Is dropping 10 frames ok out of a 1 hour movie?

[davy19]

Out of 100,859 frames, I dropped 10.

Is that ok? I was reading on this forum where people always drop 0 frames.


Is my PC too slow? P3 866, 512 Ram, Win98se, Western Digital Special Edition 7200 RPM 80 Gb drive, using virtualdub, and Huffy codec


Thanks

[TenaciousJP]

The only way to tell if it's OK is to watch the movie you captured. If it looks good to you, then it should be OK.

10 frames doesn't sound bad.

[nick1977]

That is exactly the same as I get. About 1 in 10,000.
You can check my PC spec above, and it's not quite as good as yours.
I use AVI_IO and huffy codec at 352x576 YUY2.

If you have a WinTV Go card and Soundblaster soundcard, then I guess the drops are related to them, to keep in sync. God knows I've tried everything else!

That said, if anyone has any suggestions....

Nick

[KingJohn]

Out of 100,859 frames, I dropped 10.
Is that ok? I was reading on this forum where people always drop 0 frames.

Is my PC too slow? P3 866, 512 Ram, Win98se, Western Digital Special Edition 7200 RPM 80 Gb drive, using virtualdub, and Huffy codec
Thanks

Depends
If you play the movie on your computer there wont be a problem shown, if you try to edit the mpeg or convert to something else you may have a problem. If put on a VCD you may also have audio sync.

10 frames is something and nothing

[vhelp]

evening dayv19,

>> Out of 100,859 frames, I dropped 10.
>> Is that ok? I was reading on this forum where people always drop 0 frames.
In short, no. it's ok to drop a few frames an hour! It's ok!

Now, that said, I don't know if true or not that you can drop ZERO frames
an hour or ever. However, I remember complaining and making BOLD
statements that IT IS IMPOSSIBLE TO CAPTURE AT 720x480 AND NOT
DROP ANY FRAMES, OR EVEN CAPTURE!! he, he... That was then, this is
now. And, I CAN capture at 720x480. But, I don't think that you
can NOT drop a single frame. I would prefer NOT to drop
any, but hay, 10 really ain't so bad 8)

Even, w/ my DC10+, being a Hardware MJPEG cap card, it dropped
frames, ie 10 an hour. And, that was on my old pen 233 MMX.
I'm going to do some experimenting and testing w/ my old faithful DC10+
card (another issue about Line Noise... in another thread I started)
So, I can't wait. I finally I found it, so. . .

But, anyways, don't worry so much on a few frame/hr. Consitrate on the
Quality part, and encoding Quality.

Later.
-vhelp

[kinneera]

I'm fairly certain anyone who claims they capture with absolutely no frame drops is lying. Oftentimes, capture software (VirtualDub among them) will intentionally drop frames to maintain sync. Tape sources generally will also have some timing errors which will result in a drop here and there. 10 out of 100,000 (or 0.0001%) is definitely not anything to worry about.

[vhelp]

thanks kinneera,

I forgot about the vdub issue w/ audio sync and dropped frames.

-vhelp

[tww1]

Well i wish i could only drop 10 would make me very happy. I have a XP1700,XP1900 with 512 DDR ram 7200 WD 120 HD in both mechine and i normaly drop any where from 50 to 70 frames in a two hour movie help.

[vhelp]

davy19, and other. . .

tww1,
first, I getting at capturing from Satalite, and the lack of THAT many
dropped frames in my captures, even at 720x480. However, EVEN when
I capture from VCR (store bought VHS movies) I don't have wild frame
drop. I still have approx 10 an hour (give or take, as I always have
something else opened while capturing on THIS pc, ie Internet and
IE, and a dozen of IE windows opended) I'm usually trying something
out real quick, and so, I capture while everything else is up and
running. Even if its VHS. Sorry if that hurts!

