[BUG] Cannot stream MJPEG

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#788 opened on Sep 4, 2023 4 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty: 4/5
Estimated time: 3-5 days
Newbie friendliness: 35/100

Issue type: Bug
Clarity: Mostly clear
Activity status: Stale
Tech stack: python
Domain: backend

Research direction

Start by reproducing the issue with the supplied Picamera2 script, especially create_video_configuration with the USB camera's MJPEG and YUYV formats. Trace the configuration and recording entry points involved in format validation. Done means USB video capture can be configured and streamed, or the supported limitation and workaround are documented.

Written by the indexing model from the issue text.

Description

Describe the bug
Testing streaming of USB camera. Works with Pi camera but not USB.
I realize that full support for USB may not be available, but it seems this is a straightforward use case that should work.

USB camera displays stills in preview with picam.create_preview_configuration({"format": "MJPEG"})

Pi camera works fine with:
picam2.configure(picam2.create_video_configuration()) but not
picam2.configure(picam2.create_video_configuration({"format": "MJPEG"}))

USB camera throws an error:
ValueError: Invalid format: MJPEG. Valid formats are: ...

This occures when attempting to capture video with either:
picam2.configure(picam2.create_video_configuration())
or
picam2.configure(picam2.create_video_configuration({"format": "MJPEG"}))

I tried YUYV (a valid format and reported by camera as available)
picam2.configure(picam2.create_video_configuration({"format": "YUYV"}))
This gave a different error (see below)

To Reproduce
This following sample code is taken from one of the examples with some added code to provide info about the cameras.
All changes are at the end of the code.

#!/usr/bin/python3

# Mostly copied from https://picamera.readthedocs.io/en/release-1.13/recipes2.html
# Run this script, then point a web browser at http:<this-ip-address>:8000
# Note: needs simplejpeg to be installed (pip3 install simplejpeg).

import io
import logging
import socketserver
from http import server
from threading import Condition

from picamera2 import Picamera2
from picamera2.encoders import JpegEncoder
from picamera2.outputs import FileOutput

PAGE = """\
<html>
<head>
<title>picamera2 MJPEG streaming demo</title>
</head>
<body>
<h1>Picamera2 MJPEG Streaming Demo</h1>
<img src="stream.mjpg" width="640" height="480" />
</body>
</html>
"""


class StreamingOutput(io.BufferedIOBase):
    def __init__(self):
        self.frame = None
        self.condition = Condition()

    def write(self, buf):
        with self.condition:
            self.frame = buf
            self.condition.notify_all()


class StreamingHandler(server.BaseHTTPRequestHandler):
    def do_GET(self):
        if self.path == '/':
            self.send_response(301)
            self.send_header('Location', '/index.html')
            self.end_headers()
        elif self.path == '/index.html':
            content = PAGE.encode('utf-8')
            self.send_response(200)
            self.send_header('Content-Type', 'text/html')
            self.send_header('Content-Length', len(content))
            self.end_headers()
            self.wfile.write(content)
        elif self.path == '/stream.mjpg':
            self.send_response(200)
            self.send_header('Age', 0)
            self.send_header('Cache-Control', 'no-cache, private')
            self.send_header('Pragma', 'no-cache')
            self.send_header('Content-Type', 'multipart/x-mixed-replace; boundary=FRAME')
            self.end_headers()
            try:
                while True:
                    with output.condition:
                        output.condition.wait()
                        frame = output.frame
                    self.wfile.write(b'--FRAME\r\n')
                    self.send_header('Content-Type', 'image/jpeg')
                    self.send_header('Content-Length', len(frame))
                    self.end_headers()
                    self.wfile.write(frame)
                    self.wfile.write(b'\r\n')
            except Exception as e:
                logging.warning(
                    'Removed streaming client %s: %s',
                    self.client_address, str(e))
        else:
            self.send_error(404)
            self.end_headers()


class StreamingServer(socketserver.ThreadingMixIn, server.HTTPServer):
    allow_reuse_address = True
    daemon_threads = True
    
    
###  Starts here
available_cameras = Picamera2.global_camera_info()

for cam in range(len(available_cameras)):
    print(f'---- Details for camera {cam}')
    picam2 = Picamera2(cam)
    print(f'Camera: {available_cameras[cam]["Model"]}')
    print(picam2.sensor_modes)
    print(picam2.sensor_resolution)
    print(picam2.create_video_configuration())
    picam2.close()
    print('\n\n\n')


picam2 = Picamera2(1)
# picam2.configure(picam2.create_video_configuration())
picam2.configure(picam2.create_video_configuration({"format": "MJPEG"}))
output = StreamingOutput()
picam2.start_recording(JpegEncoder(), FileOutput(output))

try:
    address = ('', 8081)
    server = StreamingServer(address, StreamingHandler)
    server.serve_forever()
finally:
    picam2.stop_recording()

Expected behaviour
That it works :-) or maybe a workaround?

