[badtz]

is the max. capture in iMovie only 60 mins.? why? can that be extended?

any other limitations of iMovie that should be kept in mind?


how about iDVD limitations? [other then the fact only apple's internal superdrive works]

When using the DV camcorder, everytime I stop the video then restart it, will iMovie automatically make that it's own "segment" when imported?

is there anyway to overdub your own commentary over video in iMovie?

What's the maximum video length can iMovie import/use?

Is the audio re-encoded when imported into iMovie? While the movie uses a CBR for encoding?

For DVDs, can one DVD hold a variable amount of video [depending on encoding method] or is it always going to be the same maximum amount per DVD disk?


thanks for any help!

[MoparSteve]

Originally posted by Badtz:
When using the DV camcorder, everytime I stop the video then restart it, will iMovie automatically make that it's own "segment" when imported?

This is the only question I can answer. Yes, every time you stop recording will signal the beginning of a new segment

[Ken_F2]

For DVDs, can one DVD hold a variable amount of video [depending on encoding method] or is it always going to be the same maximum amount per DVD disk?

iDVD does not support variable bit rate encoding. That means any DVD you do with iDVD will be limited to a max of 60 minutes, because a single encoding bit rate used by the program (regardless of the scene complexity) that is tailored to fit 60 minutes on a DVD.

If you want more than 60 minutes, which variable bit rate encoding will provide, you'll need DVD Studio Pro.

[badtz]

is it 60 minutes? or 90 minutes max.???

isn't the encoding taking place in iMovie [not iDVD? or DVD Studio pro?]......??

[Hoosier_1701]

Originally posted by Badtz:
is it 60 minutes? or 90 minutes max.???

isn't the encoding taking place in iMovie [not iDVD? or DVD Studio pro?]......??

It is 90 minutes max with iDVD2. (iDVD 1.0 did have a 60 minute max if I remember right.) iDVD2 does a lighter compression for anything 60 minutes or less. Once you go over 60 minutes, it does a higher level of compression...but 90 minutes is the maximum.

iMovie actually exports the movies to Quicktime format. iDVD does the mpeg2 encoding. iDVD2 does encoding in the background as soon as you add a movie to your project.

[badtz]

any specifics on the encoding method of iDVD?

can iMovie export it as a DV stream into iDVD? exporting it as a quicktime, doesn't that mean it's compressing/encoding twice? once to quicktime, and again to mpeg-2?

[scottiB]

any specifics on the encoding method of iDVD?

can iMovie export it as a DV stream into iDVD? exporting it as a quicktime, doesn't that mean it's compressing/encoding twice? once to quicktime, and again to mpeg-2?

If you choose "(e)xport to iDVD" from iMovie (which is all settings at their highests), your QuickTime movie will have a throughput of roughly 3.53 megabytes (or 28.24 megabits) per second. Maximum DVD-Video standard throughput is 1.225 MB/sec (or 9.8 Mb/sec), so iDVD compresses it to either 1 MB/sec (8 Mb/sec) for <= 60 minutes of video or .625 MB/sec (5 Mb/sec) for <= 90 minutes of video.

A 60 minute MPEG-2 would yield a size of roughly 3.6 GB (1 MB/sec x 60 sec/min x 60 min), and a 90 minute one would be 3.375 GB (.625 x 60 x 90). Obviously these can both fit onto a 4.7 GB DVD-R with room for menus, themes, etc. As was mentioned above, iDVD isn't capable of VBR, so this is a limitation; however, both compression ratios are above 60% (well above for video <= 60 min.) so the results should look pretty to very good. FYI, a 4.7 GB DVD can hold approx. 64 minutes of video at the lightest compression (9.8 Mb/sec).

Regarding encoding twice (from .dv to .mov to .mpeg2), the compressing is stair-stepping down in quality, so it's not an issue. If you compressed from high quality QT to MPEG-1 then up to MPEG-2, it'd look terrible.

