 ms in NTSC files and 80.00 ms in PAL files. As a result, the video in a spuriously smart rendered file will be delayed with respect to the audio by about 1 second (1000 ms) after 15 (1000/66.74) pairs of bad frames (that is, 15 edits) in an NTSC file or 12 (1000/80) in a PAL file.

The asynchrony, however, may start at the very beginning of the clip. So, if a captured file is trimmed to remove the commercials preceding a show, for example, the first pair of redundant frames in the smart rendered mpeg file will normally appear within the first 0.5 seconds and an audio delay of 67 ms (NTSC) or 80 ms (PAL) which is long enough for some people to notice will be present virtually right from the start even if the original clip goes through no further editing.

Why is the AV asynchrony initially not apparent?
The video and audio streams in an mpeg file that contains redundant video frames usually appear to be in perfect synchrony during playback in programs such as WMP, Ulead DVD Player or VideoStudio itself. Only after the file is burned to a DVD or converted into VOB files does the problem become apparent. Why?

During playback, the timing information contained in an mpeg file (so-called presentation time stamps) helps software players align video frames with their matching audio frames (that is, to present them simultaneously at the right time). As a result, AV asynchrony problems usually go unnoticed since most players are capable of resynchronizing the video and audio at the start of each GOP (that is, approximately every 0.5 seconds).

However, when an mpeg file is converted into VOBs for burning onto a DVD, the video and audio streams which together form a program stream?are first separated (demultiplexed) as two elementary (video and audio) streams that are then rejoined (multiplexed) to make a new program stream (one or more VOB files).

Because the separate, elementary streams contain no presentation time stamps, any redundant or missing frames in either will inevitably lead to desynchronization of the video and audio when they are recombined as their frames will have to be matched blindly in the order they appear in their respective streams with no provision for potential misalignment at any point.

Detecting the FR bug and identifying its effects
How does one know whether a file contains redundant frames?
Detecting the presence of the FR bug in an mpeg file could be as easy as comparing its length with the combined length of the bits from which it was rendered (that is, the project length). The latter is displayed as project duration in VideoStudio 9 ─and under project preview range in VideoStudio 7 and 8─ while the project containing such bits or clips is on the timeline click the Share tab and then the Edit tab if you don't see it.

However, the duration of an mpeg file containing redundant frames one sees in VideoStudio (for example, by right clicking its thumbnail and selecting Properties) is not its actual length, but rather the one it would have had if the project had been properly rendered.

An external program is therefore needed to determine the true length of files having the FR bug. One such program is VirtualDub MPEG2, which is available for free at

http://fcchandler.home.comcast.net/stab ... -MPEG2.zip

VirtualDub will tell you the exact number of video frames a file contains, which you will then be able to compare with the duration of the project used to encode it if you still have the .vsp file. If the rendered mpeg file has more video frames and is thus longer than its parent clips together, then you can suspect it contains redundant frames. The difference will normally be an even number as each instance of the bug introduces a pair of redundant frames.

What do redundant video frames look like?
In a word: scrambled. In fact, unless closed GOPs rather than open GOPs the standard in VideoStudio have been used from the beginning, the redundant frames contain a number of spurious large square blocks 16x16 pixels in size. Oddly enough, these macropixels are invisible in stills captured from the bad frames, so if you want to take a snapshot of a redundant frame you will have to use screen capture software.

Also, the frames can only be inspected in programs affording smooth frame-by-frame navigation through the video stream without skipping redundant frames. VirtualDub MPEG2 is one such program.

In any case, locating the redundant frames is easier when the project from which the suspect file was rendered is still available and the exact points in time where some edit (cut, transition, filter) was introduced can be used to determine their positions in the rendered file. Alternatively, you can use insert scenes as chapters in the Share step to help you locate the redundant frames produced by trimming or any visual effect except an overlay.

After you have recorded the positions of your edit points, open the suspect file in VirtualDub and navigate or jump to their immediate vicinity in order to inspect the individual pictures one by one in search of the tell-tale macropixels.

