Differences

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--- ffmpeg [2023/08/27 20:51] – FFmpeg Explorer rjt
+++ ffmpeg [2025/07/22 01:10] (current) – [Editing] Rotation rjt
@@ Line 17: / Line 17: @@
 <code>ffmpeg -i [input].mp3 -c:a libvorbis -q:a 4 [output].ogg</code>
-Fuck-off those .WEBMs:
+Fuck-off those .WEBMs. ''copy'' here copies those streams, so they're no reencoded, it's just changing the container:
 <code>ffmpeg -i [input].webm -acodec copy -vcodec copy [output].mkv</code>
+A more compact way is to use ''-c'', which will copy over all streams (there's also ''-c:a'' (audio) ''-c:v'' (video) ''-c:s'' (subtitles)…:
+<code>ffmpeg -i [input].webm -c copy [output].mkv</code>
+So if you wanted to copy the video stream and just reencode/change the audio, for example:
+<code>ffmpeg -i [input].[ext] -acodec aac -vcodec copy [output].[ext]</code>
 === Multiple ===
@@ Line 31: / Line 39: @@
 <code>for i in *.mp3; do ffmpeg -i "$i" -c:a libvorbis -q:a 4 -map a "${i%.*}.ogg"; done</code>
-You can use the wildcard ''*'' in the file extension to, so if you've got a mix of .mkv and .mp4 files from Youtube you can do. say:
+You can use the wildcard ''*'' in the file extension too, so if you've got a mix of .mkv and .mp4 files from Youtube you can do. say:
 <code>for i in *.m*; do ffmpeg -i "$i" "${i%.*}.ogv"; done</code>
@@ Line 82: / Line 90: @@
 === Rotation ===
-Rotate 90°.
+Rotate 90°. This will reencode the video.
 <code>ffmpeg -i inputfile.ext -vf "transpose=1" outputfile.ext</code>
+To rotate -90° is ''transpose=2''.
+(The easiest, tidiest way to rotate a phone video is to just edit the metadata with [[exiftool]])
 === Trimming ===