Setting the proxy

Figure 6.1: Proxy settings dialog

Screencast in figure 6.1 shows the Rescaled to project size checked so you can still use plugins correctly and the original project size is kept. The Scale factor pull-down gives you available size options. Note the new media dimensions shown (partially covered). If the size is an odd number, 1 is added to make the dimensions both even numbers.

To go back to the original media permanently, simply set the Scale factor to Off or disable the Proxy by clicking on its toggle button. However, if you decide to reuse the proxies, those which have not been deleted from the Hard Disk (but have been removed from the project) will be used without re-rendering - this saves a lot of time. To completely remove the created proxies you will have to delete them manually from the Hard Disk. There is also a convenient Beep on done volume slider included so that you can work on other tasks until there is an audible notify of completion. The default volume is set to 0 for no audible notify.

A good choice for classic proxy settings with a 1080p source video is:

Scale Factor: 	1/4
File Format:	FFMPEG - mpeg
Video Preset:
Compression:	mpeg.mpeg
Bitrate:	2000000
Quality:	-1
Pixels:		yuv420p

If you get errors for some videos, such as those with strange variable bit rate or some types of files made on a smartphone, a usually reliable alternative is to change the following parameters:

File Format:	FFMPEG - mov
Video Preset:
Compression:	mov.mov

Or if you want small files with high image quality, a File Format of m2ts is optimal. For example a 1 GB file can be reduced to 50 MB with scale ${\frac{{1}}{{2}}}$.

If you get error messages when creating proxies, check the Video wrench settings. These usually default to values that are expected to work correctly for the File Format and codec you selected but they can be changed and may result in errors. If you get an error message of check_frame_rate failed followed by Error making proxy in the popup Errors window, do just that and check the Frame rate value by going to the Resources window, Media folder, and use the right mouse button for the Info option for the specific media in question. You can change the frame rate in this window to a more codec acceptable value. Different codecs may have different legal values.

A faster method of creating the proxy file outiside of CINELERRA-GG for users who have vaapi hardware acceleration capability on their graphics board is via a script. Speed up could potentially be 10 to 30 times faster depending on the parameter values you choose and the size of your video file. This script is included in the doc subdirectory as vaapi_proxy.sh for users not using an AppImage version and is shown below. You will have to tune it to your specific needs for the vaapi_device name (currently set to /dev/dri/renderr128), file type (currently set to h264 and mp4), and proxy size (now is 6). Once you have created the proxy file, you then start CINELERRA-GG, load the original un-proxied video, use the Settings pulldown and choose the Proxy settings options as you would normally, but because you already have created the existing proxy file with the correct name, it will be automatically loaded and will not have to create it. The filename of the proxy file must be in the same location as the original video and have the exact required naming conventions and scale factor.

#!/bin/bash
filename="$1"
fileout="${filename%.*}"
proxy="6"
# Hardware encode AMD
ffmpeg -threads 2 -hwaccel vaapi  -vaapi_device /dev/dri/renderD128 \
 -i  "$1" -c:v h264_vaapi -vf "format=nv12,hwupload,scale_vaapi=iw/'$proxy':ih/'$proxy'" \
 -vcodec h264_vaapi  -preset fast -c:a copy \
 -bf 0 -profile:v 66 "$fileout".proxy"$proxy"-mp4.mp4