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  1. Hi

    I have some old .avi files I made years ago from legacy camcorder tapes. The files are 14Gb per hour and I want to compress them for easier availability and to make dvd's.

    The source video quality is quite low and it's stored as .avi.

    Questions:
    1 - Should I "open" the avi container to see what format the video is stored as, and then choose the new codec to compress with, or is the source format irrelevant or auto-detected in most conversion applications?
    2 - Can I just use Handbrake to convert the .avi file with h.264 to a .mp4 on 'Normal' settings?
    3 - Compressing the files to a dvd friendly size and format, is it ok to go from h.264 in an mp4 container to a dvd, or does that involve more coversion loss?
    4 - I also have some Mini-DV tapes I'd like to transfer to my HD & DVD. is h264 a preferable format ?

    Thanks in advance for taking the time to look at and answering my post =)
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  2. The original codec is irrelevant (as is the original bitrate etc). The video is decompressed and the encoder just sees uncompressed video which it re-compresses. 14GB per hour is quite large. It's possible the original AVIs were created using a lossless encoder (hence the file size being so large as it wouldn't be able to compress as much as a lossy encoder).

    If you use Handbrake's High Profile preset, it uses the default settings for the x264 encoder. Handbrake's Normal preset uses faster x264 settings (although you can change it, the medium x264 speed preset is the default).

    AVI to h264 to DVD involves two lossy conversions and therefore potentailly more loss of quality. It'd be better to convert the originals twice. Directly to MP4 and directly to DVD format. You could use something like AVStoDVD for the latter.

    H264 isn't a DVD compatible codec. It's very well supported in MP4s these days (almost anything should play it) aside from a standard DVD player. DVD video needs to be encoded using an mpeg2 encoder and it's easier to use a program such as AVStoDVD which is dedicated to the task.
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  3. Member
    Join Date: Jan 2007
    Location: Republic of Texas
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    Originally Posted by hello_hello View Post
    14GB per hour is quite large. It's possible the original AVIs were created using a lossless encoder (hence the file size being so large as it wouldn't be able to compress as much as a lossy encoder).
    Actually, it sounds like they are DV-AVI videos, and are likely pristine, bit-by-bit captures of what was recorded on miniDV tapes (depending on how they were captured). If these videos have any importance to you at all, I suggest you get an external hard drive that you can dedicate to archiving, and transfer the original files over to that drive. Afterwards, you can encode to a more compressed format, like h264, for viewing. But don't discard the original avi files. They will always be good sources to go back to when you need to edit or encode again to a future format.

    Whatever format you encode to, it will never equal the quality of the original.
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