How to get video frames from UVC device in MJPG format on ARM64 system? (with python)

0

As the title. I want to get the highest performance from Logic HD Pro Webcam C920, which should be 1920*1080, FPS=30.0. I've tried many ways from Internet, however, neither could solve my problem. Generally, There are two methods could achieve the goal.

  1. opencv-python -> VideoCapture:

Here is my code.

    cap = cv2.VideoCapture('/dev/video0')
    cap.set(cv2.CAP_PROP_FOURCC, cv2.VideoWriter_fourcc(*'MJPG'))
    cap.set(cv2.CAP_PROP_FRAME_WIDTH, 1920)
    cap.set(cv2.CAP_PROP_FRAME_HEIGHT, 1080)

The problem is although I set the correct resolution and format which is supported by camera and computer, I still get the wrong FPS from camera (Result is 1920*1080 FPS=5). The camera I used is Logic HD Pro Webcam C920. Below are the camera information.

        Index       : 0
        Type        : Video Capture
        Pixel Format: 'YUYV'
        Name        : YUYV 4:2:2
                Size: Discrete 640x480
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 160x90
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 160x120
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 176x144
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 320x180
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 320x240
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 352x288
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 432x240
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 640x360
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 800x448
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 800x600
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 864x480
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 960x720
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 1024x576
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 1280x720
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 1600x896
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 1920x1080
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 2304x1296
                        Interval: Discrete 0.500s (2.000 fps)
                Size: Discrete 2304x1536
                        Interval: Discrete 0.500s (2.000 fps)

        Index       : 2
        Type        : Video Capture
        Pixel Format: 'MJPG' (compressed)
        Name        : Motion-JPEG
                Size: Discrete 640x480
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 160x90
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 160x120
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 176x144
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 320x180
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 320x240
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 352x288
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 432x240
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 640x360
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 800x448
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 800x600
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 864x480
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 960x720
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 1024x576
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 1280x720
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 1600x896
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
                Size: Discrete 1920x1080
                        Interval: Discrete 0.033s (30.000 fps)
                        Interval: Discrete 0.042s (24.000 fps)
                        Interval: Discrete 0.050s (20.000 fps)
                        Interval: Discrete 0.067s (15.000 fps)
                        Interval: Discrete 0.100s (10.000 fps)
                        Interval: Discrete 0.133s (7.500 fps)
                        Interval: Discrete 0.200s (5.000 fps)
Factory Details:
  Rank                     primary (256)
  Long-name                Video (video4linux2) Source
  Klass                    Source/Video
  Description              Reads frames from a Video4Linux2 device
  Author                   Edgard Lima <edgard.lima@gmail.com>, Stefan Kost <ensonic@users.sf.net>

Plugin Details:
  Name                     video4linux2
  Description              elements for Video 4 Linux
  Filename                 /usr/lib/aarch64-linux-gnu/gstreamer-1.0/libgstvideo4linux2.so
  Version                  1.14.5
  License                  LGPL
  Source module            gst-plugins-good
  Source release date      2019-05-29
  Binary package           GStreamer Good Plugins (Ubuntu)
  Origin URL               https://launchpad.net/distros/ubuntu/+source/gst-plugins-good1.0

GObject
 +----GInitiallyUnowned
       +----GstObject
             +----GstElement
                   +----GstBaseSrc
                         +----GstPushSrc
                               +----GstV4l2Src

Implemented Interfaces:
  GstURIHandler
  GstTuner
  GstColorBalance
  GstVideoOrientation

Pad Templates:
  SRC template: 'src'
    Availability: Always
    Capabilities:
      image/jpeg
      video/mpeg
            mpegversion: 4
           systemstream: false
      video/mpeg
            mpegversion: 2
      video/mpegts
           systemstream: true
      video/x-bayer
                 format: { (string)bggr, (string)gbrg, (string)grbg, (string)rggb }
                  width: [ 1, 32768 ]
                 height: [ 1, 32768 ]
              framerate: [ 0/1, 2147483647/1 ]
      video/x-dv
           systemstream: true
      video/x-h263
                variant: itu
      video/x-h264
          stream-format: { (string)byte-stream, (string)avc }
              alignment: au
      video/x-pwc1
                  width: [ 1, 32768 ]
                 height: [ 1, 32768 ]
              framerate: [ 0/1, 2147483647/1 ]
      video/x-pwc2
                  width: [ 1, 32768 ]
                 height: [ 1, 32768 ]
              framerate: [ 0/1, 2147483647/1 ]
      video/x-raw
                 format: { (string)RGB16, (string)BGR, (string)RGB, (string)GRAY8, (string)GRAY16_LE, (string)GRAY16_BE, (string)YVU9, (string)YV12, (string)YUY2, (string)YVYU, (string)UYVY, (string)Y42B, (string)Y41B, (string)YUV9, (string)NV12_64Z32, (string)NV24, (string)NV61, (string)NV16, (string)NV21, (string)NV12, (string)I420, (string)BGRA, (string)BGRx, (string)ARGB, (string)xRGB, (string)BGR15, (string)RGB15 }
                  width: [ 1, 32768 ]
                 height: [ 1, 32768 ]
              framerate: [ 0/1, 2147483647/1 ]
      video/x-sonix
                  width: [ 1, 32768 ]
                 height: [ 1, 32768 ]
              framerate: [ 0/1, 2147483647/1 ]
      video/x-vp8
      video/x-vp9
      video/x-wmv
             wmvversion: 3
                 format: WVC1

Element has no clocking capabilities.

