I am trying to resize a video from 1920x1800
to 1280x720
for phone viewing.
This is the command I used:
avconv -i input.mkv \
-map 0:v -map 0:a:1 -map 0:s:0 \ # map video, 2nd audio stream, and subtitles
-s 1280x720 \ # resize
-c:a copy -c:s copy \ # copy audio and subtitles
output.mkv`
The output is indeed the correct resolution, but it suffers from artifacts.
Input:
Output:
Output detail: