![]() ![]() So, a reasonably complete command would look like: ffmpeg -i input.mov -vf scale=720x406,setdar=16:9 -preset slow -profile:v main -crf 20 output.mov You may want to put additional commands for the codec and so on, eg -c:v libx264 to use the x264 mp4 encoder, and something like -crf 20 to set the constant rate factor to 20 (usually a pretty good compromise between size and quality). Filters can be quite complex, but in the most simple usage they take the form effect=parameter,nexteffect=anotherparameter, and they get processed in the order you write them. What I'm doing with the -vf command and the x=y,z=a expressions that follow is creating a chain of filters. So if you want to stretch the movie anamorphically to a new aspect ratio you need to manually set the pixel aspect ratio, called the SAR for "Sample Aspect Ratio", thus for square pixels use: ffmpeg -i input.mov -vf scale=720x406,setsar=1:1 output.mp4Īlternatively you can set the display aspect ratio to whatever you want, thus: ffmpeg -i input.mov -vf scale=720x406,setdar=16:9 output.mp4 Will create a movie with the required pixel dimensions, but if you look at the output you'll find that it adds information into the metadata so that it will play back at the same aspect ratio as the original, by using non-square pixels. ![]() ffmpeg -i input.mov -vf scale=720x406 output.mov ![]() Using the scale filter will do it, but there is a bit more to it. ![]()
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