Recherche avancée

Sur d’autres sites (2578)

• Main process is held by ffmpeg command

  6 octobre 2024, par Michael Lopez

  I created a python program for handling my Arlo Camera. To do that I have been using the pyaarlo library (https://github.com/twrecked/pyaarlo) to catch camera's events.
The goal is to monitor if there is an active stream on cameras, get the RTSP stream url and reStream it to a HLS playlist for local usage.

  


  Here the python code :

  


  import asyncio
from decouple import config
import logging
from my_pyaarlo import PyArlo
import urllib.parse
from queue import Queue
import signal

# Read config from ENV (unchanged)
ARLO_USER = config('ARLO_USER')
ARLO_PASS = config('ARLO_PASS')
IMAP_HOST = config('IMAP_HOST')
IMAP_USER = config('IMAP_USER')
IMAP_PASS = config('IMAP_PASS')
DEBUG = config('DEBUG', default=False, cast=bool)
PYAARLO_BACKEND = config('PYAARLO_BACKEND', default=None)
PYAARLO_REFRESH_DEVICES = config('PYAARLO_REFRESH_DEVICES', default=0, cast=int)
PYAARLO_STREAM_TIMEOUT = config('PYAARLO_STREAM_TIMEOUT', default=0, cast=int)
PYAARLO_STORAGE_DIR = config('PYAARLO_STORAGE_DIR', default=None)
PYAARLO_ECDH_CURVE = config('PYAARLO_ECDH_CURVE', default=None)

# Initialize logging
logging.basicConfig(
    level=logging.DEBUG if DEBUG else logging.INFO,
    format='%(asctime)s [%(levelname)s] %(name)s: %(message)s'
)
logger = logging.getLogger(__name__)

ffmpeg_processes = {}
event_queue = Queue()
shutdown_event = asyncio.Event()

async def handle_idle_event(camera):
    logger.info(f"Idle event detected for camera: {camera.name}")
    await stop_ffmpeg_stream(camera.name)

async def get_stream_url(camera):
    try:
        # Attempt to get the stream URL
        stream_url = await asyncio.to_thread(camera.get_stream()
        if stream_url:
            return stream_url
        else:
            logger.warning(f"Unable to get stream URL for {camera.name}. Stream might not be active.")
            return None
    except Exception as e:
        logger.error(f"Error getting stream URL for {camera.name}: {e}")
        return None

async def handle_user_stream_active_event(camera):
    logger.info(f"User stream active event detected for camera: {camera.name}")

    # Get the stream URL
    stream_url = await get_stream_url(camera)
    if stream_url:
        logger.info(f"Stream URL for {camera.name}: {stream_url}")
        await start_ffmpeg_stream(camera.name, stream_url)
    else:
        logger.warning(f"No stream URL available for {camera.name}")

async def event_handler(device, attr, value):
    logger.debug(f"Event: {device.name}, Attribute: {attr}, Value: {value}")
    if attr == 'activityState':
        if value == 'idle':
            await handle_idle_event(device)
        elif value in ['userStreamActive']:
            await handle_user_stream_active_event(device)
    elif attr == 'mediaUploadNotification':
        logger.info(f"Media uploaded for camera: {device.name}")

def sync_event_handler(device, attr, value):
    # This function will be called by PyArlo's synchronous callbacks
    event_queue.put((device, attr, value))

async def process_event_queue():
    while not shutdown_event.is_set():
        try:
            if not event_queue.empty():
                device, attr, value = event_queue.get()
                await event_handler(device, attr, value)
            await asyncio.sleep(0.1)  # Small delay to prevent busy-waiting
        except asyncio.CancelledError:
            break
        except Exception as e:
            logger.error(f"Error processing event: {e}")

async def display_status(arlo):
    while not shutdown_event.is_set():
        print("\n--- Camera Statuses ---")
        for camera in arlo.cameras:
            print(f"{camera.name}: {camera.state}")
        print("------------------------")
        await asyncio.sleep(5)

async def start_ffmpeg_stream(camera_name, stream_url):
    if camera_name not in ffmpeg_processes:
        output_hls = f"/tmp/{camera_name}.m3u8"