Console Output, Screenshots
I added a few spaces to the console output for ease of reading.

I notice that the sensor.modes information from the pi camera (lots of it) is very different to that of the USB camera([{'format': 'MJPEG'}, {'format': 'YUYV'}]).

The output using picam2.configure(picam2.create_video_configuration()) or
picam2.configure(picam2.create_video_configuration({"format": "MJPEG"}))

[43:40:01.815888245] [7540]  INFO Camera camera_manager.cpp:297 libcamera v0.0.5+83-bde9b04f
[43:40:01.891635938] [7541]  WARN RPI vc4.cpp:383 Mismatch between Unicam and CamHelper for embedded data usage!
[43:40:01.893642427] [7541]  INFO RPI vc4.cpp:437 Registered camera /base/soc/i2c0mux/i2c@1/imx219@10 to Unicam device /dev/media3 and ISP device /dev/media0
[43:40:01.894019715] [7541]  INFO RPI pipeline_base.cpp:1101 Using configuration file '/usr/share/libcamera/pipeline/rpi/vc4/rpi_apps.yaml'



---- Details for camera 0
[43:40:01.974919645] [7540]  INFO Camera camera_manager.cpp:297 libcamera v0.0.5+83-bde9b04f
[43:40:02.047390862] [7544]  WARN RPI vc4.cpp:383 Mismatch between Unicam and CamHelper for embedded data usage!
[43:40:02.049173812] [7544]  INFO RPI vc4.cpp:437 Registered camera /base/soc/i2c0mux/i2c@1/imx219@10 to Unicam device /dev/media3 and ISP device /dev/media0
[43:40:02.049286571] [7544]  INFO RPI pipeline_base.cpp:1101 Using configuration file '/usr/share/libcamera/pipeline/rpi/vc4/rpi_apps.yaml'

