I am in the process of digitizing a bunch of DV tapes, and I now have them as DV files (I imported them using an app called Vidi on the mac). I want to add chapter markers to the files, which requires that they be in a MOV container. My issue is that every app that I have tried to put the DV files into MOV containers exactly doubles the files (so a 2gb DV becomes a 4gb MOV). Since I am not transcoding the files, just changing containers, I dont see why the file size should change so dramatically. I read on another forum that mov keeps two copies of the DV stream- one for the video track and one for audio. Is that right, and if so is there any way around it? Thanks!
Try StreamFab Downloader and download from Netflix, Amazon, Youtube! Or Try DVDFab and copy Blu-rays!
+ Reply to Thread
Results 1 to 8 of 8
Thread
-
-
Why did you choose not to use a mainstream app like imovie?
Using what software, vidi?
Which EVERY app have you been using?
It shouldn't, suggesting that either the input or the output is something other than standard DV.
That's not right. Certain versions of certain containers will keep a second copy of the audio. -
I didn't use iMovie because it was giving me issues, one of which was crashing in the middle of the import and having to start over again several times. I gave up on it, and vidi has been much more stable for me. I have tried converting the file with quicktime 7, as well as QT edit, mpeg streamclip, and SimpleMovieX. If I "export" the file to quicktime instead of just saving as a MOV, I can get the file size around the same as the original DV file, but this means I have to transcode the file and am degrading the quality. When I have time ill cut off a piece of one of the DV files if you want a sample to try.
I ran one of the DV files through MediaInfo:
-
Wow. You are correct -- looks like QT DOES double the video track to create the audio track. I guess none of my normal processes have taken me this particular route -- or I simply haven't noticed.
Without getting into a high-end NLE simply for remuxing, you might want to try something like ffmpeg and a command line like this:
ffmpeg -i 123.dv -vcodec copy -acodec copy -f mov 123.mov -
-
I've done research on this very problem before and here's what I've found:
Just like in PC AVI-land, where you can have 3 kinds of DV files:
1. The raw DV stream (known as a DIF stream), which has the video and audio data and user data (cam data, timecode, etc) muxed together
2. The same raw stream encapsulated into an AVI container, but otherwise unchanged. Known as a DV-AVI Type1. The muxed stream is headered as an IAVS or IVAS (interleaved video-audio stream).
3. The audio stream is read and copied into its own elementary stream and then both the original muxed stream and the copied audio stream are encapsulated into an AVI container. The muxed stream is given the header designation "vids" and the audio copy stream is given "auds", so that all apps will read the video fine (ignoring it's in-muxed audio) and read the audio copy fine, but it does enlarge the filesize.
QT MOV on Macs (and PCs) do the same thing:
1. Raw DV
2. Type1 MOV
3. Type2 MOV
As noted in this previous post of mine: https://forum.videohelp.com/threads/323971-How-Do-I-Play-Raw-DV-Stream-Files-on-a-TV?p=...=1#post2095616, there is a bug in QT that doubles the streams dumbly. It can be processed to fix it WITHOUT LOSS of the original quality. Note also a 2nd bug happening in MpegStreamClip. I believe yours is one of those outcomes.
Since that last thread, alot has been done to improve ffmpeg (but alas, NOT so with Quicktime or MpegStreamClip), so I think your conversion script is probably the best choice for cleaning files such as these up. YMMV.
Scott -
That's interesting Scott. I normally go directly into an NLE with the DV stream, or do the conversion with ffmpeg because it's fast, so I had never noticed this before. Looks like I also missed your earlier post on this topic. (I was lurking a long time before I joined.) Thanks.