Which format is the best ?

babdi · Post by **babdi** » Sat Sep 29, 2007 3:22 am

Which format of Video & Audio are uncompressed ?

Which video format is supposed to be the best in terms of quality and which are supposed be best in terms of audio quality.

Does the best video or audio format make huge file sizes by virtue of not be compressed ? If yes which of the uncompressed video & audio file formats
have smallest file sizes

Clevo · Post by **Clevo** » Sat Sep 29, 2007 3:46 am

Hi babdi,

This is not really a video studio related question and....

This is a difficult question to answer and there is lots of information on the internet.

To me, quality has more to do with how it's been captured and the equipment used to capture and store.

On a consumer level. I intentionally bought a MiniDV Tape camcorder because after reading a lot of info I wanted DV-AVI format files to work with.

Anyway..I could go on and here are a few sites to read:

This one is handy:

http://www.cyberlink.com/english/dv-ent ... format.jsp

heinz-oz · Post by **heinz-oz** » Sat Sep 29, 2007 4:21 am

The file size of video/audio files are governed by their frame size, frame rate and color depth in case of video and the sampling rate in case of audio.

Uncompressed video is around 65 GB/hour plus the audio.

Capturing your video from any source, you are well advised to stick with the native compression codec used. DV-AVI is the most usable format for editing and is native to MiniDV camcorders. It has a compression rate of around 10 to 11% but is lossless in its first generation. It comes in at around 13 GB/hour. Mpeg2 is another but only editable when recorded with high bit rates. Low bit rate mpeg2 is bound to cause you problems when edited.

Capturing from any compressed source to uncompressed file formats is only going to stretch your resources since the captured content cannot be better than the original because the additional data has to be guessed by the program.

Post by **Ken Berry** » Sat Sep 29, 2007 4:30 am

As far as I am aware, only raw AVI video is uncompressed. Its files are huge -- 65 GB per hour of video. After that, all video formats have varying degrees of compression applied using different sorts of algorithms which leave them either virtually lossless (DV or MJPEG) or lossy (mpeg-1, mpeg-2, mpeg-4, DivX, XVid). DV comes in one quality variety only, but all the others can have their quality changed by the bitrate applied and the frame format size. All of the lossy formats are capable of quite high quality apart from mpeg-1. But they are meant more for final display rather than being suitable for editing.

Of the audio formats, I think that only .wav and its DVD equivalent (L)PCM (which is the audio format used with DV video) are not compressed but could be wrong about the latter -- certainly the bitrate associated with LPCM can be changed. Hopefully someone more knowledgable about audio will jump in here. LPCM audio seems to be the highest quality for DVDs, but creates relatively large files. Some of the other formats (Dolby, mpeg-layer 2) are capable of high quality but are much more compressed.

But in one sense your question has no meaning since you do not give a context. If you are talking about video and audio for DVDs, then the format and compression you use must conform to international DVD standards. Standard video DVDs must use mpeg-2 video, but the quality/bitrate settings can vary downward from 9200 (I think) kbps for the combined video and audio. The frame sizes are also fixed for NTSC or PAL. And the audio must be (for home videos at least) LPCM or Dolby (dual channel or 5.1) or mpeg layer 2 audio for PAL, but only LPCM or Dolby for NTSC (though in practice most modern NTSC DVD players will also play mpeg layer 2 audio.

Then there is the whole new ball game of Hi Def and Blue Ray discs, a subject about which I cheerfully admit total ignorance!!

An increasing number of DVD players are also rated to play DivX CDs and DVDs. These are highly compressed and you can fit roughly 5 x 90 minute movies onto one DVD at good quality.

Hopefully some of this may have been useful to you. But if not, as Clevo has already suggested, it is more a topic you can research through Google.

babdi · Post by **babdi** » Sat Sep 29, 2007 4:30 pm

Thank you all.

We seem to have agreement with disparate opinions.

The confusion seemingly lies with multitude of video & audio formats.
It would really be heartening for us that people professing different formats
agree on a common "codec" which is light on file size, easy editing and at the same time give good quality worth watching and hearing.

I would like to add that there was a move to agree on a common platform in HD broadcasting. However we see 2 distinct format. As the technology goes bounding we will see less of multiplicity and will end with maybe 1 format

Thank you once again for the useful discussion

heinz-oz · Post by **heinz-oz** » Sat Sep 29, 2007 4:43 pm

Yeah, and Pigs might fly one day

PuzZLeR · Post by **PuzZLeR** » Sat Sep 29, 2007 5:42 pm

I know it may seem overwhelming and seem like fragmentation of format, but the way I look at it is that each has its purpose.

The more uncompressed your source, such as raw AVI, or virtually lossless DV, the easier to edit. This is because the key frames are closer together among other reasons.

The way I look at it is that you only go to MPEG-2 once you've decided on your final edits and want to compress it to a more manageable file size with a very reasonable small quality loss. It also comes in handy for conventional DvD playback. The only reason I edit MPEG-2 at all is because some of my content is from my DVR, which only writes to MPEG-2, assuming its creating a "final DvD" for me, and I have little choice.

If you want even more compression you use DivX and Xvid. These codecs have much higher efficiency than MPEG-2 with compression - more quality per file size, but are even worse for editing (and although have support with the stand-alone market, still not as wide as MPEG-2 support). You better make sure that your edits are final before going to this format. Heck, even MPEG-2 is problematic with edits as I'm discovering in a recent thread.

But if you want to be super-ambitious and get the maximum quality and smallest file size you go with a modern codec like H.264. I'm warning you though, support for it still weak (but growing) and encoding to it is very CPU intensive - expect overnight encodes for just one hour of video with a Core 2 Duo processor. As well, now, more than ever you better be sure of your final edits because editting this format will be a nightmare today.

However, these problems are really only short term with H.264.

If you want to find your "common codec" that you mentioned, and wish to archive video, the future is indeed H.264. The market and hardware will adapt to it, and keep in mind, although it has a funny name it *IS* an MPEG codec (MPEG-4 Part 10 AVC ISO/IEC 14496-10 to be exact according to the standards). This is the MPEG of the future and is a standard with blu-ray and HD-DvD as well.

Maybe the pigs will be flying in the H.264 direction in about 5 years.... hopefully...