YoloCR

I cleaned the vpy so they use a config file and are somewhat pep8 compliant and as such more readable. This is a fork, for the original see the link in the title. There's also a PKGBUILD, don't try to use it, it doesn't work

For noobs

Install the requirements with the Ubuntu 20.04 (Focal Fossa) installation script. You can install Ubuntu 20.04 inside a virtual machine like Virtualbox.

Requirements

Global Requirements for all the OS.

Global Requirements

• ffmpeg

• Vapoursynth R36+

  • plugins for Vapoursynth:

    • FFMS2
    • HAvsFunc, requires mvsfunc and adjust
    • fmtconv
    • optional: edi_rpow2, requires znedi3
    • very optional: Waifu2x-w2xc

  • note:

    • Vapoursynth plugins (.so on Unix, .dll on Windows) should be placed inside one of theses directories: http://www.vapoursynth.com/doc/autoloading.html
    • Vapoursynth scripts (.py) should be placed inside the "site-packages" directory of your Python3 installation.

  • Vapoursynth Editor

Unix/Linux Requirements

• Tesseract-OCR (>=4)

  • and install the data corresponding to the languages you want to OCR

• Imagemagick

Note: most of these package, with the exception of all the plugins for vapoursynth, are available as official package for your distro. For Ubuntu 20.04, all the requirements can be installed with the YoloBuntuInstallation script : sh YoloBuntuInstallation.sh eng-only For Ubuntu, vapoursynth, vapoursynth-editor and vapoursynth-extra-plugins (to install all the mandatory plugins above) are available through this ppa: ppa:djcj/vapoursynth

Windows Requirements

• Cygwin. During the install, activate:
  • bc
  • gnupg
  • make
  • perl
  • wget
  • tesseract-ocr
  • tesseract-ocr-eng

Note: Cygwin terminal usage here → https://help.ubuntu.com/community/UsingTheTerminal C drive path is "/cygdrive/c". Scripts have to be used within Cygwin terminal. If you use Windows 10, you can install BashOnWindows instead of Cygwin.

How to use

Help for determining the parameters for the config file

Determine the Resize parameters

Resize is very helpful to locate the subtitles.

1. open the config file in a text editor

2. open YoloResize.py in Vapoursynth Editor.

3. Change these values in the config:

   • source_file is the path of the video to OCR.
   • crop_box_dimension allows you to limit the OCR zone.
   • crop_box_height allows you to define the height of the Cropbox's bottom border.

Note that theses two parameters have to be adjusted before upscale.

You can then change supersampling_factor parameter to -1 and verify that your subtitles aren't eated by the white borderline by using F5.

Determine the threshold of the subtitles

This part is made to improve the OCR process and the subtitles detection.

1. Open YoloSeuil.py in Vapoursynth editor.
2. Choose the fitting threshold_mode. 'L' if you want to define a white or black threshold, succesively 'R', 'G' and 'B' otherwise.
3. Adjust the Threshold with the help of the "Color Panel" found in the F5 window.

You must to do this two times if you are using threshold_mode="L":

• in the first case, the Inline threshold will be the minimum.
• in the second case, the Outline threshold will be the maximum.

You can then change threshold paremeter to the values previously found.

• in the first case, the subtitles must remain completely visible. The highest the value, the better.
• in the second case, the Outline must remain completely black. The lowest the value, the better.

Filter the video + OCR

1. Edit inline_threshold and outline_threshold thanks to the two previous steps

   • inline_threshold = the inline threshold value (decrease it if it improves the clarity of the letters)
   • outline_threshold = the outline threshold value (increase it if some letters got erased)

2. Then filter it: vspipe -y yolocr/YoloCR.py . -p

You can use yolocr/yolocr-cli.py to set the values while also executing the script You can use YoloTime.sh instead of yolocr.py if you only want the Timing of the subtitles. NOT SUPPORTED ANYMORE

Now it's Checking time :D

Serial use of YoloCR

1. Make sure that the directory you're in includes the video files you want to OCR and only theses.

2. Move to the YoloCR directory and use this bash command:

   • for file in *.mp4; do ./yolocr/yolocr-cli.py -f "$file" -l eng; done

"*.mp4" means that all files having the mp4 extension will be processed. You can change eng for the language you want. Read about bash regex if you want more flexibility.