This will make it a lot more convenient when we need to call ffmpeg, we dont need to type the full path, and workign in the directory where our video files are will make the process shorter and easier to keep track of. This is just one of the many use cases for VMAF.īefore we start, if you have not already done so, I would heavily encourage adding ffmpeg.exe to your PATH (search for "Edit the system" > Advanced > Env var > Path > add path to ffmpeg.exe).
The way I usually use VMAF is to test the impacts of different parameters, resolutions, frame rates etc under certain bitrate constraints for instance. I would consider anything above 80 to be quite good, and above 90 to very close perfect/indistinguishable from the ref. We consider a score of 20 to be very bad, and a score of 100 to be excellent (flawless).
#How to use ffmpeg windows 1080p
For our model, its predicting quality of the video on a 1080p display in a "living room environment", and presuming that the persons viewing distance is 3x the height of the screen (25cm monitor/TV height = 75cm viewing distance). The VMAF score will be using the model we've chosen to provides us a score, so what it's actually telling us will change a bit depending on the model. This is the video file that we've compressed/modified, and we're looking to score this file against the reference file (1). It dosent have to be perfect, but this is what the model will be comparing against. This is the file we will be comparing against, and will serve as our "flawless"/perfect video. But first, we need to be familiar with a couple of different concepts.
We'll start with the most basic from of analyzing a video file. There is also other cute bonus stuff we can do this way, we'll get to those parts later. Might as well cut it down, and have ffmpeg do everything for us. The reason is that VMAF only works with YUV format, and if you're planning to test a bunch of different videos, then its pretty likely that you will need to use ffmpeg to convert stuff regardless. Now, you might be wondering, why would we bother with this when we could just use the tool that Netflix released (vmafossexec.exe or vmaf.exe)? Cant we just use this instead? (now replaced by vmaf) I prefer placing the models in a short path, for instance in a subfolder of where ffmpeg is located, as this might make it a bit easier to to reference (which we will need to do). The models are located in the "models" folder, make sure you grab all of them, to be sure. I will using and referring to the default model vmaf_v0.6.1.json.
#How to use ffmpeg windows windows
If you're on windows like me, and dont feel like compiling, you can grab this link (needs 7zip), courtesy of "Gyan":ĭepending on the scenario you want to test you can choose different models. The despair mostly comes later though, once you have it up and running.įor this we will need a couple of different things. Unfortunately, it's not entirely straightforward, especially on windows. VMAF is an incredibly useful tool to do video analysis and comparisons. NOTE: With the release of VMAF 2.0, the pkl models have now been swapped for the json models.
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