My Notebook

Foxdie included in category General and series sticky-post

2021-11-21 2023-02-26 2339 words 11 minutes

This is my online notebook, where I keep various pieces of information for reference purposes.

Series - sticky-post

Notice

The below post is original from my VuePress Notebook

Notice

You can visit this address https://blog.pquan.info or https://foxdie.one for even faster-loading speed of this website.

1 WEBP

https://developers.google.com/speed/webp

The bin/ directory contains tools for encoding (cwebp.exe) and decoding (dwebp.exe) images.

The easiest use should look like:

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  cwebp input.png -q 80 -o output.webp

which will convert the input file to a WebP file using a quality factor of 80 on a 0 -> 100 scale (0 being the lowest quality, 100 being the best. Default value is 75). You might want to try the -lossless flag too, which will compress the source (in RGBA format) without any loss. The -q quality parameter will in this case control the amount of processing time spent trying to make the output file as small as possible.

If you also want to resize the image, use parameter -resize width height Resize the source to a rectangle with size width x height. If either (but not both) of the width or height parameters is 0, the value will be calculated preserving the aspect-ratio. Note: scaling is applied after cropping.

Example:

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  cwebp input.png -q 80 -resize 1920 0 -o output.webp

2 WEBM

how-to-create-a-webm-video-file

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ffmpeg -i input.mp4 -c:v libvpx -crf 10 -b:v 1M -c:a libvorbis output.webm

By default the CRF value can be from 4–63, and 10 is a good starting point. Lower values mean better quality.

▨ Trim Videos with ffmpeg:

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ffmpeg -i input.mp4 -ss hh:mm:ss(1) -to hh:mm:ss(2) -c:v libvpx -crf 10 -b:v 1M -c:a libvorbis output.webm

-ss: It defines the start of the section that you want to trim.
hh:mm:ss(1): This concrete point (start time) can be sought from the input file.
-to: It’s the end of the section that you want to trim.
hh:mm:ss(2): This specific point (end time) can be sought from the input file.

If you only want to trim the video, use copy parameter. The command’s copy part is intended to copy both the original audio and video content without re-encoding:

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ffmpeg -i input.mp4 -ss hh:mm:ss(1) -to hh:mm:ss(2) -c:v copy -c:a copy output.mp4

Sometimes you may want to crop the video:

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ffmpeg -i input.mp4 output2.mp4 -vf crop=1920:1080:0:200 output.mp4

-vf is the command for video filter, or can be typed as -filter:v.
crop=1920:1080:0:200 means to make a 1920×1080 video starting from the leftmost side of the source image (=0 pixels horizontally) and 200 pixels down from the top.

▨ Use cmder for better experience.

3 Markdown guide

Go to

3.1 Links:

Text in [] and URL goes in ()

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[text](URL)
My favorite search engine is [Duck Duck Go](https://duckduckgo.com).

Result: Duck Duck Go.

Text in [] and URL goes in (), text in this case can’t have blank space.

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[cmder](https://pquan.info/cmder-thay-the-hieu-qua-cho-command-promp-tren-windows)

Result: cmder

Reference-style Links: are a special kind of link that make URLs easier to display and read in Markdown, keep the text easy to read.

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In a hole in the ground there lived a hobbit. Not a nasty, dirty, wet hole, filled with the ends
of worms and an oozy smell, nor yet a dry, bare, sandy hole with nothing in it to sit down on or to eat: it was a [hobbit-hole][1], and that means comfort.
[1]: <https://en.wikipedia.org/wiki/Hobbit#Lifestyle> "Hobbit lifestyles" (ref link)

the rendered output:

In a hole in the ground there lived a hobbit. Not a nasty, dirty, wet hole, filled with the ends of worms and an oozy smell, nor yet a dry, bare, sandy hole with nothing in it to sit down on or to eat: it was a [hobbit-hole][1], and that means comfort. [1]:https://en.wikipedia.org/wiki/Hobbit#Lifestyle “Hobbit lifestyles”

(ref link doesn’t work?)

Align Image in Markdown

4 Math and Formula

https://imronuke.wordpress.com/2012/02/17/how-to-convert-equation-in-mathtype-to-latex/

https://tex.stackexchange.com/questions/233963/convert-mathtype-and-ms-word-equations-equations-to-latex

~~https://github.com/maginapp/vuepress-plugin-katex~~

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plugins: {
        '@maginapp/katex': {
          delimiters: 'dollars'
        }
    },

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$\Gamma(n) = (n-1)!\quad\forall n\in\mathbb N$

Euler's identity $e^{i\pi}+1=0$ is a beautiful formula in $\mathbb{R}^2$.

