Adding annotations/subtitles to Kivy Videoplayer in Python

Question

I'm trying to add Subtitles to my videoplayer in Kivy from a URL. This is what I have done so far. First I just added the subtitle link to the property, just like I would add the source link for the video

VideoPlayer:
    source: root.vid_source
    options: {'allow_stretch': True, 'eos': 'loop'}
    annotations: root.subs_source  ## This doesnt work

According to the Kivy documentation I require a 'jsa' file with list like this I suppose

[
    {"start": 0, "duration": 2,
    "text": "This is an example of annotation"},
    {"start": 2, "duration": 2,
    "bgcolor": [0.5, 0.2, 0.4, 0.5],
    "text": "You can change the background color"}
]

but the source link contains text of this format (a dictionary with 'captions' key is what I need)

{"captions":[{"duration":1961,"content":"When you have 21 minutes to speak,","startOfParagraph":true,"startTime":1610},{"duration":2976,"content":"two million years seems\nlike a really long time.","startOfParagraph":false,"startTime":3595}

So I created a new Class to parse the subtitles in the given format

class Subtitles:

    def __init__(self, url):
        self.parsed_subs = []
        req = UrlRequest(url, self.got_subtitles)

    def got_subtitles(self, req, results):
        self.parsed_subs = [{"start":sub["startTime"],"duration":sub["duration"], "text": sub["content"]} for sub in results['captions']]

    def get_subtitles(self):
        return self.parsed_subs

with following changes to my Kv file

#:import playerapp playerapp

VideoPlayer:
  .......
  #### str conversion since it says it accepts only string####
  annotations: str(playerapp.Subtitles(root.subs_source).get_subtitles())

But it didnt work.

After taking at a look at the source code for VideoPlayer I see that while initializing the VideoPlayer it creates self._annotations_labels which it populates with what's returned by VideoAnnotation class, so maybe somehow I need to put the above parsed_subs inside the self._annotations_labels but I'm getting confused here.

Answer 1

I have managed a workaround to the problem. Firstly, the UrlRequest wasn't working because I was using this outside the Kivy App and turns out it doesn't work like that. So I used urllib library or maybe you could use requests library and that was pretty much it, the mistake I was making. Also after parsing I saved the file in a subtitles.jsa file , which is what 'annotations' property requires and it works now.