change formatting

input examples are now given as ```bash input $ARG1 ``` While outputs use md's '> ' sign as a quote.
2023-06-17 21:28:20 +02:00
parent 1ba3010b81
commit ba8026e0c3
102 changed files with 2388 additions and 3211 deletions
--- a/vision/ffmpeg.md
+++ b/vision/ffmpeg.md
@@ -14,18 +14,26 @@ The input file might be a device, such as a camera.

 Take the format as 'grab the x11 screen'.

-> ffmpeg -f x11grab -s [screensize] -i :0.0 out.mkv
+```bash
+ffmpeg -f x11grab -s [screensize] -i :0.0 out.mkv
+```

 Get screensize with

-> xrandr -q
+```bash
+xrandr -q
+```

 or maybe just...

-> ffmpeg -f x11grab -s "$(xdpyinfo | grep dimensions | awk '{print $2}')" -i :1.0 out.mkv
+```bash
+ffmpeg -f x11grab -s "$(xdpyinfo | grep dimensions | awk '{print $2}')" -i :1.0 out.mkv
+```

 #Add default pulse audio
-> ffmpeg -f x11grab -s [screensize] -i :0.0 -f alsa -i default out.mkv
+```bash
+ffmpeg -f x11grab -s [screensize] -i :0.0 -f alsa -i default out.mkv
+```

 For problems, see pavucontrol.

@@ -34,7 +42,9 @@ For problems, see pavucontrol.

 # Rotate

-> ffmpeg -i in.mov -vf "transpose=1" out.mov
+```bash
+ffmpeg -i in.mov -vf "transpose=1" out.mov
+```

 0 = 90 Counterclockwise and verfical flip (default)
 1 = 90 Clockwise
@@ -51,89 +61,106 @@ ffmpeg -i input.mp4 -vcodec libx264 -crf 20 output.mp4

 Check for supported formats:

-> ffmpeg -formats
+```bash
+ffmpeg -formats
+```

 To convert from mkv to mp4 we can use a codec rather than proper conversion.  Both are wrappers around other formats, so this conversion loses less quality than other conversion types.

-> ffmpeg -i LostInTranslation.mkv -codec copy LostInTranslation.mp4
+```bash
+ffmpeg -i LostInTranslation.mkv -codec copy LostInTranslation.mp4
+```

 Opus to mp3

-> ffmpeg -i song.opus song.mp3
+```bash
+ffmpeg -i song.opus song.mp3
+```

-> ffmpeg -i video.flv video.mpeg
+```bash
+ffmpeg -i video.flv video.mpeg
+```

-> ffmpeg -i input.webm -qscale 0 output.mp4
+```bash
+ffmpeg -i input.webm -qscale 0 output.mp4
+```

 # Video to Audio

-> ffmpeg -i input.mp4 -vn output.mp3
+```bash
+ffmpeg -i input.mp4 -vn output.mp3
+```


 # Convert all mkv files to mp4

-> for i in *.mkv; do
+```bash
+for i in *.mkv; do
+```

    > ffmpeg -i "$i" -codec copy "${i%.*}.mp4"

-> done
+```bash
+done
+```


 # Change resolution

-> ffmpeg -i input.mp4 -filter:v scale=1280:720 -c:a copy output.mp4
+```bash
+ffmpeg -i input.mp4 -filter:v scale=1280:720 -c:a copy output.mp4
+```

 Or just crop:

-> ffmpeg -i input.mp4 -filter:v "crop=w:h:x:y" output.mp4
+```bash
+ffmpeg -i input.mp4 -filter:v "crop=w:h:x:y" output.mp4
+```

 Or aspect ratio:

-> ffmpeg -i input.mp4 -aspect 16:9 output.mp4
+```bash
+ffmpeg -i input.mp4 -aspect 16:9 output.mp4
+```

 Or trim to start and stop times:

-> ffmpeg -i input.mp4 -ss 00:00:50 -codec copy -t 50 output.mp4
+```bash
+ffmpeg -i input.mp4 -ss 00:00:50 -codec copy -t 50 output.mp4
+```

 Indicate start times with -ss and time with -t in seconds.

 Or split a video into parts:

-> ffmpeg -i input.mp4 -t 00:00:30 -c copy part1.mp4 -ss 00:00:30 -codec copy part2.mp4
+```bash
+ffmpeg -i input.mp4 -t 00:00:30 -c copy part1.mp4 -ss 00:00:30 -codec copy part2.mp4
+```


 # Compress Video

-> ffmpeg -i input.mp4 -vf scale=1280:-1 -c:v libx264 -preset veryslow -crf 24 output.mp4
+```bash
+ffmpeg -i input.mp4 -vf scale=1280:-1 -c:v libx264 -preset veryslow -crf 24 output.mp4
+```

 # Extract Images from Video

 -r sets the frame rate, and -f selects the format.