How can AV asynchrony be checked?
As noted previously, VideoStudio is normally useless to check mpeg files for AV asynchrony as it manages to align their video and audio as if they were in perfect synchrony and so does Ulead DVD Player, for example.

As before, you will need an appropriate program for this purpose. VirtualDub MPEG2 is fit for mpeg files, but Windows Media Player is not as it conceals AV asynchrony in them just like Ulead software does. Please note, however, that VirtualDub cannot play back Dolby audio and that WMP requires installing an AC3 codec other than the Ulead's for this purpose. You can download a free AC3 codec that works with WMP here:

http://www.free-codecs.com/AC3_Filter_download.htm

On the other hand, the best free program for checking whether DVD files (VOBs) are OOS and also for fitting overly long VOBs onto a DVD, which is its primary purpose? is probably DVD Shrink, which you can obtain here:

http://www.dvdshrink.org/where.html

WMP is also fit for detecting AV asynchrony in VOBs, an so is obviously any software-based DVD player such as Ulead's.

Which burning engine versions work?
Nearly all burning engine versions released by Ulead since VideoStudio 7 was launched allow both VS7, VS8 and VS9 to produce synchronous VOBs from mpeg files containing redundant frames. Such versions, identified by that of the file ULCDRDrv.dll in the \\Program files\\Common files\\Ulead Systems\\DVD folder, include the following:

2.9.2.98, dated 12/06/02 and released with VS7
3.4.8.162, dated 07/29/03 and released as the D/DVD Plugin Patch?
3.6.15.218, dated 03/12/04 and released with VS8
3.6.15.232, dated 04/21/04
3.6.8.260, dated 01/31/05 and released with VS9

On the other hand, the following updates to the burning engine don't repair the AV asynchrony produced by the FR bug:

3.6.15.239, which was first released as a stand-alone file package on 06/03/04 and then included in the VS 8.01 update patch (06/07/04)
3.6.17.246, dated 07/27/04
3.6.17.255, dated 10/22/04

Therefore, all versions predating the native burning engine of VS9 and following that of VS8 are ineffective to correct the AV asynchrony produced by redundant frames. If one doesn't have VS9 and has applied any of the intervening burning engine updates, then regaining the ability to repair the asynchrony requires restoring the original files in the VS7 or VS8 \\Program Files\\Common files\\Ulead Systems\\DVD folder at the expense of missing any enhancements introduced by the subsequent, ineffective versions.

The foregoing also applies to Movie Factory, MediaStudio Pro and DVD Workshop, which produce synchronous VOBs both with the previous effective burning engines and with their own native files, namely: version 3.0.2.104 (dated 12/05/02 and belonging to the bundled MF2) in MSP 7; v. 3.5.13.196 (11/26/03) in MF3; v. 3.6.14.201 (12/24/03) in DVD Workshop and v. 3.6.8.260 (01/06/05) in MF4 he last, however, fails with the ~convert###.mpg files produced from MF4 projects.

How is the AV asynchrony repaired?
In order to repair the AV asynchrony introduced by redundant frames in an mpeg file, the burning engine shortens the time each frame following them in the resulting VOB file is displayed as required for the video to catch up with the audio within a reasonable time which is usually only about half a second. In this way, it forces DVD players to display up to 32 NTSC frames or 27 PAL frames in one second that containing each pair of redundant frames.

On the other hand, those burning engine versions that fail to correct the asynchrony when multiplexing the elementary streams complete the audio stream before the video stream, so they have to add some audio actually, some silence at the end of the VOB in order to match the surplus video frames.

As noted in is there a cure? in post 1, VideoStudio can also correct the asynchrony caused by the redundant frames present in mpeg files obtained by using Save Trimmed Video on the Clip menu without the need to wait until the Create Disc step. In fact, in dumb rendering an STV clip, VideoStudio removes a couple of frames at the end, so the number of video frames matches that of audio frames and the two streams are properly aligned beyond that point. This can be used to assemble virtually synchronous long composite files from short clips previously rendered by using the STV function as the audio lag within each clip will never exceed about 67 milliseconds in NTSC files and 80 ms in PAL files which may be quite acceptable or even undetectable.