        try:
            new_url = urllib.parse.quote(stream_url.encode(), safe=':/?&=')
            logger.info(f"NEW_URL: {new_url}")

            ffmpeg_cmd = [
                "ffmpeg", "-hide_banner", "-loglevel", "quiet", "-nostats", "-nostdin", "-y", "-re",
                "-i", new_url,
                "-c:v", "libx264", "-preset", "veryfast",
                "-an", "-sn",
                "-f", "hls", "-hls_time", "4", "-hls_list_size", "10",
                "-hls_flags", "delete_segments", output_hls,
            ]
            logger.info(f"Starting FFmpeg command: {ffmpeg_cmd}")
            
            process = await asyncio.create_subprocess_exec(
                *ffmpeg_cmd,
                stdout=asyncio.subprocess.DEVNULL,
                stderr=asyncio.subprocess.DEVNULL
            )
            ffmpeg_processes[camera_name] = process
            logger.info(f"Started ffmpeg process with PID: {process.pid}")

        except Exception as e:
            logger.error(f"Error starting FFmpeg for {camera_name}: {e}")

async def stop_ffmpeg_stream(camera_name):
    logger.info(f"Stopping ffmpeg process for {camera_name}")
    ffmpeg_process = ffmpeg_processes.pop(camera_name, None)
    if ffmpeg_process:
        ffmpeg_process.terminate()

        try:
            await ffmpeg_process.wait()
            logger.info(f"{camera_name} stopped successfully")
        except Exception as e:
            print(f"FFMPEG Process didn't stop in time, forcefully terminating: {e}")
            ffmpeg_process.kill()
    else:
        logger.info(f"FFmpeg process for {camera_name} already stopped")

async def shutdown(signal, loop):
    logger.info(f"Received exit signal {signal.name}...")
    shutdown_event.set()
    tasks = [t for t in asyncio.all_tasks() if t is not asyncio.current_task()]
    [task.cancel() for task in tasks]
    logger.info(f"Cancelling {len(tasks)} outstanding tasks")
    await asyncio.gather(*tasks, return_exceptions=True)
    loop.stop()

async def main():
    # Initialize PyArlo
    arlo_args = {
        'username': ARLO_USER,
        'password': ARLO_PASS,
        'tfa_source': 'imap',
        'tfa_type': 'email',
        'tfa_host': IMAP_HOST,
        'tfa_username': IMAP_USER,
        'tfa_password': IMAP_PASS,
        'save_session': True,
        'verbose_debug': DEBUG
    }

    # Add optional arguments
    for arg, value in [
        ('refresh_devices_every', PYAARLO_REFRESH_DEVICES),
        ('stream_timeout', PYAARLO_STREAM_TIMEOUT),
        ('backend', PYAARLO_BACKEND),
        ('storage_dir', PYAARLO_STORAGE_DIR),
        ('ecdh_curve', PYAARLO_ECDH_CURVE)
    ]:
        if value:
            arlo_args[arg] = value
    
    try:
        arlo = await asyncio.to_thread(PyArlo, **arlo_args)
    except Exception as e:
        logger.error(f"Failed to initialize PyArlo: {e}")
        return

    logger.info("Connected to Arlo. Monitoring events...")

    # Register event handlers for each camera
    for camera in arlo.cameras:
        camera.add_attr_callback('*', sync_event_handler)

    # Start the status display task
    status_task = asyncio.create_task(display_status(arlo))

    # Start the event processing task
    event_processing_task = asyncio.create_task(process_event_queue())

    # Set up signal handlers
    loop = asyncio.get_running_loop()
    for s in (signal.SIGHUP, signal.SIGTERM, signal.SIGINT):
        loop.add_signal_handler(
            s, lambda s=s: asyncio.create_task(shutdown(s, loop)))

    try:
        # Keep the main coroutine running
        while not shutdown_event.is_set():
            try:
                await asyncio.sleep(1)
            except asyncio.CancelledError:
                break
    except Exception as e:
        logger.error(f"Unexpected error in main loop: {e}")
    finally:
        logger.info("Shutting down...")
        for camera_name in list(ffmpeg_processes.keys()):
            await stop_ffmpeg_stream(camera_name)
        