I don't know what you issues are, cause you didn't specify, ie
your source, resolution, capture card, etc. But, to

My harddrives are slower tan yours, 5400rpm I think. I'm just greatful
that I CAN capture at 720x480 these days. Heck, I'm happy as a boy w/
a first crush But, I know the frustrstrations. I have an issue
going on right now, w/ Line Noise in my VCR captures that I've
ben living with for some time, but am getting pretty fed up with them
now, and hence the thread I started on it. I've ben at it for a week
now. Maybe I'm slow, but I have lots of things going on, plus, i've
ben staying very late at work (till 9am - 10pm) and that has ben a
ware and tare on me all this week. So, maybe that's to blame in my
still not finding a solution to my VCR captures and Line Noise
issues.

But, the capture cards I use are ATW and WTGO. And, capture at
720x480 w/ approx 10 frames an hour, maybe more.

davy19, and others:
For those who are having frame drop issues, you may be able to reduce
them by usin this techequie I use (don't know why I forgot to mention
it earlier) But, it has a direct relation to my solution w/ the
SLOW smartripper I used to get last year, ie 1x or 2x. But after my
mod in BIOS, I get up to 9x ( or more? ) This was on my old system,
T-Brd 900MHz, but on this system, it's just the same speed to 9x in
smartripper. Anyways, as to the capturing issue, it seem to help
(magically speaking) that if I went into my BIOS and. . .
* find your CDROM/DVDROM UDMA command and DESABLE BOTH of them!
* reboot
* and try your captures again. May work, or not. or worse.
But forme, it works beautifully! I rip at 9x (fluctuates) and capture
w/ approx 10 framedrops/hr

Try it out. Can't hurt too much, right?

Good luck!
-vhelp

[bbb]

I use Studio 7 capture software (with code by the AVI_IO author--Markus Zing) and a DC10+ capture card.

One thing I noticed about my 30 Gig ATA33 HD (which also holds my OS) is that it slows down as it is being filled. It has a sustained capture rate of about 32 MEGs/sec when it is 5% full then it drops to about 12-15 MEG/sec when it is 80-90% full.

On a good day I drop 3 frames/hr. On a bad day I get 9 frames/hr. It's no big deal--not noticeable at all on playback in AVI form or in encoded MPEG form.

I used to capture to my secondary 40 Gig ATA66 HD--which drops even fewer frames. At times getting 0 dropped frames/hour. It's currently filled with files which are in need of being stored to cdr.

Advice: Live w/ 10 drop frames for now but try to keep your HD as empty as possible. Then save up for a second 7200 rpm dedicated harddrive--the bigger the better.

[davy19]

Thanks everyone for their advice.

I just started to get into VCD, and learning a lot real quick.

I did forget to mention I am using a WIN TV Go card I got for $30 last year, and do have a SBLive card if that helps.

The resolution I choose was 352x240 which is what it said in the guide on this site. I dont know if I should even try higher resolution.

[tww1]

Thanks for the respond i am useing a WinTvGo Card captureing with VD at 352x240 only doing VCD ok quility for me. Recording from Ditigal Cox Cable.

[vhelp]

FYI: . . . .

BIOS'wise. . . but, . . .
----------------
not to sound like I'm rubbin it in and all, but I just finished doing a sample
capture from VHS via my SIMA stabalizer and (running an experiment)
and All's I had was 1 frame drop at 720x480, w/ ~26 apps up and running:
* well, 21 IE browswers of differnce URLs, ie
* VCDhelp/Pinnacle
* and 4 other FORUMs of various driver content
* plus other Google.com hits, etc.
* and a F3 experorer search of files
* and dos app window
* notepad
* Netscape mail (set to 1 minute polling)
* 3 exploer folders
* 1 Explorer dir
* vdbub capping from VHS at 720x480
* oh, and did i say, I was D/L'ing 5MB a file all the time?

That's w/ my BIOS mod on my:
* ECS K7S5A motherboard w/ 256ddr
* ATW (ati-tv wonder pci)
* 20g 5400 rpm
* vdub set to 720x480 - 2 minute capture (given the above list)

-vhelp

[KingJohn]

I'm fairly certain anyone who claims they capture with absolutely no frame drops is lying. Oftentimes, capture software (VirtualDub among them) will intentionally drop frames to maintain sync. Tape sources generally will also have some timing errors which will result in a drop here and there. 10 out of 100,000 (or 0.0001%) is definitely not anything to worry about.

