osxaudio: fixes playback of mono streams with no channel-mask field in caps

Fixes a negotiation error seen when trying to playback of a .MOV file with
a mono AAC audio stream decoded by avcdec_aac that doesn't set channel-mask
field but sink was requiring channel-mask=0x3.
This commit is contained in:
Josep Torra 2017-05-20 17:09:52 +02:00
parent de3e54690b
commit d699dc615e

View file

@ -644,24 +644,33 @@ gst_core_audio_probe_caps (GstCoreAudio * core_audio, GstCaps * in_caps)
* e.g. if you push 5.1-surround audio to a stereo configuration,
* the left and right channels will be played accordingly,
* and the rest will be dropped. */
if (channels == 1 || (channels == 2 &&
(channel_mask == 0 || channel_mask == STEREO_CHANNEL_MASK))) {
if (channels == 1) {
/* If have mono, then also offer stereo since CoreAudio downmixes to it */
GstStructure *stereo = gst_structure_copy (out_s);
gst_structure_remove_field (out_s, "channel-mask");
gst_structure_set (stereo, "channels", G_TYPE_INT, 2,
"channel-mask", GST_TYPE_BITMASK, STEREO_CHANNEL_MASK, NULL);
gst_caps_append_structure (caps, stereo);
gst_caps_append_structure (caps, out_s);
} else if (channels == 2 && (channel_mask == 0
|| channel_mask == STEREO_CHANNEL_MASK)) {
/* If have stereo channels, then also offer mono since CoreAudio
* upmixes it. If mono, then also offer stereo since CoreAudio
* downmixes to it */
* upmixes it. */
GstStructure *mono = gst_structure_copy (out_s);
gst_structure_set (mono, "channels", G_TYPE_INT, 1, NULL);
gst_structure_remove_field (mono, "channel-mask");
gst_structure_set (out_s, "channel-mask", GST_TYPE_BITMASK,
STEREO_CHANNEL_MASK, NULL);
gst_structure_set (out_s, "channels", GST_TYPE_INT_RANGE, 1, 2, NULL);
if (channels == 1)
gst_structure_set (out_s, "channel-mask", GST_TYPE_BITMASK,
STEREO_CHANNEL_MASK, NULL);
gst_caps_append_structure (caps, out_s);
gst_caps_append_structure (caps, mono);
} else {
/* Otherwhise just add the caps */
gst_caps_append_structure (caps, out_s);
}
gst_caps_append_structure (caps, out_s);
}
}
GST_DEBUG_OBJECT (core_audio, "Probed caps:%" GST_PTR_FORMAT, caps);
return caps;
}