通过 Python Flask 网络服务器播放保存在本地驱动器中的音频文件

Question

当我导航到我的本地磁盘并选择音频 .wav（或任何其他音频类型）文件并点击提交时，我没有得到音频输出。

我正在考虑编写一个 "if statement" 来告诉我的程序何时将所选文件分配给变量 "filename"，然后使用分配的 file/link 重新加载程序。

我对这样的 if 语句做了一些尝试，但由于缺乏编码技能而失败了。

P.S。我提到了 "if statement" 解决方法，因为我认为这就是我的问题的解决方案，否则我意识到我可能有 200% 的错误。

如果可以，请帮助我。谢谢

我的代码：

from __future__ import print_function
from gnuradio import analog
from gnuradio import audio
from gnuradio import blocks
from gnuradio import eng_notation
from gnuradio import gr
from gnuradio.eng_option import eng_option
from gnuradio.filter import firdes
from optparse import OptionParser


class TopBlock22(gr.top_block): 


    def getfile(self, filename):

        gr.top_block.__init__(self, "Top Block 22")

        print('[TopBlock22] getfile: filename:', filename)

        filename = filename.encode('utf-8') 

        self.blocks_file_source_0 = blocks.file_source(gr.sizeof_float*1, filename, True)
        self.audio_sink = audio.sink(32000, '', True)

        ##################################################
        # Connections
        ##################################################
        self.connect((self.blocks_file_source_0, 0), (self.audio_sink, 0))


# -----------------------------------------------------------------------------

from flask import Flask, flash, request, redirect, jsonify, render_template_string


app = Flask(__name__)


tb = TopBlock22()
tb.start()


@app.route("/")
def index():
    args_filename = request.args.get('filename', '')


    return render_template_string('''<!DOCTYPE html>
<html>


<body>

<!-- Previous filename: {{ filename }} -->
<form action="getfile" method="POST" enctype="multipart/form-data">
    Project file path: <input type="file" name="file"><br>
    <input type="submit" value="Submit">
</form>



</body>
</html>''', filename=args_filename)


@app.route('/getfile', methods=['GET','POST'])
def getfile():


    result = request.files.get('file')
    print('[/getfile] result:', result.filename)

    if result:

        result.save(result.filename) 

        tb.getfile(result.filename)



    return redirect('/')



if __name__ == '__main__':
    app.run(host='0.0.0.0', debug=True)

回溯输出（无错误：

 * Serving Flask app "app" (lazy loading)
 * Environment: production
   WARNING: This is a development server. Do not use it in a production deployment.
   Use a production WSGI server instead.
 * Debug mode: on
 * Running on http://0.0.0.0:5000/ (Press CTRL+C to quit)
 * Restarting with stat
 * Debugger is active!
 * Debugger PIN: 138-727-058
127.0.0.1 - - [23/Aug/2019 13:36:47] "GET / HTTP/1.1" 200 -
[/getfile] result: song.wav
[TopBlock22] getfile: filename: song.wav
gr::log :INFO: audio source - Audio sink arch: alsa
127.0.0.1 - - [23/Aug/2019 13:36:52] "POST /getfile HTTP/1.1" 302 -
127.0.0.1 - - [23/Aug/2019 13:36:52] "GET / HTTP/1.1" 200 -

Answer 1

所有示例均未使用 Flask 以更轻松地测试问题。

要从文件中听到声音，我必须在 start()

之前运行 getfile()

from __future__ import print_function
from gnuradio import gr
from gnuradio import audio
from gnuradio import blocks


class TopBlock22(gr.top_block): 

    #def __init__(self):
    #    gr.top_block.__init__(self, "Top Block 22")

    def getfile(self, filename):
        print('[TopBlock22] getfile: filename:', filename)

        filename = filename.encode('utf-8') 

        self.blocks_file_source_0 = blocks.file_source(gr.sizeof_float*1, filename, True)
        self.audio_sink = audio.sink(32000, '', True)

        self.connect((self.blocks_file_source_0, 0), (self.audio_sink, 0))

# -----------------------------------------------------------------------------

tb = TopBlock22()

tb.getfile('song.wav')
tb.start()

tb.wait()

要在 start() 之后使用 getfile() 并听到声音，必须再次 stop() 和 start()。

from __future__ import print_function
from gnuradio import gr
from gnuradio import audio
from gnuradio import blocks


class TopBlock22(gr.top_block): 

    #def __init__(self):
    #    gr.top_block.__init__(self, "Top Block 22")

    def getfile(self, filename):
        print('[TopBlock22] getfile: filename:', filename)

        filename = filename.encode('utf-8') 

        self.blocks_file_source_0 = blocks.file_source(gr.sizeof_float*1, filename, True)
        self.audio_sink = audio.sink(32000, '', True)

        self.connect((self.blocks_file_source_0, 0), (self.audio_sink, 0))

        self.stop()
        self.start()

# -----------------------------------------------------------------------------

tb = TopBlock22()

tb.start()

tb.getfile('song.wav')

tb.wait()

或者必须使用lock(), unlock()

from __future__ import print_function
from gnuradio import gr
from gnuradio import audio
from gnuradio import blocks


class TopBlock22(gr.top_block): 

    #def __init__(self):
    #    gr.top_block.__init__(self, "Top Block 22")

    def getfile(self, filename):
        print('[TopBlock22] getfile: filename:', filename)

        filename = filename.encode('utf-8') 

        self.blocks_file_source_0 = blocks.file_source(gr.sizeof_float*1, filename, True)
        self.audio_sink = audio.sink(32000, '', True)

        self.lock()
        self.connect((self.blocks_file_source_0, 0), (self.audio_sink, 0))
        self.unlock()

# -----------------------------------------------------------------------------

tb = TopBlock22()

tb.start()

tb.getfile('song.wav')

tb.wait()

但这不会在您加载新文件时断开之前的声音。它必须记住是否加载了其他文件并使用 disconnect() 停止之前的声音。

from __future__ import print_function
from gnuradio import gr
from gnuradio import audio
from gnuradio import blocks


class TopBlock22(gr.top_block): 

    def __init__(self):
        gr.top_block.__init__(self, "Top Block 22")

        # at star file is not loaded and not connected
        self.file_source_connected = False

    def getfile(self, filename):
        print('[TopBlock22] getfile: filename:', filename)

        filename = filename.encode('utf-8') 

        ##################################################
        # Connections
        ##################################################

        self.lock()

        # disconnect previous file
        if self.file_source_connected:
            self.disconnect((self.blocks_file_source_0, 0), (self.audio_sink, 0))

        # use new file
        self.blocks_file_source_0 = blocks.file_source(gr.sizeof_float*1, filename, True)
        self.audio_sink = audio.sink(32000, '', True)

        self.connect((self.blocks_file_source_0, 0), (self.audio_sink, 0))

        self.unlock()

        # remember that file is connected
        self.file_source_connected = True


# -----------------------------------------------------------------------------
import time

tb = TopBlock22()
tb.start()

tb.getfile('song.wav') # use one file 
time.sleep(3)
tb.getfile('another_song.wav') # use another file later

tb.wait()

通过 Python Flask 网络服务器播放保存在本地驱动器中的音频文件

play audio file saved in local drive via Python Flask webserver

html

python

gnuradio

flask