描述 #

音频格式转换处理器

核心功能 #

• 支持音频格式转换（WAV、MP3、FLAC）
• 自动选择合适的编码器
• 通过extra_params支持自定义ffmpeg参数
• 支持本地文件、HTTP/HTTPS URL和TOS/S3存储

格式支持 #

• 输入：WAV、FLAC、MP3、AAC、M4A、OGG、WMA、APE等主流音频格式
• 输出：WAV (pcm_s16le)、MP3 (libmp3lame)、FLAC (flac)

算子参数 #

输入 #

输出 #

包含转换结果路径的数组，成功返回输出路径，失败返回None

参数 #

如参数没有默认值，则为必填参数

调用示例 #

下面的代码展示了如何使用 Daft（适用于分布式）运行算子对音频进行格式转换。支持转换为MP3、WAV、FLAC、AAC、OGG等多种格式。

from __future__ import annotations

import os

import daft
from daft import col
from daft.las.functions.audio import AudioConvert
from daft.las.functions.udf import las_udf

if __name__ == "__main__":
    # 转换后的音频会保存到指定的TOS路径下，因此，需要设置好环境变量以保证有权限写入TOS，包括：ACCESS_KEY,SECRET_KEY,TOS_ENDPOINT,TOS_REGION,TOS_TEST_DIR
    TOS_TEST_DIR_URL = os.getenv("TOS_TEST_DIR_URL", "las-cn-beijing-public-online.tos-cn-beijing.volces.com")
    TOS_TEST_DIR = os.getenv("TOS_TEST_DIR", "tos_bucket")

    if os.getenv("DAFT_RUNNER", "native") == "ray":
        import logging

        import ray

        def configure_logging():
            logging.basicConfig(
                level=logging.INFO,
                format="%(asctime)s - %(name)s - %(levelname)s - %(message)s",
                datefmt="%Y-%m-%d %H:%M:%S",
            )
            logging.getLogger("tracing.span").setLevel(logging.WARNING)
            logging.getLogger("daft_io.stats").setLevel(logging.WARNING)
            logging.getLogger("DaftStatisticsManager").setLevel(logging.WARNING)
            logging.getLogger("DaftFlotillaScheduler").setLevel(logging.WARNING)
            logging.getLogger("DaftFlotillaDispatcher").setLevel(logging.WARNING)

        ray.init(dashboard_host="0.0.0.0", runtime_env={"worker_process_setup_hook": configure_logging})
        daft.context.set_runner_ray()

    daft.set_execution_config(actor_udf_ready_timeout=600)
    daft.set_execution_config(min_cpu_per_task=0)

    samples = {
        "input_path": [f"https://{TOS_TEST_DIR_URL}/public/archive/audio_convert/sample.wav"],
        "output_path": [f"tos://{TOS_TEST_DIR}/audio_convert/sample_converted.mp3"],
    }
    ds = daft.from_pydict(samples)

    # Using Daft to convert audio to MP3 format (as an example)
    # AudioConvert supports multiple formats: mp3, wav, flac, aac, ogg, etc.
    constructor_kwargs = {
        "output_format": "mp3",
        "sample_rate": 44100,
        "audio_map": "auto",
        "extra_params": ["-c:a", "libmp3lame", "-b:a", "192k", "-q:a", "2"],
    }

    ds = ds.with_column(
        "convert_result",
        las_udf(
            AudioConvert,
            construct_args=constructor_kwargs,
            num_cpus=1,
            concurrency=1,
            batch_size=1,
        )(col("input_path"), col("output_path")),
    )

    ds.show()
    # ╭────────────────────────────────┬────────────────────────────────┬────────────────────────────────╮
    # │ input_path                     ┆ output_path                    ┆ convert_result                 │
    # │ ---                            ┆ ---                            ┆ ---                            │
    # │ String                         ┆ String                         ┆ String                         │
    # ╞════════════════════════════════╪════════════════════════════════╪════════════════════════════════╡
    # │ https://las-public-data-qa.to… ┆ tos://tos_bucket/audio_conver… ┆ tos://tos_bucket/audio_conver… │
    # ╰────────────────────────────────┴────────────────────────────────┴────────────────────────────────╯