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  1. Member
    Join Date: Feb 2012
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    Hello

    This is my first ever post on a forum so I hope I am on the right section of the site, here it goes:

    I have about 100 vhs and s-vhs tapes which i converted to DVD a while ago. I now need to covert them to H.264 for use with an analysis program. Do I need to go back to the vhs and svhs tapes and capture them to convert to H.264, or can I go straight from the DVD to H.264. If i use the DVDs rather than the originals will it greatly affect the quality?

    any help greatly appreciated

    kind regards

    Jeannine
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  2. Member 2Bdecided's Avatar
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    What analysis program?

    You'd normally convert to save space, or (if starting from scratch) to achieve slightly higher quality.

    How did you convert to DVD in the first place? How many minutes/hours did you fit onto a DVD?

    Cheers,
    David.
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  3. It's also worth asking, are these H.264 files just a "one time" sort of deal, or do you plan on these being your "master copies" from this point forward? If you're making new master files of important videos that you might have to transcode again in the future, it may be wise to create them from the original source (VHS/S-VHS) even if your DVD's are high-quality...but if it means capturing to a PC, it will come at the cost of many headaches. Just so you're aware, capturing to the PC instead of using DVD recorders can be an expensive, time-consuming, and error-prone process. You can ultimately get better quality in more ways than one* if you work at it, but pretty much every VCR, TBC, capture card, etc. has quirks/issues that need to be addressed, possibly with more quirky hardware. Good DVD recorders manage to avoid most of this mayhem, and you can get decent quality relatively effortlessly, but the mediocre compression quality may become an issue for transcoding...which may or may not a problem in your current situation.

    If this is just a one-time deal, the best path probably depends on the type/purpose of analysis and the compression quality of your DVD's (based on the length/bitrate), like 2Bdecided says.

    *More ways than one: Capturing straight to H.264 uses a more efficient standard than DVD's MPEG-2. Capturing to lossless lets you further improve quality with software filtering first, then allows you to have a lot more control over the H.264 encoder (e.g. x264) and encoding settings you use. Of course, quality -> effort -> premature graying.
    Last edited by Mini-Me; 21st Feb 2012 at 06:30.
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  4. Member v491138's Avatar
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    Originally Posted by yogohj View Post
    Hello

    This is my first ever post on a forum so I hope I am on the right section of the site, here it goes:

    I have about 100 vhs and s-vhs tapes which i converted to DVD a while ago. I now need to covert them to H.264 for use with an analysis program. Do I need to go back to the vhs and svhs tapes and capture them to convert to H.264, or can I go straight from the DVD to H.264. If i use the DVDs rather than the originals will it greatly affect the quality?

    any help greatly appreciated

    kind regards

    Jeannine
    These gentlemen are a trip. They know so much that unless they know as much about your project as you do, they can't be definitive in their answer. They really know their stuff. Pay attention. BUT, as has been hinted at, going back to the source will give best results. How much better is what their questions are aimed at.
    Personally, I'd go back to the original sources as a matter of course.. No question. But that is me. I do reinvent the wheel now and then as a result. So read all that these guys say and ask and you won't go wrong in the end
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  5. Member
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    v491138 has some good points. But this is actually very simple. MPEG-4 is a lossy codec. Converting a lossy codec (DVD) to another lossy codec (MPEG-4) is NOT going to result in anything better than your source. Most likely you'll end up with lower quality. At best you will get marginally lower quality after the conversion and not notice it. Go back to the source if you must convert to MPEG-4, otherwise leave the DVD copy alone.
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  6. Member 2Bdecided's Avatar
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    Originally Posted by jman98 View Post
    v491138 has some good points. But this is actually very simple. MPEG-4 is a lossy codec. Converting a lossy codec (DVD) to another lossy codec (MPEG-4) is NOT going to result in anything better than your source. Most likely you'll end up with lower quality. At best you will get marginally lower quality after the conversion and not notice it. Go back to the source if you must convert to MPEG-4, otherwise leave the DVD copy alone.
    Yes, but as the OP hasn't explained properly why they want H264, let's not presume.

    Re-capturing 100 tapes well is not a small project. If they were captured well already, it would take a lot to make re-doing it worthwhile. Some of us would rather use a decent 8Mbps MPEG-2 version as a source for H.264 encoding than go through the pain of re-capturing. Choice of encoder, bitrate, and potentially deinterlacer could all make more of a difference anyway. I'm not doubting that lossless to H.264 is better, all other things being equal. It just may not be worth it! And all other things may no longer be equal (do the VCRs and tapes still work as well as they did when the original capture was done?). Or the original capture might be terrible.

    Anyway, without more information, we don't know.

    Cheers,
    David.
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  7. Member
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    Originally Posted by 2Bdecided View Post
    Yes, but as the OP hasn't explained properly why they want H264, let's not presume.
    True, but irrelevant.

