How to Construct RTSP Stream from Axis Camera Data Using VdoStream API?

[bachtran02]

Hi! I'm trying to create an RTSP stream for an Axis camera on the cloud to enable remote access. I believe this might be possible using the Native SDK, specifically the VdoStream API. According to the documentation, VdoStream allows access to VdoFrame, which in turn provides VdoChunk containing a pointer to some data. Is there a way to construct an RTSP stream from this data?

I'm still quite new to the documentation, so any help or suggestions would be greatly appreciated!

Thank you!

[github-actions[bot]]

This automatically generated reply acts as a friendly reminder.

Answers to your questions will most often come from the community, from developers like yourself. You will, from time to time, find that Axis employees answers some of the questions, but this is not a guarantee. Think of the discussion forum as a complement to other support channels, not a replacement to any of them.

If your question remains unanswered for a period of time, please revisit it to see whether it can be improved by following the guidelines listed in Axis support guidelines.

[vivekatoffice]

Hi @bachtran02,
Check out if this can be used for your requirements.
Application for Amazon Kinesis Video Streams

If you are looking for the Axis RTSP stream URL, check this link:
RTSP Options

Please let me know why you need to create an RTSP stream using an ACAP application instead of using the existing RTSP URL from the Axis device.

[bachtran02]

Hi @Cacsjep

I tried following the repo that you sent and this is what I have right now.

Makefile

TARGET = acap_app
OBJECTS = $(wildcard *.cpp)

PKGS = gio-2.0 gio-unix-2.0 vdostream

CXXFLAGS += -Os -pipe -std=c++11

CXXFLAGS += $(shell PKG_CONFIG_PATH=$(PKG_CONFIG_PATH) pkg-config --cflags-only-I $(PKGS))
LDLIBS += $(shell PKG_CONFIG_PATH=$(PKG_CONFIG_PATH) pkg-config --libs $(PKGS))

CXXFLAGS += -I${FF_BUILD_DIR}/include/
LDFLAGS = -L./lib -Wl,--no-as-needed,-rpath,'$$ORIGIN/lib'

LDLIBS += -lavcodec -lavdevice -lavfilter -lavfilter -lavformat -lpostproc -lswresample -lswscale

all: $(TARGET)

$(TARGET): $(OBJECTS)
	$(CXX) $(CXXFLAGS) $(LDFLAGS) $(LDLIBS) $^ -o $@ ;

clean:
	rm -f $(PROGS) *.o core *.eap

Dockerfile

ARG ARCH=aarch64
ARG REPO=axisecp
ARG SDK=acap-native-sdk
ARG UBUNTU_VERSION=22.04
ARG VERSION=1.3

FROM ${REPO}/${SDK}:${VERSION}-${ARCH}-ubuntu${UBUNTU_VERSION}

# Set general arguments
ARG ARCH
ARG VERSION
RUN echo "Architecture is: ${ARCH}"
ARG SDK_LIB_PATH_BASE=/opt/axis/acapsdk/sysroots/${ARCH}/usr
RUN echo "SDK library path base is: ${SDK_LIB_PATH_BASE}"

#-------------------------------------------------------------------------------
# Prepare build environment
#-------------------------------------------------------------------------------

RUN apt-get update && \
    DEBIAN_FRONTEND=noninteractive apt-get install -y -f --no-install-recommends \
    wget \
    yasm \
    nasm \
    git \
    build-essential 

RUN apt-get clean && rm -rf /var/lib/apt/lists/*

#-------------------------------------------------------------------------------
# libav build
#-------------------------------------------------------------------------------

ARG FF_BUILD_DIR=/opt/build
ARG FFMPEG_VERSION=n5.1.2
ARG CROSS_PREFIX=aarch64-linux-gnu-

RUN mkdir -p ${FF_BUILD_DIR} && \
    echo "Building FFmpeg" && \
    git clone https://github.com/FFmpeg/FFmpeg.git ${FF_BUILD_DIR}/ffmpeg && \
    cd ${FF_BUILD_DIR}/ffmpeg && \
    git checkout ${FFMPEG_VERSION} && \
    ./configure \
      --arch=${ARCH} \
      --target-os=linux \
      --cross-prefix=${CROSS_PREFIX} \
      --enable-cross-compile \
      --prefix=${FF_BUILD_DIR} \
      --disable-everything \
      --disable-programs \
      --enable-avfilter \
      --enable-avformat \
      --enable-avcodec \
      --enable-avutil \
      --enable-parser=h264,mjpeg,hevc,aac,mp3 \
      --enable-bsf=h264_metadata,h264_mp4toannexb,hevc_metadata,hevc_mp4toannexb,aac_adtstoasc \
      --enable-protocol=file,rtmp,rtmpt,rtp,data,tcp,pipe,hls \
      --enable-encoder=h264,mjpeg,hevc,aac,mp3 \
      --enable-decoder=h264,mjpeg,hevc,aac,mp3 \
      --enable-muxer=flv,h264,mjpeg,hevc,mov,mpegts,aac,mp3 \
      --enable-gpl \
      --enable-small \
      --disable-doc \
      --enable-shared && \
    make && make install;

WORKDIR /opt/app
COPY ./app .