Then there must be a lot of liars around this forum then, just because you drop frames does not mean that everyone else does. Most people don't use the software that comes with the card, and push the capture beyond the limit, or have a under powered machine. I use the original software and capture with DivX 3.11 Alpha with "NO" dropped frames.

If there is any frame loss, then changes are that those you have copied will have junk frames either side of the lost frame and will cause a problem with editing

[kinneera]

Well for those of us who care enough about quality to know not to capture straight to Divx, the AVI capture formats we use don't establish any temporal encoding dependencies. Thus dropping a frame is going to have absolutely no impact on surrounding frames, and smart capture software dropping the occasional frame is entirely normal and often beneficial as it can be correcting for timing inconsistencies in the source. If you're not dropping frames, congratulations, you must have a very good source or your software simply doesn't tell you that frames are being dropped underneath a certain threshold (MMC for one behaves this way). In any case, it isn't really worth arguing over since the original question has been adequately answered, in that dropping 1-thousandth of one percent of the footage is not going to have any practical impact on the final product.

[KingJohn]

Dropping any frames does have an impact on editing, I see many post on people capturing to all sorts from AVI to Mpeg 1/2 and anything else that’s available that may help them capture without loss.

Most start the post with saying "It plays fine and is good quality" fine... I have no argument that 1 in 1000 will have any impact at all on playback, but when it comes to editing those files, that’s when the trouble starts.

1 frame here and there will upset programs like TMPGEnc which may even abort on the conversion. If the capture is to mpeg 1 for VCD then DVD players may skip and can cause sync problems.

Judging by the number of posts on this subject, frame drop is a big problem. This is based on the "Thousands" of people that have posted with frame drop problems

I have a cheap basic card, capture to AVI produces no dropped frames, capture to Mpeg 1 produces better video but dropped frames, So like many I have chosen something that works best for me.

The quality of the capture is not high, however there is nothing wrong with DivX at all, a DVD to DivX produces extremely high quality.

I don’t think my software lies either

[kinneera]

Dropping any frames does have an impact on editing, I see many post on people capturing to all sorts from AVI to Mpeg 1/2 and anything else that’s available that may help them capture without loss.

1. MPEG and Divx are not lossless.
2. Both employ temporal (time-axis) compression techniques, so you are right a missing frame can cause editing problems. Unfortunately, this is not true during capture, as the frame drop occurs before the realtime encoder handles it, which means from the encoder's perspective the frame never existed at all. Thus the temporal dependencies will be based solely on the frames that were captured so it won't cause problems in that respect. It can, however, cause a/v sync problems.
3. Lossless AVI generates no temporal dependencies between frames. A frame drop during capture under these circumstances will never cause editing problems because in such an AVI, every frame is a key frame. Again, though, a/v sync problems can result. And also again, some software will actually intentionally drop frames to maintain sync when it determines that synchronization is being lost.

1 frame here and there will upset programs like TMPGEnc which may even abort on the conversion. If the capture is to mpeg 1 for VCD then DVD players may skip and can cause sync problems.

It sounds to me a lot like you're experience is limited to Divx. A bad frame in a Divx will upset programs like TMPGEnc. A bad frame is different from a dropped frame during capture, which will not. See #2 above. IMHO direct capture to VCD MPEG1 looks terrible anyway, but I guess that's a matter of personal preference.

Judging by the number of posts on this subject, frame drop is a big problem. This is based on the "Thousands" of people that have posted with frame drop problems

Fair enough, but as has already been agreed upon 10 out of 100,000 doesn't qualify as a big problem.

I have a cheap basic card, capture to AVI produces no dropped frames, capture to Mpeg 1 produces better video but dropped frames, So like many I have chosen something that works best for me.

AVI should look much better if its lossless or uncompressed (i.e. NOT divx). But that's a whole different discussion.