        # Cancel and wait for all tasks
        tasks = [status_task, event_processing_task]
        for task in tasks:
            if not task.done():
                task.cancel()
        await asyncio.gather(*tasks, return_exceptions=True)
        
        logger.info("Program terminated.")

if __name__ == "__main__":
    try:
        asyncio.run(main())
    except KeyboardInterrupt:
        logger.info("Keyboard interrupt received. Exiting.")
    except Exception as e:
        logger.error(f"Unhandled exception: {e}")
    finally:
        logger.info("Program exit complete.")


  


  My issue is about the ffmpeg command which is hold the main process (or the event loop) when it runs, blocking the events coming from the pyaarlo library. The state of the camera continues to work with the good information.

  


  I tried lot of things, without asyncio, with multiprocessing, with subprocess, ... the behavior is always the same. In some cases, I received the idle event after the key interrupt.

  


  Another information :

  


  

  • When I stop the active stream, the event is not received but when I start the stream just after, that event is received.

  


  • When I run the same ffmpeg command but with a local long video file, everything is Ok. So, it why I guess that the ffmpeg command is impacting the main process.

  


  


  I succedeed in running the ffmpeg command with rtsp url stream but without a loop event monitoring :

  


  import asyncio
import signal
import sys
import os

async def run_infinite_command():
    # Start a simple HTTP server as our "infinite" command
    url = "rstp://localhost:8554/camera1/stream" # it is a fake url
    ffmpeg_cmd = [
        "ffmpeg", "-re", "-i", url,
        "-c:v", "libx264", "-preset", "veryfast",
        "-c:a", "copy",
        "-f", "hls", "-hls_time", "4", "-hls_list_size", "10",
        "-hls_flags", "delete_segments", "/tmp/output.m3u8"
    ]
    
    process = await asyncio.create_subprocess_exec(
        *ffmpeg_cmd,
        stdout=asyncio.subprocess.DEVNULL,
        stderr=asyncio.subprocess.DEVNULL
    )
    
    print(f"Started HTTP server with PID: {process.pid}")
    return process

async def main():
    # Start the infinite command
    process = await run_infinite_command()

    # Run the main loop for a few seconds
    for i in range(10):
        print(f"Main loop iteration {i+1}")
        await asyncio.sleep(1)

    # Stop the infinite command
    print("Stopping the HTTP server...")
    if sys.platform == "win32":
        # On Windows, we need to use CTRL_C_EVENT
        os.kill(process.pid, signal.CTRL_C_EVENT)
    else:
        # On Unix-like systems, we can use SIGTERM
        process.send_signal(signal.SIGTERM)

    # Wait for the process to finish
    try:
        await asyncio.wait_for(process.wait(), timeout=5.0)
        print("HTTP server stopped successfully")
    except asyncio.TimeoutError:
        print("HTTP server didn't stop in time, forcefully terminating")
        process.kill()

    print("Program finished")

if __name__ == "__main__":
    asyncio.run(main())


  


  With this script, the ffmpeg command is correctly launched and terminated after the for loop.

  


  Could you help ?

  


• [ffmpeg][asyncio] main process is held by ffmpeg command

  5 octobre 2024, par Michael Lopez

  I created a python program for handling my Arlo Camera. To do that I have been using the pyaarlo library (https://github.com/twrecked/pyaarlo) to catch camera's events.
The goal is to monitor if there is an active stream on cameras, get the RTSP stream url and reStream it to a HLS playlist for local usage.

