I'm looking for a good frame viewer

[SCDVD]

I have a DVD that I want to take a screen grab of a frame that shows the result of a dropped frame when the video was captured from a DV camera. I am going to use this screen grab in a presentation to show one of the effects of dropped frames when capturing video. When viewing the video, it reaches a frame where there is a flash of multicolored blocks for a moment. When I step through it with Power DVD, the blocks don't show. I'm wondering if Power DVD just steps from one I-Frame to the next and the blocks might be on a P or B-frame. I need a viewer that will allow me to step it frame by frame so I can do a screen grab of this specific frame. Any suggestions?

[redwudz]

I use VirtualDub Mod for that. Just use the Left/Right arrows on the keyboard to step one frame at a time. Then you can save it as a snapshot or to the clipboard, depending on the format you want. It can also open VOBS.

[SCDVD]

Thanks redwudz. It worked like a charm.

[demonwarrior]

SCDVD what causes the multicolored blocks?

[SCDVD]

When a frame (or a partial frame) is dropped the missing video data causes various defects to appear in the video stream at that point when the video is played. One of the defects that can be seen is blocks that are missing or distorted when the video is played. This can look like small colored boxes that appear on the screen just for an instant when the video is played. This is sometimes made more apparant after encoding because the missing video data causes the encoder to encode without this data and one of the results can be macroblocks that are missing the video data and instead look like small colored squares on the screen when the video is played.

[demonwarrior]

how do u fix this?

[SCDVD]

It's best not to try to fix it. The only way to fix the problem caused by dropped frames is to edit out the bad frame(s) by cutting them out. It's much better to prevent dropped frames to start with.

When capturing DV video, the video data is not gated or "handshake" controlled. When the video data is being transfered over the firewire (or USB in some cases) interface, the host computer must be fast enough to keep up. If the system can't handle the video quickly enough, the frame(s) is dropped. In some cases, only part of a frame is dropped but this is almost as bad.

There are several things that can be done to improve the system's ability to handle the video data stream. These are:

1. Use a reasonably fast computer. It doesn't need to be a fire breather; 2GHz or better is sufficient. 1GB of RAM is sufficient.

2. Use a fast hard disc. 5.400 RPM is OK. 7,200 RPM is better.

3. IMPORTANT - Defragment the hard disc drive frequently and don't let it get too full. It's best to stay under 70% of the rated capacity. If the hard disc drive is fragmented, the drive has to spend too much time seeking from one block to another when writing the incoming video stream. If these blocks are not sequential, as is the case when a drive is fragmented, the non sequential seeks take much more time, and during these longer seeks, you are more likely to have dropped frames.

3. Make sure you don't have other process running in the background. Other running processes can interfere with the video transfer operation and cause dropped frames. These other running processes can either be legitimate applications or malware. The bottom line is that you don't want anything else running when doing a video transfer.

[demonwarrior]

ok whats the best way an the best tools to cut out the bad frames?

[redwudz]

What format? You can try VirtualDub Mod for that also. But it only outputs AVI type formats.

[demonwarrior]

ya but then i have to do it manually

[SCDVD]

ya but then i have to do it manually

You are not going to find anything that will automatically fix the result of dropped frames. As I said, the best thing is to avoid dropped frames to start with. Unless you have updated your system since you entered your profile information, you will continue to have a problem with dropped frames. Your computer just isn't fast enough to do a good job with video capture.

[demonwarrior]

i know,the prob is i got the source from someone else ,i think its a good idea if someone starts workin on a program that would automatically fix it,now that would be a challenge for the programmers

[demonwarrior]

o ya one more thing is there a way to insert frames?to make it more smooth?