Slideshow

[mlum]

How do you do a slide show to post on Facebook and/or Instagram?

[eumagga0x2a]

I have no idea about the particular requirements of the above platforms, but in general, you load a picture (JPEG, PNG or BMP) in Avidemux, select a lossless encoder (e.g. "Ut Video") or H.264 with "Mezzanine" preset, resize/zoom it using one of the matching filters (i.e. "resize" or "zoom") in Avidemux to match a usual default resolution (e.g. 1280x720, 1920x1080 etc.), apply "still image" filter to repeat it for the period of time you need and export it as MKV.

Repeat the above steps with all pictures, until you get a set of videos, then load the first one in Avidemux and append all the others in the desired order and create transitions (have a look at "Fade through" filter) and fade-in / fade-out if wanted.

Add an external audio track from a 16-bit WAV, "raw" (ADTS encapsulated) AAC, MP3, AC3, EAC3 or DTS file and re-encode the video using the final codec you need (H.264, VP9, I don't know whether these platforms accept HEVC) with the compression settings you like. If audio is 16-bit WAV, you should probably compress it using preferably an AAC encoder – lav (libavcodec), FDK or FAAC – for export as MP4 or Opus if you export as WEBM / MKV. For Opus, the sampling rate must be 48kHz.