RUN mkdir lib && \
    cp -a ${FF_BUILD_DIR}/lib/. ./lib;

RUN . /opt/axis/acapsdk/environment-setup* && \
    acap-build ./

However, it seems like I'm not linking the .so files correctly as I am getting this error message

/usr/lib/gcc-cross/aarch64-linux-gnu/11/../../../../aarch64-linux-gnu/bin/ld: ./lib/libavformat.so: undefined reference to `av_opt_set_int@LIBAVUTIL_57'

I wonder if you could help me out a little bit on this!

[Cacsjep]

What Happens If you set LDFLAGS in makefile to FF_BUILD_DIR

[bachtran02]

This is the code I tried running.

LDFLAGS = -L${FF_BUILD_DIR}/lib -Wl,--no-as-needed,-rpath,'$$ORIGIN/lib'

And I got this error

aarch64-linux-gnu-g++  -mcpu=cortex-a53 -march=armv8-a+crc+crypto -fstack-protector-strong  -O2 -D_FORTIFY_SOURCE=2 
-Wformat -Wformat-security -Werror=format-security --sysroot=/opt/axis/acapsdk/sysroots/aarch64 -L/opt/axis/acapsdk/sysroots/aarch64/usr/lib 
-O2 -pipe -g -feliminate-unused-debug-types  -Os -pipe -std=c++11 -I/opt/axis/acapsdk/sysroots/aarch64/usr/include/vdo 
-I/opt/axis/acapsdk/sysroots/aarch64/usr/include/gio-unix-2.0 -I/opt/axis/acapsdk/sysroots/aarch64/usr/include/glib-2.0 
-I/opt/axis/acapsdk/sysroots/aarch64/usr/lib/glib-2.0/include -I/opt/build/include/ 
-L/opt/build/lib -Wl,--no-as-needed,-rpath,'$ORIGIN/lib' -lvdostream -lgio-2.0 -lgobject-2.0 -lglib-2.0 
-lsystemd -lavcodec -lavdevice -lavfilter -lavfilter -lavformat -lpostproc -lswresample -lswscale acap_app.cpp -o acap_app ;

/usr/lib/gcc-cross/aarch64-linux-gnu/11/../../../../aarch64-linux-gnu/bin/ld: warning: libavutil.so.57, needed by /opt/build/lib/libavcodec.so, not found (try using -rpath or -rpath-link)
/usr/lib/gcc-cross/aarch64-linux-gnu/11/../../../../aarch64-linux-gnu/bin/ld: /opt/build/lib/libavformat.so: undefined reference to `av_opt_set_int@LIBAVUTIL_57'
...

Interestingly, if I set only LDFLAGS to this

LDFLAGS = -L${FF_BUILD_DIR}/lib

then it compiles fine but cannot find ffmpeg function called in the program

/usr/lib/gcc-cross/aarch64-linux-gnu/11/../../../../aarch64-linux-gnu/bin/ld: /opt/app/acap_app.cpp:24: undefined reference to `avformat_alloc_output_context2'

Right now I'm just testing out if I can include both ACAP SDK functions and FFMPEG functions correctly so this is my dummy main function

extern "C" {
    #include <libavformat/avformat.h>
    #include <libavcodec/avcodec.h>
}

#include "vdo-map.h"

#include <glib.h>
#include <glib/gstdio.h>
#include <signal.h>
#include <stdlib.h>
#include <syslog.h>
#include <iostream>

int main(int argc, char* argv[]) {
    openlog("acap_app", LOG_PID | LOG_CONS, LOG_USER);
    syslog(LOG_INFO, "Running test ACAP app");

    const char* RTSP_SERVER = "rtsp://<server-ip>:<port>/<path>";

    VdoMap* settings = vdo_map_new();

    AVFormatContext* ofmt_ctx = nullptr;
     avformat_alloc_output_context2(&ofmt_ctx, nullptr, "rtsp", RTSP_SERVER);
    if (!ofmt_ctx) {
        std::cout << "Could not create output context." << std::endl;
    }
}

[Cacsjep]

OK first, use compiled version that works without rpath and copy manually the .so files from .lib folder into this place where the binary is. To get sure it works and its Just an issue with rpath. Second use rpath directly with ./lib i dont know what $$orign does. When its compile linking is correct but when it does then not can load its just an rpath issue. What you can test when .so files are in same location as the binary

[Cacsjep]

We could also Talk in my discord Channel about acaps https://discord.com/invite/VHGqEKMf If you want