Blackmagic Forum

FOR ABOUT 2 DAYS I HAVE BEEN HAVING A PROBLEM WITH MY DAVINCI RESOVE 17. BY INSERTING A FILE.MP4 OF ABOUT 3.20GB OF MY GOPRO, WITHOUT DOING ANY EDITING, WITHOUT INSERTING TEXTS, WITHOUT COLOR CORRECTION, WITHOUT ANY ACTION ON IT, AND EXPORTING IT IN H.264 PRESET (SAME FPS, SAME RESOLUTION) I GET A FILE OF 14.4GB.
SAME PROBLEM IF I TRY TO GENERATE OPTIMIZED FILE OR PROXY. I GET 20GB PROXY FOLDERS.
PROXY (OR OPTIMIZED FILE) AND EXPORT PROCESSES ARE FLUID BUT TERRIBLY SLOW (25 MINUTES FOR EACH).
I THINK I HAVE SOME WRONG IN SETTINGS IN THE PROJECT OR IN PREFERENCES BUT I CAN'T UNDERSTAND WHAT. APPARENTLY EVERYTHING IS THE SAME AS BEFORE.
I TRY TO INSERT SOME SCREEN SHOTS BELOW.
THANKS TO WHO WILL WANT TO HELP ME

Do you by any chance have Use Optimized Media selected in the Advanced tab of the Render Settings? I see you are using DNxHR HQ for your optimized media which could account for the large file size.

Charles Bennett wrote:Do you by any chance have Use Optimized Media selected in the Advanced tab of the Render Settings? I see you are using DNxHR HQ for your optimized media which could account for the large file size.

No........what kind of settings do you recommend? I use DNxHR HQ instead of DNxHR HQX to make work smoother. Am I wrong?

The formula here is very simple.

File Size = Bitrate x Duration.

Factors like resolution, frame rate, color corrections, effects, etc. have no impact on file size.

Jim Simon wrote:The formula here is very simple.

File Size = Bitrate x Duration.

Factors like resolution, frame rate, color corrections, effects, etc. have no impact on file size.

let me explain better ..... you are right! the original video has 60kbps, while the exported file has 280kbps ... I could solve it by setting the right bitrates, but it shouldn't give me back all those bitrates even if I keep on "best" ..... why does it?
I have the same problem on proxy or optimized media folders ..... compared to a 3GB file I get a 12GB proxy (or optimized media) folder ...... why? where am i wrong?

Your original file has a highly compressed GOP codec. Efficient for distribution on the internet or for recording on cheap media.
But difficult to work with on a computer and producing massive quality loss if used repeatedly. That's why codecs like DNxHX, Cineform or ProRes produce much bigger files, but preserve better quality and are easier on your hardware.

robertofarinelli73 wrote:where am i wrong?

Your expectations. The sizes are what they are. If you need more storage, get it and move on.

Jim Simon wrote:

robertofarinelli73 wrote:where am i wrong?

Your expectations. The sizes are what they are. If you need more storage, get it and move on.

So for you is it normal generate a proxy media bigger than original? ok..

Absolutely normal, I tried to explain why. But then, you can choose less resolution for proxies.

robertofarinelli73 wrote:generate a proxy media bigger than original?

If I'm shooting highly compressed H.264 and using Cineform for Optimized Media, absolutely.

The larger size (less compression) of the Cineform files is exactly what makes them soooo much easier to edit.