def develop_drawn_clip(org_clip: VideoFileClip, sq_frames: List[float], all_frames: List[np.ndarray],
buffer_s: float = 1) -> VideoClip:
"""Calculates subclip start and end time, creates a subclip to reference.
Combines the drawn frames (with buffer) before transforming into a video clip
Adds original clip's audio to the video containing drawn frames.
Args:
org_clip: the original clip to leverage audio, duration data from
sq_frames: the sequence of frames that have motion annotations draw in them
all_frames: the full list of frames that we'll be slicing
buffer_s: the seconds of buffer to add before and after the motion area
"""
duration = org_clip.duration
tot_frames = len(all_frames)
# Calculate number of frames to buffer before and after motion areas
buffer_fr = int(org_clip.fps * buffer_s)
# Calculate the start and end frames with the buffers
st_with_buffer = sq_frames[0]
end_with_buffer = sq_frames[-1] + buffer_fr
start_frame_pos = st_with_buffer if st_with_buffer > 0 else 0
end_frame_pos = end_with_buffer if end_with_buffer < tot_frames else tot_frames - 1
# Calculate the start and end times for the start and end frames
start_t = ((start_frame_pos / tot_frames) * duration)
end_t = ((end_frame_pos / tot_frames) * duration)
# Cut the original clip to fit the buffer
cut_clip = org_clip.subclip(start_t, end_t)
# Generate the sequence of drawn clips
drawn_clip = ImageSequenceClip(all_frames[start_frame_pos:end_frame_pos], fps=org_clip.fps)
if drawn_clip.duration != cut_clip.duration:
# Cut the tail off the drawn clip to match the cut_clip.
drawn_clip = drawn_clip.subclip(0, end_t - start_t)
# Make the drawn clip a VideoClip by concatenating it with only itself. Add original clip's audio
drawn_clip = concatenate_videoclips([drawn_clip])
drawn_clip.audio = cut_clip.audio
return drawn_clip
