dv avi ---> dv mov mpeg streamclip question

[BabaG]

i have a pile of dv avi files captured in scenalyzer via firewire. they need to be converted to mov for use in final cut pro. the process of sorting, categorizing, and librarying the files will be cumbersome and i anticipate organizational issues which may mean i'll find i need to go back to avi's once in a while after the conversion.

the nature of what i'm doing is such that it would be much easier to simply reconvert the mov's back to avi, do the work, then reconvert to mov again. i don't want to go through all the converting and reconverting, though, unless i know it's being done in a lossless manner.

it's my understanding that dv files meet a common spec and that the container's header info is really all that's different between a dv avi and a dv mov file. assuming that's the case, it should be pretty painless to do multiple conversions.

i'd like to use mpeg streamclip for converting as it's available cross-platform and is easy to use. i haven't seen any info on whether a straight across conversion like this is carried out in a lossless manner by mpeg streamclip, though. does anyone know if this is the case? or, alternately, can anyone suggest something else free that can go both was in a lossless manner like mpeg streamclip?

thanks,
BabaG

[JohnnyMalaria]

If MPEG Streamclip isn't lossless (I think it is), our software (in signature) can convert to/from DV AVI and raw DV files (which I understand are supported in FCP). Note, it is Windows-based.

[dr.schanker]

Give ffmpeg (http://sourceforge.net/project/showfiles.php?group_id=205275&package_id=248632) a try. It's a very powerful and free command line transcoder. You could write a small and simple batch file for mass conversion.

Basic examples:

mov2avi
ffmpeg.exe -i "input.mov" -vcodec copy -acodec copy -y "output.avi"

avi2mov
ffmpeg.exe -i "input.avi" -vcodec copy -acodec pcm_s16le -y "output.mov"

[BabaG]

thanks.

dr. schanker, ffmpeg is lossless?

BabaG

[Mug Funky]

when -vcodec is "copy" then it is lossless - it copies the compressed stream and stuffs it into the new container.

[edit]

btw, i though FCP could load DV-in-AVI files? if so you could simply drop everything in and mediamanage to .mov.

though it's probably not that easy :)

[BabaG]

thanks mug funky.

for whatever reason, fcp is rejecting these avi's. different versions of fcp seem to sometimes accept them, sometimes reject them. postings i've made to fcp groups have simply said to stay away from avi's. not very helpful as it doesn't help to understand why this happens but, if you're stuck with fcp, seems to be the attitude and level of help so that's why seeking the workaround.

thanks again,
BabaG

[SeeMoreDigital]

Hi BabaG,

I work with miniDV and DVcam tape formats, together with DV.avi and DV.mov sources sent to me on disc or download link....

I can confirm that QuickTime Pro is able to re-mux DV.avi sources to DV.mov without re-encoding. And MPEG Streamclip is able to re-mux DV.mov sources to DV.avi without re-encoding.


Cheers

[BabaG]

thanks SeeMoreDigital.

quick question, since you can confirm lossless dv.mov--->dv.avi in mpeg streamclip, can you also confirm the reverse, that is lossless dv.avi--->dv.mov using mpeg streamclip? i ask because of mpeg streamclip's batch capabilities. qt pro requires applescripting or some other such workaround for batch work as i understand it whereas mpeg streamclip has batch built in.

thanks again,
BabaG

[nhope]

I tried to do a lossless remux of PAL DV .avi to .mov by doing simply "Save as" to .mov in MPEG Streamclip and Quicktime Player, and by a like-for-like export in MPEG Streamclip. I also did it with FFMpeg by using a straight "-vcodec copy" command line as described above. But in each case I get a significant and unacceptable increase in brightness. Blown out highlights and an increase in contrast.

I also see this same increase in brightness when I play the original .avi file in Quicktime Player. So it seems to me that instead of doing a simple remux, each of those methods is reading the .avi and somehow changing the luminosity before muxing to .mov.

Anyone know why this is happening and if it can be avoided?

:thanks:

[dr.schanker]

I am quite sure that all the methods you described give you an unprocessed remux, the problem seems to be the Quicktime DV-Decoder or some incorrect Quicktime playback settings (try to switch from DirectX to GDI mode).

Use the free VLC-Player (http://en.wikipedia.org/wiki/VLC_media_player) to check your file. VLC plays .mov files and uses its internal libraries for decoding (thus circumventing the installed Quicktime framework). If it plays correctly in VLC then there is QT to blame.

You could install the latest Quicktime version, maybe that fixes the DV-Decoder issue. Good luck.

[Ghitulescu]

for whatever reason, fcp is rejecting these avi's. different versions of fcp seem to sometimes accept them, sometimes reject them.

Maybe because there are two flavours of DV AVIs, type 1 and type 2.

[nhope]

Thanks dr.schanker, Same result in Quicktime with either GDI or DirectX mode. Quicktime version is 7.6.2. Later versions cause problems with Vegas. I doubt there's a difference in this issue since 7.6.2 (unless someone knows better).

I tried VLC as you suggest and the "simple remux" versions do look the same as the original but my Vegas-encoded version looks darker. It's very confusing now to understand what is happening. Seems to be a combination of decoding and display issues.

I have several thousand DV avi > mov conversions to do for a stock footage distributor. I guess I should probably just do it the "simple remux" way, theoretically the least lossy way, and accept that the luminosity on the end users' systems is somewhat out of my control.