Playback / Preview Lag Issue

Work offline using proxy media |

The drones use what's called long-GOP media. It's fantastic for the drone ... simplifies putting media on the card enormously, and is HEAVILY compressed. The problem is the load it puts on the CPU, RAM, and threads/cores subsystems for de-encoding and de-compressing. iMovie is a much simpler program, and puts far less load on the computer than PrPro. Not even comparable then.

Long-GOP means that one complete frame (an I frame) is captured every so many "frames", and in-between, a data set or matrice is recorded of the pixels that have changed since the last ... or next ... I frame. The in-between ones are called either p or b frames. Typical p/b frame grouping has been perhaps 9-15 frames between I frames.

Drones are running often 30 frames. The process ... the CPU calls up the first I frame ... decompresses, sends along, and records to RAM ... calls up the matrice for the pixel-changes, recalls the I frame from RAM, computes the next frame ... sends it along, stores to RAM ... calls up the next data set ... rinse & repeat.

Again, incredibly CPU/RAM intensive. Bad enough in 1080 media at 15 frames per I frame. Take it to 30 frames in 4k ... and remember, you just went up 4 times in the number of pixels to compute, from a bit over 2 million to well over 8 million per frame.

Hence ...the strong suggestion to at the least, use a full intraframe codec like Cineform for proxies. Intraframe codecs create a complete frame for every frame, so the CPU only has to decompress a frame, not any extra storing & computing. They're larger file-sizes per minute of media, but vastly easier on the CPU and other subsystems.

PrPro's new proxy setup is quite useful ... in the Media Browser, click to turn Ingestion on; click the wrench icons to change the ingestion settings, click the Ingestion tab, select "Create Proxies", and choose the Cineform ingestion preset ... it's about 1/4 the frame-size of your 4k media. Let PrPro sick Media Encoder on creating the proxies. Go have lunch ... or a meeting ... whatever.

Then in the Program manager, go to the options for including control icons in the Program manager control set, and drag the Proxy switch icon onto the Program manager. After that, a click on it & your using proxies, a click again & your using (and seeing) the original media. Slick & fast.

Neil

This is typical unfortunately. See this post:

Re: 4K Choppy playback - unable to edit

Although I'm a bit surprised you see the lag with 1080 footage as well. If you can share one of the original 1080p files from your Phantom I can have a look.