The quality of the capture is not high, however there is nothing wrong with DivX at all, a DVD to DivX produces extremely high quality.

If you're capturing from DVD, then I will concede you may actually get away with no frame drops unless your CPU is too slow. But it doesn't make any sense to me to perform an analogue capture of a DVD. A tape on the other hand often does not have very good timing signals, which results in frame drops, both intentional and uninintentional. Also, any Divx that is extremely high quality (which is certainly a relative term here) was almost certainly not captured realtime.

Cheers.

[KingJohn]

1. MPEG and Divx are not lossless.

Why make this comment, it has nothing what so ever to do with the discussion of frame drop, you now presume that everyone is capturing with all the same settings, and everyone is saving with a lossless codec.

They are not, most don’t want the huge size, no matter what !, and so capture to DivX with the best they can do.

2. Both employ temporal (time-axis) compression techniques, so you are right a missing frame can cause editing problems. Unfortunately, this is not true during capture, as the frame drop occurs before the realtime encoder handles it, which means from the encoder's perspective the frame never existed at all. Thus the temporal dependencies will be based solely on the frames that were captured so it won't cause problems in that respect. It can, however, cause a/v sync problems.

So now you say we have 25 frames at one instant, but 24 at the next / per second, and does that "Real time encoder" think that the last frames up until the last key frame never existed either. Or did it make every frame a key frame in the Mpeg 1 capture also.

3. Lossless AVI generates no temporal dependencies between frames. A frame drop during capture under these circumstances will never cause editing problems because in such an AVI, every frame is a key frame. Again, though, a/v sync problems can result. And also again, some software will actually intentionally drop frames to maintain sync when it determines that synchronization is being lost.

Then I suggest you tell all those people who are editing captures, Mpeg 1, Mpeg 2, DivX, Huffy that are having problems, that there is nothing wrong with the capture they made and give it up !!

It sounds to me a lot like you're experience is limited to Divx. A bad frame in a Divx will upset programs like TMPGEnc. A bad frame is different from a dropped frame during capture, which will not. See #2 above. IMHO direct capture to VCD MPEG1 looks terrible anyway, but I guess that's a matter of personal preference.

Actually your wrong again, however despite my own experience I actually read the many forum messages, and what problems people have. I can see what they are doing, and I can also see when they have fixed the problem, that sort of experience will be worth more than one persons personal experience. And a bad frame, is a frame that has not been captured correctly, so you are now saying that its ok to drop frames and its also OK to have bad frames, sounds like your standard is very low when it comes to capturing.

Fair enough, but as has already been agreed upon 10 out of 100,000 doesn't qualify as a big problem.

Yes provided the person knows how to deal with it. Posting messages saying that its perfectly acceptable to loose that many frames, will mean the person wont blame this as the source of the problem.

AVI should look much better if its lossless or uncompressed (i.e. NOT divx). But that's a whole different discussion.

Yes, but the size is not expectable, so there for its not used by many

If you're capturing from DVD, then I will concede you may actually get away with no frame drops unless your CPU is too slow. But it doesn't make any sense to me to perform an analogue capture of a DVD. A tape on the other hand often does not have very good timing signals, which results in frame drops, both intentional and uninintentional. Also, any Divx that is extremely high quality (which is certainly a relative term here) was almost certainly not captured realtime.

So you assume that everyone has all the necessary equipment when they first come to this forum. In fact many people don’t eve have a DVD player. If they already have a capture card, why not try and use it, and see what can be done. Capturing from a DVD via composite/audio in does produce very good results, obviously not as good as a DVD rip, however if the person rip's the DVD then goes on to convert it to a DivX with very low bitrate, then I guess the capture that was also converted to the same, would pretty much look the same.

And the majority of captures are not from a DVD anyway, but from a TV source or tape. With excellent results coming from a Digital TV signal
closed

[Nelson37]

KINEERA, re MMC and Frame Drop - are you saying that the percentage indicator will say 0% with some frame drops (as it will), or that when in Frame Count Display, the "Dropped Frames" numeric value reported is inaccurate? Meaning, it could say 10 when you have dropped 20?

