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Re: Is a capture and playback device a passthrough or a pitstop?

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Gary Hazen
Re: Is a capture and playback device a passthrough or a pitstop?
on Jan 4, 2012 at 1:49:59 pm

I think I removed too much of the original quote. Here's the entire quote from the first post.

[Frank Black] "we call it uncompressed because the playback just orders the lost data to come out where it has fled to and get back in line to form a full original file in all its megabytes, and the guys that aren't coming back -- well we won't even notice they're gone. and so and so. "

You say "uncompressed" at the beginning of the quote and then describe compressed video at the end. In simple terms, the playback of compressed video doesn't make it uncompressed. All I'm saying is that the "we" you reference in your post is mucking up the language.

I can feed an SDI signal into my Avid and set the amount compression (ex: 1:1, 2:1, 10:1, etc.)
If I record some video at 10:1 and play it back I'm viewing video that was compressed at a ratio of 10:1. To say that I'm viewing "uncompressed video" would be incorrect.

[Frank Black] "why do we say that a cap and play device transfers uncompressed when a camera compresses the data when recording it, and since the camera's decompression doesn't fully restore."

With no reference to the actual hardware or the settings this statement is meaningless.

If you plug a Sony 1550 into a Sony HDCAM SR the recording and playback will be uncompressed.
If you record on a Sony PD150 (DVCAM) the signal will be compressed.

If you had both cameras on the set and checked playback you wouldn't say that the signal coming off the PD150 was uncompressed. Well, the "we" you reference might say that, but it would be an incorrect statement.

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