add srt subtitle export utility (openai#102)

* add srt subtitle export utility * simplifying Co-authored-by: Jong Wook Kim <[email protected]>
MiscellaneousStuff · Sep 26, 2022 · ead77fa · ead77fa
1 parent 5485428
commit ead77fa
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Showing 2 changed files with 35 additions and 3 deletions.
diff --git a/whisper/transcribe.py b/whisper/transcribe.py
@@ -10,7 +10,7 @@
 from .audio import SAMPLE_RATE, N_FRAMES, HOP_LENGTH, pad_or_trim, log_mel_spectrogram
 from .decoding import DecodingOptions, DecodingResult
 from .tokenizer import LANGUAGES, TO_LANGUAGE_CODE, get_tokenizer
-from .utils import exact_div, format_timestamp, optional_int, optional_float, str2bool, write_vtt
+from .utils import exact_div, format_timestamp, optional_int, optional_float, str2bool, write_vtt, write_srt
 
 if TYPE_CHECKING:
  from .model import Whisper
@@ -301,6 +301,10 @@ def cli():
  with open(os.path.join(output_dir, audio_basename + ".vtt"), "w", encoding="utf-8") as vtt:
  write_vtt(result["segments"], file=vtt)
 
+ # save SRT
+ with open(os.path.join(output_dir, audio_basename + ".srt"), "w", encoding="utf-8") as srt:
+ write_srt(result["segments"], file=srt)
+
 
 if __name__ == '__main__':
  cli()
diff --git a/whisper/utils.py b/whisper/utils.py
@@ -27,7 +27,7 @@ def compression_ratio(text) -> float:
  return len(text) / len(zlib.compress(text.encode("utf-8")))
 
 
-def format_timestamp(seconds: float):
+def format_timestamp(seconds: float, always_include_hours: bool = False):
  assert seconds >= 0, "non-negative timestamp expected"
  milliseconds = round(seconds * 1000.0)
 
@@ -40,7 +40,8 @@ def format_timestamp(seconds: float):
  seconds = milliseconds // 1_000
  milliseconds -= seconds * 1_000
 
- return (f"{hours}:" if hours > 0 else "") + f"{minutes:02d}:{seconds:02d}.{milliseconds:03d}"
+ hours_marker = f"{hours}:" if always_include_hours or hours > 0 else ""
+ return f"{hours_marker}{minutes:02d}:{seconds:02d}.{milliseconds:03d}"
 
 
 def write_vtt(transcript: Iterator[dict], file: TextIO):
@@ -52,3 +53,30 @@ def write_vtt(transcript: Iterator[dict], file: TextIO):
  file=file,
  flush=True,
  )
+
+
+def write_srt(transcript: Iterator[dict], file: TextIO):
+ """
+ Write a transcript to a file in SRT format.
+
+ Example usage:
+ from pathlib import Path
+ from whisper.utils import write_srt
+
+ result = transcribe(model, audio_path, temperature=temperature, **args)
+
+ # save SRT
+ audio_basename = Path(audio_path).stem
+ with open(Path(output_dir) / (audio_basename + ".srt"), "w", encoding="utf-8") as srt:
+ write_srt(result["segments"], file=srt)
+ """
+ for i, segment in enumerate(transcript, start=1):
+ # write srt lines
+ print(
+ f"{i}\n"
+ f"{format_timestamp(segment['start'], always_include_hours=True)} --> "
+ f"{format_timestamp(segment['end'], always_include_hours=True)}\n"
+ f"{segment['text'].strip().replace('-->', '->')}\n",
+ file=file,
+ flush=True,
+ )