[FFmpeg-user] Msys2-Mingw64 OpenCV Build Error

Max Ashton max at halfapixel.net
Tue Sep 12 20:18:19 EEST 2017

Thanks for the response Mortiz,

Don't know how I missed that.

They were compiled with mingw64 so I'd say it's safe to assume opencv is 64 bit.


-----Original Message-----
From: ffmpeg-user [mailto:ffmpeg-user-bounces at ffmpeg.org] On Behalf Of Moritz Barsnick
Sent: 12 September 2017 15:30
To: FFmpeg user discussions <ffmpeg-user at ffmpeg.org>
Subject: Re: [FFmpeg-user] Msys2-Mingw64 OpenCV Build Error

On Tue, Sep 12, 2017 at 12:52:57 +0000, Max Ashton wrote:

> Looking though the opencv 3.2 documentation it appears that cvRound 
> has been dropped? As I find it in the 2.4 documentation but not the 
> 3.2.

I can find it:

> gcc -Wl,--nxcompat,--dynamicbase -Wl,--high-entropy-va -Wl,--as-needed 
> -Wl,--image-base,0x140000000 -o /tmp/ffconf.INsGNY2h/test.exe 
> /tmp/ffconf.INsGNY2h/test.o -lopencv_core -lopencv_imgproc -lmp3lame 
> -LC:/msys64/mingw64/lib -lfreetype -LC:/msys64/mingw64/lib -lfdk-aac 
> -LC:/msys64/mingw64/lib -lass -lm -llzma -lbz2 -lz -lpsapi -ladvapi32 
> -lshell32 -lole32
> C:/msys64/tmp/ffconf.INsGNY2h/test.o:test.c:(.text+0x5fc): undefined reference to `cvRound'
> C:/msys64/tmp/ffconf.INsGNY2h/test.o:test.c:(.text+0x5fc): relocation truncated to fit: R_X86_64_PC32 against undefined symbol `cvRound'

I don't know much about MinGW(64) and MSys, but on Linux, this would have looked like a 32 vs. 64 bit compilation/linking issue. Do the libs you have downloaded with pacman correspond to the target you are compiling your ffmpeg for? (Yes, I do see there's a "64" everywhere in the paths - just wondering.)

ffmpeg-user mailing list
ffmpeg-user at ffmpeg.org

To unsubscribe, visit link above, or email ffmpeg-user-request at ffmpeg.org with subject "unsubscribe".

More information about the ffmpeg-user mailing list