DV codec & Encoding

[kenackr]

I'm re-reading my video books to get some things to stick in my brain better.

In going through : "Editing Digital Video" by Robert Goodman & Patrick McGrath, there's explanation of "What's the DV codec" on page 234. The following sentences appear:

"If your editing system is connected to a DV camcorder or recorder through an IEEE-1394 cable, the codec is unimportant. No compression or decompression happens. You're just doing a data transfer, nothing goes through the codec."

2 sentences later, " The codec is involved whenever transitions, titles, or effects have to be rendered."

Question 1: Are these statements about the DV codec factual?
1a: Applicable only to your NLE?

On page 235 under "What's an encoder?", the following statements are made:

"Encoding is the process of converting from one format to another. Encoding happens in your camcorder when the pictures and sounds are recorded in the DV format. The camcorder has a hardware encoder that converts the information captured by the CCD's and microphone in to the compressed (5:1) DV format that is recorded to tape."

Question 2: Is the 5:1 compression used to convert to the DV format LOSSY or loseless?

Question 3: Specifically, can the compression be removed once in the NLE or by a capture card to provide uncompressed data?

Question 4: If so, can you please state which capture card or NLE?

:embarasse


Ken

 

[maniero]

1.) Everytime you capture DV footage with any NLE it will appear as DV AVI file which is the best possible quality for DV footage.
2.) Well, 5:1 compression is of course lossy (with a rate of 5:1...), but this compression happens inside the camcorder and is not removable, if you don't have an andromedized DVX...
3.) no

If I'm wrong, please corect me...

 

[kenackr]

Thank for the reply.

The reason I asked about lossy vs. lossless is that I'm aware of the ability of some software which gets compressed to be re-xpanded upon receipt, like zip files for example.

Data compression and decompression is alive and well in many digital domains. I just didn't know if the encoding process to DV format was capable of that.

Thanks for clearing that up.

Ken