question on capturing and compressing

[3390]

a while ago, i bought a capture card.. i haven't had a lot of time to play around and experiment with it..

i was hoping to capture some of my homevideos and burning them to dvd.. the problem is, the vhs tapes are all prolly either 5-6 hours long. i know that a lot of people prefer quality over quantity. however, i was hoping to be able to squeeze in the entire tape onto the dvd since i didn't want to have to split the videos into 2 disc. not that i mind using an extra disc, but bc i want everything to be together.

anyway, i realized that it goes by the file size.. and to my surprise, a 5 minute video is already 240mb.. 1.5 hrs would be close to the capacity of a dvd-r.. is there anyway i can compress the video?

btw.. it was captured to mpg format.. when i played it on windows media player, there is an extremely loud static sound that you can barely hear a word from the video.. anyone know why this is happening?

[jagabo]

To put six hours on a 4.3 GB DVD you'll have to use a bitrate around 1500 kbps. You'll have to use 352x240 (or 352x288 PAL) at that low a bitrate.

[3390]

if i was to do it at so low bitrate, would the quality be really bad? how can that be done? i mean, do i have to specify the bitrate at the time i'm capturing it?

what if i burn 4 hours to a dvd? what bitrate would i need and how is the quality?

btw, i need to add menu, etc.. fyi..

[Nelson37]

Filesize determined by bitrate. If doing real-time compression, then, yes, you will need to specify the bitrate at time of capture. A bitrate calculator will be helpful, but be aware that most cards do not adhere strictly to specified bitrate (menus and extras are minimal size) which brings me to:

Precisely what capture card are you using? Filling out your profile would be helpful.

The audio issue could be many things, check sound output while viewing with same connections, trace the problem back. Probably a place of contact between connectors which should be seperated.

You can put as much time on a DVD as you wish. The more time, the lower the bitrate. The lower the bitrate, the worse the quality. What is acceptable is a question only you can answer, asking for recommendations is a waste of time. The answer will be somewhere between 1 and 10 hours. There is NO answer that is correct, there is NO answer that is wrong. It is solely and completely a judgment call.

With the 6-hour tapes you have, you are going to experience issues getting this done with decent quality as it is.

[jagabo]

Also keep in mind that VHS tape is a very noisy medium, especially at the slower recording speeds. Noise makes it much harder for MPEG to compress, leading to more macroblocking.

[3390]

i have the adaptec videoh pci card (avc-2010).. i captured using it's supplied software "sonic my dvd." i was able to capture video and audio, but maybe i didn't set the settings correctly.

i also tried using nero to capture, but when i stopped the capture, an error message pops up. i tried looking for the file, but don't see it anywhere, do i doubt it even captured anything..

i actually posted a message at that time.. https://forum.videohelp.com/viewtopic.php?t=301896&highlight=

since it's a long weekend, i want to play around with capturing again.. any inputs?

[jagabo]

That appears to be a hardware MPEG2 encoding card. Only a few programs work with those type of cards. You're often stuck using the software from the card's manufacturer. In terms of file size and quality it doesn't really matter though, the card is doing the MPEG compression, all the software is doing is saving the data to a file and displaying it so you can see what's going on.

The software usually has controls for frame size, video bitrate, audio sample rate, and audio bitrate. The settings are often disguised with names like "DVD (standard play)", "DVD (long play)", VCD, SVCD, etc. You can often dig deeper to find and set things manually. If you can't find the actual bitrates, try recording 5 minutes at each of the settings to get an idea what file sizes they produce.

In short:

file size = bitrate * running time

You have to include both the audio and video bitrates. And since the bitrates are normally expressed as kbits per second, you should use the running time in seconds. And since the result will be in kbits you have to divide by 8 to get kbytes. DVD has a max bitrate of about 10,000 kbps (audio+video). At that bitrate you can fit about 1 hour on a DVD. You can use a bitrate calculator to determine the exact values you should to use.

If these are precious home videos you should bite the bullet and record the video at a full 720x480 and 8500-9500 kbps (depending on the audio settings). This will only get you 1 hour per DVD but it preserve the most detail.

If you still plan on putting 6 hours on a single layer DVD you should look at VCD quality (352x240, 1150 kbps video). Bumping the video bitrate up to 1500 will get better picture quality and 6 hours will still fit on one DVD. You will be losing half the vertical and temporal resolution by doing this.

A good compromise would be to split the 6 hours between 2 DVDs. Since your source is VHS tape you can use a frame size of 352x480 without losing much real resolution of the video (VHS has low resolution horizontally). And at 3 hours you can bump the video bitrate up to 3000 kbps. This will look pretty close to the original VHS tapes.

One last issue: the quality of the VCR can make a big difference in your result. A good SVHS VCR (starting around $300) with a line based time base corrector (TBC) will give you much better results than a cheap VHS machine. If the tapes are in poor condition you may need a full frame TBC too.

[3390]

someone told me that since i want to burn the captured video as a dvd movie, the amount being stored on a dvd disc is based on the length of the movie. i am hoping to squeeze in abt 4-5 hours worth of video (many tracks) into 1 dvd disc.. how can i do it? the majority of the source would be from vhs since they have been transferred to vhs tape from camcorder. i've burned some of them to dvd (using a standalone dvd recorder) and i want to take them to my comp since i don't like the menu that the standalone recorder offered.

[jagabo]

file size = bitrate * running time

Use a bitrate calculator to determine what bitrate you need for the amount (running time) of video you want on a DVD.

https://www.videohelp.com/calc.htm

Your best bet for 5 hours of video on a single layer DVD is 352x480 (or 352x576 if you are in a PAL country) at about 1800 kbps.

[3390]

thank you very much for the calc link!

the duration is per disc right? how do i know what audio bitrate i should select from the drop menu?

but with sonic mydvd (the included software with my capture card), there is no option to select the bitrate. what kind of software (pref freeware) is compatible with the type of capture card that i have and that would allow customized setting of bitrate?

as i said before, i am new with video capture... i hardly have time to sit down in front of my comp. thanks!