Camera: imx219

[43:40:02.067818512] [7540]  INFO Camera camera.cpp:1033 configuring streams: (0) 640x480-XBGR8888 (1) 640x480-SBGGR10_CSI2P
[43:40:02.068869751] [7544]  INFO RPI vc4.cpp:565 Sensor: /base/soc/i2c0mux/i2c@1/imx219@10 - Selected sensor format: 640x480-SBGGR10_1X10 - Selected unicam format: 640x480-pBAA
[43:40:02.092751166] [7540]  INFO Camera camera.cpp:1033 configuring streams: (0) 640x480-XBGR8888 (1) 1640x1232-SBGGR10_CSI2P
[43:40:02.093790374] [7544]  INFO RPI vc4.cpp:565 Sensor: /base/soc/i2c0mux/i2c@1/imx219@10 - Selected sensor format: 1640x1232-SBGGR10_1X10 - Selected unicam format: 1640x1232-pBAA
[43:40:02.130956077] [7540]  INFO Camera camera.cpp:1033 configuring streams: (0) 640x480-XBGR8888 (1) 1920x1080-SBGGR10_CSI2P
[43:40:02.132345645] [7544]  INFO RPI vc4.cpp:565 Sensor: /base/soc/i2c0mux/i2c@1/imx219@10 - Selected sensor format: 1920x1080-SBGGR10_1X10 - Selected unicam format: 1920x1080-pBAA
[43:40:02.186451899] [7540]  INFO Camera camera.cpp:1033 configuring streams: (0) 640x480-XBGR8888 (1) 3280x2464-SBGGR10_CSI2P
[43:40:02.187829697] [7544]  INFO RPI vc4.cpp:565 Sensor: /base/soc/i2c0mux/i2c@1/imx219@10 - Selected sensor format: 3280x2464-SBGGR10_1X10 - Selected unicam format: 3280x2464-pBAA
[43:40:02.261862148] [7540]  INFO Camera camera.cpp:1033 configuring streams: (0) 640x480-XBGR8888 (1) 640x480-SBGGR8
[43:40:02.276421161] [7544]  INFO RPI vc4.cpp:565 Sensor: /base/soc/i2c0mux/i2c@1/imx219@10 - Selected sensor format: 640x480-SBGGR8_1X8 - Selected unicam format: 640x480-BA81
[43:40:02.334499977] [7540]  INFO Camera camera.cpp:1033 configuring streams: (0) 640x480-XBGR8888 (1) 1640x1232-SBGGR8
[43:40:02.335554237] [7544]  INFO RPI vc4.cpp:565 Sensor: /base/soc/i2c0mux/i2c@1/imx219@10 - Selected sensor format: 1640x1232-SBGGR8_1X8 - Selected unicam format: 1640x1232-BA81
[43:40:02.380179080] [7540]  INFO Camera camera.cpp:1033 configuring streams: (0) 640x480-XBGR8888 (1) 1920x1080-SBGGR8
[43:40:02.381506306] [7544]  INFO RPI vc4.cpp:565 Sensor: /base/soc/i2c0mux/i2c@1/imx219@10 - Selected sensor format: 1920x1080-SBGGR8_1X8 - Selected unicam format: 1920x1080-BA81
[43:40:02.444123668] [7540]  INFO Camera camera.cpp:1033 configuring streams: (0) 640x480-XBGR8888 (1) 3280x2464-SBGGR8
[43:40:02.445836931] [7544]  INFO RPI vc4.cpp:565 Sensor: /base/soc/i2c0mux/i2c@1/imx219@10 - Selected sensor format: 3280x2464-SBGGR8_1X8 - Selected unicam format: 3280x2464-BA81
[{'format': SRGGB10_CSI2P, 'unpacked': 'SRGGB10', 'bit_depth': 10, 'size': (640, 480), 'fps': 103.33, 'crop_limits': (1000, 752, 1280, 960), 'exposure_limits': (75, None)}, {'format': SRGGB10_CSI2P, 'unpacked': 'SRGGB10', 'bit_depth': 10, 'size': (1640, 1232), 'fps': 41.85, 'crop_limits': (0, 0, 3280, 2464), 'exposure_limits': (75, 11766829, None)}, {'format': SRGGB10_CSI2P, 'unpacked': 'SRGGB10', 'bit_depth': 10, 'size': (1920, 1080), 'fps': 47.57, 'crop_limits': (680, 692, 1920, 1080), 'exposure_limits': (75, 11766829, None)}, {'format': SRGGB10_CSI2P, 'unpacked': 'SRGGB10', 'bit_depth': 10, 'size': (3280, 2464), 'fps': 21.19, 'crop_limits': (0, 0, 3280, 2464), 'exposure_limits': (75, 11766829, None)}, {'format': SRGGB8, 'unpacked': 'SRGGB8', 'bit_depth': 8, 'size': (640, 480), 'fps': 103.33, 'crop_limits': (1000, 752, 1280, 960), 'exposure_limits': (75, 11766829, None)}, {'format': SRGGB8, 'unpacked': 'SRGGB8', 'bit_depth': 8, 'size': (1640, 1232), 'fps': 41.85, 'crop_limits': (0, 0, 3280, 2464), 'exposure_limits': (75, 11766829, None)}, {'format': SRGGB8, 'unpacked': 'SRGGB8', 'bit_depth': 8, 'size': (1920, 1080), 'fps': 47.57, 'crop_limits': (680, 692, 1920, 1080), 'exposure_limits': (75, 11766829, None)}, {'format': SRGGB8, 'unpacked': 'SRGGB8', 'bit_depth': 8, 'size': (3280, 2464), 'fps': 21.19, 'crop_limits': (0, 0, 3280, 2464), 'exposure_limits': (75, 11766829, None)}]

(3280, 2464)

{'use_case': 'video', 'transform': <libcamera.Transform 'identity'>, 'colour_space': <libcamera.ColorSpace 'Rec709'>, 'buffer_count': 6, 'queue': True, 'main': {'format': 'XBGR8888', 'size': (1280, 720)}, 'lores': None, 'raw': {'format': 'SBGGR10_CSI2P', 'size': (1280, 720)}, 'controls': {'NoiseReductionMode': <NoiseReductionModeEnum.Fast: 1>, 'FrameDurationLimits': (33333, 33333)}, 'display': 'main', 'encode': 'main'}



---- Details for camera 1
[43:40:02.739877953] [7540]  INFO Camera camera_manager.cpp:297 libcamera v0.0.5+83-bde9b04f
[43:40:02.834190398] [7548]  WARN RPI vc4.cpp:383 Mismatch between Unicam and CamHelper for embedded data usage!
[43:40:02.836145065] [7548]  INFO RPI vc4.cpp:437 Registered camera /base/soc/i2c0mux/i2c@1/imx219@10 to Unicam device /dev/media3 and ISP device /dev/media0
[43:40:02.836309438] [7548]  INFO RPI pipeline_base.cpp:1101 Using configuration file '/usr/share/libcamera/pipeline/rpi/vc4/rpi_apps.yaml'

Camera: Microsoft LifeCam HD-3000: Mi

[{'format': 'MJPEG'}, {'format': 'YUYV'}]

(1280, 720)