[badtz]

scott, thanks for the good info..

but......


stair-stepping compression -->> that's still TWO phases of compressing......

Is there anyway to bring a DV stream from iMovie straight into iDVD [as a dv stream] and have iDVD do the mpeg-2 compression, so it only goes through ONE compression?



Also ::: @ 9.8Mb/sec encoding [lightest compression], is that for CBR or VBR? are real DVD movies encoded @ this setting?

[scottiB]

Reverse order:

Also ::: @ 9.8Mb/sec encoding [lightest compression], is that for CBR or VBR? are real DVD movies encoded @ this setting?

That is the maximum throughput assigned to the DVD-Video standard--meaning that a higher throughput would bog down DVD players--at least in theory. Whether it be CBR of VBR the throughput should never surpass that threshold according to the standard. Since at the 9.8 Mb/sec setting, a single layered DVD could only hold 64 minutes (a double layered 128 minutes), commercial DVDs are less than that to handle all the extras, menus, various audio options, etc.

To throw some more math around--since American DVDs are ± 30 frames per second, each frame at the lightest compression would be ± 41 kilobytes (41 KB/sec x 30 frames/sec x 1 sec x 8 bits--to convert to megabits ÷ 1000--to get megabits--I know its really 1024 :-)). That's not really big for an image frame. I would suppose that, depending on what's included on the disc, commercial DVDs are VBR in the 5-7 Mb/sec range--variables include whether both wide and full screen versions are included (the biggie, I would think), number of deleted scenes, etc. Compressing is very much nuance and artistry, and the pros have all the tools and hardware needing to maximize quality in the space constrictions.

Just thinking out loud, I would suspect that a full screen file is quite a bit larger than wide screen. The wide screen is mostly black--which the VBR handles nicely, I would think. I'm no DVD author, but it would make sense.

stair-stepping compression -->> that's still TWO phases of compressing......

Is there anyway to bring a DV stream from iMovie straight into iDVD [as a dv stream] and have iDVD do the mpeg-2 compression, so it only goes through ONE compression?

I understand your implication but having a middle step doesn't harm the final MPEG-2. Say, you need a 20 KB jpeg for a web page and create it in PhotoShop. The .psd file is 4 MB and you save it as the 20 KB .jpeg. If you save the .psd file as a TIFF at 2 MB, then save the TIFF as the 20 KB .jpeg, I bet that there'd be no discernable difference. That amount of compression to .jpeg is high enough (and the file size low enough) that it really doesn't matter.

In saving the DV stream to a .mov first, iMovie creates a portable format with good quality that is above the MPEG-2 quality threshold. I guess what I'm saying is that, even if feasable, compressing directly from a DV stream doesn't gain you anything.

[badtz]

thanks for all the great 411!

[joe_mc]

[QUOTE]Originally posted by Badtz:
[B]scott, thanks for the good info..

but......
stair-stepping compression -->> that's still TWO phases of compressing......

Is there anyway to bring a DV stream from iMovie straight into iDVD [as a dv stream] and have iDVD do the mpeg-2 compression, so it only goes through ONE compression?


Hi,
this can be don quite easily and less time consuming if you have got Quicktime Pro.
First: edit your movie in imovie, make sure the trash is empty (may take a while)
second: look at the numbering of the clips in the timeline 1.2.3..etc.
save your project.
third: open your project folder (my great movie or whatever), inside there is the media folder, open that too and you will see all your clips. Select them all and drag them onto the quicktimeplayer to open them. Now take the first one,
scroll though to the end, and activate the second clip (player window), hit "select all" from the menu and then copy. Return to the Playerwindow with the first clip and paste the second in. Same goes for the following clips always append to clip one at the end.

When your ready save your movie (clip one with all the pasted clips) not selfcontained but "allowing dependencies" which results in a small movie file with references to the original clips.
This clip can be dopped on idvd and it will encode the whole movie. No export-step between and when you get used to it far faster than exporting the whole thing from imovie.

