Why some captures of same tape fine, another distorted

[Theresa]

Hello--
I had been having problems capturing with Premiere Elements 2.0, so I tried out WinDV. The clip I captured looked fine, so I then captured the entire tape. I ended up, then, having two versions of one segment of the tape. One looks wonderful; the other is distorted. Why is that? Same program, same tape, same circumstances.

Thanks
Theresa

[edDV]

How was it distorted?

Would you post a still?

[Theresa]

Hi edDV!
By the way, thanks for all the previous advice! I'm making success in figuring it out.
By now you know I'm new at alot of this. I have a still in bmp. form I can show you. I need to figure out how to post it.

Thanks
Theresa

[FulciLives]

Hi edDV!
By the way, thanks for all the previous advice! I'm making success in figuring it out.
By now you know I'm new at alot of this. I have a still in bmp. form I can show you. I need to figure out how to post it.

Thanks
Theresa

One of the best ways to "grab" a video still is to use VirtualDubMod. It has a built-in function to take a still and either copy it to the clipboard (so you can import it into an image editing program) or you can save directly to a graphic file (you can pick from BMP, PNG or TGA with PNG probably being the best quality for posting it here ... BMP is not a format you can post here ... you can only post JPG, GIF or PNG image files).

Read this on how to post your JPG, GIF or PNG image ---> CLICK HERE

- John "FulciLives" Coleman

P.S.
A good free image editing program would be PhotoPlus 6.0 by Serif Software.

[Theresa]

Here is the picture . . .it's of my little boy vacuuming his room.

distortion.bmp

[edDV]

It looks strange for a DV capture. The disk drive was probably busy with other activity.

Do you only have one hard drive? If so make sure virus scan and other tasks are turned off while capturing. That is a possible cause of the lost lines at the top. Also the hard disk needs defragmenting especially if near full.

The wedge shaped distortion after recovery is more difficult to explain. It only happens on one field and looks like a mechanical camcorder issue.

[Theresa]

I have three drives--two internal and one external. The second hard drive is the one I do all my capturing and editing on--it is mostly empty and all are recently defragmented.
I try to make sure I'm not doing anything else while capturing and I shut down as many background programs as possible. I didn't turn off virus protection though. My first WinDV capture didn't have this distortion. Really strange.
Thanks again for your help!
Theresa

[edDV]

I have three drives--two internal and one external. The second hard drive is the one I do all my capturing and editing on--it is mostly empty and all are recently defragmented.
I try to make sure I'm not doing anything else while capturing and I shut down as many background programs as possible. I didn't turn off virus protection though. My first WinDV capture didn't have this distortion. Really strange.
Thanks again for your help!
Theresa

On second look at that picture, I'm convincing myself this is a camcorder mechanical issue. Both fields are affected at the top only. One field relocked quickly, the other did that wide horizontal shift then snapped back.

Could there be a gap in the recording at that point? Is there tape damage at that point?

One test would be to record a new test tape and see if the problem repeats.

[Theresa]

Hi edDV-
But then why did one capture not have this distortion? There wasn't any gap or pause in recording and since it captured ok in the one instance, I'm not sure if perhaps the tape was a little loose and one capture was tolerant and another one wasn't. I would try to record again with that camera, but since a fourth grader knocked it on the floor at school, it doesn't open anymore! Good thing I have a miniDV now.

Thanks

Theresa

[edDV]

What was the camcorder and how are you capturing to DV?

[Theresa]

It was Panasonic Palmcorder IQ--I bought it in '96. And I'm capturing via JVC HR-S9800U>>Datavideo TBC-1000>>Canopus ADVC 110>>firewire.

[guns1inger]

So the noise is from the analogue tape and being transfered through. That tallies with the image you posted.

[edDV]

It was Panasonic Palmcorder IQ--I bought it in '96. And I'm capturing via JVC HR-S9800U>>Datavideo TBC-1000>>Canopus ADVC 110>>firewire.

So many possible sources of error. Try bypassing the TBC and see if it happens. Do you see the problem with tapes recorded on the JVC?

[Theresa]

Thanks for all the imput everyone.
guns1linger, I agree. I think the tape might be stretched and some captures are fine and others show it's age.
edDV, I have the TBC disabled on the JVC, and I'll disconnet the TBC out of the capture lineup. I have never recorded with this VCR--I bought it just for transfering my tapes to DVDs.

Thanks again!
Theresa

[edDV]

Thanks for all the imput everyone.
guns1linger, I agree. I think the tape might be stretched and some captures are fine and others show it's age.
edDV, I have the TBC disabled on the JVC, and I'll disconnet the TBC out of the capture lineup. I have never recorded with this VCR--I bought it just for transfering my tapes to DVDs.

Thanks again!
Theresa

Trouble shooting usually works best by minimizing the issues and adding one thing at a time.

The AVDC to computer path is probably good but I'd start by feeding it with cable tv.
Next add the JVC playing a consumer tape.
Next add your old tape.
Next add the TBC to see if it improves.

See where things get bad.

