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  1. I am about to do som basic editing like cutting, adding titles and basic transitions and probably perform some color and white balance corrections.
    If I open an AVCHD file to do these actions and re-render in the same format, would that generate a loss in video quality?
    If I re-render the samt file in MPEG2 or MPEG4, would that decrease the video quality compared to the original AVCHD file?
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  2. Dinosaur Supervisor KarMa's Avatar
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    What program(s) are we talking about.

    If I open an AVCHD file to do these actions and re-render in the same format, would that generate a loss in video quality?
    Anytime you encode a video with a lossy encoder, you will lose quality. Depending on the settings and codec used, this can be minimized but it will never be exactly the same. Using more efficient standards like H.264 with a high enough bitrate, should make for transparent results. The best codec for the H.264 standard would be x264. x264 also supports CRF, with takes the guess work out of picking the right bitrate.

    There are smart editors out there like Videoredo, which will only re-encode only the cut the points while just copying rest (~99%) of the video file. But to do color editing, that would need a re-encode.

    If I re-render the samt file in MPEG2 or MPEG4, would that decrease the video quality compared to the original AVCHD file?
    MPEG2 is pretty old and should be generally avoided unless necessary. Not exactly sure what MPEG4 is referring to (part 2 or part 10) but that does not inspire confidence.
    Last edited by KarMa; 20th Mar 2016 at 05:07.
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    Originally Posted by KarMa View Post
    The best codec for the H.264 standard would be x264. x264 also supports CRF, with takes the guess work out of picking the right bitrate.
    I think you have it backwards. "h.264" is the codec, "x264" is an encoding engine, not the other way around.

    Originally Posted by KarMa View Post
    MPEG2 is pretty old and should be generally avoided unless necessary.
    Bull. MPEG2 is still the defacto broadcast standard.
    - My sister Ann's brother
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  4. Ok. Would you say I should aim at using the h.264 codec as the "base codec" for my capture if possible"?
    Is the h.264 one of the many codecs used in the AVI container but a bit more compressed compared to the Lagarith for instance?
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  5. Dinosaur Supervisor KarMa's Avatar
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    Originally Posted by LMotlow View Post
    Originally Posted by KarMa View Post
    The best codec for the H.264 standard would be x264. x264 also supports CRF, with takes the guess work out of picking the right bitrate.
    I think you have it backwards. "h.264" is the codec, "x264" is an encoding engine, not the other way around.
    H.264 is the standard, x264 conforms to the H.264/AVC/MPEG4 Part10 standard. Same way x265 conforms to the new HEVC/MPEG-H Part 2 standard. Same way HCenc conforms to the MPEG2 video standard (aka MPEG-2 Part 2).

    See https://en.wikipedia.org/wiki/Video_codec - Often codec and encoder are used one in the same, even though many encoders don't come with a decoder.

    Originally Posted by LMotlow View Post
    Originally Posted by KarMa View Post
    MPEG2 is pretty old and should be generally avoided unless necessary.
    Bull. MPEG2 is still the defacto broadcast standard.
    To who?
    The United States with ATSC? Yes, simply because it takes forever to move on from outdated standards. MPEG2 is the standard that just won't die already, simply for economic reasons. It's cheaper to do nothing and stay with inefficient video compression, than to replace everyone's TV with a new ATSC tuner. We are still some time off from a complete switchover to ATSC 3.0, considering I don't even think 4K TVs of today have them. Also a H.264 license is more expensive than for MPEG2.

    Satellite companies in the US are also very slow to move away from MPEG2 for the same reason. Despite making a fortune on decoder box rentals, many companies don't feel the need to pay to replace to H.264 boxes. So people are stuck with low bitrate MPEG2 satellite channels. I saw a HEVC box last year so maybe they will move on that.

    In the UK, all Freeview channels (OTA) use H.264 which improves their efficiency greatly. While here in the US, I still see blocks on my OTA 1080i channels even at 15Mbit. Often when these HD MPEG2 channels share bandwidth with multiple channels, the main HD channel is forced to share bandwidth driving quality down drastically. Deinterlacing also becomes ugly with such broadcasts.

    I even have Bluray's encoded to the MPEG2 standard, one encoded at ~27Mbit with blocking artifacts because of film noise. Move on already.
    Last edited by KarMa; 20th Mar 2016 at 07:00.
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  6. Dinosaur Supervisor KarMa's Avatar
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    Originally Posted by fuga View Post
    Ok. Would you say I should aim at using the h.264 codec as the "base codec" for my capture if possible"?
    Is the h.264 one of the many codecs used in the AVI container but a bit more compressed compared to the Lagarith for instance?
    The AVCHD container contains video that conforms to the H.264 video standard, even the name AVC is just another name for H.264. Advanced Video Coding. So your AVCHD source is already H.264, along with AC3 audio in the container.

    Which ever H.264 encoder you have access to would probably be the best option when rendering, besides something lossless like Lagarith. If you have access to x264, that would be best.
    Last edited by KarMa; 20th Mar 2016 at 07:13.
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  7. Member budwzr's Avatar
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    What's nice about Mpeg2 is it's easy on system resources. Also, many NLE's support Smart Render of Mpeg2.
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