BTW, I always get an initial drop of 10-12 frames, then none after that. SBLive and one onboard audio identical, 2nd board with different on-board audio did not drop initial frames. I assume this to be startup synch problem, all three would sometimes drop to 0% with dropped frames, although numeric counter always showed initial 10-12.

[Nelson37]

Forgot to respond to the initial question. I personally shoot for 0 drops, 3-5 in an entire movie is very annoying, mainly because I know it is possible to eliminate the problem.

I cap hi-bitrate MPEG-2, IVTC, and re-encode. Best mix of excellent cap, able to cap 3 to 5 movies before encoding, about 60 minutes per CVD, 50 for SVCD. With AVI, I get occassional spurts of drops, sometimes 2 hours no drops, sometimes 30. One movie and my HD is full. Final encode no better than from MPG2 cap, IMHO.

[kinneera]

1. MPEG and Divx are not lossless.

Why make this comment, it has nothing what so ever to do with the discussion of frame drop, you now presume that everyone is capturing with all the same settings, and everyone is saving with a lossless codec.

They are not, most don’t want the huge size, no matter what !, and so capture to DivX with the best they can do.

It was actually in reference to this: "anything else that’s available that may help them capture without loss" but I will admit I think I misinterpreted your use of the word loss there. Most people don't want the huge size in the end, but most people who are serious about video editing end up doing lossless capture to AVI for editing and then encoding non-realtime, in particular because of editing problems with other formats that are unrelated to dropping frames during the actual capture process.

So now you say we have 25 frames at one instant, but 24 at the next / per second, and does that "Real time encoder" think that the last frames up until the last key frame never existed either. Or did it make every frame a key frame in the Mpeg 1 capture also.

You're missing my point. What I am saying is that the frame is dropped at the hardware level, which means its gone before any encoder looks at it. (Even if the encoder is responsible for the drop, that very fact means that it is of course going to handle the situation without corrupting the stream unless it is a very poor encoder). The encoder ends up seeing a stream of perfectly valid frames, its just that there's one less of them than actually existed. Thus the framerate remains constant and in the case of MPEG, all the frames are encoded as if the missing frame never existed, i.e. if the frame after whichever one was dropped gets encoded the way the dropped frame would have been encoded, be it I, P, or B frame. This doesn't introduce any editing problems that aren't already inherent to MPEG encoding, thus frame drops are not related to editing problems. Corrupted frames, which are an entirely different matter, can cause serious problems but typically are only encountered in incorrectly encoded Divx files.

Then I suggest you tell all those people who are editing captures, Mpeg 1, Mpeg 2, DivX, Huffy that are having problems, that there is nothing wrong with the capture they made and give it up !!

If they are attempting to edit MPEG1,2 or Divx, I never claimed they wouldn't have problems during editing. That's because removing frames from a video stream that is encoded using methods that create cross-frame (temporal) dependencies (which all of those formats do, with the exception of I-frame only MPEG capture) does cause problems. But again, this has nothing to do with dropped frames, which were lost before any encoding ever took place.

And a bad frame, is a frame that has not been captured correctly, so you are now saying that its ok to drop frames and its also OK to have bad frames, sounds like your standard is very low when it comes to capturing.

No, a bad frame - meaning the existence of data improperly encoded - is a very different beast from a dropped frame - which is the absence of data that was supposed to be there. See the above points. And no, my capture standards are very high, which is probably one of the reasons I have very few problems editing and encoding them.

Yes provided the person knows how to deal with it. Posting messages saying that its perfectly acceptable to loose that many frames, will mean the person wont blame this as the source of the problem.

There's nothing to "deal" with when that few frames are dropped. It's immaterial, especially if they're being dropped on purpose by the software.

Yes, but the size is not expectable, so there for its not used by many

Yes, the size of an AVI capture may not be perfectly predictable, but the size of the final output after encoding to a compressed format is just as predictable as if it was captured straight to the compressed format.