    To be even simpler...
    Your DVD -> H.264 = worse than your original DVD
    Your original VHS -> H.264 = should be better than your previous DVD conversions if you know what you are doing and the tapes haven't degraded

    It's not my problem if it makes sense to redo this or not. My experience is that many people here care nothing about how long it takes, so it's up to him to decide if it's worth it or not.
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  8. Member
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    Hi and thank you so much for your replies. I think I follow. In answer to your questions, the analysis program is a child language analysis program as I am researching this topic. To use video with the analysis program will require MP4. Originally (long ago before I had even heard of MP4) I backed up the old VHS and SVHS to DVD to give me a second copy, and yes I went through the painstaking process of capturing the whole hour on the computer and then put them on DVD (One hour/DVD and the DVD now has and audio and video folder). So,

    1. is the process of using the DVD to MPEG4 easy, or will it be fraught with problems? and will the loss of quality affect the sound and picture

    2. if i were to go through the pain staking process of vhs to MPEG4 would it be worth it.

    again any advice or further questions a great help. I have spoke to numerous technicians about this and have very varied answers. This forum is great!
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  9. 1.) DVD to H.264 in .mp4 should be easy, but the visibility of the quality loss depends on the quality of the original DVD's. You'll have to revisit 2Bdecided's advice here; how much time did you fit on each DVD? What's the average bitrate?
    2.) This is just the flip side of the above question, "How much quality will transcoding lose over going back to the original source?"
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  10. Member
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    Hello again, and thanks again for your reply. How can I find out what quality my DVDs are? At the time all I did was plug a vhs player into a mixer and then captured with a program (whose name I can not remember). Is there anyway of determining the quality from the DVD itself now?

    kind regards

    Jeannine
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  11. Bitrate Viewer, MediaInfo or GSpot can tell you the bitrate (and other properties) of the VOB file(s) on the DVD.
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  12. Member
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    Hi I downloaded mediainfo and loaded a .vob file and it says

    720x576(4:3) at 25.000fps MPEG

    does this tell me the quality?

    many many thanks

    Jeannine
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  13. What bitrate did it report? Put it in full text view: View -> Text. Copy and paste the entire report here. But that will only be a hint to what the quality of your video is. I recommend you convert one of your VOB files to h.264 MP4, then re-capture one of the tapes with a lossless codec, then convert that to h.264 MP4. Compare the two and decide for yourself if re-capturing is worth the extra effort.
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  14. Member
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    yes thats a good idea. I will try it, any ideas or advice about what program will be the best for converting MPEG2 to H.264, someone mentioned to me that the sound would no longer match the picture if i did this and that mpeg2 splits it into load of files and they have to be combined. Is there a program that overcomes this type of problem?

    many many many thanks
    j
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  15. Originally Posted by yogohj View Post
    yes thats a good idea. I will try it, any ideas or advice about what program will be the best for converting MPEG2 to H.264, someone mentioned to me that the sound would no longer match the picture if i did this
    That's probably not going to be a problem. Try Xvid4PSP, ripbot64, Handbrake, etc.
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  16. Member themaster1's Avatar
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    for me:
    - staxrip for interlaced video)
    - mediacoder for progressive video (and cuda encoding support)
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  17. Member 2Bdecided's Avatar
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    Originally Posted by jman98 View Post
    True, but irrelevant.
    Apparently not...
    Originally Posted by yogohj View Post
    Hi and thank you so much for your replies. I think I follow. In answer to your questions, the analysis program is a child language analysis program as I am researching this topic.
    This doesn't sound like the ultimate quality when viewed on a 40" plasma is relevant at all.

    Jeannine, can you provide a link to this program? It's surprising if there's no way of getting MPEG-2 video into it (maybe by installing a relevant codec).
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  18. Member 2Bdecided's Avatar
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    Originally Posted by yogohj View Post
    yes thats a good idea. I will try it, any ideas or advice about what program will be the best for converting MPEG2 to H.264, someone mentioned to me that the sound would no longer match the picture if i did this and that mpeg2 splits it into load of files and they have to be combined.
    It'll only unsynchronise the sound if you do it wrong. MPEG-2 isn't split into loads of file - it'll be split into about 5 files on the DVD-R, but any decent software will take care of that, and give you a single file, or files split into chapters (if the DVD had chapters, and you ask the converter to keep them).

    There are loads of 1-click DVD>mp4 converters out there - paid and free. themaster1 has made good suggestions (if these videos are straight from a normal video camera, they will be interlaced - you might need to convert them to progressive, depending on what this analysis software does with them) - but I'd double-check that MPEG-2 isn't acceptable first.

    Cheers,
    David.
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  19. Member
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    Hi

    Thanks again for all your help. It is so kind of you all to help me with this problem. the forum really is great.

    My lack of knowledge about video is really starting to show and I do feel a bit out of my depth

    I tried to download several of the programs that were suggested. My computer could not open the extraction file for one of them, then did not have something else for another, and one (as it is my work computer) i was not the adminstrator and could not do it.

    Anyway, I have finally downloaded mediacoder, which looks fairly straightforward but I started it and I am lost. I tried to do the wizard but I did not understand most of the questions. I then tried opening my file and then it said that the output file is not right, but i do not know how to change it. I also can not see how to specify that i want mpeg2 to mpeg4, sorry for being a video-techie dunce.....any offers of help greatefully appreciated!

    jeannine
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  20. Member
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    oh and you are right, the video is not to display on a 40" widescreen, it will just be a small window on a computer screen (does this mean that the quality does not matter as much?)
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