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Ipod guru
03-07-2007, 08:58 AM
Hi all,
Share with me ur thoughts on any or all of the following:

1. Is a standard 80minute DVD meant to take 7 hours two convert with a default H.264 QVGA 768kbps stereo/128kbps profile? Or is there a way of speeding up this process?

2. On the topic of profiles, what on earth are the "flag" and "2 pass" functions?

3. I have only trialed one of my dvds using this program and the file size was nearly 600 megs and i predict that the current one i am converting will be around 500 megs. What ways if any can i reduce their converted file size? -
a) Perhaps choosing Mpeg instead of H.264 to see if it will reduce the file size much if any??
b) Reducing the resolution, if so how? - Playing with the width and height tabs or reducing the max resolution tab? (I understand picture quality may negatively be affected but im only planning on using ipod playback and not a bigger screen).
c) Cropping the top and bottom for widescreen dvds?

4. What is "padding"?

5. Does choosing a lower bitrate compromise quality to a noticable level for picture and sound if ur only planning on using ipod playback with FM tuned stereo sound?

6. Last but not least what exactly is bitrate?

Sorry for the lengthly questions but im anal and cant stand using something when i dont know exaclty what im doing.

Sketch
03-07-2007, 09:24 AM
1. Not on a relatively recent machine, no. If you want to speed up processing try a 1-pass with no/few flags.

2. http://www.redkawa.com/forums/showthread.php?t=526

3 & 6. The biggest determination of filesize is bitrate, which represents how much video/audio data is being processed per second. Bitrate * time = filesize. MPEG-4 won't make the file any smaller and will likely lower video quality at the same bitrate. Best to lower bitrate and set a resoultion manually (within settings).

4. The opposite of cropping. Cropping is cutting off a section of video to remove black space and/or fit a certain resolution spec. Padding is adding black space to fit a certain resolution specification without stretching/compacting the actual video.

5. Depends on how much you're lowering it by and what is noticeable to you. Sorry to be vague, but it's a very subjective issue.

Hope this helps. You might want to check out doom9.org for a lot of conceptual basics. It's a great resource.