DVD Flick weirdness

[apb3304]

I just d/l'ed DVD Flick. I'm trying to burn to a 700 MB CD. Yes, it's old (but brand new if that makes sense).

What I don't understand, is the file I want to burn is 70 MB, and Flick tells me that the disk is 98% full. 70 MB is not 700 MB. Yes, this is a blank disk fresh out of the "box".

What gives?

Thank you in advance.

[Just Playin]

DVD Flick is for producing DVD Video discs. You need to use DVD discs, not CD discs.

[apb3304]

If I'm not supposed to use CD discs, then please explain the purpose of the dropdown menu that lets me select a "target size" of "CD-700 (700 MB)" in the project settings "general" tab.

[Just Playin]

I stand corrected.
There is nothing wrong with the disc or DVD Flick. DVD Flick re-encodes your clip to DVD Video specs(MPEG2 video and AC3 audio). That is why your 70MB video file ends up larger after the conversion.

[apb3304]

That's what I figured, but I'm still puzzled.

The source file is 70MB. You're saying it increases the file size by nearly 10 times, to nearly 700MB in order to create an MPEG2 (and associated audio)file? That seems excessive. (For the record, I'm trying to burn a .avi file.)

Further, that would imply that even if I did in fact use a DVD disc with a 4GB capacity, I could only burn a (.avi) file with a maximum size of 400 MB as it would create a 4000 MB MPEG2 file. 4000MB=4GB of course.

Is that what you're saying?

Are those the kind of results you get? You can only burn one 400MB file per 4GB capacity DVD disc?

[Just Playin]

Not exactly. It doesn't correlate exactly like that. The MPEG2 codec is one of the oldest and is much less efficient than many of the newer codecs introduced afterward. The better the codec in your source file at compressing video information, the larger the MPEG2 file will need to be to hold that same information.

Anyway, DVD Flick's default is to automatically calculate a bitrate optimized to fill the destination disc with the best quality video without dropping below a limit of 2Mb/sec. Add another video and DVD Flick will recalculate a new bitrate unless that final bitrate is less than 2Mb/sec. If you add too much video to achieve that minimum bitrate on your target disc, DVD Flick will warn you to remove clips or you will need to manually set a lower the bitrate to fit it all.

[apb3304]

First I need to correct what I stated earlier. The file is .mkv format. Since most of my files are .avi I simply assumed instead of checking. I've now checked.

According to VLC player, my .mkv video file uses the MPEG4 codec.

So, if I understand correctly, any file encoded with MPEG4, is going to expand approximately 10 times when re-encoded with MPEG2?

Again I ask, is this what you're seeing with your files? A 10 to 1 expansion? And therefore I can expect to store a maximum of about 400MB per 4GB DVD disc?

[Just Playin]

Originally Posted by apb3304

First I need to correct what I stated earlier. The file is .mkv format. Since most of my files are .avi I simply assumed instead of checking. I've now checked.

According to VLC player, my .mkv video file uses the MPEG4 codec.

So, if I understand correctly, any file encoded with MPEG4, is going to expand approximately 10 times when re-encoded with MPEG2?

Again I ask, is this what you're seeing with your files? A 10 to 1 expansion? And therefore I can expect to store a maximum of about 400MB per 4GB DVD disc?

There is no set ratio. The size of the source file is not only factor but also the bitrate and resolution of that file. Two source files the same size but encoded to different resolutions and bitrates will produce different results on a finished DVD Video disc.

[apb3304]

Right. I should have said assume (for the sake of this discussion) that the bitrate remains the same for all files. It seems as if bitrate is dependent primarily if not entirely, on resolution - yes?

So if bitrate is constant (and so is resolution) for each file, and each file is using MPEG4 encoding, then the most I'll be able to store on a 4GB DVD is 400MB. Yes?