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docPhil99 / video_loop_back.md
Last active February 9, 2023 16:35
How to pass video to a dummy webcam.
  1. Start the v4l2loopback module:
sudo modprobe v4l2loopback \
      devices=1 exclusive_caps=1 video_nr=5 card_label="Dummy Camera"
  1. I have a short test video call Speed1.avi, this can be played streamed to /dev/video5 with ffmpeg -re -stream_loop -1 -i Speed1.avi -vcodec rawvideo -pix_fmt yuv420p -f v4l2 /dev/video5
@docPhil99
docPhil99 / testing_tensorflow_keras.md
Created December 7, 2020 15:26
Code for testing a custom layer in tensorflow 2 Keras

A simple example of code for testing a custom tensorflow Keras layer

    def my_init(shape, dtype=None):
        """This function is a custom kernel initialiser. It loads the weights from a matlab file. Adapt as need"""
        matlab = io.loadmat('../matlab/weights.mat')
        wfilter = matlab['wfilter']
        if shape != wfilter.shape:
            raise Exception('Shaped do not match')
        return tf.constant(wfilter, dtype=dtype)
@docPhil99
docPhil99 / python_docker.md
Last active October 16, 2020 13:41

This is running on Linux Mint 20

  • Install docker.

    • sudo apt-get -y install apt-transport-https ca-certificates curl software-properties-common

    • curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -

    • sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(. /etc/os-release; echo "$UBUNTU_CODENAME") stable"

    • sudo apt-get update

    • sudo apt install docker-ce docker-compose

    • sudo usermod -aG docker $USER

  • and test with docker --version
@docPhil99
docPhil99 / controlling_ha.md
Last active March 7, 2023 17:12
Controlling Home Assistant remotely via curl

It's actually fairly easy to control Home Assistant remotely using curl but I couldn't find a complete solution on how to do this, so here goes...

  1. Activate the api in configuration.yaml by adding the line api:
  2. Get an Authorization token from HA (It's a Long-Lived Access Tokens which can be created on your HA user profile page)
  3. This list of exposed states can be found using curl -X GET -H "Authorization: Bearer YOUR_TOKEN" -H "Content-Type: application/json" http://YOUR_IP:8123/api/states | prettyjson
  • Note prettyjson is an alias for python -m json.tool, you don't need this it's just easier to read.
  1. To get the state of a device append the entity.id to the URL, eg curl -X GET -H "Authorization: Bearer YOUR_TOKEN" -H "Content-Type: application/json" http://YOUR_IP:8123/api/states/switch.mylight | prettyjson
  2. The API documentation shows you how to change the states but this does not actually turn on the lights, etc. Instead, us
@docPhil99
docPhil99 / igtv_bars.md
Last active March 29, 2021 12:51
Add bars to video for IGTV

To convert a video to 16x9 or 9x16 by adding black bars use ffmpeg as follows ffmpeg -i film1.mp4 -vf "scale=1920:1080:force_original_aspect_ratio=decrease,pad=1920:1080:(ow-iw)/2:(oh-ih)/2,setsar=1" film1_bars.mp4

This add bars to the top and bottom, flip both of the 1920:1080 to 1080:1920 for horizontal bars (better for computer monitors, TV etc)

Note IGTV also requires h.264 and a max of 30fps.

Thanks to https://stackoverflow.com/a/46693766/3361398

@docPhil99
docPhil99 / ffmpeg.md
Last active July 24, 2020 10:12
Some useful command in ffmpeg

Speed

  • ffmpeg -i input.mkv -filter:v "setpts=0.5*PTS" output.mkv increases doubles playback speed, by dropping frames see

Playback

  • ffmpeg -i input.mp4 -f opengl "window title" or use ffplay

Convertion

  • ffmpeg -i video.flv video.mpeg
@docPhil99
docPhil99 / arg_parse_demo.py
Last active November 1, 2023 20:20
Simple demo of argparse in python
"""Simple demo of argparse in python, see http://zetcode.com/python/argparse/"""
import argparse
parser = argparse.ArgumentParser()
parser.add_argument('name') # positional argument, note no dash!
parser.add_argument('-n', type=int, required=True, help="the number") # Required argument, must be a int, eg. -n 4
parser.add_argument('-e', type=int, default=2, help="defines the value") # Optional argument with a default
parser.add_argument('-o', '--output', action='store_true', help="shows output") # a binary flag
@docPhil99
docPhil99 / git_cheat_sheet.md
Last active March 2, 2020 16:27
Some useful notes on git

Split directory into a new repo

  • clone the repo into a new directory
  • cd into it
  • git filter-branch --prune-empty --subdirectory-filter FOLDER-NAME BRANCH-NAME
    • where:
    • FOLDER-NAME: The folder within your project that you'd like to create a separate repository from.
    • BRANCH-NAME: The default branch for your current project, for example, master.
  • Update the remote git remote set-url origin https://github.com/USERNAME/NEW-REPOSITORY-NAME.git
  • Verify git remote -v
  • Push the changes git push -u origin BRANCH-NAME
@docPhil99
docPhil99 / opencv_qt_label.md
Last active April 13, 2024 15:48
How to display opencv video in pyqt apps

The code for this tutorial is here

Opencv provides are useful, but limited, method of building a GUI. A much more complete system could be acheived using pyqt. The question is, how do we display images. There are quite a few possible routes but perhaps the easiest is to use QLabel since it has a setPixmap function. Below is some code that creates two labels. It then creates a grey pixmap and displays it one of the labels. code: staticLabel1.py

from PyQt5.QtWidgets import QWidget, QApplication, QLabel, QVBoxLayout
from PyQt5.QtGui import QPixmap, QColor
import sys
@docPhil99
docPhil99 / Useful_datasets_and_websites.md
Last active June 21, 2019 18:32
Dataset List