How does VideoStudio produce the redundant frames?
Trimmed clips
When a video clip is trimmed, VideoStudio splices the segments preceding and following the trimmed portion after reconstructing the tail of the former and the head of the latter. In the process, it closes the last GOP in the tail (the pre-GOP) and sets the broken link flag on the first GOP in the head (the post-GOP).

While redoing the tail of the segment preceding the trimmed portion normally poses no problem for VideoStudio, the program fails in reconstructing the head of the segment following it. So, it encodes the last two frames in the post-GOP twice and uses the two redundant frames to open a new GOP immediately after it.

In fact, once it has encoded the last frame in the post-GOP, it starts a new GOP with two B frames preceding the first I frame in it. However, instead of starting with the frame naturally following the last in the post-GOP, it rolls back two frames in the sequence and encodes the last two in the post-GOP again, using the latest P or I frame available as backward reference B frames can be encoded with respect to a previous I or P (backward reference) frame and a subsequent I or P (forward reference) frame.

If the post-GOP consists of a single, I frame, then the first redundant frame in the pair is the last frame in the trimmed portion which should obviously not be present in the rendered clip?and the second is the last and only frame in the post-GOP, which is used as the backward reference for both.

Finally, if the post-GOP contains zero frames (that is, if no GOP was broken in the head of the segment following the trimmed portion because the cut was made at an I frame), then the two redundant frames are the last two in the trimmed portion which, again, should not be there as they were supposed to have been removed?and their backward reference is the last frame in the pre-GOP which is also the latest P or I frame available.

When a whole number of GOPs is trimmed from the beginning of the first clip in a project, VideoStudio has no backward references to encode the redundant frames to pre-GOP exists so it produces none. This only applies to the first clip in the project as trimming any number of GOPs off a subsequent clip on the timeline does leave a pair of bad frames because a backward reference exists in front of the trimmed portion.

Because the frame used as backward reference to encode the redundant frames is not their natural, closest reference, but rather one a variable number of frames back in the sequence, its macroblocks do not blend in harmoniously with the rest of the picture and look extraneous. Hence the scrambled appearance of the two redundant frames particularly when the original clip is trimmed at an I frame and, as a result, the post-GOP is zero frames long, the redundant frames belong to the trimmed portion and the spurious macropixels are from the last frame in the pre-GOP, which may have come seconds or minutes earlier in the original clip.

This last situation, which should be the least troublesome in editing mpeg files as it represents GOP-accurate rather than frame-accurate trimming, results in the most striking effects: a sort of flashback at the scene change usually underlying a trimming operation.

Unfortunately, these posts lack the formatting capabilities required to illustrate the previous explanation with tables clearly showing the changes undergone by the different frames and GOPs involved in a trimming operation.

Visually edited clips
The problem here is similar to that faced when trimming a clip. Unlike cut points on both sides of a trimmed portion, however, VideoStudio cannot smart render a transition, filter, title, overlay or playback speed change as the process involves altering the visual appearance of some video frames rather than simply removing them and splicing the remainder. As a consequence, a video portion that has been applied a visual effect will never contain redundant frames; rather, the bad frames will appear immediately after the end of the visually altered portion. Why?

The process can be thought of as VideoStudio extracting the visually edited portion from the video stream, dumb rendering the required changes in the frames it contains and, finally, splicing both ends with the tail of the video portion preceding it on one side and the head of that following it in the clip on the other. Again, VideoStudio has no problem with the GOP preceding the edited footage (the pre-GOP), but fails rebuilding the joint on the other end (the post-GOP). The resulting bad, redundant frames appear in the same position relative to the edit point which is now the equivalent of the cut point in trimming operations.

Where does the edit point thus lie? Exactly at the frame immediately following the last touched by the visual effect as if the video clip were trimmed at the point where the effect ends.

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Post by Administrator » Fri Nov 03, 2006 6:42 pm

THE FRAME REDUNDANCY TEST

[quote="alosada"]This test will tell you whether your VideoStudio version produces redundant frames when smart rendering.

