What command lines to use to convert from avi to mp4, but without destroying the framesize and making the file small as the original size or a little bit bigger, and same thing with mp4 to avi? Whenever I tried converting it became like 2 gb
Depending on how your original file was encoded, it may not be possible to keep the file size.
ffmpeg -i infile.avi youroutput.mp4
should keep frame sizes and rates intact while making an mp4 file.
ffmpeg -i infile.avi
will give you information about your input file - the frame size, codecs used, bitrate, etc.
You can also play with the
vcodec options when you generate your output. Remember also that mp4 and avi files can use various codecs and your mileage may vary according to which codec you pick.
I was very interested in converting avi files to mp4. Reading your post, I remembered this ffmpeg command:
ffmpeg -i input.avi -strict -2 output.mp4
-strict -2 is necessitated by the AAC codec which is experimental, but works (libaac), if you add those two parameters.
The output file is high-quality by default.
I have found this one:: Libav in Linux.
Installation: run command
sudo apt-get install libav-tools
Video conversion command:
Go to folder containing the video and run in terminal
avconv -i oldvideo.mp4 -ar 22050 convertedvideo.webm