why does file size increase so much when trying to burn????

[BabyDaddy]

Hello. I am using cyberlink powerdirector and am happy with how I can edit my projects. BUT when it comes time to burning my project on a blu-ray, for some reason it increases my original file size WAY to high. I have mp4 videos totaling 9GB and trying to burn them on a 25GB blu-ray. Should be no problem right? But I cant figure out why powerdirector turns that 9GB into 68GB!!!!! At default settings it boosted it to over 100GB!! With the few amount of settings available, the lowest I can get it is 68GB. Can anyone explain what is going on????? I dont want to pay for any other software, so if powerdirector doesnt have the ability to do this, is there a good, free third party blu-ray disc creator I can use instead?

[DB83]

To attempt to answer your main question.....


It's all down to bitrate. Now answer this. How long do your 9GB of video take to play ?. Blu Ray has a maximum video bitrate of 40 MBit/s and will also require a minimum bitrate (forget that right now but assume 25 MBit/s). Now multiply your total run time, in secs, by 40, or even 25, and you will no doubt exceed your 25 GB and that does not even take the audio in to account.


You can look at the software page for any free blu ray authoring but if you fail the above test they will not help you.


Your only recourse is to split the videos on to more than one disk.

[BabyDaddy]

Thank you for your reply. The average bitrate for each of my videos is only 1100... for some reason I am unable to upload an attachment here but I will tell of two blu-ray discs I have that someone else made. One is a 50GB disc. There are 71 m2ts files totaling 43GB for 23 hours of material at an average bitrate of 4300!! The other is on a 25GB disc. There are 35 m2ts files totaling 21.4GB for nearly 12 hours of material at an average bitrate of 4300 as well! (plus audio on both)...... So my project is smaller and at the very least, should fit on a 50GB disc if not a 25GB one. So I still dont understand why cyberlink powerdirector is ballooning my project from 9GB to over 68GB when I try to create a disc.

[davexnet]

The usual thing is the bitrate. If you edit a project in PD and rendered it out,
you set the bitrate too high

[DB83]

Forget the bitrate of your own videos. As I already wrote all that matters is the bitrate of the encode.


Now there may well be no de-facto minimum bitrate - as long as it plays then that is all that would matter but consider this. A SD dvd has a maximum video bitrate of a little over 8000 kbps compared with blu-ray of 40000 kbps. The typical bitrate for a dvd is 5500 kbps which would give you about 100 mins of video or a basic full movie. Yes, you can reduce that bitrate and dvd has other settings to get about 10 hours on a disk. And the majority of authoring programs will not let you get even close to that.


Now PowerDVD may well allow you to encode your video outside the blu-ray part of the program at 4300 kbps. Now as long as these independently encoded videos meet the blu-ray spec they might not re-encode the video again - some programs do, some do not. But what it is doing is encoding at a more typical bitrate that you would find on a store-bought disk.


And BTW you make no friends around here, especially from the mods, by starting new topics about the same issue and over different forums.

[BabyDaddy]

Forget the bitrate of your own videos. As I already wrote all that matters is the bitrate of the encode.


Now there may well be no de-facto minimum bitrate - as long as it plays then that is all that would matter but consider this. A SD dvd has a maximum video bitrate of a little over 8000 kbps compared with blu-ray of 40000 kbps. The typical bitrate for a dvd is 5500 kbps which would give you about 100 mins of video or a basic full movie. Yes, you can reduce that bitrate and dvd has other settings to get about 10 hours on a disk. And the majority of authoring programs will not let you get even close to that.


Now PowerDVD may well allow you to encode your video outside the blu-ray part of the program at 4300 kbps. Now as long as these independently encoded videos meet the blu-ray spec they might not re-encode the video again - some programs do, some do not. But what it is doing is encoding at a more typical bitrate that you would find on a store-bought disk.


And BTW you make no friends around here, especially from the mods, by starting new topics about the same issue and over different forums.

Thank you Mr Bean. I do appreciate you trying to assist. I created a 2nd topic here in order to add my screenshot. Which I guess I shouldve just replied to my own original post with it instead. My apologies mods! Im a newb here...as far as the different forum, I wondered if I should convert my files to something else to be more blu-ray friendly hence that posting there. I will try your theory on my issue and get back to you here. Thanks again

[Cornucopia]

Your referenced example: 23 hours on a 50GB bd disc.

The universal rule in encoding of anything using any format is:

 filesize = bitrate * running time

Plugging that in (assuming you filled it), 50GB = ? * 23hrs.
Or ? = 50GB / 23hrs = 400,000,000,000 bits / 82,800 sec = ~4.83Mbps.