Supposing that $y >= 0$ and that $[\log x]$ represents the integer part of $\log x$, let:

$$\Phi (y) = \frac {1} {2 \pi i} \int_{2 - i \infty}^{2 + i \infty} \frac {y^{\omega} \mathrm{d} \omega} {\omega \left(1 + \frac {\omega} {(\log x)^{1.1}}\right)^{[ \log x ] + 1}}, x > 1$$

Obviously, when $0 <= y <= 1$, there is $\Phi(y) = 0$. For all $y >= 0$, $\Phi(y)$ is a non-decreasing function.

When $\log x>=10^4$ and $y>= e^{2{(\log x)}^{-0.1}}$, thus:

$$1 - x^{- 0.1} <= \Phi (y) <= 1$$

$$\Phi (y) = \frac {1} {2 \pi i}$$

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\(Gamma(n) = (n-1)!\quad\forall n\in\mathbb N\)

Euler's identity \(e^{i\pi}+1=0\) is a beautiful formula in \(\mathbb{R}^2\).

Supposing that \(y >= 0\) and that \([\log x]\) represents the integer part of $\log x\), let:

\[\Phi (y) = \frac {1} {2 \pi i} \int_{2 - i \infty}^{2 + i \infty} \frac {y^{\omega} \mathrm{d} \omega} {\omega \left(1 + \frac {\omega} {(\log x)^{1.1}}\right)^{[ \log x ] + 1}}, x > 1\]

Obviously, when \(0 <= y <= 1\), there is \(\Phi(y) = 0\). For all \(y >= 0\), \(\Phi(y)\) is a non-decreasing function.

When \(\log x>=10^4\) and \(y>= e^{2{(\log x)}^{-0.1}}\), thus:

\[1 - x^{- 0.1} <= \Phi (y) <= 1\]

$\Gamma(n) = (n-1)!\quad\forall n\in\mathbb N$

Euler’s identity $e^{i\pi}+1=0$ is a beautiful formula in $\mathbb{R}^2$.

Supposing that $y >= 0$ and that $[\log x]$ represents the integer part of $\log x$, let:

$$\Phi (y) = \frac {1} {2 \pi i} \int_{2 - i \infty}^{2 + i \infty} \frac {y^{\omega} \mathrm{d} \omega} {\omega \left(1 + \frac {\omega} {(\log x)^{1.1}}\right)^{[ \log x ] + 1}}, x > 1$$

Obviously, when $0 <= y <= 1$, there is $\Phi(y) = 0$. For all $y >= 0$, $\Phi(y)$ is a non-decreasing function.

When $\log x>=10^4$ and $y>= e^{2{(\log x)}^{-0.1}}$, thus:

$$1 - x^{- 0.1} <= \Phi (y) <= 1$$

~~Supported Functions: https://katex.org~~

Note: There is problem with bracket { } when convert MathType form MS Word to LaTeX 2.09. If too many { } brackets than necessary, npm run build will fail with errors. Since KaTeX seems to require less { } in formula. Solution is that manually deleting redundant { } brackets after conversion will work, but if there are so many math formula in document then it’ll become a boring chore. => need a more refined answer to this hurdle (some tool maybe, or a fine LaTeX/MathJax plugin).

As for now, since I has some problem with KaTeX plugin (can’t make it work anymore), switch back to MathJax: => It also allows quickly copy converted MathType formula to .md file without editing { }.

https://vuepress-community.netlify.app/en/plugins/mathjax/

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plugins: [
[
  'vuepress-plugin-mathjax',
  {
    target: 'svg',
    macros: {
      '*': '\\times',
    },
  },
], ['aplayer']],
}

5 Nginx

See Install Nginx on CentOS 8

6 Photoshop and Krita

I’m using Krita as a light weight Image Editor, portable-app ready. I’m still using Photoshop but if my machine I’m working on doesn’t have it installed, then I should just grab a portable Krita for a quick edit.

BTW, if you are a Photoshop user (like me) and you’re looking for Eraser, then check Krita’s manual:

In Krita, the eraser is not its own tool; it is a Blending mode (or Composite mode). You can toggle between erase mode and paint mode by pressing the E key, individually for each of your brushes.

