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Issues with video corruption


JLamb
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A6000 body, 18-200mm OSS. 

On most of the videos I film the first 3 seconds end up choppy when I replay them on my computer and for those who I share the videos with.  When I push play it will show the video is playing but the frame is frozen for a sec and then it jumps to a fast motion to catch up for another second  then ends up playing the rest of the video correctly. it plays just fine on my camera from what I can tell.

Is this an issue with my camera or the memory card perhaps? Anybody have this happen before? seems like the files get corrupted somewhere along the way. Also, doesn’t seem to matter what program I use to import. 

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To me this sounds like the computer you're using for playback needs a noticeable amount of time to load both the playback software plus a sufficiently large portion of the video file into memory.

In a way, the computer maintains a buffer (pretty much like a bucket of water), which gets both filled and drained at the same time. The fill rate needs to be higher than the drain rate, so the desired drain rate can be sustained and the bucket does not run empty. At the start of the playback, you start draining already, while things still need to be loaded into memory, which is sort of a "distraction" from the necessary fill rate.

The playback of any video should be less choppy (or not choppy at all) when you rewind and re-play it for a second time. It should be all in memory by then.

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On 2/10/2020 at 3:05 AM, Chrissie said:

To me this sounds like the computer you're using for playback needs a noticeable amount of time to load both the playback software plus a sufficiently large portion of the video file into memory.

In a way, the computer maintains a buffer (pretty much like a bucket of water), which gets both filled and drained at the same time. The fill rate needs to be higher than the drain rate, so the desired drain rate can be sustained and the bucket does not run empty. At the start of the playback, you start draining already, while things still need to be loaded into memory, which is sort of a "distraction" from the necessary fill rate.

The playback of any video should be less choppy (or not choppy at all) when you rewind and re-play it for a second time. It should be all in memory by then.

Chrissie, thanks for the reply.  No matter how many times I rewind a video it does the same thing.  This also happens on any computer I load the video onto as well.  Any other thoughts?

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