  


  Here the python code :

  


  import asyncio
from decouple import config
import logging
from my_pyaarlo import PyArlo
import urllib.parse
from queue import Queue
import signal

# Read config from ENV (unchanged)
ARLO_USER = config('ARLO_USER')
ARLO_PASS = config('ARLO_PASS')
IMAP_HOST = config('IMAP_HOST')
IMAP_USER = config('IMAP_USER')
IMAP_PASS = config('IMAP_PASS')
DEBUG = config('DEBUG', default=False, cast=bool)
PYAARLO_BACKEND = config('PYAARLO_BACKEND', default=None)
PYAARLO_REFRESH_DEVICES = config('PYAARLO_REFRESH_DEVICES', default=0, cast=int)
PYAARLO_STREAM_TIMEOUT = config('PYAARLO_STREAM_TIMEOUT', default=0, cast=int)
PYAARLO_STORAGE_DIR = config('PYAARLO_STORAGE_DIR', default=None)
PYAARLO_ECDH_CURVE = config('PYAARLO_ECDH_CURVE', default=None)

# Initialize logging
logging.basicConfig(
    level=logging.DEBUG if DEBUG else logging.INFO,
    format='%(asctime)s [%(levelname)s] %(name)s: %(message)s'
)
logger = logging.getLogger(__name__)

ffmpeg_processes = {}
event_queue = Queue()
shutdown_event = asyncio.Event()

async def handle_idle_event(camera):
    logger.info(f"Idle event detected for camera: {camera.name}")
    await stop_ffmpeg_stream(camera.name)

async def get_stream_url(camera):
    try:
        # Attempt to get the stream URL
        stream_url = await asyncio.to_thread(camera.get_stream()
        if stream_url:
            return stream_url
        else:
            logger.warning(f"Unable to get stream URL for {camera.name}. Stream might not be active.")
            return None
    except Exception as e:
        logger.error(f"Error getting stream URL for {camera.name}: {e}")
        return None

async def handle_user_stream_active_event(camera):
    logger.info(f"User stream active event detected for camera: {camera.name}")

    # Get the stream URL
    stream_url = await get_stream_url(camera)
    if stream_url:
        logger.info(f"Stream URL for {camera.name}: {stream_url}")
        await start_ffmpeg_stream(camera.name, stream_url)
    else:
        logger.warning(f"No stream URL available for {camera.name}")

async def event_handler(device, attr, value):
    logger.debug(f"Event: {device.name}, Attribute: {attr}, Value: {value}")
    if attr == 'activityState':
        if value == 'idle':
            await handle_idle_event(device)
        elif value in ['userStreamActive']:
            await handle_user_stream_active_event(device)
    elif attr == 'mediaUploadNotification':
        logger.info(f"Media uploaded for camera: {device.name}")

def sync_event_handler(device, attr, value):
    # This function will be called by PyArlo's synchronous callbacks
    event_queue.put((device, attr, value))

async def process_event_queue():
    while not shutdown_event.is_set():
        try:
            if not event_queue.empty():
                device, attr, value = event_queue.get()
                await event_handler(device, attr, value)
            await asyncio.sleep(0.1)  # Small delay to prevent busy-waiting
        except asyncio.CancelledError:
            break
        except Exception as e:
            logger.error(f"Error processing event: {e}")

async def display_status(arlo):
    while not shutdown_event.is_set():
        print("\n--- Camera Statuses ---")
        for camera in arlo.cameras:
            print(f"{camera.name}: {camera.state}")
        print("------------------------")
        await asyncio.sleep(5)

async def start_ffmpeg_stream(camera_name, stream_url):
    if camera_name not in ffmpeg_processes:
        output_hls = f"/tmp/{camera_name}.m3u8"

        try:
            new_url = urllib.parse.quote(stream_url.encode(), safe=':/?&=')
            logger.info(f"NEW_URL: {new_url}")

            ffmpeg_cmd = [
                "ffmpeg", "-hide_banner", "-loglevel", "quiet", "-nostats", "-nostdin", "-y", "-re",
                "-i", new_url,
                "-c:v", "libx264", "-preset", "veryfast",
                "-an", "-sn",
                "-f", "hls", "-hls_time", "4", "-hls_list_size", "10",
                "-hls_flags", "delete_segments", output_hls,
            ]
            logger.info(f"Starting FFmpeg command: {ffmpeg_cmd}")
            
            process = await asyncio.create_subprocess_exec(
                *ffmpeg_cmd,
                stdout=asyncio.subprocess.DEVNULL,
                stderr=asyncio.subprocess.DEVNULL
            )
            ffmpeg_processes[camera_name] = process
            logger.info(f"Started ffmpeg process with PID: {process.pid}")

        except Exception as e:
            logger.error(f"Error starting FFmpeg for {camera_name}: {e}")

async def stop_ffmpeg_stream(camera_name):
    logger.info(f"Stopping ffmpeg process for {camera_name}")
    ffmpeg_process = ffmpeg_processes.pop(camera_name, None)
    if ffmpeg_process:
        ffmpeg_process.terminate()

        try:
            await ffmpeg_process.wait()
            logger.info(f"{camera_name} stopped successfully")
        except Exception as e:
            print(f"FFMPEG Process didn't stop in time, forcefully terminating: {e}")
            ffmpeg_process.kill()
    else:
        logger.info(f"FFmpeg process for {camera_name} already stopped")

async def shutdown(signal, loop):
    logger.info(f"Received exit signal {signal.name}...")
    shutdown_event.set()
    tasks = [t for t in asyncio.all_tasks() if t is not asyncio.current_task()]
    [task.cancel() for task in tasks]
    logger.info(f"Cancelling {len(tasks)} outstanding tasks")
    await asyncio.gather(*tasks, return_exceptions=True)
    loop.stop()

async def main():
    # Initialize PyArlo
    arlo_args = {
        'username': ARLO_USER,
        'password': ARLO_PASS,
        'tfa_source': 'imap',
        'tfa_type': 'email',
        'tfa_host': IMAP_HOST,
        'tfa_username': IMAP_USER,
        'tfa_password': IMAP_PASS,
        'save_session': True,
        'verbose_debug': DEBUG
    }

    # Add optional arguments
    for arg, value in [
        ('refresh_devices_every', PYAARLO_REFRESH_DEVICES),
        ('stream_timeout', PYAARLO_STREAM_TIMEOUT),
        ('backend', PYAARLO_BACKEND),
        ('storage_dir', PYAARLO_STORAGE_DIR),
        ('ecdh_curve', PYAARLO_ECDH_CURVE)
    ]:
        if value:
            arlo_args[arg] = value
    
    try:
        arlo = await asyncio.to_thread(PyArlo, **arlo_args)
    except Exception as e:
        logger.error(f"Failed to initialize PyArlo: {e}")
        return

    logger.info("Connected to Arlo. Monitoring events...")

    # Register event handlers for each camera
    for camera in arlo.cameras:
        camera.add_attr_callback('*', sync_event_handler)

    # Start the status display task
    status_task = asyncio.create_task(display_status(arlo))

    # Start the event processing task
    event_processing_task = asyncio.create_task(process_event_queue())

    # Set up signal handlers
    loop = asyncio.get_running_loop()
    for s in (signal.SIGHUP, signal.SIGTERM, signal.SIGINT):
        loop.add_signal_handler(
            s, lambda s=s: asyncio.create_task(shutdown(s, loop)))

    try:
        # Keep the main coroutine running
        while not shutdown_event.is_set():
            try:
                await asyncio.sleep(1)
            except asyncio.CancelledError:
                break
    except Exception as e:
        logger.error(f"Unexpected error in main loop: {e}")
    finally:
        logger.info("Shutting down...")
        for camera_name in list(ffmpeg_processes.keys()):
            await stop_ffmpeg_stream(camera_name)
        
        # Cancel and wait for all tasks
        tasks = [status_task, event_processing_task]
        for task in tasks:
            if not task.done():
                task.cancel()
        await asyncio.gather(*tasks, return_exceptions=True)
        
        logger.info("Program terminated.")

if __name__ == "__main__":
    try:
        asyncio.run(main())
    except KeyboardInterrupt:
        logger.info("Keyboard interrupt received. Exiting.")
    except Exception as e:
        logger.error(f"Unhandled exception: {e}")
    finally:
        logger.info("Program exit complete.")


  


  My issue is about the ffmpeg command which is hold the main process (or the event loop) when it runs, blocking the events coming from the pyaarlo library. The state of the camera continues to work with the good information.