7 SSH

As SSH is built in with Cmder, you may use it anytime by typing: ssh @ip [-p port]

Here is an example: ssh user@10.0.0.8 -p8888

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ssh user@10.0.0.8 -p8888

8 Cmder

Unable to cd to another drive? Try D: if cd D: doesn’t work.

https://github.com/cmderdev/cmder/issues/6

9 Rclone

How to transfer files that marked as abused

You can use --drive-acknowledge-abuse option:

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rclone sync -P A: B: --drive-acknowledge-abuse --exclude "/some_folder/**"

--drive-shared-with-me:

Only show files that are shared with me.

Instructs rclone to operate on your “Shared with me” folder (where Google Drive lets you access the files and folders others have shared with you).

This works both with the “list” (lsd, lsl, etc.) and the “copy” commands (copy, sync, etc.), and with all other commands too.

Example:

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rclone lsd "mydrive:" --drive-shared-with-me
#   -1 2022-03-03 11:53:46        -1 Midas Civil
#   -1 2021-09-02 14:13:01        -1 PHAN MEM
rclone lsd "mydrive:\PHAN MEM" --drive-shared-with-me
#   -1 2021-09-15 08:57:43        -1 CAMTASIA
#   -1 2021-09-15 08:58:35        -1 CIVIL 3D
#   -1 2021-09-15 15:02:31        -1 INFRAWORK 2020

10 Yarn

Restore registry: https://stackoverflow.com/questions/49048013/yarn-keeps-using-old-registry

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rm ~/.config/yarn/global/yarn.lock

yarn config set registry https://registry.yarnpkg.com/

11 Youtube

Under Tides BGM

11.1 Programming channels

Free Code Camp

Edureka

Kalle Hallden

11.2 YouTube Creators

Video Chapters

To add your own video chapters:

Sign in to YouTube Studio.
From the left menu, select Content.
Click the video that you’d like to edit.
In the Description, add a list of timestamps and titles.
Make sure that the first timestamp you list starts with 00:00.
Your video should have at least three timestamps listed in ascending order.
he minimum length for video chapters is 10 seconds.

Example:

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- Introduction 00:00
- Kjerag Guidebook 00:26  
- Obtain Kjera 01:19  
- Turicum Trade Zone 04:22  
- The Medal Set 09:36  

Video Guide: How to Add Chapters to Your Videos Using Timestamps

11.3 Youtube-DL

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youtube-dl -f best [URL] --fixup --prefer-ffmpeg --ffmpeg-location C:\cmder\bin

◈ There is a youtube-dl fork with additional features and fixes, that is called yt-dlp. See here for its available command and options:

https://github.com/yt-dlp/yt-dlp#general-options

11.3.1 Common usage and options:

◈ By default, yt-dlp tries to download the best available quality if you don’t pass any options:

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yt-dlp [URL] --ffmpeg-location C:\cmder\bin

◈ Download the best video available with the largest resolution but no better than 1080p, or the best video with the smallest resolution if there is no video under 1080p:

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yt-dlp -S res:1080 [URL] --ffmpeg-location C:\cmder\bin

◈ --hls-use-mpegts is enabled by default for live streams

◈ Extract audio from Youtube link only:

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yt-dlp [URL] --extract-audio --audio-format best

Audio format: Format to convert the audio to when -x (--extract-audio) is used. (currently supported: best (default), mp3, aac, m4a, opus, vorbis, flac, alac, wav).

Tip

yt-dlp works well with Bilibili video links too.
If you don’t want to use CLI, then there is a GUI for yt-dlp or youtube-dl.

12 Obsidian.md

https://obsidian.md

The human brain is non-linear: we jump from idea to idea, all the time. Your second brain should work the same.

In Obsidian, making and following connections is frictionless. Tend to your notes like a gardener; at the end of the day, sit back and marvel at your own knowledge graph.

13 Visual Studio Code

Release Notes: https://code.visualstudio.com/updates

In Visual Studio Code, just open the Command Palette (Ctrl+Shift+P on Windows/Linux, CMD+Shift+P on macOs), type Show Release Notes, then hit Enter.

The release notes will be displayed on the same tab.

It is also available from the Help menu > Release Notes.

14 Python

14.1 Pycharm

Pycharm gets error “can’t find '__main__' module”?

The way I got around is that in the configuration window:

Leave the script path empty.
Add the path to the script’s directory in the working directory.
In the parameters, add $FileName$

This will automatically pick your file and run it.

