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On 22/12/2021 19:27, Daniel Pielmeier wrote: |
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> Wol schrieb am 22.12.21 um 19:45: |
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>> What is an i-frame? As I understood it, typically when you had a scene |
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>> change, a frame was written in full, then subsequent frames were |
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>> stored as diffs. Is that what an i-frame is? |
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> |
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> Wikipedia [1] to the help. |
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> |
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>> In which case, surely it can't be that tricky to delete a block |
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>> without having to decode/encode more than a few frames? |
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> |
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> Encoding only the affected region is tricky because you need to use the |
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> same codec parameters (encoding profile, resolution, colour space, FPS, |
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> bit depth, bitrate, and possibly more parameters which are also codec |
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> dependent) like the rest of the unaffected portion of the video to be |
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> able to concatenate it again afterwards with the rest of the video. Also |
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> it is tricky to keep video an audio in sync when having a lot of cut |
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> points. Probably there are other issues depending on the required |
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> codecs. So making it work for every codec even only for the popular ones |
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> might be a lot of work. |
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> |
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> TTCut can do "smart cutting" by encoding only the affected GOP [2]. |
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> However it only works for Mpeg2 Video and Mpeg2 Audio or Dolby AC-3 |
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> Audio. I have not tested it but VidCutter [3] should also be capable of |
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> doing so and as I see there is no restriction on the codecs. They are |
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> the only ones I am aware of supporting this feature and they are |
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> packaged for Gentoo. |
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> |
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> [1] https://en.wikipedia.org/wiki/Video_compression_picture_types |
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> [2] https://en.wikipedia.org/wiki/Group_of_pictures |
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> [3] https://github.com/ozmartian/vidcutter |
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> |
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Cue another bout of screaming. |
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TTCut doesn't recognise .ts, and when force-fed just crashes. |
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Vidcutter won't emerge - its dependency mpv bombs with |
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Checking for wayland-scanner |
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: no |
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You manually enabled the feature 'wayland-scanner', but the |
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autodetection check failed. |
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* ERROR: media-video/mpv-0.33.1-r2::gentoo failed (configure phase): |
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* configure failed |
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Now where would I have enabled wayland-scanner? |
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Cheers, |
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Wol |
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