Figures not found when building the book

[tkhurana]

I tried building the book but I keep getting these warnings

python3 export_book.py -ch 1 && pdflatex book.tex && bibtex book && pdflatex book.tex && pdflatex book.tex

! Package pdftex.def Error: File `../../img/intro/50-years-processor-trend.png'
not found: using draft setting.

See the pdftex.def package documentation for explanation.
Type H for immediate help.