My new pi boots perfectly from Raspian buster but once the sd card is flashed with stretch os then only red light turns on. I need to install stretch os to work with opencv in C++ using geany editor. Kindly help.
The raspberrypi.org blog explained the need for Buster as follows: "The reason for this [new version of Rapbian] is that one of the important new features of Raspberry Pi 4 is that the open-source OpenGL video driver is now being used by default, and this was developed using the most recent version of Debian." That version of Debian is Buster.
I'd suggest you read the post at: https://www.raspberrypi.org/blog/buster-the-new-version-of-raspbian/
The point would be that there are no simple solutions to the issue such as new drivers or firmware. If you want to boot a Raspberry Pi 4 B, you must use Buster.
I don't think the needed bootcode and firmware is available in stretch.
I suggest you put the stretch based SD card in another Pi and do a