[FFmpeg-user] Multiple xfade in one run

[Michael Koch]

Am 04.07.2022 um 18:46 schrieb Cecil Westerhof via ffmpeg-user:
> Paul B Mahol <onemda at gmail.com> writes:
>
>> On Mon, Jul 4, 2022 at 6:15 PM Cecil Westerhof via ffmpeg-user <
>> ffmpeg-user at ffmpeg.org> wrote:
>>
>>> Some time ago I was experimenting with xfade. I wanted to know how to
>>> use several in one run. Now I really needed it, so I did some digging
>>> and found this:
>>>       ffmpeg -y                  \
>>>        -i input0.mkv             \
>>>        -i input1.mkv             \
>>>        -i input2.mkv             \
>>>        -i input3.mkv             \
>>>        -i input4.mkv             \
>>>        -i input5.mkv             \
>>>        -i input6.mkv             \
>>>        -i input7.mkv             \
>>>        -i input8.mkv             \
>>>        -i input9.mkv             \
>>>        -vcodec libx264           \
>>>        -crf    26                \
>>>        -preset veryfast          \
>>>        -filter_complex "
>>>          [0:a][1:a] acrossfade=d=4[a1];
>>>          [0:v][1:v] xfade=transition=hlslice:
>>>                            duration=4:
>>>                            offset=308[v1];
>>>
>>>          [a1][2:a] acrossfade=d=4[a2];
>>>          [v1][2:v] xfade=transition=vertopen:
>>>                            duration=4:
>>>                            offset=357[v2];
>>>
>>>          [a2][3:a] acrossfade=d=4[a3];
>>>          [v2][3:v] xfade=transition=circlecrop:
>>>                            duration=4:
>>>                            offset=533[v3];
>>>
>>>          [a3][4:a] acrossfade=d=4[a4];
>>>          [v3][4:v] xfade=transition=rectcrop:
>>>                            duration=4:
>>>                            offset=1016[v4];
>>>
>>>          [a4][5:a] acrossfade=d=4[a5];
>>>          [v4][5:v] xfade=transition=slideup:
>>>                            duration=4:
>>>                            offset=1158[v5];
>>>
>>>          [a5][6:a] acrossfade=d=4[a6];
>>>          [v5][6:v] xfade=transition=wiperight:
>>>                            duration=4:
>>>                            offset=1473[v6];
>>>
>>>          [a6][7:a] acrossfade=d=4[a7];
>>>          [v6][7:v] xfade=transition=horzclose:
>>>                            duration=4:
>>>                            offset=1661[v7];
>>>
>>>          [a7][8:a] acrossfade=d=4[a8];
>>>          [v7][8:v] xfade=transition=diagbl:
>>>                            duration=4:
>>>                            offset=2082[v8];
>>>
>>>          [a8][9:a] acrossfade=d=4[a9];
>>>          [v8][9:v] xfade=transition=slideright:
>>>                            duration=4:
>>>                            offset=2211[v9]
>>>        "                         \
>>>        -map '[v9]' -map '[a9]'   \
>>>        output.mkv
>>>
>>> I hope there are better ways, because there are some problems with it.
>>> For example it needs a lot of memory. (24 GB)
>>>
>> Could use (a)movie filters and only use such filter when actually needed in
>> graph.
> I am concerning ffmpeg still a newbie. What do you mean by this?
>

I also didn't understand it.

Michael