  


  I tried lot of things, without asyncio, with multiprocessing, with subprocess, ... the behavior is always the same. In some cases, I received the idle event after the key interrupt.

  


  Another information :

  


  

  • When I stop the active stream, the event is not received but when I start the stream just after, that event is received.

  


  • When I run the same ffmpeg command but with a local long video file, everything is Ok. So, it why I guess that the ffmpeg command is impacting the main process.

  


  


  I succedeed in running the ffmpeg command with rtsp url stream but without a loop event monitoring :

  


  import asyncio
import signal
import sys
import os

async def run_infinite_command():
    # Start a simple HTTP server as our "infinite" command
    url = "rstp://localhost:8554/camera1/stream" # it is a fake url
    ffmpeg_cmd = [
        "ffmpeg", "-re", "-i", url,
        "-c:v", "libx264", "-preset", "veryfast",
        "-c:a", "copy",
        "-f", "hls", "-hls_time", "4", "-hls_list_size", "10",
        "-hls_flags", "delete_segments", "/tmp/output.m3u8"
    ]
    
    process = await asyncio.create_subprocess_exec(
        *ffmpeg_cmd,
        stdout=asyncio.subprocess.DEVNULL,
        stderr=asyncio.subprocess.DEVNULL
    )
    
    print(f"Started HTTP server with PID: {process.pid}")
    return process

async def main():
    # Start the infinite command
    process = await run_infinite_command()

    # Run the main loop for a few seconds
    for i in range(10):
        print(f"Main loop iteration {i+1}")
        await asyncio.sleep(1)

    # Stop the infinite command
    print("Stopping the HTTP server...")
    if sys.platform == "win32":
        # On Windows, we need to use CTRL_C_EVENT
        os.kill(process.pid, signal.CTRL_C_EVENT)
    else:
        # On Unix-like systems, we can use SIGTERM
        process.send_signal(signal.SIGTERM)

    # Wait for the process to finish
    try:
        await asyncio.wait_for(process.wait(), timeout=5.0)
        print("HTTP server stopped successfully")
    except asyncio.TimeoutError:
        print("HTTP server didn't stop in time, forcefully terminating")
        process.kill()

    print("Program finished")

if __name__ == "__main__":
    asyncio.run(main())


  


  With this script, the ffmpeg command is correctly launched and terminated after the for loop.

  


  Could you help ?

  


• "undefined reference to av···@···"ffmpeg error，when i cross compile opencv4.5.3 which include ffmpeg lib

  11 mai 2024, par caiping Peng

  everyone,It is sorry to bother you,but i need some help.
I'm working on an embedded deployment project,doing object detection work to real-time video stream. So I have to port my c++ inference prog to RKNN1808 platform. I compile this program with CMake tool,but I cant finish my work because opencv lib cant be compiled rightly.
To FFmpeg,my configure commend is following :

  


  ./configure --enable-cross-compile --cross-prefix=/home/midsummer/Tool/gcc-linaro-6.3.1-2017.05-x86_64_aarch64-linux-gnu/bin/aarch64-linux-gnu- --target-os=linux --arch=aarch64 --prefix=/usr/local/ffmpeg  --enable-shared


  


  then I am gonna show you the ffmpeg version :

  


  libavutil      56. 70.100
libavcodec     58.134.100
libavformat    58. 76.100
libavdevice    58. 13.100
libavfilter     7.110.100
libswscale      5.  9.100
libswresample   3.  9.100
libpostproc    55.  9.100


  


  next ,I use following commend to build cmake project :

