What is the best lossless compression for video?

If captured in NTSC DV, it is uncompressed.

It was compressed 5:1 in the camera with a 4:1:1 chroma sampling.

Export your finished sequence back to tape.

DV source material does shrink some if you ZIP it (ctrl-click on it in the Finder and select Make Archive). Certainly lossless...

Patrick

Are the files currently uncompressed, or are they DV? If quality is priority number one, then I would leave it as DV. You can always use the DV version to make DVDs or movies for the web and not need to re-render an H.264 or whatnot.

Just to reiterate what others are saying:

If your footage is DV, and you captured as DV/NTSC or DV/PAL, then your footage already is as uncompressed as it is going to get. Just back up those files to another drive.

If you convert it to any other format then you are adding compression. If you compress it to fit on a VIEWABLE DVD, then you will be adding a LOT of compression. If you copy them to DVDs as data files, it will take a LOT of DVDs.

Shane

For DVD : Use Compressor to export using MPEG-2

Also try exporting back to tape. Exporting back to tape will guarntee that your quality will not be lost.

BP

For DVD : Use Compressor to export using MPEG-2

This is not good for backing up material for later use.

Shane

NTSC DV is compressed.

If you use h.264, you compress it again.

There is no such thing as lossless compression.

That is a oxymoron.

There are lossless codecs, but if you compress video, it losses quality.

You can convert NTSC DV to 10-bit uncompressed, but all you are doing is creating a larger file of the original compressed footage.

There is no such thing as lossless compression.

This is not really true. There are many ways to compress - just google "compression algorithms" and you'll find some. Two basic schemes are either lossless or lossy. Lossless seeks to remove redundant or repetitive information, this is like Run Length Encoding or LZW encoding. Lossy throws away information that is generally "not perceived". JPEG, MPEG, H.264, DV are examples of lossy compression.

YUV "lossless" is 4:2:2 and is considered uncompressed, yet it takes up less space than RGB 4:4:4 encoding. Simply zipping the file compresses it (uncompressed codecs squeeze better, but DV does compress, indicating redundant information) - a TIFF sequence might have run length encoding or LZW. Both are lossless.

To get back to the question, Patrick:

Losslessness is more important than size.

H.264 is a fantastic compression - it is, however, FAR from lossless AND it is not directly editable. You'd need to convert it back to an editable format, ensuring even more loss. Not within the parameters of your desired solution...

Patrick

Patrick:

We are talking a little semantics.

Compressing throws away information any way you look at it. Whether it is repetitive, or redundant, it still is information.

That's the point I was trying to make.

Take care

Ah, I see. The point I was trying to make is that Lossy Compression throws information away that does not come back upon expansion. Lossless Compression "shrinks" the information, but upon expansion, nothing is lost from the original...

Patrick

It occurs to me that some explanation might be in order. Compression can take many forms. Most of our software updates are compressed for delivery, yet expand with no loss. Sound and imagery can also be losslessly encoded. If, instead of storing 720x480 of zeros to represent a black screen, I just store a notation that says 720x480 zeros, I store the same information, but in a smaller space, no? Nothing is lost.

Here's an analogy - it's like trying to fit a pile of clothes into a drawer.

Folding clothes instead of jumbling them in will let you get more clothes in the same space. Nothing is lost. No difference in the clothes. That is lossless compression.

Lossy compression would look at the pile of clothes and say "You never wear this shirt anyway - you won't miss it" and it throws it away. You can see how Lossy compression can be more efficient.

Patrick

Lossy compression would look at the pile of clothes and say "You never wear this shirt anyway - you won't miss it" and it throws it away. You can see how Lossy compression can be more efficient.

Okay Patrick, how about this one.

How does compression such as NTSC DV (5:1) interrelate to chroma sampling such as 4:1:1 for NTSC or 4:2:0 for HDV or 4:2:2 for DVCProHD100?

In two sentences or less, please -- using the clothes hamper analogy.

It's the same thing - lossy compression. It takes advantage of the fact that we are more sensitive to luminance information than chrominance, so throws away some color information ("You won't miss this pair of socks") to fit more signal into smaller bandwidth... HDV takes it even further - compressing the already chroma compressed signal into MPEG2...

Patrick

Hows bout this... throw it all out but the project file and keep the original tapes!!!

rh