Losslessly Extract Frames using Avisynth

[Jay123210599]

How do I use selectevery(48), selectevery(72), and imagewriter() to losslessly extract frames in AVIsynth?

[davexnet]

Here's a model you can use:

LwLibAvVideoSource("c:\path\source.mp4") # << this points to your source file
selectevery(72)          #  <<  extract every 72nd frame
ConvertToRGB24()
imagewriter("i:\media\images\",type="png")[   # << place PNG files in this folder

Download Lsmash/LWLibsource from here:
https://github.com/HomeOfAviSynthPlusEvolution/L-SMASH-Works/releases/download/1147.0....r1147.0.0.0.7z
Extract the files and put the 32 bit and 64 bit Lsmashsource.dll into the respective Avisynth Plus plugin directories

Open Vdub2 and drag the .avs script into the window. If the script is good the video will appear.
Select file/run video analysis pass to take a pass through the video and create the png files