ERIC suggestion re video encoding problems

[asetoftools]

19gb for a 15 minute video is insane. I do not know if you are using adobe premiere, but frame size does not matter so much. What is more important is the export codec (should be mp4 h264), and also the bitrate. A target bitrate of 2mbps is probably more than sufficent for youtube. and the filesize will be under 1gb and take a few hours to encode on a core i5 or core2 quad.

none of this multiple day encoding you are dealing with!!!

Screen shot attached is from adobe premiere cs6, however other video editors should also let you set the bitrate. I think bitrate and codec is going to be what simplifies your life. Frame size doesnt really matter too much and you should even be able to get away with 1920×1080 if you use the above settings and get a reasonable filesize out of it.

sorry if you know all this and i am preaching to the choir. In my day job, i have to encode edit and transcode the occasional video. So i am not a super expert on it, but know enough about file size vs quality and where to make the appropriate compromises.

another thing to make sure if you are going to do mp4 codec (h264) is that you have a codec pack installed on your machine, so you can view the file afterwards. I recommend K-lite codec pack available here:
http://codecguide.com/

The problem you are having where you reduce the frame size and the file gets bigger could be because more interpolation has to be done as its the wrong aspect ratio or something now. you should always use the frame size of the incoming RAW video, which in your case is all probably the same. Make that match in your project and you will avoid any incorrect aspect ratio or other weird artifacts.

hope this helps!! i notice you complain about file sizes alot, and i dont think you are trying to post like 10 hours worth of video, which is what 19gb would be. 10-20 hours of 1080p video would probably equal 19gb compressed with mp4. I have never seen that long a video from you so i am guessing your bitrate is probably set far too high, or you are exporting to MPEG2 or something.

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[EricTheCarGuy]

I’ve actually taught classes in compression and believe I have a pretty good understanding of it. BTW, it’s a 5.5 hour video, not 15min. I’m also using FCP with compressor to handle the encoding. Yes, frame size does matter. The smaller the frame, the less info you have to compress and smaller file sizes will result. I don’t want to get the frame size too small or it won’t look as good. As you know with compression you need to balance quality with file size and that’s a tightrope walk for sure. I’ve done testing on smaller portions of the video to ensure quality but the full video takes 4-5 days to make. I don’t know what size it turns out to be until after it’s done.

Thanks for your input. I very much appreciate it.

[César Morgan]

A little tip:
Another property on video encoding is the keyframe interval. a Keyframe is a complete image inside the video data, all other frames are just color variations from the last keyframe. A keyframe appears (normally) a few seconds after the last one. You could try to increase the keyframe interval (if there’s any option to do that, otherwise you’ll have to re-process an exported moviewith 3rd-party software) so these keyframes will be less common. The normal (color variation) frames are smaller packets than keyframes.

[Author]

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