Combiner: input_type not specified

[Viginox]

When using the combiner to build the output file, the Warning
WARNING:root:Input formats were only specified for 0 out of 2 files.The last 2 files will remain unformatted.
will be issued.
As far as I understood the working of combine.py this is because self.input_format is not supposed to be None due to the initialization

self.input_format = []

on line 58 in transform.py
and therefore the if condition

# Adjust length of input_format list
if input_format is None:
    fmts = [[] for _ in range(n_inputs)]

on line 392 in combine.py will never evaluate to True when being called from the build function

input_format_list = _build_input_format_list(
            input_filepath_list, input_volumes, self.input_format
)

( line 75 in combine.py )

Is this behavior on purpose?

[lostanlen]

Hello! Thanks for reporting. What is the minimal code example you could provide that reproduces the issue?

[Viginox]

I tested it with multiple file formats and also with all options for the Combiner.
(In my application I am using flac for both input files)

The minimal application would be as following:

import sox

cbn = sox.Combiner()
cbn.build([input_1, input_2], output_file, "mix-power")

I also tried to edit the code so this warning won't be displayed anymore, but I didn't know, if this behavior is intended.

My fix:

# Adjust length of input_format list
if input_format is None or input_format == []:

( line 392 in combine.py )

[spolezhaev]

Has the same issue. Obviously, it can be fixed by cbn.set_input_format(file_type=['wav', 'wav']) before build, but it works perfectly even without this line (showing this annoying message). Please add an option to suppress warning messages.

[jackkinsella]

Same issue.