So if you encoded your output to be less than or equal to that number of bitrate (video + audio), and it was the same duration, it would also (nearly) fill a disc.

FYI, there is a maximum bd bitrate of 40Mbps, but there is no actual listed minimum bitrate. However, there is a practical mimimal limit that is based on the vbv (video buffer verifier) so you don't get an underrun during playback, and there would obviously be a limit on the quality at such a low level.

Scott

[BabyDaddy]

Your referenced example: 23 hours on a 50GB bd disc.

The universal rule in encoding of anything using any format is:

 filesize = bitrate * running time

Plugging that in (assuming you filled it), 50GB = ? * 23hrs.
Or ? = 50GB / 23hrs = 400,000,000,000 bits / 82,800 sec = ~4.83Mbps.

So if you encoded your output to be less than or equal to that number of bitrate (video + audio), and it was the same duration, it would also (nearly) fill a disc.

FYI, there is a maximum bd bitrate of 40Mbps, but there is no actual listed minimum bitrate. However, there is a practical mimimal limit that is based on the vbv (video buffer verifier) so you don't get an underrun during playback, and there would obviously be a limit on the quality at such a low level.

Scott

Hi Scot...Texas cool. I was born there... so let's start from scratch. I have 65 files totaling 22 hours and 39 minutes = 80604 seconds Each one is 640X480 with an average total bitrate of a measly 900ish (see attachment of one file)....The reference I made was for this persons 1920X1080 with an average 4300 bitrate and 23 hours of material..... So mine should easily fit according to your calculations? The minimum my software will put on a BD is 720X480 so im guessing what is causing it to get enlarged beyond capacity is cause it is changing the files from 640X480 to 720X480???

[Cornucopia]

Stop right there!

This has already been mentioned to you: whatever the Source bitrate is has NO BEARING on the subsequent filesize. ONLY the final, encoded bitrate.

Your idea would only work if you were leaving your files as-is and burning onto disc as general data files (e.g. *.avi, *.mp4, *.mov, *.mkv, etc), in a "My Videos" folder or something.

Can all the players you use play these files natively (like your bdplayer)? If so, ok do that with Imgburn and you're done. Of course, you won't have any assurance of universally-compatible playability, nor of the full range features (menus, chapters, subs, alternate streams & playlists), but if you don't care about that, it's a wash.

If you DO care about any of that stuff, you must stop thinking of these as your finished product. They are merely your source assets. And they very likely may happen to be in formats that are not legit for a standards-compliant bluray disc. To make them compliant, they will need to be re-encoded. When they are, you need to be in charge of what that new encoded bitrate is set to. Notice I said bitrate, not resolution. Remember the formula!

To reiterate: standards-compliant.
640 x 480 is in no way compliant with the bluray standard. The options (in ntscland) are 720 x 480 for sd material, and 1280 x 720 or 1920/1440 x 1080 for hd material. That's it.
Your 640 stuff would have to be re-encoded at 720 x 480. In doing so, it has to start by decoding the 640 stuff back to an uncompressed displayable format (almost "from scratch"), then resize that to 720, then re-encode using settings that constrain it to being standards-compliant all around.

That is when that formula comes into play.

Are you setting the final encode settings to ~4.3Mbps? (Assuming 50GB disc)? And if you only have a 25GB disc, are you ensuring the settings are half that bitrate?

Look at your final-encoded files' (m2ts) bitrates in mediainfo. That should tell you.

Scott

[Brainiac]

Are those 2 discs someone else made authored or are they data discs?

[BabyDaddy]

Are those 2 discs someone else made authored or are they data discs?

Authored as they have a functional menu/chapter screens.... i believe what I need to find is a way to go from m2ts to m2ts with the ability to lower the bitrate

[Cornucopia]

If you already have compliant bd files (m2ts) but they are too high bitrate, one of the WORST things you could do is re-encode them again.

Every re-encoding loses quality (some exceptions when using lossless codecs)! These surely will.

Go back to your originals (for lack of a better term) and do it right once, using the proper intended bitrate from the start.

Scott

[DB83]

There is a well known saying which applies to all software. It is abbreviated to 'RTFM' or 'Read The Friggin' Manual'


And a quick glance of that shows in the following extract:


Video and Audio Settings
· Select the video recording format: if available for your selected disc format,
select the recording format of the video on your disc and its aspect ratio.
· Select the video encoding format and quality: if available for your selected disc
format, select a video encoding format and video quality for your disc from
the drop-downs. For quality, select the Smart Fit option if you want CyberLink
467
Creating Discs
PowerDirector to automatically adjust the bitrate to create the best quality
video file possible, which will fit the capacity of the disc you are using.


Now without testing the software I know not if it applies in your case. But you should see if it does.