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Subtitles Class

Subtitles

From a raw FFmpeg extraction, process the text and translate it using a given Translator object.

Parameters:

Name Type Description Default
raw_subtitles list[str]

Subtitles line by line

 required
sub_format str

sub_format of the extracted subtitles. Defaults to "srt".

 'srt'
Source code in subtitles_translator/subtitles.py 
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class Subtitles:
    """From a raw FFmpeg extraction, process the text and translate it using a given
    Translator object.

    Args:
        raw_subtitles (list[str]): Subtitles line by line
        sub_format (str, optional): sub_format of the extracted subtitles. Defaults to "srt".

    """

    def __init__(self, raw_subtitles: list[str], sub_format: str = "srt") -> None:
        self.raw_subtitles = raw_subtitles
        self.sub_format = sub_format

        self.full_text_lines: list[str] = []

        self.aggregated_text_lines: list[str] = []
        self.aggregated_dico_lines: dict[str, list[list]] = {}

        self.build_aggregated_dico()

    def build_aggregated_dico(self) -> None:
        """After converting raw extraction to list of lines, aggregates and clean lines
        in order to be able to translate them. When two lines are combined, both indexes
        are saved in order to replace each line at the end.

        """
        seen_i = set()
        n = len(self.raw_subtitles)

        for i, line in enumerate(self.raw_subtitles):
            self.full_text_lines.append(line)
            if i in seen_i or "-->" in line:
                continue
            agg_line = ""
            if i < n - 1 and self.raw_subtitles[i + 1] == "":
                agg_line += line
                seen_i.add(i)
                self.aggregated_text_lines.append(agg_line)
                if agg_line in self.aggregated_dico_lines:
                    self.aggregated_dico_lines[agg_line].append([i])
                else:
                    self.aggregated_dico_lines[agg_line] = [[i]]
            # the following condition means that we are on the second part of a two lines subtitle text
            if i > 0 and i < n - 2 and self.raw_subtitles[i + 2] == "" and self.raw_subtitles[i - 1] != "":
                seen_i.add(i)
                seen_i.add(i + 1)
                agg_line += line + " " + self.raw_subtitles[i + 1]
                self.aggregated_text_lines.append(self.raw_subtitles[i + 1])
                if agg_line in self.aggregated_dico_lines:
                    self.aggregated_dico_lines[agg_line].append([i, i + 1])
                else:
                    self.aggregated_dico_lines[agg_line] = [[i, i + 1]]

    def save_srt(self, path: str | os.PathLike = "translated.srt") -> None:
        """Save current subtitles into an srt files.
        If translate_subtitles was called before, this results in a translated srt file.

        Args:
            path (str | os.PathLike, optional): Path to the target SRT file. Defaults to "translated.srt". It is always saved, it is used to put back subtitles with FFmpeg.

        """
        with open(path, "w", encoding="utf-8") as file:
            for line in self.full_text_lines:
                # in Python we need to write blank lines manually (those in full_text_lines are skipped by default)
                if line == "":
                    file.write("\n")
                else:
                    file.write(line)
                    file.write("\n")

build_aggregated_dico()

After converting raw extraction to list of lines, aggregates and clean lines in order to be able to translate them. When two lines are combined, both indexes are saved in order to replace each line at the end.

Source code in subtitles_translator/subtitles.py 
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def build_aggregated_dico(self) -> None:
    """After converting raw extraction to list of lines, aggregates and clean lines
    in order to be able to translate them. When two lines are combined, both indexes
    are saved in order to replace each line at the end.

    """
    seen_i = set()
    n = len(self.raw_subtitles)

    for i, line in enumerate(self.raw_subtitles):
        self.full_text_lines.append(line)
        if i in seen_i or "-->" in line:
            continue
        agg_line = ""
        if i < n - 1 and self.raw_subtitles[i + 1] == "":
            agg_line += line
            seen_i.add(i)
            self.aggregated_text_lines.append(agg_line)
            if agg_line in self.aggregated_dico_lines:
                self.aggregated_dico_lines[agg_line].append([i])
            else:
                self.aggregated_dico_lines[agg_line] = [[i]]
        # the following condition means that we are on the second part of a two lines subtitle text
        if i > 0 and i < n - 2 and self.raw_subtitles[i + 2] == "" and self.raw_subtitles[i - 1] != "":
            seen_i.add(i)
            seen_i.add(i + 1)
            agg_line += line + " " + self.raw_subtitles[i + 1]
            self.aggregated_text_lines.append(self.raw_subtitles[i + 1])
            if agg_line in self.aggregated_dico_lines:
                self.aggregated_dico_lines[agg_line].append([i, i + 1])
            else:
                self.aggregated_dico_lines[agg_line] = [[i, i + 1]]

save_srt(path='translated.srt')

Save current subtitles into an srt files. If translate_subtitles was called before, this results in a translated srt file.

Parameters:

Name Type Description Default
path str | os.PathLike

Path to the target SRT file. Defaults to "translated.srt". It is always saved, it is used to put back subtitles with FFmpeg.

 'translated.srt'
Source code in subtitles_translator/subtitles.py 
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def save_srt(self, path: str | os.PathLike = "translated.srt") -> None:
    """Save current subtitles into an srt files.
    If translate_subtitles was called before, this results in a translated srt file.

    Args:
        path (str | os.PathLike, optional): Path to the target SRT file. Defaults to "translated.srt". It is always saved, it is used to put back subtitles with FFmpeg.

    """
    with open(path, "w", encoding="utf-8") as file:
        for line in self.full_text_lines:
            # in Python we need to write blank lines manually (those in full_text_lines are skipped by default)
            if line == "":
                file.write("\n")
            else:
                file.write(line)
                file.write("\n")