[FulciLives]

You have a great selection of hardware and this is a popular "set-up" so there has been much talk about it.

What some people have found out is this ...

Most of the time you can use the TBC in the JVC as well as a stand alone TBC. However some tapes actually get worse when you put them through a TBC. So in some instance you use both ... in some instances you use neither ... and in some instances you use one or the other.

1.) Both TBC devices in use
2.) Neither TBC in use
3.) TBC in JVC on but no stand alone TBC
4.) TBC in JVC off but use the stand alone TBC

Generally speaking one of those 4 will work and as pointed out option 1 is not always the best option.

- John "FulciLives" Coleman

[Theresa]

Great advice, edDV & Mr. Coleman. I will follow this proceedure. It makes good sense. I'm continually amazed by what I don't know.

Thanks again for helping a noob!

Theresa

[vhelp]

I just did a field-separation, (using my imaging tool) just to see what
the distortion would reveal for each field. If it helps any, here they are.

Note, each image is 720 x 240 dimentions.

.
.

** TOP Field



** BOTTOM Field


-vhelp 4163

[Theresa]

Thank you, vhelp. That's really amazing. What program are you using to do that?

Theresa

[vhelp]

What program are you using to do that?

It is a part of an on-going programming project, for analyising
video and images. Actually, that feature was just added in today,
no thanks to this topic, because I wanted to separate the fields
for other analysis work, (and the tool didn't include this, yet)
so I implemented the feature, and a few minutes later, an new
addition to the tools affectiveness.

This is just some of the things I do, on the fly, during my reading
of these forums -- its a hobby, mostly.

Anyways.. virtualDub and AVIsynth can do this similarily in their
own way for their enviornment. You can give it go if you want.

.
.

VirtualDub: Video\Filters..\Add\deinterlace:[(o) Unfold fields side-by-side ]

In this case, they would be 1440 x 240, because the separated pieces are
scotched taped end-to-end.

.
.

AVIsynth: (requires a script)

First, you create a script using your favorite text editor, typing in
the following, and save as video.separatefields.avs like this:

AVIsource( filename.avi )
separateFields()

Next, you open VirtualDub and frameserve this video.separatefields.avs file
into it, and observe the fields. In this case, they would be 720 x 240 pixels.

-vhelp 4165

[bobkart]

Not to belittle your achievements vhelp, but for anyone wondering how it's done (the two posted pictures), it's just a matter of taking every other line of pixels and putting them into a separate new BMP file. Not bragging or anything but I could implement a utility to do that in les than half an hour using plain C code (no library support other than file I/O).

[FulciLives]

Not to belittle your achievements vhelp, but for anyone wondering how it's done (the two posted pictures), it's just a matter of taking every other line of pixels and putting them into a separate new BMP file. Not bragging or anything but I could implement a utility to do that in les than half an hour using plain C code (no library support other than file I/O).

1.) vhelp made such a utility ... you didn't.
2.) vhelp explained how to do it with other software.

vhelp is a long term respected member here and I don't appreciate your tone in this particular instance.

THINK before you POST next time.

- John "FulciLives" Coleman

[bobkart]

vhelp is a long term respected member here

I understand that which is why I made sure to point out that my post was in no way meant to take away from his contributions to both this thread and this forum.

My post was meant for Theresa in response to her "That's amazing!".

[FulciLives]

vhelp is a long term respected member here

I understand that which is why I made sure to point out that my post was in no way meant to take away from his contributions to both this thread and this forum.

My post was meant for Theresa in response to her "That's amazing!".

If this is true then you didn't need that last sentence in your post about "not bragging ..."

However I feel that last sentence was a "jab" and you can't convince me otherwise.

Just don't be a jackass.

- John "FulciLives" Coleman

[bobkart]

[Theresa]

Needless to say, I am very appreciative of the experience, talent and good intent of you all. I am very much the novice in this endeavor, and in need of the collective pool of talent this forum offers. vhelp & bobkart, edDV, Mr. Coleman and guns1inger --when I read the good advice and see the effort that went into this picture of the clip of my little boy, I am so grateful you jumped in to help. I'm definitely swimming in the deep end.

Thanks
Theresa

[edDV]

True that splitting fields isn't rocket science. Show your stuff by explaining why field 1 shows white at the top and field 2 shows black?

Then why field 1 H locked and field 2 took a field trip left then came back?

Strange stuff that is either tape transport related or that plus the TBC confused by the dropouts.

[bobkart]

Show your stuff by explaining why field 1 shows white at the top and field 2 shows black?

Then why field 1 H locked and field 2 took a field trip left then came back?

Nope, I don't have any of that "stuff" to show. So you got me there.

[jmkeuning]

Wanna know what's AMAZING? a two year old vacuuming!

And that he has a briefcase and a computer in "his room." What an over-achiever!

[Theresa]

Do I need to send you all to your rooms??

Ahem . . . this was my son's temporary room until I could finish his 'room'. Thus the briefcase. As far as the vacuuming . . . you can never start too early!! He was fasinated with the thing.

Thanks, guys!

Theresa