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Fingers
23rd November 2009, 07:30 PM
I knew it sounded too easy to be true.

Believe it or not I have only just bought an ipod (its still in the box for the kids for Christmas) and I was using handbrake to put some of their DVD's into the ipod format ready to go chrissy day.

I also have Eye TV, and I exported some things from it to an ipod format to go on their ipod.

Although I thought I managed this with ease, I am a bit confused with the Quality?

I really don't have all that much content, so I was trying for a High Quality, rather than volume of content.

I have tried different options, but what I thought was better quality, to my eye appears inferior.

I did a test case.....I did the same video twice......once as 640x360 and again at 720x404....I had assumed the 720x404 would be superior, however to my surprise the 640x360 appeared cleaner crisper sharper to the eye (from my 50 inch Plasma that my Mac Mini is connected to).

The thing I noticed that the bit rate was much higher on the 640x360, but at no stage did either HandBrake or Eye TV ask me about bit rates?

Appreciate anyone's feedback on what specifications they use when using handbrake or Eye TV to convert to video to ipod format. (mp4 or H264?)


cheers............Tony.

Fingers
23rd November 2009, 07:31 PM
Bugger....I've only just posted this....did I get the correct section, or should this thread have gone in the ipod section?

sorry?

ZacDavies
23rd November 2009, 11:01 PM
I too am interested in this..

..been thinking of converting my large .AVI movie collection (all.. legal.. cough), what's the best MP4 format (least lossy) and easiest way to achieve it.. still Handbrake?

scarbrow
24th November 2009, 02:19 AM
I did a test case.....I did the same video twice......once as 640x360 and again at 720x404....I had assumed the 720x404 would be superior, however to my surprise the 640x360 appeared cleaner crisper sharper to the eye (from my 50 inch Plasma that my Mac Mini is connected to).

The thing I noticed that the bit rate was much higher on the 640x360, but at no stage did either HandBrake or Eye TV ask me about bit rates?

My knowledge of how the encoding process works isn't brilliant, but this is probably the simplest way to explain it.

640x360=230400 pixels
720x404=290880 pixels

The overall difference is about 20% in pixels for actual viewing size, but if you look at it as width vs height there is roughly 10% shrinkage (360/404=~0.9). Assuming the encoding is done at the same bitrate, the smaller resolution is able to hold more detail.

Also when encoding with x264 in handbrake, it was mentioned somewhere that there is better video compression when the dimensions are multiples of 16. So sometimes cropping the dimensions while preserving the aspect ratio can improve quality (or was it file size?) even more.