FCP X Blu Ray Rendering Problem

[smudger9]

I'm attempting to produce Blu Ray files of my completed Fanedits, but I'm having a major issue with the output quality.

I've tried rendering from both FCP and Compressor, but when I do so, the final file size is around 13GB (for a 120 min movie), which is about half what it should be, and the picture quality when burned to disc is much poorer than the 1080 m4a file of the same movie.

I've checked the settings of the project and its 1080.

What am I doing wrong???

 

[DSM2337]

If you can provide a screen cap of Compressor Video settings then I'll compare to my settings when I produce something.

 

[smudger9]

 

[ThrowgnCpr]

I'm not a FCP user, but I notice a few things from that screenshot. First, you have the bitrate set to automatic. I'm not sure what is going on in that automatic process to limit it to that file size, but nowhere on that screen can you set the media output format (e.g., BD25 vs. BD50). That tells me that you need to figure out the best bitrate manually and enter the values. Try this bitrate calculator:

http://dvd-hq.info/bitrate_calculator.php

If that seems too complicated, just check the bitrate of the file you got last time (the 13GB one). A bit under double that should work for your bluray.

 

[thecuddlyninja]

I'm not a FCP user either but doesn't it say in the upper right that the file will be around 21gb? Those are definitely the settings yielding the smaller file, right?

 

[ThrowgnCpr]

I'm not a FCP user either but doesn't it say in the upper right that the file will be around 21gb? Those are definitely the settings yielding the smaller file, right?

I saw that, but it must be messing up the predicted output size somehow. A 120 minute movie should fit on a BD25 at a bitrate of ~24000 kbps. The screenshot says it is encoding to an average of 19000 kbps, which should be larger than 13GB. Did you check the media properties of the 13GB file to see if it is actually encoded at 19 mbps?

 

[DSM2337]

Afraid I can't really add anything more to this. I tend to go for the automatic settings too, it does appear to me that as a default it will aim for a target estimated size of around 21G and adjust the average bit rate to achieve that. If you increase the average bit rate so the estimated size goes over 25G then you get a warning, and have to specify dual layer in the BD main screen.

Why you are getting a much smaller size and loss of quality, I don't know I'm afraid, everything looks okay. Sorry, not much help.

 

[smudger9]

I saw that, but it must be messing up the predicted output size somehow. A 120 minute movie should fit on a BD25 at a bitrate of ~24000 kbps. The screenshot says it is encoding to an average of 19000 kbps, which should be larger than 13GB. Did you check the media properties of the 13GB file to see if it is actually encoded at 19 mbps?

Not sure what compressor is doing. I set 24000 and it produced a 16GB file! Go figure.

 

[ThrowgnCpr]

Not sure what compressor is doing. I set 24000 and it produced a 16GB file! Go figure.

can you please report the specs of your output file? video codec, video bitrate, audio bitrate. Not what you set it to, but what actually came out. That might shed some light on this

 

[smudger9]

The output files have no "extra info", so I don't know what the bitrate is.

Below is the file info for the Video and audio
I set the target bitrate to the maximum I could - 30Mbps and it still only gave me a combined file size of 22GB (for a 140 minute movie). Very Strange.

 

[ThrowgnCpr]

The output files have no "extra info", so I don't know what the bitrate is.

Yes they do, you just have to know how to read the information On windows there is a program called mediainfo that displays all of the specifications for any media file. I'm not sure if there is a Mac analog.

EDIT: Apparently there is a Mac version: https://mediaarea.net/en-us/MediaInfo/Download/Mac_OS

 

[smudger9]

This is for a file 1 minute long. Predicted size on compressor was 220MB

This is what it threw out

 

[ThrowgnCpr]

there is no average or minimum bitrate reported. maybe because the video is only 1 minute long. Did you already delete your other renders?

 

[smudger9]

Yes, needed to clear disc space. I'll render again and have a look. I'll post back tomorrow.

 

[smudger9]

I've been doing a little testing with compressor today, using a 15 minute clip.

I can't get any software to read the bitrate of the Bluray exports, so I've been fiddling around with DVD exports using different Bitrates. The file data is below.

As you can see, at 2Mbps, the selected bitrate is roughly what I'm getting. However, as the bitrate rises above 2, I'm progressively losing the bitrate, with 7Mbps producing only half what I select.

However, if I export other file types like .mov or ProRes I get pretty much the bitrate I select. There is some loss, but its nowhere near as significant.

I've altered all I can think of both in Final Cut Pro and in Compressor, but it makes no difference. In FCP the open movie is in its original media form, with best quality selected. The movie project is in ProRes format with 1080 screen size selected.

Here are the compressor settings.

I have no idea why I'm losing DVD and Bluray bitrate. Any ideas??