  


  cmake -D CMAKE_BUILD_TYPE=RELEASE  -D CMAKE_C_COMPILER=/home/midsummer/Tool/gcc-linaro-6.3.1-2017.05-x86_64_aarch64-linux-gnu/bin/aarch64-linux-gnu-gcc -D CMAKE_CXX_COMPILER=/home/midsummer/Tool/gcc-linaro-6.3.1-2017.05-x86_64_aarch64-linux-gnu/bin/aarch64-linux-gnu-g++ -D BUILD_SHARED_LIBS=ON -D CMAKE_CXX_FLAGS=-fPIC -D CMAKE_C_FLAGS=-fPIC -D CMAKE_EXE_LINKER_FLAGS=-lpthread -ldl -D ENABLE_PIC=ON -D WITH_1394=OFF -D WITH_ARAVIS=OFF -D WITH_ARITH_DEC=ON -D WITH_ARITH_ENC=ON -D WITH_CLP=OFF -D WITH_CUBLAS=OFF -D WITH_CUDA=OFF -D WITH_CUFFT=OFF -D WITH_FFMPEG=ON -D WITH_GSTREAMER=ON -D WITH_GSTREAMER_0_10=OFF -D WITH_HALIDE=OFF -D WITH_HPX=OFF -D WITH_IMGCODEC_HDR=ON -D WITH_IMGCODEC_PXM=ON -D WITH_IMGCODEC_SUNRASTER=ON -D WITH_INF_ENGINE=OFF -D WITH_IPP=OFF -D WITH_ITT=OFF -D WITH_JASPER=ON -D WITH_JPEG=ON -D WITH_LAPACK=ON -D WITH_LIBREALSENSE=OFF -D WITH_NVCUVID=OFF -D WITH_OPENCL=OFF -D WITH_OPENCLAMDBLAS=OFF -D WITH_OPENCLAMDFFT=OFF -D WITH_OPENCL_SVM=OFF -D WITH_OPENEXR=OFF -D WITH_OPENGL=OFF -D WITH_OPENMP=OFF -D WITH_OPENNNI=OFF -D WITH_OPENNNI2=OFF -D WITH_OPENVX=OFF -D WITH_PNG=OFF -D WITH_PROTOBUF=OFF -D WITH_PTHREADS_PF=ON -D WITH_PVAPI=OFF -D WITH_QT=OFF -D WITH_QUIRC=OFF  -D WITH_TBB=OFF -D WITH_TIFF=ON -D WITH_VULKAN=OFF -D WITH_WEBP=ON -D WITH_XIMEA=OFF -D CMAKE_INSTALL_PREFIX=../CrossCompileResult  -D WITH_GTK=OFF  -D BUILD_opencv_dnn=OFF ..


  


  following is the outpt about FFmpeg :

  


  --   Video I/O:
--     FFMPEG:                      YES
--       avcodec:                   YES (58.134.100)
--       avformat:                  YES (58.76.100)
--       avutil:                    YES (56.70.100)
--       swscale:                   YES (5.9.100)
--       avresample:                NO
--     GStreamer:                   NO
--     v4l/v4l2:                    YES (linux/videodev2.h)



  


  After building the cmake project,I compiled this project with comment 【make -j16】.After not so long time,I got the Error :

  


