3 ms·

Nice one. The key is the `-c copy -map 0` option which preserves the same codecs and stream metadata. This makes the edit operations nearly instant too. While

Nice one. The key is the `-c copy -map 0` option which preserves the same codecs and stream metadata. This makes the edit operations nearly instant too. While on the topic of ffmpeg uses, here is a script I posted that speedup videos by a factor of 1.5: https://news.ycombinator.com/item?id=22584131 https://news.ycombinator.com/item?id=22584131 (use case record an unscripted screencast or demo with lots of pauses and uhms, then speed it up to make it look like you are super well prepared and caffeinated --- hidden bonus: if demoing a software product it will appear to be 33% faster!)

verst 7y ago
Thanks! I'll check out your speed up trick. I also discovered the ffmpeg reddit today. I've been playing around a bunch with FFmpeg these last few days because I thought it was ridiculous I had to manually perform certain tasks in ScreenFlow which appeared entirely programmable. I have another more interesting post on subtitles / captions, but that is for a more niche audience. Pretty interesting how H.265/HEVC Hardware encoding differs across platforms and how software encoding produces much smaller files at the same quality.
- userbinator 7y ago
  Pretty interesting how H.265/HEVC Hardware encoding differs across platforms and how software encoding produces much smaller files at the same quality. Consumer hardware encoders are more constrained than software in what they can do, and thus are usually designed to optimise what they are best at: encoding speed and power efficiency.
- cm2187 7y ago
  Am I the only one to have stability problems when playing h265 with VLC on Windows?
  - brokenmachine 7y ago
    I have no problems. I'd check your GPU drivers.
joshstrange 7y ago
I haven't tried speeding up TV before, I think that would ruin some of what I like about TV (and I use Plex which doesn't have that option) but podcasts I speed up with Overcast and I've been watching a little more on Youtube (news, tutorials, etc) lately and I've really used the playback speed options a lot. Normally 1.5 is fine as long as I'm paying attention. Sometimes if I'm trying to get something down word-for-word I'll slow it down to .5 so I can keep up (I guess I'm not a very fast typer). I love being able to control it so easily.
aasasd 7y ago
VLC can speed video or audio up/down on the fly, preserving audio pitch. I'm using it with audiobooks and old movies, and also occasionally (without pitch lock) to turn hard house into sweet groovy house or breakcore into playful idm, as suggested by RDJ himself—see https://youtube.com/watch?v=5yBvP3616Wc https://youtube.com/watch?v=5yBvP3616Wc and https://youtube.com/watch?v=aWqf17mUyoQ https://youtube.com/watch?v=aWqf17mUyoQ Btw, for some reason ffmpeg doesn't do well with changing speed of music—the result sounds poor compared to VLC. I found that `sox` gives better quality.
- RMPR 7y ago
  Mpv too
  - lozf 7y ago
    Plus `mpv` has awesome keyboard controls in case you need to skip back and return to normal speed, or loop a segment etc.
    - capableweb 7y ago
      Lots of love to mpv in general because it's an awesome tool, but VLC also have hotkeys for those things + I'm pretty sure VLCs feature set is much larger than mpv while still being super lightweight. Found this page but don't think that's all the hotkeys available even: https://wiki.videolan.org/QtHotkeys/ https://wiki.videolan.org/QtHotkeys/
      - RMPR 7y ago
        Same here but for what it does support, mpv is the beast.
- aasasd 7y ago
  Ah, and I neglected to note that VLC does the speed-trick both on desktop and Android. On a phone, it's not quite perfect for audiobooks due to some hiccups in controls, but the versatility is its favor.
6510 7y ago
I dont know what it is called but they use to start radio shows some seconds (or minutes?) before broadcasting them. Some technology was used to skip tiny parts where the host was silent (breathing or going uhhhmmm)
- dspig 7y ago
  Profanity Delay, e.g. https://www.eventideaudio.com/products/rackmount/profanity-delay-dump-button/bd600e https://www.eventideaudio.com/products/rackmount/profanity-d...

verst 7y ago

Thanks! I'll check out your speed up trick. I also discovered the ffmpeg reddit today. I've been playing around a bunch with FFmpeg these last few days because I thought it was ridiculous I had to manually perform certain tasks in ScreenFlow which appeared entirely programmable. I have another more interesting post on subtitles / captions, but that is for a more niche audience. Pretty interesting how H.265/HEVC Hardware encoding differs across platforms and how software encoding produces much smaller files at the same quality.

userbinator 7y ago
Pretty interesting how H.265/HEVC Hardware encoding differs across platforms and how software encoding produces much smaller files at the same quality. Consumer hardware encoders are more constrained than software in what they can do, and thus are usually designed to optimise what they are best at: encoding speed and power efficiency.
cm2187 7y ago
Am I the only one to have stability problems when playing h265 with VLC on Windows?
- brokenmachine 7y ago
  I have no problems. I'd check your GPU drivers.

joshstrange 7y ago

I haven't tried speeding up TV before, I think that would ruin some of what I like about TV (and I use Plex which doesn't have that option) but podcasts I speed up with Overcast and I've been watching a little more on Youtube (news, tutorials, etc) lately and I've really used the playback speed options a lot. Normally 1.5 is fine as long as I'm paying attention. Sometimes if I'm trying to get something down word-for-word I'll slow it down to .5 so I can keep up (I guess I'm not a very fast typer). I love being able to control it so easily.

aasasd 7y ago

VLC can speed video or audio up/down on the fly, preserving audio pitch. I'm using it with audiobooks and old movies, and also occasionally (without pitch lock) to turn hard house into sweet groovy house or breakcore into playful idm, as suggested by RDJ himself—see https://youtube.com/watch?v=5yBvP3616Wc https://youtube.com/watch?v=5yBvP3616Wc and https://youtube.com/watch?v=aWqf17mUyoQ https://youtube.com/watch?v=aWqf17mUyoQ Btw, for some reason ffmpeg doesn't do well with changing speed of music—the result sounds poor compared to VLC. I found that `sox` gives better quality.

RMPR 7y ago
Mpv too
- lozf 7y ago
  Plus `mpv` has awesome keyboard controls in case you need to skip back and return to normal speed, or loop a segment etc.
  - capableweb 7y ago
    Lots of love to mpv in general because it's an awesome tool, but VLC also have hotkeys for those things + I'm pretty sure VLCs feature set is much larger than mpv while still being super lightweight. Found this page but don't think that's all the hotkeys available even: https://wiki.videolan.org/QtHotkeys/ https://wiki.videolan.org/QtHotkeys/
    - RMPR 7y ago
      Same here but for what it does support, mpv is the beast.
aasasd 7y ago
Ah, and I neglected to note that VLC does the speed-trick both on desktop and Android. On a phone, it's not quite perfect for audiobooks due to some hiccups in controls, but the versatility is its favor.

6510 7y ago

I dont know what it is called but they use to start radio shows some seconds (or minutes?) before broadcasting them. Some technology was used to skip tiny parts where the host was silent (breathing or going uhhhmmm)

dspig 7y ago
Profanity Delay, e.g. https://www.eventideaudio.com/products/rackmount/profanity-delay-dump-button/bd600e https://www.eventideaudio.com/products/rackmount/profanity-d...