Why the DVD project is double the size of the mpg files ?

[bambam]

Hi
I am trying to create a dvd using some mg1 file (with a quality of about 1000 kbps). The size of the 3 mpg files are 2.55 Gb. When i go in Ulead DVD Movie Factory it says that the project i am doing i 4.7 Gb !!!
Can you tell me why it's getting so big and what is the extra 2.15 Gb used for ? I tought the menu and chapters was only taking a few Mb

[guns1inger]

Movie Factory is probably converting your mpeg-1 files to mpeg-2, and may also be changing the resolution. I assume these were VCD resolution files ? Movie factory will be trying to create DVD compliant files at full resolution and higher bitrate.

[mats.hogberg]

Yes, UMF is most likely reencoding your source. Use a "real" authoring app like TMPGEnc DVD Author, that ,unlike editor/authorer combos, will just accept or reject the sources depending on if they are up to DVD specs. If they aren't, you'r3e better off reencoding your sources to DVD spec yourself, before trying to author them again.

/Mats

[drjtech]

Also, your audio is probably being converted to LPCM. That alone can cause a massive increase in file size.

-drj

[Capmaster]

Yes, UMF is most likely reencoding your source. Use a "real" authoring app like TMPGEnc DVD Author, that ,unlike editor/authorer combos, will just accept or reject the sources depending on if they are up to DVD specs. If they aren't, you'r3e better off reencoding your sources to DVD spec yourself, before trying to author them again.

/Mats

Abandon DVDMF? A bit extreme, IMHO. DVDMF has an option to disable reencoding of DVD-compliant files. With it disabled it's no different than the "real" DVD authoring apps :P

[junkmalle]

I have Ulead DVD Movie Factory 2. By default it reencodes VCD MPEG 1 files to MPEG 2 but uses the same bitrate (1150 kbps). It also converts the 224 kbps MP3 audio to LPCM. That's what's responsible for the file sizes doubling.

You can force it to leave the audio as MP3 which most DVD players will play, but it's not within spec (LPCM or AC3) for NTSC DVD players. Press the little Project Settings (checkbox) button near the lower left hand corner. Press "Change MPEG Settings". Select "Customize". Select the "Compression" tab. Change the "Audio Format" to "MPEG Audio", and set the "Audio Bitrate" to 224 (same as the original VCD file).

[Capmaster]

I have Ulead DVD Movie Factory 2. By default it reencodes VCD MPEG 1 files to MPEG 2 but uses the same bitrate (1150 kbps). It also converts the 224 kbps MP3 audio to LPCM. That's what's responsible for the file sizes doubling.

You can force it to leave the audio as MP3 which most DVD players will play, but it's not within spec (LPCM or AC3) for NTSC DVD players. Press the little Project Settings (checkbox) button near the lower left hand corner. Press "Change MPEG Settings". Select "Customize". Select the "Compression" tab. Change the "Audio Format" to "MPEG Audio", and set the "Audio Bitrate" to 224 (same as the original VCD file).

Wrong. First of all, it's not MP3 audio, it's MPEG1-Layer 2, or MP2 for short. And this type of audio is compatible with every NTSC player made in the last 4 years or so. Only the earliest DVD rules mandated LPCM for audio, and it's handy for troubleshooting ....but LPCM is obsolete for DVDs.

Second, yes ...by default it reencodes. That's why there's an option so it doesn't reencode. Unless you're of the habit of always leaving app default settings as-is, this isn't an issue.

[junkmalle]

Even with the "do not convert compliant mpeg files" selected it converts MPEG 1 VCD files to MPEG 2 at the same bitrate and frame size.

[Capmaster]

Even with the "do not convert compliant mpeg files" selected it converts MPEG 1 VCD files to MPEG 2 at the same bitrate and frame size.

That's true. I so rarely do VCD I had forgotten that. VCD files are DVD compliant, but DVDMF only leaves alone compliant MPEG2 files. MPEG1 get encoded.

[kvlourash]

[quote="junkmalle"]I have Ulead DVD Movie Factory 2. By default it reencodes VCD MPEG 1 files to MPEG 2 but uses the same bitrate (1150 kbps). It also converts the 224 kbps MP3 audio to LPCM. That's what's responsible for the file sizes doubling.