[badtz]

joe....

I understand all of what you said, EXCEPT this part......

"Now take the first one,
scroll though to the end, and activate the second clip (player window), hit "select all" from the menu and then copy. Return to the Playerwindow with the first clip and paste the second in. Same goes for the following clips always append to clip one at the end.

When your ready save your movie (clip one with all the pasted clips) not selfcontained but "allowing dependencies" which results in a small movie file with references to the original clips.
This clip can be dopped on idvd and it will encode the whole movie. No export-step between and when you get used to it far faster than exporting the whole thing from imovie."

[joe_mc]

Originally posted by badtz:
joe....

I understand all of what you said, EXCEPT this part......

"Now take the first one,
scroll though to the end, and activate the second clip (player window), hit "select all" from the menu and then copy. Return to the Playerwindow with the first clip and paste the second in. Same goes for the following clips always append to clip one at the end.

When your ready save your movie (clip one with all the pasted clips) not selfcontained but "allowing dependencies" which results in a small movie file with references to the original clips.
This clip can be dopped on idvd and it will encode the whole movie. No export-step between and when you get used to it far faster than exporting the whole thing from imovie."

ok, perhaps a difficult text for something easy to do, just wanted to make sure.

you have got all your clips open in seperate Quicktime Player Windows.
move the slider (little triangle in the timeline of the player) to the end of your first clip, really the end not a second earlier.
in your clip2 you hit select all from the menu or (AppleKey-A) then copy to clipboard (Apple-C)
switch back to your first clip, and paste in (Apple-V), now you ve got both clips
in your first player. Now you can save them, the save-dialog will give you two options : self contained (big size) or "allowingdependencies" (small size).
select the small size option. the resulting movie (small) can be dragged onto iDVD.
To add more clips to your movie just repeat the second step as long as you have clips left ; )

Hope this was easier, dont know why this option is not availabe in iMovie itself, would take away the long saving process.
joe

[badtz]

what's the difference between "self-contained" and "allowingdependencies" ?

also, when imported into iDVD, is it in two clips? or as one big clip?

couldn't you bring it into iDVD as many separate clips?

thanks

[joe_mc]

Originally posted by badtz:
what's the difference between "self-contained" and "allowingdependencies" ?

also, when imported into iDVD, is it in two clips? or as one big clip?

couldn't you bring it into iDVD as many separate clips?

thanks

no, when imported in iDVD it is one big clip, if you like to have seperate clips, then you just have to save each clip on its own.
Maybe iDVD also accepts the original clip files, havent tried. If it does not, just open them with QT Player and the save as dependend file, which can then be dropped on iDVD.

The difference between the two saving modes:
self contained saves your two clips (now merged) into one big new file.
takes long, as all the data must be copied into the new file (thats the same process iMovie does when you select "export to iDVD"
dependencies: saves a movie which basically has an alias to the clips in it (do not delete the originals or you will an error message), therfore its smaller and saves in a snap.

[nitram_at_work]

About "Exporting to iDVD from iMovie and compressing twice".

AFAIK, when you "Export to iDVD" from iMovie, you are not compressing it. iMovie takes all of your clips, sounds, transitions etc and creates one uncompressed clip (apart from the DV compression that is already present). It's a file-creation process.

When you create the iDVD, THEN the file is compressed/converted to MPEG2.

iMovie "iDVD export" -> creates a single file from your bits and pieces
DVD creation in iDVD -> turns an uncompressed file into an MPEG2 suitable for DVD (and of course iDVD does all the burning, buttons, etc)

[badtz]

so tehre's an export to iDVD option in iMovie?

[train]

Originally posted by badtz:
so tehre's an export to iDVD option in iMovie?

Yes.

[scottiB]

Nitram is correct--and thanks for clarifying. What the iMovie's doing is rendering the .mov, not compressing it, as such. It still takes some time--hours--to create a 60 minute .mov at the iDVD setting.