add multiprocessing

README.md

@@ -90,6 +90,7 @@ usage: main.py [-h] [--tts {azure,openai,edge,piper}]
                [--chapter_start CHAPTER_START] [--chapter_end CHAPTER_END]
                [--output_text] [--remove_endnotes]
                [--search_and_replace_file SEARCH_AND_REPLACE_FILE]
+               [--worker_count WORKER_COUNT]
                [--voice_name VOICE_NAME] [--output_format OUTPUT_FORMAT]
                [--model_name MODEL_NAME] [--voice_rate VOICE_RATE]
                [--voice_volume VOICE_VOLUME] [--voice_pitch VOICE_PITCH]
@@ -164,6 +165,14 @@ options:
                         is: <search>==<replace> Note that you may have to
                         specify word boundaries, to avoid replacing parts of
                         words.
+  --worker_count WORKER_COUNT
+                        Specifies the number of parallel workers to use for 
+                        audiobook generation. Increasing this value can 
+                        significantly speed up the process by processing 
+                        multiple chapters simultaneously. Note: Chapters may 
+                        not be processed in sequential order, but this will 
+                        not affect the final audiobook.
+
   --voice_name VOICE_NAME
                         Various TTS providers has different voice names, look
                         up for your provider settings.

audiobook_generator/config/general_config.py

@@ -8,6 +8,7 @@ def __init__(self, args):
         self.log = args.log
         self.no_prompt = args.no_prompt
         self.title_mode = args.title_mode
+        self.worker_count = args.worker_count
 
         # Book parser specific arguments
         self.newline_mode = args.newline_mode
@@ -39,4 +40,4 @@ def __init__(self, args):
         self.piper_length_scale = args.piper_length_scale
 
     def __str__(self):
-        return ', '.join(f"{key}={value}" for key, value in self.__dict__.items())
+        return ", ".join(f"{key}={value}" for key, value in self.__dict__.items())

audiobook_generator/core/audiobook_generator.py

@@ -1,4 +1,5 @@
 import logging
+import multiprocessing
 import os
 
 from audiobook_generator.book_parsers.base_book_parser import get_book_parser
@@ -31,6 +32,36 @@ def __init__(self, config: GeneralConfig):
     def __str__(self) -> str:
         return f"{self.config}"
 
+    def process_chapter(self, idx, title, text, book_parser, tts_provider):
+        """Process a single chapter: write text (if needed) and convert to audio."""
+        try:
+            logger.info(f"Processing chapter {idx}: {title}")
+
+            # Save chapter text if required
+            if self.config.output_text:
+                text_file = os.path.join(self.config.output_folder, f"{idx:04d}_{title}.txt")
+                with open(text_file, "w", encoding="utf-8") as f:
+                    f.write(text)
+
+            # Skip audio generation in preview mode
+            if self.config.preview:
+                return
+
+            # Generate audio file
+            output_file = os.path.join(
+                self.config.output_folder,
+                f"{idx:04d}_{title}.{tts_provider.get_output_file_extension()}",
+            )
+            audio_tags = AudioTags(
+                title, book_parser.get_book_author(), book_parser.get_book_title(), idx
+            )
+            tts_provider.text_to_speech(text, output_file, audio_tags)
+
+            logger.info(f"✅ Converted chapter {idx}: {title}")
+        except Exception:
+            logger.exception(f"Error processing chapter {idx}")
+            raise
+
     def run(self):
         try:
             book_parser = get_book_parser(self.config)
@@ -59,10 +90,14 @@ def run(self):
                     f"Chapter start index {self.config.chapter_start} is larger than chapter end index {self.config.chapter_end}. Check your input."
                 )
 
-            logger.info(f"Converting chapters from {self.config.chapter_start} to {self.config.chapter_end}.")
+            logger.info(
+                f"Converting chapters from {self.config.chapter_start} to {self.config.chapter_end}."
+            )
 
             # Initialize total_characters to 0
-            total_characters = get_total_chars(chapters[self.config.chapter_start - 1:self.config.chapter_end])
+            total_characters = get_total_chars(
+                chapters[self.config.chapter_start - 1 : self.config.chapter_end]
+            )
             logger.info(f"✨ Total characters in selected book chapters: {total_characters} ✨")
             rough_price = tts_provider.estimate_cost(total_characters)
             print(f"Estimate book voiceover would cost you roughly: ${rough_price:.2f}\n")
@@ -75,36 +110,19 @@ def run(self):
             else:
                 confirm_conversion()
 
-            # Loop through each chapter and convert it to speech using the provided TTS provider
-            for idx, (title, text) in enumerate(chapters, start=1):
-                if idx < self.config.chapter_start:
-                    continue
-                if idx > self.config.chapter_end:
-                    break
-                logger.info(
-                    f"Converting chapter {idx}/{len(chapters)}: {title}, characters: {len(text)}"
+            # Prepare chapters for processing
+            chapters_to_process = chapters[self.config.chapter_start - 1 : self.config.chapter_end]
+            tasks = (
+                (idx, title, text, book_parser, tts_provider)
+                for idx, (title, text) in enumerate(
+                    chapters_to_process, start=self.config.chapter_start
                 )
+            )
 
-                if self.config.output_text:
-                    text_file = os.path.join(self.config.output_folder, f"{idx:04d}_{title}.txt")
-                    with open(text_file, "w", encoding='utf-8') as file:
-                        file.write(text)
-
-                if self.config.preview:
-                    continue
+            # Use multiprocessing to process chapters in parallel
+            with multiprocessing.Pool(processes=self.config.worker_count) as pool:
+                pool.starmap(self.process_chapter, tasks)
 
-                output_file = os.path.join(self.config.output_folder,
-                                           f"{idx:04d}_{title}.{tts_provider.get_output_file_extension()}")
-
-                audio_tags = AudioTags(title, book_parser.get_book_author(), book_parser.get_book_title(), idx)
-                tts_provider.text_to_speech(
-                    text,
-                    output_file,
-                    audio_tags,
-                )
-                logger.info(
-                    f"✅ Converted chapter {idx}/{len(chapters)}: {title}"
-                )
             logger.info(f"All chapters converted. 🎉🎉🎉")
 
         except KeyboardInterrupt:

main.py

@@ -83,6 +83,15 @@ def handle_args():
         """,
     )
 
+    parser.add_argument(
+        "--worker_count",
+        type=int,
+        default=1,
+        help="Specifies the number of parallel workers to use for audiobook generation. "
+        "Increasing this value can significantly speed up the process by processing multiple chapters simultaneously. "
+        "Note: Chapters may not be processed in sequential order, but this will not affect the final audiobook.",
+    )
+
     parser.add_argument(
         "--voice_name",
         help="Various TTS providers has different voice names, look up for your provider settings.",