{'use_case': 'video', 'transform': <libcamera.Transform 'identity'>, 'colour_space': <libcamera.ColorSpace 'Rec709'>, 'buffer_count': 6, 'queue': True, 'main': {'format': 'XBGR8888', 'size': (1280, 720)}, 'lores': None, 'raw': None, 'controls': {}, 'display': 'main', 'encode': 'main'}




[43:40:03.056194782] [7540]  INFO Camera camera_manager.cpp:297 libcamera v0.0.5+83-bde9b04f
[43:40:03.130713790] [7552]  WARN RPI vc4.cpp:383 Mismatch between Unicam and CamHelper for embedded data usage!
[43:40:03.132523094] [7552]  INFO RPI vc4.cpp:437 Registered camera /base/soc/i2c0mux/i2c@1/imx219@10 to Unicam device /dev/media3 and ISP device /dev/media0
[43:40:03.132719551] [7552]  INFO RPI pipeline_base.cpp:1101 Using configuration file '/usr/share/libcamera/pipeline/rpi/vc4/rpi_apps.yaml'
[43:40:03.159512706] [7540]  INFO Camera camera.cpp:1033 configuring streams: (0) 1280x720-MJPEG
Traceback (most recent call last):
  File "/home/pi/videostream/./videostream-lite.py", line 103, in <module>
    picam2.start_recording(JpegEncoder(), FileOutput(output))
  File "/usr/lib/python3/dist-packages/picamera2/picamera2.py", line 1597, in start_recording
    self.start_encoder(encoder, output, pts=pts, quality=quality, name=name)
  File "/usr/lib/python3/dist-packages/picamera2/picamera2.py", line 1518, in start_encoder
    _encoder.format = streams[name]['format']
  File "/usr/lib/python3/dist-packages/picamera2/encoders/encoder.py", line 156, in format
    formats.assert_format_valid(value)
  File "/usr/lib/python3/dist-packages/picamera2/formats.py", line 39, in assert_format_valid
    raise ValueError(f"Invalid format: {fmt}. Valid formats are: {ALL_FORMATS}")
ValueError: Invalid format: MJPEG. Valid formats are: {'NV21', 'YUYV', 'R12', 'RGB888', 'R10', 'R8_CSI2P', 'SRGGB10', 'SGBRG12', 'SGRBG8', 'SGBRG12_CSI2P', 'SGBRG10_CSI2P', 'SGRBG12_CSI2P', 'R12_CSI2P', 'SRGGB12_CSI2P', 'NV12', 'BGR888', 'SGRBG12', 'SGBRG8', 'SRGGB12', 'SGBRG10', 'SRGGB10_CSI2P', 'UYVY', 'VYUY', 'YVYU', 'SBGGR12_CSI2P', 'XRGB8888', 'R8', 'YVU420', 'XBGR8888', 'SGRBG10', 'SBGGR10', 'SBGGR10_CSI2P', 'SGRBG10_CSI2P', 'SBGGR12', 'SRGGB8', 'SBGGR8', 'R10_CSI2P', 'YUV420'}

The error using picam2.configure(picam2.create_video_configuration({"format": "YUYV"}))

[44:35:30.213029403] [8098]  INFO Camera camera_manager.cpp:297 libcamera v0.0.5+83-bde9b04f
[44:35:30.310570269] [8110]  WARN RPI vc4.cpp:383 Mismatch between Unicam and CamHelper for embedded data usage!
[44:35:30.312305189] [8110]  INFO RPI vc4.cpp:437 Registered camera /base/soc/i2c0mux/i2c@1/imx219@10 to Unicam device /dev/media3 and ISP device /dev/media0
[44:35:30.312428416] [8110]  INFO RPI pipeline_base.cpp:1101 Using configuration file '/usr/share/libcamera/pipeline/rpi/vc4/rpi_apps.yaml'
[44:35:30.337001871] [8098]  INFO Camera camera.cpp:1033 configuring streams: (0) 1280x720-YUYV
Traceback (most recent call last):
  File "/home/pi/videostream/./videostream-lite.py", line 104, in <module>
    picam2.start_recording(JpegEncoder(), FileOutput(output))
  File "/usr/lib/python3/dist-packages/picamera2/picamera2.py", line 1597, in start_recording
    self.start_encoder(encoder, output, pts=pts, quality=quality, name=name)
  File "/usr/lib/python3/dist-packages/picamera2/picamera2.py", line 1522, in start_encoder
    min_frame_duration = self.camera_ctrl_info["FrameDurationLimits"][1].min
KeyError: 'FrameDurationLimits'

Hardware :
Pi 3B+ Glamor enabled Bullseye 64

Dominant language: Python
Stars: 1.2k
Forks: 258
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