  [ 49%] Linking CXX executable ../../bin/opencv_annotation
[ 49%] Building CXX object modules/ts/CMakeFiles/opencv_ts.dir/src/ts_tags.cpp.o
[ 49%] Built target opencv_annotation
[ 49%] Linking CXX executable ../../bin/opencv_visualisation
/home/midsummer/Tool/gcc-linaro-6.3.1-2017.05-x86_64_aarch64-linux-gnu/bin/../lib/gcc/aarch64-linux-gnu/6.3.1/../../../../aarch64-linux-gnu/bin/ld: warning: libavcodec.so.58, needed by ../../lib/libopencv_videoio.so.4.5.3, not found (try using -rpath or -rpath-link)
/home/midsummer/Tool/gcc-linaro-6.3.1-2017.05-x86_64_aarch64-linux-gnu/bin/../lib/gcc/aarch64-linux-gnu/6.3.1/../../../../aarch64-linux-gnu/bin/ld: warning: libavformat.so.58, needed by ../../lib/libopencv_videoio.so.4.5.3, not found (try using -rpath or -rpath-link)
/home/midsummer/Tool/gcc-linaro-6.3.1-2017.05-x86_64_aarch64-linux-gnu/bin/../lib/gcc/aarch64-linux-gnu/6.3.1/../../../../aarch64-linux-gnu/bin/ld: warning: libavutil.so.56, needed by ../../lib/libopencv_videoio.so.4.5.3, not found (try using -rpath or -rpath-link)
/home/midsummer/Tool/gcc-linaro-6.3.1-2017.05-x86_64_aarch64-linux-gnu/bin/../lib/gcc/aarch64-linux-gnu/6.3.1/../../../../aarch64-linux-gnu/bin/ld: warning: libswscale.so.5, needed by ../../lib/libopencv_videoio.so.4.5.3, not found (try using -rpath or -rpath-link)
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_init_packet@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_get_riff_video_tags@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_send_packet@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_receive_packet@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_get_mov_video_tags@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_find_decoder@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_find_decoder_by_name@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_frame_alloc@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_get_name@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwframe_transfer_data@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_malloc@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avio_open@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_alloc_context@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_sub_q@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_network_init@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_packet_free@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_flush_buffers@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_find_encoder@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `sws_getContext@LIBSWSCALE_5'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_receive_frame@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_write_frame@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_close_input@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_seek_frame@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `sws_freeContext@LIBSWSCALE_5'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_dict_set@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_descriptor_get_by_name@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `sws_scale@LIBSWSCALE_5'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_packet_unref@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_dict_parse_string@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_frame_get_buffer@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_freep@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_find_stream_info@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_read_frame@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_free_context@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_default_get_format@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwframe_ctx_init@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_register_all@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_free@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwframe_get_buffer@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_guess_sample_aspect_ratio@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_new_stream@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwframe_constraints_free@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwdevice_ctx_create_derived@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_frame_unref@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_buffer_unref@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_write_trailer@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_packet_rescale_ts@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_bsf_get_by_name@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_send_frame@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_get_hw_config@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_buffer_ref@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_dict_get@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_bsf_free@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_codec_is_decoder@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_open_input@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_lockmgr_register@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_packet_alloc@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwframe_ctx_create_derived@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_bsf_send_packet@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_bsf_alloc@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_log_set_level@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_image_get_buffer_size@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_open2@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_codec_is_encoder@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_guess_format@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_image_fill_arrays@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_bsf_receive_packet@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `sws_getCachedContext@LIBSWSCALE_5'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_codec_get_tag@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwdevice_get_hwframe_constraints@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwdevice_ctx_create@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_codec_iterate@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_log_set_callback@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_opt_set@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_codec_get_id@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avformat_write_header@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_parameters_copy@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_pix_fmt_to_codec_tag@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwframe_ctx_alloc@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_mallocz@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_find_input_format@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_dict_free@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_get_hw_frames_parameters@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwdevice_get_type_name@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avio_close@LIBAVFORMAT_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_frame_free@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_bsf_init@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_close@LIBAVCODEC_58'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `av_hwdevice_find_type_by_name@LIBAVUTIL_56'
../../lib/libopencv_videoio.so.4.5.3: undefined reference to `avcodec_get_context_defaults3@LIBAVCODEC_58'
collect2: error: ld returned 1 exit status
make[2]: *** [apps/visualisation/CMakeFiles/opencv_visualisation.dir/build.make:89: bin/opencv_visualisation] Error 1
make[1]: *** [CMakeFiles/Makefile2:3357: apps/visualisation/CMakeFiles/opencv_visualisation.dir/all] Error 2
make[1]: *** Waiting for unfinished jobs....
[ 49%] Linking CXX shared library ../../lib/libopencv_calib3d.so
[ 49%] Built target opencv_calib3d
[ 50%] Linking CXX static library ../../lib/libopencv_ts.a
[ 50%] Built target opencv_ts
make: *** [Makefile:163: all] Error 2



  


  I dont know what's wrong with it,It has confused me for a few days,I real hope someone can help me solve the prob.
I promise the the ffmpeg version match the version of opencv strictly,promising the PKG_CONFIG_PATH is right.

  


  I have tried many method like changing opencv version or ffmpeg version,recompiling the ffmpeg,changing PKG_CONFIG_PATH,coping ffmpeg pc file from /usr/local/ffmpeg/lib/pkgconfig to /usr/local/lib/pkgconfig.
I hope somebody can give some idea about how to solve this problem.