I thought VCD audio was 44 K and had to be converted to 48K for DVD use???

[junkmalle]

I have Ulead DVD Movie Factory 2. By default it reencodes VCD MPEG 1 files to MPEG 2 but uses the same bitrate (1150 kbps). It also converts the 224 kbps MP3 audio to LPCM. That's what's responsible for the file sizes doubling.

I thought VCD audio was 44 K and had to be converted to 48K for DVD use???

OK, so it converts the sample rate too.

[mats.hogberg]

Even with the "do not convert compliant mpeg files" selected it converts MPEG 1 VCD files to MPEG 2 at the same bitrate and frame size.

How stupid can a video editor get? Why does it reencode, and why does it use the same bit rate as the mpeg1? Sometimes it seems like the folks at Ulead has no clue whatsoever as to what they're doing, and just tries to hide the fact behind a "cool" UI!

/Mats

[dvd3500]

VCD audio is not DVD compliant. It is 44.1 Hz and DVD is 48.

[mats.hogberg]

VCD audio is not DVD compliant. It is 44.1 Hz and DVD is 48.

Yes - and???

/Mats

[junkmalle]

Even with the "do not convert compliant mpeg files" selected it converts MPEG 1 VCD files to MPEG 2 at the same bitrate and frame size.

How stupid can a video editor get? Why does it reencode, and why does it use the same bit rate as the mpeg1? Sometimes it seems like the folks at Ulead has no clue whatsoever as to what they're doing, and just tries to hide the fact behind a "cool" UI!

/Mats

I've been playing around with MovieFactory 3 lately. Version 2 used to convert to MPEG2 during the "converting" phase (the progress bar labeled as such). Version 3 still says converting but given how fast it's going (about 10 seconds for a 4.5 minute video) it's probably only demuxing the video. As a comparison, a 352x240 29.97 fps Xvid AVI file of approximately the same length took about a minute to convert.

Oddly, AVICodec reported the video portion of the resulting VOB file as "MPG2", the original VCD file as "MPG1". Both were 352x240, 29.97 fps, 1150 kbps.

Since I don't have version 2 installed anymore I can't say for sure if it really reencoded the video portion of VCD files. If you have fully DVD compliant files it skips the "converting" phase altogether. I may have seen the converting message and assumed it was reencoding when it was only demuxing the video (and converting the audio from MP2 to LPCM).

[neomaine]

Sorry, have to correct the invalid points on MF2 re-encoding VCD regardless if the 'do not reencode compliant' is set. I've created lots of episode disks from when I used to capture in VCD in MF2. And fitting 9-10 episodes (avg 40-42 minutes sans commercials) was never a problem.

Here's what I do...if its a true VCD compliant file:

Tools:
-TMPGenc
-Besweet
-MF2

Basic How TO:
- Demux the VCD (I use TMPGenc demux)
- Use Besweet to change the audio from 44.1 to 48 (I've always used MP2 to help keep the file size down and make it DVD compliant and its never given me a problem)
- Re-mux the video and audio (good time to test the vid/aud sync to make sure)
- Create a template in MF2 to match the VCD spec if one doesn't already exists. I've modified mine to use MP2 audio in this case. Make sure to use the exact settings of your video and audio.
- Author your DVD!

Even given the above, you can still define your own custom settings (for instance setting your MPEG1 rate to 1800 if you wanted xVCD) and MF2 will NOT reencode if you have the 'do not convert' and the correct matching template selected. Still need to change the audio to 48Khz for compliance.

[neomaine]

Forgot something on the previous post...

MF2 will take care of the audio MP2 re-encode if that's what you have your templete and settings set to. I've had mixed results here on audio/video sync though. The quality has always been fine...for TV captures anyway. Not sure if it was the occasional dropped frame or what. Never looked that closely into it.

However, to eliminate the sync (or even a potential quality issue) I would still recommend using Besweet or other audio tool of choice for the audio reencode to 48K/MP2. The demux/re-encode audio/remux only adds a few minutes to your time per episode but to me is really worth it to avoid question later on.