So you assume that everyone has all the necessary equipment when they first come to this forum. In fact many people don’t eve have a DVD player. If they already have a capture card, why not try and use it, and see what can be done.

This is beside the point really. All I was trying to indicate was that a DVD has very good discrete timing signals that make the probability of frame drops due to timing errors (common on tapes) a low probability.

And the majority of captures are not from a DVD anyway, but from a TV source or tape.

Which is precisely why I was trying to say that frame drops are very typical from these sources. Devices known as time-base correctors exist largely for this very reason.

KINEERA, re MMC and Frame Drop - are you saying that the percentage indicator will say 0% with some frame drops (as it will), or that when in Frame Count Display, the "Dropped Frames" numeric value reported is inaccurate? Meaning, it could say 10 when you have dropped 20?

Used to be that MMC wouldn't even report frame drops sometimes (I think some people even considered it a bug and complained accordingly). Perhaps that has changed, but I have since stopped using it since it didn't meet my needs anyway. I will defer to you on its current behavior.

[kwag]

Anyone who want's to capture without dropped frames, needs something like this: http://www.videoguys.com/medea.htm
This is the kind of thing you use to capture RAW or MJPEG. But then, that's pretty expensive for us toying around.

-kwag

[vhelp]

Well, I finally found this post, where I foolishly ranted about how its
IMPOSSIBLE to capture w/out framedrops. I stand corrected. YOU CAN.
I may be able to capture w/ Huffy and no frame drops, but that is sort
of rare. But, if I capture uncompressed, THEN I get ZERO framedrops.
I'm talking about capturing at 720x480.

Course, Now that I have my ADVC-100, who cares. And, to boast, I have
my trusty DC10+ my WTVGO and now my ADVC-100 all working together w/out
issues. My process is finally getting better (if not already)
But, one must say, at a cost. It took some spending to get where I
am today. Well, I just wanted to say that.

What I have found, was that your system has to be properly tuned in
order NOT to have any framedrops, and of course, having a faster CPU
definately helps. The main keys are:
* proper driver installation
* IRQs worked out
* Source device ie, VCR, Satalite, ...and,
* Source material's quality. ie, bad quality like VHS wont help.

Now, I'm sure that others here too, have descovered this ZERO framedrop
can be achieved. I was just playing catchup to my OLD post or statements
here on the "it is impossible ot capture at 720x480 and not drop any
frames, or even capture!!" statement. Ha, ha, what a fool. Well.. we
live and learn, and grow.

Greetings all.
-vhelp

[Kingnog]

Stop yelling! My heaaaad hurts!

[Mirror_Image]

I either drop no frames, or about a dozen frames in a row at the very beginning of the capture, then it's smooth sailing from then on. I trim that half-second off the front end, and everything is peachy

[vhelp]

sorry.. didn't realize I was yelling

Mirror_Image,
good to see you around - miss those antics of yours.

-vhelp

[SatStorm]

With a Duron 1200, a WD 7200rpm HD, win TV primio FM, Hercules game furtissimo 2 sound card, Huffyuv or Pic Video, I have about 3 - 5 frame drops per hour. capturing @ 352 or 720 X 576.
Frameserving those files with VDUB to TMPGenc plus, eliminates any possible audio synchronisation problem.
The source can be VHS from a VCE with TBC or Sky Digital (analogue capture from a satellite digital receiver, using the The SCART)

Zero drop frames are depenting a lot from the hardware! For example, capturing with an athlon xp 1700+, asus 7700 GTS deluxe VIVO and Hercules game furtissimo 2 sound card, using asus digital vcr and asus avi codecs, @ 720 X 576, with a WD 7200rpm HD, give me no frame drops. On the same machine, capturing with win tv primio fm, Huffyuv and vdub @ 352 X 576, give me about 5 drops per hour.

Anyway, the bottom line is 1 frame per 5 minutes ain't noticable and if there are some probs with the encoders or issues about syncronisation, there is always the TOP solution to prevent bad stuff: Frameserving.