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What video format does Multiquence 'prefer' to work with?

Posted: Wed Feb 09, 2005 3:33 pm
by Felix
I'm thinking of buying a video capture device with the intention of using Multiquence to play around with the captured video.

Just wondering which video file format Multiquence would ideally like to work with from scratch with respect to the final quality of its output. I suppose it would be the RGB uncompressed one but that isn't practical for long clips. Is plain MPEG the next best bet? I'm guessing something that hasn't been compressed too much because Multiquence would have to decompress it before mixing and then re-encode with a loss in quality at each stage.

I ask also with respect to putting the least strain on the processor when previewing the project in Multiquence (real-time mixing). What's the best input video format to use?

I'm looking at a card which has hardware MPEG1/2 encoding. Is that a good choice?

Any advice?

Btw, is it normal that outputting to a DivX .avi only compresses the video and not the audio, therefore leaving the file much larger than you would expect for a DivX. (Actually I don't think this is specific to DivX codec, but to codecs in general when outputting to .avi).

Re: What video format does Multiquence 'prefer' to work with

Posted: Thu Feb 10, 2005 9:48 am
by Stiiv
Felix wrote: Btw, is it normal that outputting to a DivX .avi only compresses the video and not the audio, therefore leaving the file much larger than you would expect for a DivX. (Actually I don't think this is specific to DivX codec, but to codecs in general when outputting to .avi).
If you're referring to output from MQ, then yes, it's normal. MQ doesn't do compression on avi audio.

Re: What video format does Multiquence 'prefer' to work with

Posted: Thu Feb 10, 2005 5:00 pm
by GoldWave Inc.
There is no preferred internal format for Multiquence. Using high bitrates when capturing to preserve as much quality as possible (in any format) is recommended.

Cards that supports MPEG2 decoding internally are not recommended since it may not be possible for Multiquence to retrieve the decoded frames for editing. ATI TV cards, for example, prevent Multiquence from working with MPEG2 video. They pass decoded MPEG2 video directly to video hardware for display only (possibly due to restrictive DVD copy protection requirements). Installing a separate software MPEG2 decoder can avoid that problem. Using MPEG1 encoding (in hardware or CPU) usually works well, though quality and file size may not be ideal.

Multiquence does not have the ability to compress audio in AVI files. Saving in WMV or MOV formats instead of AVI is recommended.

Chris

Re: What video format does Multiquence 'prefer' to work with

Posted: Fri Feb 11, 2005 10:14 am
by Felix
Thanks for your replies. Just for clarification:
GoldWave Inc. wrote:Cards that supports MPEG2 decoding internally are not recommended since it may not be possible for Multiquence to retrieve the decoded frames for editing.
I take it you you are talking about graphics cards which support internal DECODING? I think I'm safe on that front because I have Intel Integrated Graphics 855GME on my machine. My question was regarding the capture device supporting internal ENCODING. I assume this has no bearing on the output file format and Multiquence's ability to work with it - it's just a feature that takes the load off the processor when capturing video?

Re: What video format does Multiquence 'prefer' to work with

Posted: Fri Feb 11, 2005 9:52 pm
by GoldWave Inc.
Cards that do internal encoding tend to do internal decoding as well, but it really depends if they allow other programs to access the decoded video or if they have restrictive copy protection in place. Multiquence relies entirely on Windows decoders to get raw video data. If the primary MPEG2 decoder installed on your system allows programs to receive raw data, then that will work.

Chris

Re: What video format does Multiquence 'prefer' to work with

Posted: Sat Feb 12, 2005 2:49 pm
by Felix
GoldWave Inc. wrote:Cards that do internal encoding tend to do internal decoding as well
Really? I didn't know that. I was actually looking at an external capture device (USB or PCMCIA) as it will be used with a laptop. Given that such a device is removable/hotpluggable, I would presume it wouldn't encode anything in such a way that the file would be dependant on the capture device being present in order to be played back (decoded)?
GoldWave Inc. wrote:If the primary MPEG2 decoder installed on your system allows programs to receive raw data, then that will work.
My computer came with Cyberlink DVD installed which I presume offers MPEG2 decoding? Would that be alright?

Re: What video format does Multiquence 'prefer' to work with

Posted: Mon Feb 14, 2005 10:39 pm
by GoldWave Inc.
If it is a "capture only" device, then that would not be a problem.

The only way to know for sure if Multiquence will be able to work with MPEG2 files is to add such a file in the program and see if the video frames appear. Some configurations give audio only or you just get an error.

Chris

Posted: Tue Mar 22, 2005 7:57 am
by Bandung
I like to use MJPEG codecs for capture. The PicVideo codec is pretty fast and so is Morgan's recent release. Every frame is an I frame which makes it ideal for editing. I crank the quality up as much as I can.

The disadvantage that I've seen with the earlier versions of videos encoded with a mjpeg codec is some colour transformation issues. If you know how to use avisynth, there are some simple scripts for getting around these colour problems. The other problem is that when I transcode to another compression codec, I "lose" detail since the mjpeg standard uses an avisual-perception algorithm that another codec sees as "lost information"

Over time, I intend to use the DV codec more and more since I can also archive great gobs of material to DV tapes without any quality losses.