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Rennes Emotion Map 2010-11
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Frames took with ELP camera has unknown pixel format at FHD ?
11 novembre 2024, par Marcel KoperaI'm trying to take a one frame ever x seconds from my usb camera. Name of the camera is : ELP-USBFHD06H-SFV(5-50).
Code is not 100% done yet, but I'm using it this way right now ↓ (
shot
fn is called frommain.py
in a loop)


import cv2
import subprocess

from time import sleep
from collections import namedtuple

from errors import *

class Camera:
 def __init__(self, cam_index, res_width, res_height, pic_format, day_time_exposure_ms, night_time_exposure_ms):
 Resolution = namedtuple("resolution", ["width", "height"])
 self.manual_mode(True)

 self.cam_index = cam_index
 self.camera_resolution = Resolution(res_width, res_height)
 self.picture_format = pic_format
 self.day_time_exposure_ms = day_time_exposure_ms
 self.night_time_exposure_ms = night_time_exposure_ms

 self.started: bool = False
 self.night_mode = False

 self.cap = cv2.VideoCapture(self.cam_index, cv2.CAP_V4L2)
 self.cap.set(cv2.CAP_PROP_FRAME_WIDTH, self.camera_resolution.width)
 self.cap.set(cv2.CAP_PROP_FRAME_HEIGHT, self.camera_resolution.height)
 self.cap.set(cv2.CAP_PROP_FOURCC, cv2.VideoWriter_fourcc(*self.picture_format))

 

 def start(self):
 sleep(1)
 if not self.cap.isOpened():
 return CameraCupError()

 self.set_exposure_time(self.day_time_exposure_ms)
 self.set_brightness(0)
 sleep(0.1)
 
 self.started = True



 def shot(self, picture_name, is_night):
 if not self.started:
 return InitializationError()

 self.configure_mode(is_night)

 # Clear buffer
 for _ in range(5):
 ret, _ = self.cap.read()

 ret, frame = self.cap.read()

 sleep(0.1)

 if ret:
 print(picture_name)
 cv2.imwrite(picture_name, frame)
 return True

 else:
 print("No photo")
 return False


 
 def release(self):
 self.set_exposure_time(156)
 self.set_brightness(0)
 self.manual_mode(False)
 self.cap.release()



 def manual_mode(self, switch: bool):
 if switch:
 subprocess.run(["v4l2-ctl", "--set-ctrl=auto_exposure=1"])
 else:
 subprocess.run(["v4l2-ctl", "--set-ctrl=auto_exposure=3"])
 sleep(1)

 
 
 def configure_mode(self, is_night):
 if is_night == self.night_mode:
 return

 if is_night:
 self.night_mode = is_night
 self.set_exposure_time(self.night_time_exposure_ms)
 self.set_brightness(64)
 else:
 self.night_mode = is_night
 self.set_exposure_time(self.day_time_exposure_ms)
 self.set_brightness(0)
 sleep(0.1)



 def set_exposure_time(self, ms: int):
 ms = int(ms)
 default_val = 156

 if ms < 1 or ms > 5000:
 ms = default_val

 self.cap.set(cv2.CAP_PROP_EXPOSURE, ms)



 def set_brightness(self, value: int):
 value = int(value)
 default_val = 0

 if value < -64 or value > 64:
 value = default_val

 self.cap.set(cv2.CAP_PROP_BRIGHTNESS, value)



Here are settings for the camera (yaml file)


camera:
 camera_index: 0
 res_width: 1920
 res_height: 1080
 picture_format: "MJPG"
 day_time_exposure_ms: 5
 night_time_exposure_ms: 5000
 photos_format: "jpg"




I do some configs like set manual mode for the camera, change exposure/brightness and saving frame.
Also the camera is probably catching the frames to the buffer (it is not saving latest frame in real time : it's more laggish), so I have to clear buffer every time. like this


# Clear buffer from old frames
 for _ in range(5):
 ret, _ = self.cap.read()
 
 # Get a new frame
 ret, frame = self.cap.read()



What I really don't like, but I could find a better way (tldr : setting buffer for 1 frame doesn't work on my camera).


Frames saved this method looks good with 1920x1080 resolution. BUT when I try to run
ffmpeg
command to make a timelapse from savedjpg
file like this

ffmpeg -framerate 20 -pattern_type glob -i "*.jpg" -c:v libx264 output.mp4



I got an error like this one


[image2 @ 0x555609c45240] Could not open file : 08:59:20.jpg
[image2 @ 0x555609c45240] Could not find codec parameters for stream 0 (Video: mjpeg, none(bt470bg/unknown/unknown)): unspecified size
Consider increasing the value for the 'analyzeduration' (0) and 'probesize' (5000000) options
Input #0, image2, from '*.jpg':
 Duration: 00:00:00.05, start: 0.000000, bitrate: N/A
 Stream #0:0: Video: mjpeg, none(bt470bg/unknown/unknown), 20 fps, 20 tbr, 20 tbn
Output #0, mp4, to 'output.mp4':
Output file #0 does not contain any stream



Also when I try to copy the files from Linux to Windows I get some weird copy failing error and option to skip the picture. But even when I press the skip button, the picture is copied and can be opened. I'm not sure what is wrong with the format, but the camera is supporting MPEG at 1920x1080.


