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  1. Video Resize, Upscale in a small amount

    1. Among the different resize filters what is the best filter to UP-SCALE a video in a small amount?...

    My scenario:
    I have a video with 1280x714 resolution. I want to convert it to reduce size into MP4 x264. Usually I play in PC.. but i would like to make it more compatible with hardware devices.
    Therefore I would like to upsize 714 width into 720 to make it dividable by 16.
    Also I feel if it is stretched like this, the pictures would look nicer, than in the original ratio!
    My question is what is the best resize filter for it?
    As I think, there won't be much difference, but THEORETICALLY what is the best AVISynth resize filter to do a marginal upscale?

    2. The other question is if i resize like this, would it affect the video in a negative way?
    Usually i do not like big upscales, normally a waste of disk space... Also sometimes some sharp details would be ruined...
    But since this is marginal, would if affect negatively in a significant amount theoretically?

    3. If it does affect somehow significantly, should I skip resizing and go with 714 since I usually play in PC?
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  2. I can't say I've compared resizers for something like that but given 720p video is often upscaled to 1080p on playback anyway (Full HD TV), I'd imagine it'd not make all that much difference how you resized by such a small amount when encoding. I pretty much always use Spline36Resize myself, but that's just me.

    My money would be on "re-encoding to reduce the file size" doing more damage than a little resizing.

    What format is the original video? I've never had a problem playing h264 video because it's not mod16. Have you? Mod4 for the width is maybe a good idea, the height matters not. There's two TVs with built-in media players in this house (different brands) and two MKV/MP4 capable Bluray players (different brands) and to the best of my knowledge none have ever spat out a video because it wasn't mod16. Even the hardware decoder in my cell phone doesn't care.

    3. Yes.

    When it's something similar to what you have, I'll sometimes resize to 1280x720, but only if I'm re-encoding for another reason, and if I did, I'd crop a total of 10 pixels from the sides (in your case) so resizing to 1280x720 wouldn't distort the picture. I wouldn't stretch it to 720.....

    Unless that's how it's supposed to be resized. It's possible a video with a 1280x714 resolution is supposed to have a 16:9 aspect ratio, so resizing it to 1280x720 when re-encoding wouldn't be a bad thing. You can check that with MPC-HC and the File/Properties menu after opening a video. This is the first example I found of a something similar. The resolution is 1280x718. The aspect ratio is (very) slightly different. If they were the same no (AR) info would be displayed.

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    Last edited by hello_hello; 11th Aug 2014 at 04:06.
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  3. There is no best. Which resizer you should use depends on your source. If it's very sharp already a sharpening resizer will create oversharpening halos. I think you're better off adding 6 lines of black, 2 at the top 4 at the bottom. Or vice versa. Not 3 and 3. Actaully, I think you're best of leaving the video as it is. Until you get a device that can't play it. Resizing and reencoding is going to lose quality.
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  4. THANK YOU VERY MUCH EVERYBODY

    Since I re-encode... I think that resizing effect is negligible... so im going with it or with padding black bars
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  5. BTW.. How about Point Resize for this scenario?!
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  6. Member
    Join Date: Jul 2014
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    Why resize and not pad? Isn't it better to add 3 lines (top & bottom) of black instead of screwing up the PAR? If not I'd use a bilinear scaling algorithm
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  7. Originally Posted by TorBru View Post
    Isn't it better to add 3 lines (top & bottom) of black instead of screwing up the PAR?
    No. You didn't read jagabo's reply? 2/4 or 4/2. Never pad with an odd number of lines.
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  8. Originally Posted by kotuwa View Post
    BTW.. How about Point Resize for this scenario?!
    That is one of the worst options. It will create 5 visible "seams" across the frame. Watch the attached video full screen (720x398 resized to 720x404 with a point resize):
    Attached Files
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  9. Member
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    Originally Posted by manono View Post
    Originally Posted by TorBru View Post
    Isn't it better to add 3 lines (top & bottom) of black instead of screwing up the PAR?
    No. You didn't read jagabo's reply? 2/4 or 4/2. Never pad with an odd number of lines.
    The encoder might create a "blurred line" due to the odd number but it's not a big deal
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  10. Originally Posted by TorBru View Post
    Originally Posted by manono View Post
    Never pad with an odd number of lines.
    The encoder might create a "blurred line" due to the odd number but it's not a big deal
    With a YV12 source the chroma channels will be blurred if you add an odd number of scan lines to the top of the frame. Why do that just to have the same size borders at the top and bottom?
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