fragrantEmulsion wrote: Sun Dec 15, 2019 4:43 pm
If someone wants to tell me how to compress it without losing quality, I have FFMPEG and can operate a command line about as well as your average grandma can use the email.
3.6 GiB seems reasonable to me, but maybe it can be further compressed. Of course, it's not possible to compress it without losing quality, but the amount of quality lost will most likely be imperceptible.
Code: Select all
ffmpeg -i "$input" -map_metadata 0 -c:v libx264 -crf 18 -preset veryslow -c:a copy "$output"
-i "$input" :: The input stream. I used bash style variables to represent the input and output files.
-map_metadata 0 :: Preserves the metadata (like timestamps, etc.) of input stream 0, which is the only input stream in this example, and copies it to the output stream.
-c:v libx264 :: Selects the video codec, in this case, x264.
-crf 18 :: Constant Rate Factor. Variable bitrate mode which preserves quality. When the input is difficult to compress, the bitrate in increased. When the input is simple to compress, the bitrate is decreased. The scale for crf is logarithmic, and lower values increase quality at the expense of file size. 18 is considered to be nearly lossless, but won't end up bloating the file size.
-preset veryslow :: x264 has a number of presets, which determine the time / quality;size tradeoff. Here, there is a positive correlation between increased quality and decreased file size (unlike with x265...), so basically, the slower the preset, the better the results. veryslow is the slowest preset worth using.
-c:a copy :: Selects the audio codec. copy means to copy the bitstream of the audio track exactly from the input stream. This process does not re-encode the audio. I've found that the built-in aac encoder ffmpeg uses is utter trash and should not be used. If you really need to re-encode the audio, I'd recommend using Apple's aac encoder (which is kind of a pain in the ass to use on Windows). Since you used Mainconcept's aac encoder, which is packaged with Adobe Premiere, you could probably just use that, but choose a bitrate like 128 kb/s. I'm not familiar with that aac encoder flavor, so if it sounds warbly, then maybe you need to increase it, but no more than 192 kb/s.
Quoting myself:
