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  1. Member
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    Back in the analog days we used to get smoother 2x or 3x (or whatever) fast forward and rewinding. You could watch the video as it moved.

    Since the era of DVD, everything is jumpy. We're skipping forward or backward.
    And that's in the best case scenario. Sometimes all we get is a timeline bar and can move the play position marker forward or backward. It won't even give you the skipping forward and backward.

    There is no real rewind or fast forward anymore.

    Why is this?
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  2. DECEASED
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    Depending on the software /hardware that you use, you still have the options fast-playback and slow-playback.

    Originally Posted by roxics View Post
    Why is this?
    Because magnetic tape didn't allow random access to the recorded data, but hard disks, optical discs and solid-state media do.
    So, in the old days FF and RW was the best we could have, but not what "everybody" or most-people really wanted...
    "Programmers are human-shaped machines that transform alcohol into bugs."
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  3. Member
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    I don't remember most people being polled on the issue. If you can recommend a set-top Blu-ray player that does proper FF and Rew I'd love to know. It seems more like companies just cheaped out on the feature.
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  4. Modern video is compressed. There is a limit to how fast it can be decompressed. Different devices have different limits but you're often limited to something like 2x or 4x. Once you go beyond the limit the device has to skip frames -- leading to jumpy playback. Also, devices like DVD and Blu-ray players have a limit to how fast the discs can spin (and hence, how fast data can be read off the discs), making it even more difficult and jumpy.
    Last edited by jagabo; 18th Jul 2021 at 13:57.
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  5. Member Cornucopia's Avatar
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    For smooth playback of solidstate media with modern processing, it shouldn't be too big of an issue, but is highly dependent on read-ahead buffer size. Most apps do not read ahead more than probably 3 or 4 frames worth (enough to fully decode a complex B-frame). Changing the read style to be something like FFWD, it would likely need to read only Intra-frames, which then means limiting to certain speed ratio increments. Within limits, as was mentioned.
    Greater flexibility requires much larger buffer sizes, for very niche requirements (as that isn't what most really are looking for), so it would only be a very specialty app that would be coded this way.


    Scott
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    Originally Posted by jagabo View Post
    Modern video is compressed. There is a limit to how fast it can be decompressed. Different devices have different limits but you're often limited to something like 2x or 4x. Once you go beyond the limit the device has to skip frames -- leading to jumpy playback. Also, devices like DVD and Blu-ray players have a limit to how fast the discs can spin (and hence, how fast data can be read off the discs), making it even more difficult and jumpy.
    That makes a lot of sense. Thank you. Just unfortunate we've lost this ability while gaining the other advantages of digital.
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    Originally Posted by Cornucopia View Post
    For smooth playback of solidstate media with modern processing, it shouldn't be too big of an issue, but is highly dependent on read-ahead buffer size. Most apps do not read ahead more than probably 3 or 4 frames worth (enough to fully decode a complex B-frame). Changing the read style to be something like FFWD, it would likely need to read only Intra-frames, which then means limiting to certain speed ratio increments. Within limits, as was mentioned.
    Greater flexibility requires much larger buffer sizes, for very niche requirements (as that isn't what most really are looking for), so it would only be a very specialty app that would be coded this way.


    Scott
    Yeah I can do this in my NLE software using the JKL keys. But I was just curious why this wasn't common on set-top DVD/Blu-ray players and most streaming services and file based software like Plex. Would certainly make it easier to get to exactly where you want to get to.
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  8. Member Cornucopia's Avatar
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    Settops are commodity items which try to keep their profit by using minimal resources. This includes buffer size.


    Scott
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