b0r3k / slideslive-dl

Manual & scripts for downloading Slideslive presentation into one file with video and synced slides.

slideslive-dl

• Use create-slide-video.py to download the slides and create video out of them. If it doesn't work, check the hardcoded parts of the urls.
• Use yt-dlp to download the videos from youtube. Links can be found in the source code of Slideslive webpage of given video. It can take also a link to youtube playlist (and use naming template then), download subtitles (even autogenerated) and embed them in the video file.
• Use ffmpeg to merge the two videos together, as in merge-videos.sh.

for f in slides/*.mp4;
do
	num="${f:7:2}"
	ffmpeg \
		-i videos/"$num"-video.mp4 \
		-i slides/"$num"-slides.mp4 \
		-filter_complex '[0:v]scale=w=1024:h=572,pad=1024:ih+572:x=0:y=571[int];[int][1:v]overlay=0:0[vid]' \
		-map "[vid]" \
		-map 0:a \
		-map 0:s? \
		-c:s copy \
		-c:v libx264 \
		-crf 23 \
		-preset veryfast \
		"$num"-final.mp4
done

The [0:v]scale=w=1024:h=572,pad=1024:ih+572:x=0:y=571[int] takes the video (v) at index 0, scales it to 1024x572 and pads to width 1024 and height ih (original) +572. The video is placed on coordinates x=0:y=571, so that the padding appears at the top.

[int][1:v]overlay=0:0[vid] then overlays the result with video (v) at index 1, placing it at coordinates 0:0.

-map 0:a takes the audio (a) from file at index 0, -map 0:s? takes all the subtitles (s) from the same file. -c:s copy copies some subtitle settings, -c:v libx264 uses this encoding for the video.