#322 sox FAIL noisered: multi-channel effect drained asymmetrically! error

[Kirill Okhotnikov]

Dear SOX developers,

Thank you very much for your excellent program. It is really cool and helps a lot in my project!

I'm trying to use noisered filter for two channels input audio with odd number of samples. I'm getting the error like this sox FAIL noisered: multi-channel effect drained asymmetrically!
As I think the problem is here

./src/noisered.c
...
static int sox_noisered_drain(sox_effect_t * effp, sox_sample_t *obuf, size_t *osamp)
{
    priv_t * data = (priv_t *)effp->priv;
    unsigned i;
    unsigned tracks = effp->in_signal.channels;
    for (i = 0; i < tracks; i ++)
        *osamp = process_window(effp, data, i, tracks, obuf, (unsigned) data->bufdata); // <-- STORE LAST TRACK SAMPLE SIZE!!!!!!!

    /* FIXME: This is very picky.  osamp needs to be big enough to get all

     * remaining data or it will be discarded.
     */
    return (SOX_EOF);
}
...

I can suggest a possible solution, but I'm not sure is it enough or not (I don't familiar with your code).

./src/noisered.c
...
static int sox_noisered_drain(sox_effect_t * effp, sox_sample_t *obuf, size_t *osamp)
{
    priv_t * data = (priv_t *)effp->priv;
    unsigned i;
    unsigned tracks = effp->in_signal.channels;
    *osamp = 0;
    for (i = 0; i < tracks; i ++)
        *osamp += process_window(effp, data, i, tracks, obuf, (unsigned) data->bufdata); // <-- SUM ALL TRACKS SAMPLES

    /* FIXME: This is very picky.  osamp needs to be big enough to get all

     * remaining data or it will be discarded.
     */
    return (SOX_EOF);
}
...

Sincerely yours,
Kirill.

[Martin Guy]

Confirmed. The suggested fix seems correct.
https://codeberg.org/sox_ng/sox_ng/issues/548