-> ffmpeg -i input.mp4 -r 1 -f image2 image-%2d.png
+```bash
+ffmpeg -i input.mp4 -r 1 -f image2 image-%2d.png
+```

 # Add Images to Audio

-> $ ffmpeg -loop 1 -i inputimage.jpg -i inputaudio.mp3 -c:v libx264 -c:a aac -strict experimental -b:a 192k -shortest output.mp4
-
-# Create a Video from Multiple Parts
-
-First make a text file indicating all the parts, e.g.
-
+```bash
+$ ffmpeg -loop 1 -i inputimage.jpg -i inputaudio.mp3 -c:v libx264 -c:a aac -strict experimental -b:a 192k -shortest output.mp4
 ```

-file /home/sk/myvideos/part1.mp4
-file /home/sk/myvideos/part2.mp4
-file /home/sk/myvideos/part3.mp4
-file /home/sk/myvideos/part4.mp4
-
-```
-
-Then join with:
-
-> ffmpeg -f concat -i join.txt -c copy output.mp4
-
 # Add Subtitles

-> fmpeg -i input.mp4 -i subtitle.srt -map 0 -map 1 -c copy -c:v libx264 -crf 23 -preset veryfast output.mp4
+```bash
+fmpeg -i input.mp4 -i subtitle.srt -map 0 -map 1 -c copy -c:v libx264 -crf 23 -preset veryfast output.mp4
+```

--- a/vision/imagemagick.md
+++ b/vision/imagemagick.md
@@ -6,48 +6,68 @@ tags: [ "Documentation", "Vision" ]

 Convert jpg to png.

-> convert image.jpg image.png
+```bash
+convert image.jpg image.png
+```

-> convert image.jpg -quality 50 image.jpg
+```bash
+convert image.jpg -quality 50 image.jpg
+```

 'Quality' must be from 1 to 100.

-> convert -resize 50% image.jpg image2.jpg
+```bash
+convert -resize 50% image.jpg image2.jpg
+```

 Resizing only changes jpegs.  Change a png with:

-> convert input.png png8:out.png
+```bash
+convert input.png png8:out.png
+```

 # Invert Colours

-> convert input.jpg output.jpg -negate
+```bash
+convert input.jpg output.jpg -negate
+```

 # Make Images Smaller

-> convert image.jpg -resize 25% output.jpg
+```bash
+convert image.jpg -resize 25% output.jpg
+```


 # Trim images to border

 This is generally used for transparrent images.

-> convert -trim image.png output.png
+```bash
+convert -trim image.png output.png
+```

 Make the white of an image transparrent.

-> convert -transparent white -fuzz 10% input.png output.png
+```bash
+convert -transparent white -fuzz 10% input.png output.png
+```

 The 'fuzz' option tells the computer that 'close to white' is fine.  You might want to use 20% or higher fuzz.


 ## Dropshadow

-> `convert <input file> \( +clone -background black -shadow 50x8+0+5 \) +swap -background none -layers merge +repage <output file>`
+```bash
+`convert <input file> \( +clone -background black -shadow 50x8+0+5 \) +swap -background none -layers merge +repage <output file>`
+```


 # Convert every jpg in directory to png

-> mogrify -format png *.jpg
+```bash
+mogrify -format png *.jpg
+```

 # Printing Words

@@ -77,14 +97,20 @@ $potrace -s output.ppm -o svgout.svg

 See your installed fonts:

-> convert -list font
+```bash
+convert -list font
+```

 Make na image showing day of the week:

-> convert -fill blue -font Sauce-Code-Pro-Semibold-Nerd-Font-Complete-Mono -gravity center -pointsize 79 label:$(date +%A) day.png
+```bash
+convert -fill blue -font Sauce-Code-Pro-Semibold-Nerd-Font-Complete-Mono -gravity center -pointsize 79 label:$(date +%A) day.png
+```


 Make a meme:

-> convert inputmemeimage.png -font impact -fill white -pointsize 84 -stroke black -strokewidth 3 -gravity north -annotate +0+20 'TOP MEME TEXT' -gravity south -annotate +0+20 'BOTTOM MEME TEXT' outputmemeimage.png
+```bash
+convert inputmemeimage.png -font impact -fill white -pointsize 84 -stroke black -strokewidth 3 -gravity north -annotate +0+20 'TOP MEME TEXT' -gravity south -annotate +0+20 'BOTTOM MEME TEXT' outputmemeimage.png
+```

--- a/vision/qrencode.md
+++ b/vision/qrencode.md
@@ -5,9 +5,13 @@ tags: [ "Documentation", "vision" ]

 Make a QR Code image:

-> qrencode 'https://play.google.com/store/apps/details?id=org.briarproject.briar.android' -o qr_briar.png
+```bash
+qrencode 'https://play.google.com/store/apps/details?id=org.briarproject.briar.android' -o qr_briar.png
+```

 Make a QR Coded message in the terminal:

-> qrencode -t ansi "Hello World"
+```bash
+qrencode -t ansi "Hello World"
+```