Source code for lecture2notes.end_to_end.frames_extractor

import logging
import os

from .helpers import make_dir_if_not_exist

logger = logging.getLogger(__name__)


def extract_frames(input_video_path, quality, output_path, extract_every_x_seconds):
    """Extracts frames from `input_video_path` at quality level `quality` (best quality is 2) every `extract_every_x_seconds seconds` and saves them to `output_path`"""
    quality = str(quality)
    output_path = str(output_path)
    extract_every_x_seconds = str(extract_every_x_seconds)
    logger.debug(
        "Received inputs\ninput_video_path="
        + str(input_video_path)
        + "\nquality="
        + str(quality)
        + "\noutput_path="
        + str(output_path)
    )
    make_dir_if_not_exist(output_path)
    command = (
        "ffmpeg -i "
        + str(input_video_path)
        + ' -vf "fps=1/'
        + str(extract_every_x_seconds)
        + '" -q:v '
        + str(quality)
        + " "
        + str(output_path)
        + "/img_%05d.jpg"
    )

    logger.debug("Running command: " + command)
    os.system(command)

    for filename in os.listdir(output_path):
        if filename.endswith(".jpg"):
            new_number = int(filename.split("_")[1].split(".")[0]) * int(
                extract_every_x_seconds
            )
            new_filename = "img_" + str(new_number).zfill(5) + ".jpg"
            os.rename(
                os.path.join(output_path, filename),
                os.path.join(output_path, new_filename),
            )

    logger.info(
        "Frame extraction successful. Returning output_path=" + str(output_path)
    )
    return output_path