Capturing Resolution

[evilwarmaster]

I just used my DV camcorder to capture video off regular (non-HDTV) TV using RCA connections. The DV video is 720x480, but it seems like I read on here that I can size it down to 352x480 without quality loss. Is this true?

[yoda313]

Hello,
There may be SOME quality loss. That spec you gave is the half d1 resolution. But you wouldn't have to if your file size fits on a dvd-r. Even if it doesn't it might be easier to shrink it down after authoring. What IS your file size anyway(and are you trying to make a dvd)?
Kevin

[evilwarmaster]

It is one hour of DV video, so I could fit it on a DVD at either resolution. But if the quality loss would be unnoticeable I'd like to be able to fit more on the DVD at the lower resolution (I could decrease the bitrate at the lower resolution with less of an impact).

[yoda313]

Hello,
I don't know anything about dv camera settings but capture cards have multiple bitrate settings. You can usually choose a lower bitrate to get more time in less space (just like vcrs have ep,sp,lp modes). You can use tmpgenc and other programs to lower the bitrate but that takes time and practice. If its from a tape you can recapture the source at the lower bitrate (and keep 720x480 or reencode to 352x480). Your choice.
Kevin

[Richard_G]

Unlike analogue capture where you can choose the resolution, DV through Firewire is a simple file transfer. The resolution is fixed by the fact that you are using a DV camcorder and that is what is transferred to your hard drive. You can resize it once it is in your computer, but you cannot transfer at anything other than DV resolution.

[yoda313]

Hello,

Well, like I said I don't know much about dv cameras. I guess what I was getting at was can he change the RECORDING settings on the camera? If the RECORDING modes can change the bitrate for a longer record mode that would be an option for future sessions (ie longer recording at lower quality?).
Kevin

[bugster]

But if the quality loss would be unnoticeable I'd like to be able to fit more on the DVD at the lower resolution

Strictly speaking, the resolution has no impact on filesize (and therefore how much you can fit on one DVD). The only things tha affect filesize rea bitrate and playing time, nothing else.

Of course, if you use a low bitrate, you end up with less 'bits per frame' and so lower quality. So, if you lower the resolution along with the bitrate, the overall loss in quality tends to be less as the encoder has less pixels to work with, if you see what I mean.

For DVD, if you need to drop the average (or constant) bitrate below about 3500kbps, then that is when you should consider using 1/2 D1. This is only a guideline, the final decision is up to you.

[lenti_75]

[quote="bugster"]

Strictly speaking, the resolution has no impact on filesize (and therefore how much you can fit on one DVD). The only things tha affect filesize rea bitrate and playing time, nothing else.[quote]

that's right, the only thing is that, when you go lower on bitrate than 3500 then you have to lower the resolution, otherwise that starts to look like shit.

[MpegEncoder]

Hello,

Well, like I said I don't know much about dv cameras. I guess what I was getting at was can he change the RECORDING settings on the camera? If the RECORDING modes can change the bitrate for a longer record mode that would be an option for future sessions (ie longer recording at lower quality?).
Kevin

The RECORDING mode does NOT change the bitrate. It simply changes the spacing of the frames on the tape (puts them closer together). The resolution and bitrate are unchanged.

[bugster]

[quote="lenti_75"][quote="bugster"]

Strictly speaking, the resolution has no impact on filesize (and therefore how much you can fit on one DVD). The only things tha affect filesize rea bitrate and playing time, nothing else.

that's right, the only thing is that, when you go lower on bitrate than 3500 then you have to lower the resolution, otherwise that starts to look like shit.

That why I said:

For DVD, if you need to drop the average (or constant) bitrate below about 3500kbps, then that is when you should consider using 1/2 D1. This is only a guideline, the final decision is up to you.

[BSR]

Mainconcept Mpeg Encoder has a program that can transfer your DV from your camera and convert it to 352x480 on the fly.

On a regular TV you probably will not notice any loss of quality between D1 and Half D1. But on an HDTV you will notice a loss of sharpness, at least I did.

But thats the trade off to fit more per DVD.