Build voxl-uvc-server with voxl-cross

Philemon Benner

@Eric-Katzfey Not really it's used in the tutorial for building voxl-tflite-server from source. I basically want to replace libmodal pipe input with libuvc in the tflite-server, using parts of the voxl-uvc-server. Is it possible to build tflite-server in the voxl-emulator without changing anything?

Eric Katzfey

@Philemon-Benner That's not something we have tried. But I can't imagine that it would be too difficult to get voxl-tflite-server building in voxl-emulator. Any reason that you can't leave voxl-uvc-server and voxl-tflite-server as separate processes communicating via MPA?

Philemon Benner

@Eric-Katzfey yeah i want to have in/output in one executable(tflite-server). So that i have better control and exception handling for these. I will try and integrate tflite-server in voxl-emulator.

Philemon Benner

@Eric-Katzfey so tried compiling tflite-server in voxl-emulator, but when building it complains about everything. So i tried just integrating libuvc in tflite-server in voxl-cross. Installation works fine. But when building it's complaining about libuvc being incompatible. Is it because i'm trying to build it with arm64 instead of the way voxl-emulator does in arm32 ?(mentioned in the docs https://gitlab.com/voxl-public/utilities/voxl-docker) What would i have to change to build in voxl-cross?

Package Installation:

voxl-cross:~$ ./install_build_deps.sh dev
using dev IPK repo
Downloading http://voxl-packages.modalai.com/dev/Packages.gz.
Updated source 'dev'.
installing: 
libmodal-pipe libmodal-json voxl-opencv voxl-tflite libuvc
Installing libmodal-pipe (2.1.5) on root.
Downloading http://voxl-packages.modalai.com/dev/libmodal-pipe_2.1.5_202203110042.ipk.
Configuring libmodal-pipe.
Installing libmodal-json (0.4.0) on root.
Downloading http://voxl-packages.modalai.com/dev/libmodal-json_0.4.0_202203110044.ipk.
Configuring libmodal-json.
Installing voxl-opencv (4.5.5) on root.
Downloading http://voxl-packages.modalai.com/dev/voxl-opencv_4.5.5_202202082046.ipk.
Configuring voxl-opencv.
Installing voxl-tflite (2.2.3) on root.
Downloading http://voxl-packages.modalai.com/dev/voxl-tflite_2.2.3-1_202201270503.ipk.
Configuring voxl-tflite.

Done installing voxl-tflite

Installing libuvc (1.0.3) on root.
Downloading http://voxl-packages.modalai.com/dev/libuvc_1.0.3_202201232120.ipk.
Configuring libuvc.
/home/root

Done installing libuvc

Done installing dependencies

Build Output:

voxl-cross:~$ ./build.sh 820
-- The C compiler identification is GNU 4.9.3
-- The CXX compiler identification is GNU 4.9.3
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: /usr/bin/aarch64-linux-gnu-gcc-4.9 - skipped
-- Detecting C compile features
-- Detecting C compile features - done
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /usr/bin/aarch64-linux-gnu-g++-4.9 - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Configuring done
-- Generating done
-- Build files have been written to: /home/root/build64
[ 50%] Building CXX object src/CMakeFiles/voxl-tflite-server.dir/main.cpp.o
[ 50%] Building CXX object src/CMakeFiles/voxl-tflite-server.dir/inference_helper.cpp.o
[ 75%] Building C object src/CMakeFiles/voxl-tflite-server.dir/resize.c.o
In file included from /usr/aarch64-linux-gnu-2.23/include/features.h:367:0,
                 from /usr/aarch64-linux-gnu-2.23/include/stdio.h:27,
                 from /home/root/src/resize.c:1:
/usr/aarch64-linux-gnu-2.23/include/bits/stdlib.h:64:8: warning: no previous declaration for 'ptsname_r' [-Wmissing-declarations]
 __NTH (ptsname_r (int __fd, char *__buf, size_t __buflen))
        ^
/usr/aarch64-linux-gnu-2.23/include/sys/cdefs.h:57:59: note: in definition of macro '__NTH'
 #  define __NTH(fct) __attribute__ ((__nothrow__ __LEAF)) fct
                                                           ^
[100%] Linking CXX executable voxl-tflite-server
/usr/lib/gcc-cross/aarch64-linux-gnu/4.9/../../../../aarch64-linux-gnu/bin/ld: skipping incompatible /usr/lib/../lib/libuvc.so when searching for -luvc
/usr/lib/gcc-cross/aarch64-linux-gnu/4.9/../../../../aarch64-linux-gnu/bin/ld: skipping incompatible /usr/lib/../lib/libuvc.a when searching for -luvc
/usr/lib/gcc-cross/aarch64-linux-gnu/4.9/../../../../aarch64-linux-gnu/bin/ld: skipping incompatible //usr/lib/libuvc.so when searching for -luvc
/usr/lib/gcc-cross/aarch64-linux-gnu/4.9/../../../../aarch64-linux-gnu/bin/ld: skipping incompatible //usr/lib/libuvc.a when searching for -luvc
/usr/lib/gcc-cross/aarch64-linux-gnu/4.9/../../../../aarch64-linux-gnu/bin/ld: cannot find -luvc
collect2: error: ld returned 1 exit status
src/CMakeFiles/voxl-tflite-server.dir/build.make:128: recipe for target 'src/voxl-tflite-server' failed
make[2]: *** [src/voxl-tflite-server] Error 1
CMakeFiles/Makefile2:97: recipe for target 'src/CMakeFiles/voxl-tflite-server.dir/all' failed
make[1]: *** [src/CMakeFiles/voxl-tflite-server.dir/all] Error 2
Makefile:135: recipe for target 'all' failed
make: *** [all] Error 2

Eric Katzfey

@Philemon-Benner You can build a 64 bit version of libuvc with the dev branch on our libuvc project: https://gitlab.com/voxl-public/third-party/libuvc/-/tree/dev. Use the instructions to build for qrb5165 and it will produce 64 bit versions.

Philemon Benner

@Eric-Katzfey Do i have to use the qrb-emulator for that or can i do it in voxl-emulator?

Philemon Benner

@Eric-Katzfey tried that getting the following errors:

/usr/lib/gcc-cross/aarch64-linux-gnu/4.9/../../../../aarch64-linux-gnu/bin/ld: warning: libusb-1.0.so.0, needed by /usr/lib/../lib/libuvc.so, not found (try using -rpath or -rpath-link)
/usr/lib/gcc-cross/aarch64-linux-gnu/4.9/../../../../aarch64-linux-gnu/bin/ld: warning: libjpeg.so.8, needed by /usr/lib/../lib/libuvc.so, not found (try using -rpath or -rpath-link)

when trying to build in tflite-server. I Built libuvc in qr-emulator. Installed the deb file in tflite-server without errors.

Eric Katzfey

@Philemon-Benner In voxl-cross?

Philemon Benner

yeah i think i need to install libusb and libjpeg but wich exact verisions?

Eric Katzfey

@Philemon-Benner Now you are starting to see the problem with voxl-cross. It is a much faster way to compile code but for projects that have more complex dependencies it can be a real pain to get them setup. That is why some projects use voxl-emulator. It's much easier to setup dependencies there.

Philemon Benner

@Eric-Katzfey yeah i see

Philemon Benner

Ok so i finally got it working if someone ever needs it, with installing:

sudo apt-get update
sudo apt-get install libusb-1.0-0:arm64
sudo apt-get install libjpeg-turbo8:arm64

For other third part libraries add the :arm64 architecture when building with 820, because in voxl-cross it will install amd64 by default. Still wondering what 820 exactly is

Thanks @Eric-Katzfey for the suggestion on the 64-Bit deb package.