URI handling capabilities:
  Element can act as source.
  Supported URI protocols:
    v4l2

Pads:
  SRC: 'src'
    Pad Template: 'src'

Element Properties:
  name                : The name of the object
                        flags: readable, writable
                        String. Default: "v4l2src0"
  parent              : The parent of the object
                        flags: readable, writable
                        Object of type "GstObject"
  blocksize           : Size in bytes to read per buffer (-1 = default)
                        flags: readable, writable
                        Unsigned Integer. Range: 0 - 4294967295 Default: 4096
  num-buffers         : Number of buffers to output before sending EOS (-1 = unlimited)
                        flags: readable, writable
                        Integer. Range: -1 - 2147483647 Default: -1
  typefind            : Run typefind before negotiating (deprecated, non-functional)
                        flags: readable, writable, deprecated
                        Boolean. Default: false
  do-timestamp        : Apply current stream time to buffers
                        flags: readable, writable
                        Boolean. Default: false
  device              : Device location
                        flags: readable, writable
                        String. Default: "/dev/video0"
  device-name         : Name of the device
                        flags: readable
                        String. Default: null
  device-fd           : File descriptor of the device
                        flags: readable
                        Integer. Range: -1 - 2147483647 Default: -1
  flags               : Device type flags
                        flags: readable
                        Flags "GstV4l2DeviceTypeFlags" Default: 0x00000000, "(none)"
                           (0x00000001): capture          - Device supports video capture
                           (0x00000002): output           - Device supports video playback
                           (0x00000004): overlay          - Device supports video overlay
                           (0x00000010): vbi-capture      - Device supports the VBI capture
                           (0x00000020): vbi-output       - Device supports the VBI output
                           (0x00010000): tuner            - Device has a tuner or modulator
                           (0x00020000): audio            - Device has audio inputs or outputs
  brightness          : Picture brightness, or more precisely, the black level
                        flags: readable, writable, controllable
                        Integer. Range: -2147483648 - 2147483647 Default: 0
  contrast            : Picture contrast or luma gain
                        flags: readable, writable, controllable
                        Integer. Range: -2147483648 - 2147483647 Default: 0
  saturation          : Picture color saturation or chroma gain
                        flags: readable, writable, controllable
                        Integer. Range: -2147483648 - 2147483647 Default: 0
  hue                 : Hue or color balance
                        flags: readable, writable, controllable
                        Integer. Range: -2147483648 - 2147483647 Default: 0
  norm                : video standard
                        flags: readable, writable
                        Enum "V4L2_TV_norms" Default: 0, "none"
                           (0): none             - none
                           (45056): NTSC             - NTSC
                           (4096): NTSC-M           - NTSC-M
                           (8192): NTSC-M-JP        - NTSC-M-JP
                           (32768): NTSC-M-KR        - NTSC-M-KR
                           (16384): NTSC-443         - NTSC-443
                           (255): PAL              - PAL
                           (7): PAL-BG           - PAL-BG
                           (1): PAL-B            - PAL-B
                           (2): PAL-B1           - PAL-B1
                           (4): PAL-G            - PAL-G
                           (8): PAL-H            - PAL-H
                           (16): PAL-I            - PAL-I
                           (224): PAL-DK           - PAL-DK
                           (32): PAL-D            - PAL-D
                           (64): PAL-D1           - PAL-D1
                           (128): PAL-K            - PAL-K
                           (256): PAL-M            - PAL-M
                           (512): PAL-N            - PAL-N
                           (1024): PAL-Nc           - PAL-Nc
                           (2048): PAL-60           - PAL-60
                           (16711680): SECAM            - SECAM
                           (65536): SECAM-B          - SECAM-B
                           (262144): SECAM-G          - SECAM-G
                           (524288): SECAM-H          - SECAM-H
                           (3276800): SECAM-DK         - SECAM-DK
                           (131072): SECAM-D          - SECAM-D
                           (1048576): SECAM-K          - SECAM-K
                           (2097152): SECAM-K1         - SECAM-K1
                           (4194304): SECAM-L          - SECAM-L
                           (8388608): SECAM-Lc         - SECAM-Lc
  io-mode             : I/O mode
                        flags: readable, writable
                        Enum "GstV4l2IOMode" Default: 0, "auto"
                           (0): auto             - GST_V4L2_IO_AUTO
                           (1): rw               - GST_V4L2_IO_RW
                           (2): mmap             - GST_V4L2_IO_MMAP
                           (3): userptr          - GST_V4L2_IO_USERPTR
                           (4): dmabuf           - GST_V4L2_IO_DMABUF
                           (5): dmabuf-import    - GST_V4L2_IO_DMABUF_IMPORT
  extra-controls      : Extra v4l2 controls (CIDs) for the device
                        flags: readable, writable
                        Boxed pointer of type "GstStructure"
  pixel-aspect-ratio  : Overwrite the pixel aspect ratio of the device
                        flags: readable, writable
                        String. Default: null
  force-aspect-ratio  : When enabled, the pixel aspect ratio will be enforced
                        flags: readable, writable
                        Boolean. Default: true

Element Signals:
  "prepare-format" :  void user_function (GstElement* object,
                                          gint arg0,
                                          GstCaps* arg1,
                                          gpointer user_data);
  1. Gstreamer

Here is my code and it doesn't work, either. Unless remove the pixelformat, and set width=2304,height=1536,framerate=2/1

        gst_str =  'v4l2src device=/dev/video0 ! '
                   'video/x-raw, pixelformat=2, width=1920, height=1080, framerate=30/1 ! '
                   'videoconvert ! appsink'
        cap = cv2.VideoCapture(gst_str, cv2.CAP_GSTREAMER)

This has already perplexed me for a long time. I really wonder how to get the correct resolution, fps and format from UVC device. I'll very very very appreciate it if someone could solve the problem and told me what's going on.

python
linux
opencv
gstreamer
uvc
asked on Stack Overflow Nov 30, 2020 by Player Best

0 Answers

Nobody has answered this question yet.


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