source: build/lib/media_conv/conversion.py @ 4698

# -*- coding: utf-8 -*-
__author__ = 'sanmai'

import subprocess
import os
import tempfile
import pprint

import logging

logger = logging.getLogger('waitress')


def get_full_ffmpeg_command(ffmpeg_command, input_mime_type, output_mime_type, output_media_file_path):
    full_ffmpeg_command = None

    if input_mime_type == "audio/x-wav" and output_mime_type == "audio/mp4":
        full_ffmpeg_command = [ffmpeg_command,
                               "-i", "pipe:0",
                               "-c:a", "libfdk_aac",
                               "-b:a", "128k",
                               "-nostdin", "-y",
                               output_media_file_path]

    if full_ffmpeg_command is not None:
        logger.debug("full ffmpeg command: " +
                     " ".join(full_ffmpeg_command))

        return full_ffmpeg_command
    else:
        raise NotImplementedError()


def convert(input_media_data,
            input_mime_type,
            output_mime_type,
            temp_directory_path,
            ffmpeg_command):
    try:
        output_media_file_fd, output_media_file_path = tempfile.mkstemp(dir=temp_directory_path,
                                                                        suffix=".m4a")
        os.close(output_media_file_fd)

        full_ffmpeg_command = get_full_ffmpeg_command(ffmpeg_command,
                                                      input_mime_type,
                                                      output_mime_type,
                                                      output_media_file_path)

        with subprocess.Popen(full_ffmpeg_command,
                              stdin=subprocess.PIPE,
                              shell=False,
                              universal_newlines=False) as process_obj:
            try:
                process_obj.stdin.write(input_media_data)
                process_obj.stdin.flush()
                process_obj.stdin.close()

                #stdout_data, stderr_data = process.communicate(input_media_data)

            except subprocess.TimeoutExpired as e:
                process_obj.kill()
                logger.error("ffmpeg process timed out: "
                             + pprint.pprint(e))
                raise
            else:
                try:
                    with open(output_media_file_path,
                              'rb') as output_media_file:
                        output_media_file_data = output_media_file.read()

                        try:
                            os.remove(output_media_file_path)
                        except OSError as e:
                            logger.error("Output media file at '{0}' could not be deleted after ffmpeg process.".format(
                                output_media_file_path) + pprint.pprint(e))
                            raise
                        else:
                            return output_media_file_data
                except OSError as e:
                    logger.error("Output media file at '{0}' could not be read after ffmpeg process.".format(
                        output_media_file_path) + pprint.pprint(e))
                    raise
    except Exception as e:
        logger.error("Output media file at could not be created before "
                     "ffmpeg process." + pprint.pprint(e))
        raise


class Converter(object):
    def __init__(self,
                 caching,
                 ffmpeg_command):

        self.caching = caching
        self.temp_directory_path = tempfile.mkdtemp(suffix='',
                                                    prefix='media_conv__cache__')
        self.ffmpeg_command = ffmpeg_command

        if self.caching:
            import media_conv.cache

    def convert_media_file(self,
                           input_media_data,
                           input_mime_type,
                           output_mime_type):
        if self.caching:
            logger.debug("Caching is enabled.")
            raise NotImplementedError
        else:
            output_media_data = convert(input_media_data=input_media_data,
                                        input_mime_type=input_mime_type,
                                        output_mime_type=output_mime_type,
                                        temp_directory_path=self.temp_directory_path,
                                        ffmpeg_command=self.ffmpeg_command)

            return output_media_data