You need to have installed "ImageMagick" or "GraphicsMagick"
In Ubuntu or Debian you can install it with the command:
sudo apt install imagemagick
or
sudo apt install graphicsmagick
Then you go to your work directory.
cd my/work/directory/path
And write the command
convert myfile.jpg myfile.pdf
Or with GraphicsMagick
gm convert file.jpg file.pdf
To convert multiple images:
gm convert file1.png file2.png file3.jpg file.pdf
For more, just run:
man gm
With ImageMagick you can also convert multiple JPG files into one multi-image PDF
convert *.jpg -adjoin myfiles.pdf
To merge multiple PDFs into one file:
$ pdftk file1.pdf file2.pdf file3.pdf cat output file123.pdf
CONVERTING WITH IMG2PDF
In Ubuntu or Debian you can install it with the command:
sudo apt install imagemagick
or
sudo apt install graphicsmagick
Then you go to your work directory.
cd my/work/directory/path
And write the command
convert myfile.jpg myfile.pdf
Or with GraphicsMagick
gm convert file.jpg file.pdf
To convert multiple images:
gm convert file1.png file2.png file3.jpg file.pdf
For more, just run:
man gm
With ImageMagick you can also convert multiple JPG files into one multi-image PDF
convert *.jpg -adjoin myfiles.pdf
To merge multiple PDFs into one file:
$ pdftk file1.pdf file2.pdf file3.pdf cat output file123.pdf
CONVERTING WITH IMG2PDF
sudo apt install img2pdf
img2pdf --pagesize Letter input.jpg -o output.pdf
man img2pdf
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