What do you need?
A clean source file
Because you will be checking whether VideoStudio smart renders properly, you will need a clean mpeg2 file in order to avoid introducing any artefacts into process.

A clean mpeg2 file can usually be obtained by encoding an avi file. VideoStudio 7, 8 and 9 come with some in their respective \\Samples\\Video folders. Unfortunately, those possibly best serving the purpose of this test (V17.avi in the VS8 samples folder and V12.avi in VS9) require version 5.11 or later of the Indeo codec, which is not installed by default. Those having VideoStudio on a CD can install the codec from it; those who don’t can download it here:

ftp://aiedownload.intel.com/df-support/ ... dinstl.exe

Please note that some users have reported running into problems with installer files not downloaded directly from the Intel site. In any case, the codec version needed to process the previous avi files might already be present in your system. You can check this by double clicking the Sounds and Audio Devices icon in the Windows Control panel and clicking the Hardware tab next. Double click the Video codecs entry and then click the Properties tab. If the list you see includes version 5.11 or later of the Indeo video codec, then you can use the previous samples as pre-source files.

If you don't have the Indeo video 5.11 codec on your machine and would rather not install it, you can use the V13.avi file that comes with both VS7 and VS8. This file was packed with the Cinepak Radius codec, so it should pose no problem.

An appropriate program to inspect the results
The easiest way to inspect the rendered file is by using a program affording smooth frame-by-frame browsing and accurate display of individual frames such as VideoReDo or VirtualDub MPEG2. If you don't have VideoReDo, you can download a 30-day trial version here:

http://www.drdsystems.com/VideoReDo

Also, you can download a free, fully functional version of VirtualDub MPEG2 at the following URL:

http://fcchandler.home.comcast.net/stab ... -MPEG2.zip

Neither program alters any crucial files in your system and both can coexist peacefully with any video editing software you may have installed.

Making a clean mpeg source file
Before starting, press the F6 key to display the Preferences dialog box in VideoStudio and make sure the small checkbox next to how message when inserting first video clip into the Timeline in the General section is CHECKED and that next to se default transition effect is UNCHECKED. Click the OK button.

The steps to be taken now depend on whether you will be using an avi file as pre-source or an mpeg file directly as source.

Preparing your source file from an AVI file
The procedure is as follows:

1. Press Ctrl+N to start a new project also, click the Edit tab at the top if you are using VideoStudio 7 and insert your pre-source avi file into the timeline (for example, by right clicking the blank timeline, selecting insert Video browsing to your chosen file, clicking its name in the Open Video File dialog box and, finally, the Open button).

If you insert one of the files that come with VideoStudio, right click its thumbnail on the timeline and select Properties you will see it contains no audio. Don't worry, it will still be usable for the purpose of this test also, if you wish, you can insert an equivalent length of audio from a sound clip of your choice into the Voice or Music track prior to rendering.

You can also use any other avi file of yours instead. Before encoding, however, reduce its length to a practical 5 or 6 seconds by trimming appropriate segments from the beginning and end.

2. Click the Share tab at the top of the window and then the Create Video File icon. Select Custom, click the Options button and then the Compression tab to select NTSC DVD as Media type those wishing to use PAL DVD can do so and replace the figures below by those in brackets in each case.

3. While in the Create Video File dialog box, click the General tab and make sure your Frame type is either Lower Field First (Field Order A in VS7) or Upper Field First (Field Order B in VS7); choose either otherwise. Click OK to return to the main dialog box, type in an appropriate name for your file (I suggest source mpg) and click the Save button. Once the file has been rendered, jump to step 4 below.

Preparing an existing mpeg file for use as source
You can use an mpeg file you are confident is clean as a direct source instead of an avi file as pre-source. What is a Clean mpeg file? Basically, an untouched captured file one that has been subjected to no visual editing (trimming, filtering, titling). You can confirm whether your candidate file is actually clean by having it parsed in VideoReDo, for example. Once you are sure it is, do the following:

A. Press Ctrl+N to start a new project and the Edit tab at the top if you are in VS7 and answer No if asked save changes to Untitled For easier operation, you may click the filmstrip icon on the left of the video track in the timeline to switch back to Storyboard View (or Storyboard Mode in VS7) if needed.

B. Insert your source file into the timeline. Answer Yes if asked Do you want to change the project settings to match the video's properties so VideoStudio can perform Smart Render?

C. Now, reduce the clip length to 5 or 6 seconds by trimming appropriate portions at the beginning and end, and render the remainder by clicking the Share tab first and the Create Video File icon then. Select Same as Project Settings and UNCHECK the box next to Perform Smart Render after clicking the Options button if you are using VS8 or VS9. Type in a name for your file (preferably something like Source mpg) and click Save. Once the file has been rendered, proceed to step 4 below.

Trimming and smart rendering your source file
Please take the following steps to obtain the file to be subsequently checked for bad frames:

4. Press Ctrl+N to start a new project nd the Edit tab at the top if you are in VS7 and answer No if asked Save changes to Untitled? For easier operation, you may click the filmstrip icon on the left of the video track in the timeline to switch back to Storyboard View (or Storyboard Mode in VS7) if needed.

5. Now, insert your source mpeg file into the timeline. If you followed steps 1 to 3 above, simply click and drag the thumbnail for Source mpg in the Video Library and drop it on the timeline; otherwise, right-click the blank timeline, select insert Video and navigate to your source mpeg file to open it. Answer yes if asked “Do you want to change the project settings to match the video's properties so VideoStudio can perform Smart Render?â€

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Post by Administrator » Fri Nov 03, 2006 6:42 pm

Topic: Audio Sync Issue...
This topic is several pages log so I will just pick out some of the meaty bits.
thecoalman wrote:
aconnell wrote:
Unfortunately, the process of creating an AVI from an MPEG is problematic as well with sync issues resulting in the AVIs.
Have you tried it by capturing AVI and using it as your source, no rendering etc. to right before you burn, I know you should be able edit mpeg, but VS8 isn't the only video editing app that has issues with MPEG nor is Roxio.

MPEG was never meant to be an editable video, AVI's such as DV or one using the huffy codec on the other hand were made for it. http://www.digitalfaq.com/capture/avivsmpeg.htm

I'll tell you how my work flow goes, I'm taking for granted I already have a AVI in sync on file. I'm using MSP but you can apply it to your apps. I set my project settings to exactly match my AVI, the reason for this is I like to preview a lot so the only encoding that has to be done is where I've edited. Once my edits are done I export as MPEG using whatever my final output is. that's it there's nothing left to be done to the video. It has gone through as little processing as it can. I import into DVDWS and create my disc, I use the "do not convert" feature and create a disc.

Doing it this way I have never had any sync issue....none. Another thing I would like to point out is that you didn't see too many people on hear having sync issues using AVI.
thecoalman wrote:
jwarner wrote:In my (humble) .

Why would you want to fill up your hard drive with information that says "a blue bit here, a blue bit here, a blue bit here, etc. etc." when it is far more effective to say, the next 2 million bits are blue.
This is similar to how video is compressed but that's not exacly how it works, it varies according to the compression method but basically a .jpg compresses by grouping like colors together. It in affect softens the image. With a large image a jpg compressed at 90% you would never know the difference between a bmp and a jpg unless you zoom in. Here's an example, the image in the left pane is a image from 3 megapixel camera, if notice the slider it's set at 90% compression which produces an image very near the original. If you look in the right pane you will see the image colors have changed. Where the quality loss comes in is when you keep recompressing, eventually all the detail is going to be loss and if you keep recompessing the affect is no longer a softening affect but produces blocks of color. This is the same thing as reencoding a mpeg, evertime you reencode you lose detail but it's a little more complicated than that....

Image

Here's an example of the same image compressed at 20%, the biggest thing to note here is huge block of a single color in the upper center part of the image in the right pane.:

Image

Where the issue comes in with MPEG is the way it's constucted, some frames take data from the previous frames which is one of the reasons it compresses so good, when cut one of these frames it needs to be reconstructed by the editor. This sometimes leads to audio sync when you cut on these frames....why I don't know. It really depends on the editor.

