--sout-file-append problems

[Idsa]

I wand to append stream to existing file. I use the following command line:

vlc fake:// --fake-file image2.jpg --sout-file-append --sout "#transcode{vcodec=mp4v,vb=4000}:std{access=file,mux=mp4,dst=1.mpg}"

During the recording file size is growing... but when I stop the recording and try to open the file I do not see appended video. What are the criterions for sout-file-append option using? Should the size of the picture be the same? Should be used the same codec? Or may something else?

[Rémi Denis-Courmont]

The MPEG4 file format is not appendable.