Eric Katzfey

@Philemon-Benner 820 refers to the Qualcomm Snapdragon 820 SoC that is the heart of the Voxl product. https://www.qualcomm.com/products/snapdragon-820-mobile-platform

Philemon Benner

@Eric-Katzfey Ok i ran into the next problem when trying to run tflite-server.

voxl:~/tflite-server(master)$ voxl-tflite-server -t -d
voxl-tflite-server: error while loading shared libraries: libuvc.so.0: cannot open shared object file: No such file or directory

Tried to install the 64-Bit BInary file but it's throwing the following error:

voxl:~/tflite-server(master)$ opkg install libuvc_1.0.3.deb
Collected errors:
 * pkg_extract_control_file_to_stream: Failed to extract control.tar.gz from package 'libuvc_1.0.3.deb'.
 * pkg_init_from_file: Failed to extract control file from libuvc_1.0.3.deb.

So i tried using this from ur code:

voxl:~/tflite-server(master)$ dpkg -i --force-downgrade --force-depends /data/libuvc_1.0.3.deb
-bash: dpkg: command not found

Normal installation from modalai dev branch still throws the same error after installation:

opkg install libuvc

Any suggestions?

Eric Katzfey

@Philemon-Benner You can only install a Debian package with dpkg, which we have on our qrb5165 based platform, but not on our 820 based Voxl. That only has opkg and you need ipk packages, not debian packages.

Philemon Benner

This post is deleted!

Philemon Benner

@Eric-Katzfey Ok so i got working now but i am having issues with the Format. So when using UVC Server i got the response that frame format succeed on index 2. In your voxl-uvc-server code at the Top Frame Format 2 should be:

static enum uvc_frame_format supported_frame_format[NUM_SUPPORTED_FRAME_FORMATS] =
     {UVC_FRAME_FORMAT_YUYV, UVC_FRAME_FORMAT_UYVY, UVC_FRAME_FORMAT_NV12};
static int supported_mpa_frame_format[NUM_SUPPORTED_FRAME_FORMATS] =
     {IMAGE_FORMAT_YUV422, IMAGE_FORMAT_YUV422_UYVY, IMAGE_FORMAT_NV12};

supported mpa_frame_format = IMAGE_FORMAT_NV12 = 1 // regarding to https://gitlab.com/voxl-public/modal-pipe-architecture/libmodal_pipe/-/blob/master/library/include/modal_pipe_interfaces.h
frame_format supported_frame_format = FRAME_FORMAT_NV12 = 17

But still i am getting a real weird looking image(wrong colors) voxl-portal. Are the Configurations right that i use, or is it something else? Can't upload any pictures rn becuase of some server error.

Philemon Benner

Ok so apparrently the Frame format stuff is alright when directly writing the frame from the callback to the pipe server. I think it's some fault in the code. One Question why are you using c instead of c++? I'm not an expert at c/c++ stuff but i was told that c++ is generally faster than c.

Philemon Benner

Ok i got it working now.
@Eric-Katzfey i don't know anything of the qrb thing but in the dev libuvc branch, if you build it in 64-Bit version, why is it then copied in the 32-Bit dir in your make_package.sh L:87-89:

sudo mkdir -p $DATA_DIR/usr/lib
sudo cp build/libuvc.so.0.0.6 $DATA_DIR/usr/lib
sudo cp build/libuvc.a $DATA_DIR/usr/lib

an if else would be nice.

sudo mkdir -p $DATA_DIR/usr/lib64
sudo cp build/libuvc.so.0.0.6 $DATA_DIR/usr/lib64
sudo cp build/libuvc.a $DATA_DIR/usr/lib64

also had to add:

sudo cp /usr/lib/aarch64-linux-gnu/libjpeg.so.8 $DATA_DIR/usr/lib64
sudo cp /usr/lib/aarch64-linux-gnu/libjpeg.so.8.1.2 $DATA_DIR/usr/lib64

to make it work on voxl because voxl doesn't have it installed by default.

Eric Katzfey

@Philemon-Benner I'm not sure where those lines of code came from. The file make_package.sh in the dev branch has this for lines 87-89:

	sudo mkdir -p $DATA_DIR/usr/lib
	sudo cp $BUILD_TYPE/libuvc.so.0.0.6 $DATA_DIR/usr/lib
	sudo cp $BUILD_TYPE/libuvc.a $DATA_DIR/usr/lib

Where BUILD_TYPE will be either build32 or build64. It looks like you are taking from lines 65-66 on the master branch.