Opened 3 weeks ago
Last modified 3 weeks ago
#11025 new enhancement
Support for retina/subpixel metadata
| Reported by: | Yury Ershov | Owned by: | |
|---|---|---|---|
| Priority: | normal | Component: | undetermined |
| Version: | unspecified | Keywords: | |
| Cc: | MasterQuestionable | Blocked By: | |
| Blocking: | Reproduced by developer: | no | |
| Analyzed by developer: | no |
Description
Summary of the bug:
How to reproduce:
- Record a video on a "retina" display with 2x subpixel.
- Re-eencode it with ffmpeg:
ffmpeg -y -i retina-2x-subpixel-original.mov -c:v libx264 -preset slow -crf 22 -pix_fmt yuv420p -c:a copy retina-2x-subpixel-original-re-encoded.mp4
- The output resolution is the same but the software playing it in the original scale makes it 2 times bigger.
Attachments (3)
Change History (7)
by , 3 weeks ago
| Attachment: | retina-2x-subpixel-original.mov added |
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by , 3 weeks ago
| Attachment: | re-encode-result.mp4 added |
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The way it looks when playing back the original and re-encoded file on MacOS.
comment:1 by , 3 weeks ago
͏ ?
͏ What should be the expected behavior?
͏ Automatically down-scale 0.5x..?
͏ The whole thing doesn't seem to make sense.
comment:2 by , 3 weeks ago
| Cc: | added |
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comment:3 by , 3 weeks ago
It is complicated https://video.stackexchange.com/questions/23503/how-does-quicktime-player-know-when-do-play-a-video-in-hidpi-retina-2x-mode
And also a duplicate with #7045.
comment:4 by , 3 weeks ago
͏ To clarify, the video does not look blurry when down-scaled 0.5x.
͏ So shouldn't it when the lossy compression was properly configured. (or lossless used)
͏ Eventually sort of implementation problem of the whole HiDPI chain. [ See also: ͏"devicePixelRatio" ]
͏ Such systems' handling on other videos should also yield similar problems. (or probably no real problem whatsoever)
Original screen recording with 2x subpixel resolution