You can learn more about the differences between AVI and Mpeg here: http://www.digitalfaq.com/capture/avivsmpeg.htm

Encoding video needs much more processing obviously and early digital video cameras couldn't do it effectively so opted for an uncompressed format. Newer cameras don't have that problem so use compression (MPEG2 or MPEG4). Soon, I expect, all video cameras will record in MPEG4 format directly to flash media so there will be more more mechanical nonsense to deal with for storage.


I'll disagree with the mpeg4 part, mpeg4 was created to be a highly compressed format it to has the same issues as using MPEG2 as a source. The reason tape is used is because of it's storage capacity, you can only fit 20 minutes of DV-AVI on a DVD in addition to the fact of the speeds the DVD would need to be spun to record it, 16x drives might do it but I'm not sure. Remember though there is no difference between the file on tape compared to the one on DVD or any other media. If they wanted to they could record mpeg to tape as well but don't because there is no reason too. Shortly you will see another format with high capacity, blu-ray, flash whatever. They will still use a less compressed format though. And to further that you will still probably only get 1 hour since the new high definition TV's and cam's are coming on the market. :?
Just because Ulead seems to have a problem handling MPEG's doesn't seem sufficient reason in my mind to save a bunch of storage-hungry AVI's. Especially since, if your eventual goal is to burn a DVD, it will have to end up as an MPEG2 at some point!
Yes it aapears there is bug somewhere but VS8 isn't the only editor that has issues with mpeg. My curiosity is whether it's just prevalent when using mpeg or if AVI has the same issues too. I haven't seen anyone post that the same issue exists using AVI as source? Anyone?

Again MPEG is not for editing for more reasons that the audio sync ones. An extreme example but here's the difference http://phpbb.ulead.com.tw/EN/viewtopic.php?t=1428 :

3000CBR MPEG encoded from a DV-AVI, Lot's of macroblocking:
Image

3000CBR MPEG encoded from the 8000CBR MPEG, a real lot of macroblocking:
Image[/list]
GeorgeW wrote:it's supposed to pause and restart without glitches, but I've heard many experience a slight hiccup in the final captured mpeg. it works better when capturing from a dv tape, rather than when capturing from a device that is converting an analog source (see reasons here)
http://phpbb.ulead.com.tw/EN/viewtopic. ... ght=buffer

I agree that it appears the audio-sync issues come up alot more when the user is dealing with source videos other than dv .avi (i.e. could be mpeg, could be divx/xvid, etc...).

dv type-1 files seem to have less reports of sync issues -- I think I've also seen issues with longer dv .avi Type-2 files (greater than 20 minutes) -- because the audio is redundantly stored in the captured dv .avi file, and the process to capture to type-2 isn't perfect the longer the capture goes. Type-2 also takes a little more horsepower, so if your computer is "on-the-edge" of capturing dv .avi's without dropped frames, then try dv type-1 to see if it helps...
DVDDoug wrote:
This is a universal problem that should surely be addressed by the industry at large. Until further signs of advancement on this problem is indicated, I am giving it up!
I agree. The situation is ridiculous! Especially when you consider that the audio and video are multiplexed (interwoven) together in one file (with most video file-formats). There ought to be no-way to get them out of freekin?sync! And, in fact, the problems I had showed-up only after re-multiplexing?
Yet, NONE of these computer programs can!
Many people (including me) are able to capture and convert analog to digital without sync problems.


I don't recommend this, because it uses MPEG capture and editing? But, here's what works for me:

Capture with my Hauppauge card and the special software that came with it. (The Hauppauge card is MPEG only).

Edit with Womble (A special-purpose MPEG editor).

Author & burn a DVD with Movie Factory or DVD Workshop.

WORKS EVERY TIME !!!

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Post by Administrator » Fri Nov 03, 2006 6:43 pm

When all else fails do this.

VS & MSP: Fix for Out of Synch Audio/Video

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