14.2 Python tutorials

Python Tutorial: Web Scraping with Requests-HTML

Python Tutorial: Web Scraping with BeautifulSoup and Requests

https://code.visualstudio.com/docs/python/tutorial-django

https://pythondocs.xyz

Web search interface for Python’s documentation

Python Algorithms

90 Python Examples

Break The Ice With Python

More Python Examples

15 Midas Civil

15.1 Guides

Elite Training Series Session 1 Steel Composite I Girder Bridge

https://www.youtube.com/watch?v=s3JF99CDI-4

Elite Training Series Session 2 Frame Culvert Bridge

https://www.youtube.com/watch?v=UVSR9EEWxjk

Download the Training Materials

https://www.mediafire.com/folder/os5z1cfczthv8/MIDAS

15.2 Issues

[Error] Boundary condition has not been defined:

The support nodes were not assigned to any structure group. Hence, these nodes and the boundaries which need these nodes are not activated in the construction stage. Kindly add all the support nodes to any structure group activated in the first construction stage. Once this is done, the model is analyzed as expected.

16 Mechanical and civil engineering concepts

The Efficient Engineer Channel:

https://www.youtube.com/c/TheEfficientEngineer/videos

17 Vue.Js

Vue JS Crash Course 2021: https://www.youtube.com/watch?v=qZXt1Aom3Cs

Vue.js Developers Blog: https://vuejsdevelopers.com/topics/vue-js/

18 Github

18.1 GitHub Desktop

GitHub Desktop won’t open on Windows 10. When double clicking on the shortcut nothing happens. GitHub Desktop don’t show in the Task Manager > Processes but shows in the Task Manager > Details

Solution: Go to C:\Users\YOUR USER NAMEn\AppData\Local\GitHubDesktop, and then delete the most recent app-.

19 Unsorted lists:

Down here is my unsorted lists for anything catching my eyes: (will be sorted into proper categories eventually)

Thank Suisei Archive Guide for bringing me the joyful adventure of Vue.Js and VuePress -> I have started creating this blog not so long after I visited that site and love it. ❤️ Although I’m not even interested in Hololive 😂

https://www.bookstack.cn/read/vuepress2-en/41c7610565ee1a40.md

https://www.reddit.com/r/vuejs/comments/qge221/what_backend_to_use_for_vue/

https://dev.to/frontendfoxes/build-a-beautiful-website-with-vuepress-and-tailwindcss--3a03

https://github.com/HEIGE-PCloud/DoIt

https://aozaki.cc

🎶 https://hikarinoakari.com 🎶

🎶 monster-siren.hypergryph.com/music 🎶

https://mrfz.fandom.com/wiki/Requiem#Romanized 🎵

Bridge Technology Series: Improving Inspection Access at Segmental Bridge Abutments

https://www.udemy.com/course/practical-regex

https://web.archive.org/save => save an archive of webpage, just in case it’s 404 in the future.

https://www.researchgate.net/figure/Hognestad-Parabola-30_fig10_40540797

https://gofile.io/welcome

Zalgo Text

https://www.lightgalleryjs.com/docs/vue/

List of VTuber-related software and resources

https://xbeibeix.com/api/bilibili Website for downloading HD video from Bilibili.

https://mirror.codebucket.de: Codebucket Webmirror (powered by h5ai)

https://larsjung.de/h5ai: modern HTTP web server index

https://anibrain.ai: An anime/manga recommender system with machine learning techniques focused on innate features (e.g. plot) to determine similarity and make recommendations

https://developers.google.com/search/docs/advanced/javascript/javascript-seo-basics

https://abseil.io/docs/python (Python Guides)

https://devdocs.io

https://github.com/magic-akari/lrc-maker: An online tool which helps you create your lrc file.

https://realfavicongenerator.net: For generating your favicons.

Yandex OCR: To translate text from photos and images.

taylantatli.github.io/Moon/: Moon is a minimal, one column Jekyll theme.

Quillbot: QuillBot was created as a full-sentence thesaurus to help students and professionals write more confidently and quickly.

https://openai.com/blog/chatgpt/

https://camas.unddit.com: Search reddit using the pushshift.io API, can search by username and subreddit.

Contents

My Notebook

1 WEBP

2 WEBM

3 Markdown guide

3.1 Links:

4 Math and Formula

5 Nginx

6 Photoshop and Krita

7 SSH

8 Cmder

9 Rclone

10 Yarn

11 Youtube

11.1 Programming channels

11.2 YouTube Creators

11.3 Youtube-DL

11.3.1 Common usage and options:

12 Obsidian.md

13 Visual Studio Code

14 Python

14.1 Pycharm

14.2 Python tutorials

15 Midas Civil

15.1 Guides

15.2 Issues

16 Mechanical and civil engineering concepts

17 Vue.Js

18 Github

18.1 GitHub Desktop

19 Unsorted lists: