Added video to epub converter

This script is somewhat ridiculous. It takes a video and .vtt
subtitles file and converts it to an .epub file with images for each
subtitle. This makes it possible to "read" a TV episode on an E-Ink
tablet, for example.

I made this because I'm not good enough at listening to Japanese at
full speed. Now, I can "read the episode" first, then watch it later.

ReadMe.org

@@ -68,6 +68,28 @@ This script automatically detects Japanese articles based on whether there are a
 - Paste the token string into ~src/Calibre_Wallabag_To_EPUB.recipe~ at the URL line, along with your username
 - Run the corresponding ~DownloadCalibreArticles*.sh~ script to create a .epub in the same directory with your articles
 - Read that with an EPUB reader, e.g. [[https://github.com/makuto/typhon][Typhon]], with good Japanese dictionary support
+** Using the Video to EPUB script
+This script is somewhat ridiculous. It takes a video and .vtt subtitles file and converts it to an .epub file with images for each subtitle. This makes it possible to "read" a TV episode on an E-Ink tablet, for example.
+
+I made this because I'm not good enough at listening to Japanese at full speed. Now, I can "read the episode" first, then watch it later.
+
+The full pipeline requires both ~ffmpeg~ and ~pandoc~:
+
+#+BEGIN_SRC sh
+sudo apt install ffmpeg pandoc
+#+END_SRC
+
+And here's how to run it:
+
+#+BEGIN_SRC sh
+# Run the script
+python3 VideoToEPUB.py MyVideo.mp4 MyVideo.ja.vtt output/
+# Convert to EPUB
+pandoc -f org -t epub output/MyVid.org -o ~/Documents/MyVid.epub
+#+END_SRC
+
+Note that this should work for any language, so long as the subtitles file is ~.vtt~ format. Any video format supported by ffmpeg should work.
+
 * License
 The repository itself is under the MIT license.
 

src/VideoToEPUB.py

@@ -0,0 +1,68 @@
+import sys
+import subprocess
+import os
+import pathlib
+
+def makeDirIfNonexistant(directory):
+    if not os.path.exists(directory):
+        os.makedirs(directory)
+
+def main(videoToConvertName, subtitleFilename, outputDir):
+    subtitleFile = open(subtitleFilename, 'r')
+
+    subtitleLines = subtitleFile.readlines()
+    subtitleFile.close()
+
+    makeDirIfNonexistant(outputDir)
+    videoPath = pathlib.Path(videoToConvertName)
+    outputPath = pathlib.Path(outputDir)
+    videoName = videoPath.stem
+    outputFilename = outputPath / (videoName + '.org')
+
+    outputLines = []
+
+    outputLines.append("#+TITLE:{}\n\n".format(videoName))
+
+    accumulatedText = []
+    previousLine = None
+    # Skip first line (it's the format specifier)
+    for subtitleLine in subtitleLines[1:]:
+        # Detected subtitle timestamp
+        if '-->' in subtitleLine:
+            # Finish writing the last subtitle
+            # Lop off the previousLine number
+            if accumulatedText:
+                accumulatedText = accumulatedText[:-1]
+            outputLines.extend(accumulatedText)
+
+            # Make subtitle number the chapter title
+            outputLines.append('* ' + previousLine)
+            subtitleNumber = int(previousLine.strip())
+            outputImageFilename = outputPath / "{}.{}".format(subtitleNumber, 'jpg')
+            # TODO: Use the middle of the range instead?
+            screenshotTimestamp = subtitleLine[:12]
+            print(['ffmpeg', '-ss', screenshotTimestamp, '-i', videoToConvertName,
+                   '-vframes', '1', '-q:v', '2', outputImageFilename])
+            # Note that this will do any space escaping necessary for us
+            # Never overwrite output files
+            subprocess.call(['ffmpeg', '-ss', screenshotTimestamp, '-n', '-i', videoToConvertName,
+                             '-vframes', '1', '-q:v', '2', outputImageFilename])
+            outputLines.append('\n[[file:{}]]\n\n'.format(outputImageFilename.name))
+            accumulatedText = []
+        # Get the actual subtitle text
+        # Ignore newlines
+        elif subtitleLine.strip():
+            accumulatedText.append(subtitleLine)
+
+        previousLine = subtitleLine
+
+    outputFile = open(outputFilename, 'w')
+    outputFile.writelines(outputLines)
+    outputFile.close()
+
+if __name__ == "__main__":
+    if len(sys.argv) != 4:
+        print("Usage:\npython3 VideoToEPUB.py [Video file] [VTT subtitle file] [output directory]")
+        print("\nNote that this script runs ffmpeg from the command line. Ensure it is in your PATH")
+    else:
+        main(sys.argv[1], sys.argv[2], sys.argv[3])