>>> v4l2-ctl --all

Driver Info:
 Driver name : uvcvideo
 Card type : H264 USB Camera: USB Camera
 Bus info : usb-xhci-hcd.1-1
 Driver version : 6.6.51
 Capabilities : 0x84a00001
 Video Capture
 Metadata Capture
 Streaming
 Extended Pix Format
 Device Capabilities
 Device Caps : 0x04200001
 Video Capture
 Streaming
 Extended Pix Format
Media Driver Info:
 Driver name : uvcvideo
 Model : H264 USB Camera: USB Camera
 Serial : 2020032801
 Bus info : usb-xhci-hcd.1-1
 Media version : 6.6.51
 Hardware revision: 0x00000100 (256)
 Driver version : 6.6.51
Interface Info:
 ID : 0x03000002
 Type : V4L Video
Entity Info:
 ID : 0x00000001 (1)
 Name : H264 USB Camera: USB Camera
 Function : V4L2 I/O
 Flags : default
 Pad 0x0100000d : 0: Sink
 Link 0x0200001a: from remote pad 0x1000010 of entity 'Extension 4' (Video Pixel Formatter): Data, Enabled, Immutable
Priority: 2
Video input : 0 (Camera 1: ok)
Format Video Capture:
 Width/Height : 1920/1080
 Pixel Format : 'MJPG' (Motion-JPEG)
 Field : None
 Bytes per Line : 0
 Size Image : 4147789
 Colorspace : sRGB
 Transfer Function : Default (maps to sRGB)
 YCbCr/HSV Encoding: Default (maps to ITU-R 601)
 Quantization : Default (maps to Full Range)
 Flags :
Crop Capability Video Capture:
 Bounds : Left 0, Top 0, Width 1920, Height 1080
 Default : Left 0, Top 0, Width 1920, Height 1080
 Pixel Aspect: 1/1
Selection Video Capture: crop_default, Left 0, Top 0, Width 1920, Height 1080, Flags:
Selection Video Capture: crop_bounds, Left 0, Top 0, Width 1920, Height 1080, Flags:
Streaming Parameters Video Capture:
 Capabilities : timeperframe
 Frames per second: 15.000 (15/1)
 Read buffers : 0

User Controls

 brightness 0x00980900 (int) : min=-64 max=64 step=1 default=0 value=64
 contrast 0x00980901 (int) : min=0 max=64 step=1 default=32 value=32
 saturation 0x00980902 (int) : min=0 max=128 step=1 default=56 value=56
 hue 0x00980903 (int) : min=-40 max=40 step=1 default=0 value=0
 white_balance_automatic 0x0098090c (bool) : default=1 value=1
 gamma 0x00980910 (int) : min=72 max=500 step=1 default=100 value=100
 gain 0x00980913 (int) : min=0 max=100 step=1 default=0 value=0
 power_line_frequency 0x00980918 (menu) : min=0 max=2 default=1 value=1 (50 Hz)
 0: Disabled
 1: 50 Hz
 2: 60 Hz
 white_balance_temperature 0x0098091a (int) : min=2800 max=6500 step=1 default=4600 value=4600 flags=inactive
 sharpness 0x0098091b (int) : min=0 max=6 step=1 default=3 value=3
 backlight_compensation 0x0098091c (int) : min=0 max=2 step=1 default=1 value=1

Camera Controls

 auto_exposure 0x009a0901 (menu) : min=0 max=3 default=3 value=1 (Manual Mode)
 1: Manual Mode
 3: Aperture Priority Mode
 exposure_time_absolute 0x009a0902 (int) : min=1 max=5000 step=1 default=156 value=5000
 exposure_dynamic_framerate 0x009a0903 (bool) : default=0 value=0



I also tried to save the picture using
ffmpeg
in a case something is not right withopencv
like this :

ffmpeg -f v4l2 -framerate 30 -video_size 1920x1080 -i /dev/video0 -c:v libx264 -preset fast -crf 23 -t 00:01:00 output.mp4




It is saving the picture but also changing its format


[video4linux2,v4l2 @ 0x555659ed92b0] The V4L2 driver changed the video from 1920x1080 to 800x600
[video4linux2,v4l2 @ 0x555659ed92b0] The driver changed the time per frame from 1/30 to 1/15



But the format looks right when set it back to FHD using
v4l2



>>> v4l2-ctl --device=/dev/video0 --set-fmt-video=width=1920,height=1080,pixelformat=MJPG
>>> v4l2-ctl --get-fmt-video

Format Video Capture:
 Width/Height : 1920/1080
 Pixel Format : 'MJPG' (Motion-JPEG)
 Field : None
 Bytes per Line : 0
 Size Image : 4147789
 Colorspace : sRGB
 Transfer Function : Default (maps to sRGB)
 YCbCr/HSV Encoding: Default (maps to ITU-R 601)
 Quantization : Default (maps to Full Range)
 Flags :



I'm not sure what could be wrong with the format/camera and I don't think I have enough information to figure it out.


I tried to use
ffmpeg
instead ofopencv
and also change a few settings inopencv's cup
config.

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