vector - How I can make people collage in custom shape?

How can I make a similar-looking collage automatically with a vector output? I am open to any software, web application or plug-in.

Answer

The closest in Illustrator made with several Pattern Brush

• Make many pattern brushes with three figures as shown in the gif


• Press Alt and drag to the brush panel different figures to replace the brush end and start

• Make short horizontal segments inside the main shape where the figures will be, or make just one segment and after testing it with the brush, duplicate it several times. Short because each segment will have three figures.


• The segments must be in order, the lower down ahead and the rest successively back.

• Select all the segments and apply a brush pattern


• Select segments randomly and change the brush pattern

Result 100% vector. By the way, where's Waldo?