Since I’ve now got the means to transfer my digital tapes to DVD I would like to know what the agreed optimum capture and burn settings should be before I start wasting a bunch of DVD’s trying to figure this out.
The ‘native’ capture rate of the tape seems to be 22mps. Way too much.
The optimum capture rate (as recommended by Windows) is 2.1mps. Way too little, it seems. Blocky imaging and poor color repro at full screen. 'Course I’m veiwing on a 17" LCD with the resolution at 1024x768.
If I change the setting to ‘Large Video’ format and let the computer and the video camera figure it out themselves it appears to be about 15mps. (I can do this since I have a large enough HD (250G) and a double layer DVD burner).
These (22mps, 2.1mps, and 15mps) can all capture at 30fps and with a resolution of 740x480 or 640x480.
What is optimum for ideal capture so the video looks as good on DVD as it did on the original tape?
(In the end I will be watching these on a regular TV.)
I’m a little confused by your question, Uncommon Sense. Are you talking about capture resolution and bitrate or final-DVD resolution and bitrate? The two can be very different.
For capture resolution and bit rate, I’ve been using the defaults of NTSC DV-format video, what you get from a mini-DV tape.
My impression is that Digital8 tapes actually carry video data in DV format as well, and what you get from your tape is identical in format to what you would get from a mini-DV tape.
When I was capturing from a friend’s Digital8 camcorder, I connected the camera to my computer by Firewire and simply imported the video into an AVI in default DV format (DV codec, NTSC resolution). (Computer: WinXP SP1) I stated by capturing from within Adobe Premiere, but later used the little tool DVIO for simple transfer from camera to computer.
Are you capturing from analogue? If so, I’m not certain what the best bit rates to use are–I’ve only used the defaults inherent in my mini-DV camcorder.
For final output bit rate for the DVD…
The total bit rate coming off a DVD is (I believe) 10.9 megabits per second. Of this, the video stream can be a maximum of, I think, 8.9 Mb/s. (I’ll have to check these figures at home in my copy of DVD Demystified).
When I make a DVD, I have to compress the source video files into MPEG-2 files before I author the DVD. This results in about a 10:1 data compression.
I get to choose the bitrate of the final MPEG-2 file. The default setting is for one stream of video at around 8 to 9 Mb/s; this results in around two hours of video on a regular 4.7-GB DVD. Once I reduced the bit rate to 4 Mb/s for a draft disc and was able to squeeze 4.5 hours of video (still at full resolution) on the disc, but it looked blocky at times and the colours were’t as good.
I recommend buying a bunch of DVD RWs for tests anyways–just get the ones (DVD-RW or DVD+RW) that your equipment can read.
Thanks Sunspace, I thought the OP was clear on the source.
The source is a digital Sony Camcorder with Digital 8 tapes as the medium.
I’m afraid to capture at the source bitrate because that would be 22mps and I would fill up the 250G hard-drive after just a few hours of video capture.
Q- what output compression format can most newer DVD players read? You mentioned MPEG-2, is that a standard?
And if the compression is 10-1 then 10 Gigs of captured video at the native D8 capture (at 22mps) would then be 1 Gig on the DVD, right?
So, logic tells me to try to capture at FULL (22mps) and then compress to MPEG-2 to burn, does that sound correct?
I could get roughly 3.5-4 hours of compressed video on the double layer DVD then? (8.5G [double layer DVD] / 22mps/10 = almost 4 hours of video)
Am I missing anything here?
How long does it take to compress video from AVI NTSC to MPEG-2 to fill an 8.5 G DVD? (with a 3.4GHZ P4, 1G of RAM and Win XP)
Both actually. What do I have to capture at to get the best compressed output on the DVD? I’m afraid to over-capture/burn because you get to the point of negative returns at some point, Picture quality on the Television is only so good, I don’t need to capture/compress/burn much more than the TV will allow me to see, right?
Holy pooh! I’ve had trouble posting this reply. Kept losing it to the dreaded new-page reply response timeout. Sigh.
Okay, thanks. I wasn’t sure whether you were capturing from analogue input.
All DVD-Video discs use MPEG-2 video files with a certain format. Accompanying audo can be, I think, AC-3, LPCM, or DTS. The video and audio files are multiplexed together with the DVD’s menu information, subtitles, etc, in a very specific way. If your DVD-authoring software claims to make a standards-compliant DVD, it must save to this format.
This is where my confusion came from. You are talking about full broadcast-quality uncompressed digital video, I think.
DV-format digital video is not captured with as high quality. DV-format cameras sample the colour infrmation only 1/4 as often as the brightness information, because the human eye has less resolution for colour than for brightness. Thus it starts with a lower base bit rate.
DV-fromat video is saved in a compressed format as well: full picture frames (I-frames) are periodically saved, and then subsequent frames are compared to them and only the differences are saved. I believe this results in about a 5:1 data reduction compared to uncompressed video sampled in the same way.
If you are importing DV-format digital video, the choices for capture bitrate, colour-sample bit depth, etc, will already have been made by the camcorder. I believe that these are standardised for the mini-DV codec.
Storage: I am storing an hour of DV-format AVIs in about 15 GiB on my hard drive. When transcoded to MPEG-2 files for the DVD, they took up around around 1.5 GiB, I think.
When the DVD is authored, the audio/video files are multiplexed and stored in 1-GB chunks. Accompanying index files direct the player among them, and there is a playback buffer to cover the gaps.
That’s a good time estimate, but for the wrong reasons.
I worked it backwards. When transcoding to MPEG-2 for DVD, you can choose the output bitrate at which the file will be played back in the DVD player. It happens that 2 hours at the ‘high-quality’ DVD video bit rate of 8.9 Mb/s adds up to about 4.7 GB, so 8.5 GB on a DL disc would be about 3.5 to 4 hours.
I seem to remember that compressing a 5-minute AVI to MPEG-2 took about half an hour to an hour on my Athlon XP 2200+. Your system should take less time. When doing a discful of stuff, I’d set up a batch job and let it crunch overnight. Work while you sleep!
