libs: audio: split allocation query caps and pad caps

Since the allocation query caps contains memory size and the pad's caps
contains the display size, an audio encoder or decoder might need to allocate
a different buffer size than the size negotiated in the caps.

This patch splits this logic distinction for audiodecoder and audioencoder.

Thus the user, if needs a different allocation caps, should set it through
gst_audio_{encoder,decoder}_set_allocation_cap() before calling the negotiate()
vmethod. Otherwise the allocation_caps will be the same as the caps in the
src pad.

https://bugzilla.gnome.org/show_bug.cgi?id=764421

gst-libs/gst/audio/gstaudiodecoder.c

@@ -203,6 +203,7 @@ typedef struct _GstAudioDecoderContext
   gboolean do_plc;
   gboolean do_estimate_rate;
   gint max_errors;
+  GstCaps *allocation_caps;
   /* MT-protected (with LOCK) */
   GstClockTime min_latency;
   GstClockTime max_latency;
@@ -525,6 +526,7 @@ gst_audio_decoder_reset (GstAudioDecoder * dec, gboolean full)
       gst_object_unref (dec->priv->ctx.allocator);
 
     gst_caps_replace (&dec->priv->ctx.input_caps, NULL);
+    gst_caps_replace (&dec->priv->ctx.allocation_caps, NULL);
 
     memset (&dec->priv->ctx, 0, sizeof (dec->priv->ctx));
 
@@ -639,6 +641,8 @@ gst_audio_decoder_negotiate_default (GstAudioDecoder * dec)
   klass = GST_AUDIO_DECODER_GET_CLASS (dec);
 
   caps = gst_audio_info_to_caps (&dec->priv->ctx.info);
+  if (dec->priv->ctx.allocation_caps == NULL)
+    dec->priv->ctx.allocation_caps = gst_caps_ref (caps);
 
   GST_DEBUG_OBJECT (dec, "setting src caps %" GST_PTR_FORMAT, caps);
 
@@ -673,7 +677,7 @@ gst_audio_decoder_negotiate_default (GstAudioDecoder * dec)
     goto done;
   dec->priv->ctx.output_format_changed = FALSE;
 
-  query = gst_query_new_allocation (caps, TRUE);
+  query = gst_query_new_allocation (dec->priv->ctx.allocation_caps, TRUE);
   if (!gst_pad_peer_query (dec->srcpad, query)) {
     GST_DEBUG_OBJECT (dec, "didn't get downstream ALLOCATION hints");
   }
@@ -3265,6 +3269,27 @@ gst_audio_decoder_get_parse_state (GstAudioDecoder * dec,
     *eos = dec->priv->ctx.eos;
 }
 
+/**
+ * gst_audio_decoder_set_allocation_caps:
+ * @dec: a #GstAudioDecoder
+ * @allocation_caps: (allow-none): a #GstCaps or %NULL
+ *
+ * Sets a caps in allocation query which are different from the set
+ * pad's caps. Use this function before calling
+ * gst_audio_decoder_negotiate(). Setting to %NULL the allocation
+ * query will use the caps from the pad.
+ *
+ * Since: 1.10
+ */
+void
+gst_audio_decoder_set_allocation_caps (GstAudioDecoder * dec,
+    GstCaps * allocation_caps)
+{
+  g_return_if_fail (GST_IS_AUDIO_DECODER (dec));
+
+  gst_caps_replace (&dec->priv->ctx.allocation_caps, allocation_caps);
+}
+
 /**
  * gst_audio_decoder_set_plc:
  * @dec: a #GstAudioDecoder

gst-libs/gst/audio/gstaudiodecoder.h

@@ -360,6 +360,8 @@ void              gst_audio_decoder_get_parse_state (GstAudioDecoder * dec,
                                                      gboolean        * sync,
                                                      gboolean        * eos);
 
+void              gst_audio_decoder_set_allocation_caps (GstAudioDecoder * dec,
+                                                         GstCaps         * allocation_caps);
 
 /* object properties */
 void              gst_audio_decoder_set_plc (GstAudioDecoder * dec,

gst-libs/gst/audio/gstaudioencoder.c

@@ -194,6 +194,7 @@ typedef struct _GstAudioEncoderContext
 
   /* output */
   GstCaps *caps;
+  GstCaps *allocation_caps;
   gboolean output_caps_changed;
   gint frame_samples_min, frame_samples_max;
   gint frame_max;
@@ -492,6 +493,7 @@ gst_audio_encoder_reset (GstAudioEncoder * enc, gboolean full)
 
     gst_caps_replace (&enc->priv->ctx.input_caps, NULL);
     gst_caps_replace (&enc->priv->ctx.caps, NULL);
+    gst_caps_replace (&enc->priv->ctx.allocation_caps, NULL);
 
     memset (&enc->priv->ctx, 0, sizeof (enc->priv->ctx));
     gst_audio_info_init (&enc->priv->ctx.info);
@@ -2386,6 +2388,27 @@ gst_audio_encoder_set_headers (GstAudioEncoder * enc, GList * headers)
   enc->priv->ctx.new_headers = TRUE;
 }
 
+/**
+ * gst_audio_encoder_set_allocation_caps:
+ * @enc: a #GstAudioEncoder
+ * @allocation_caps: (allow-none): a #GstCaps or %NULL
+ *
+ * Sets a caps in allocation query which are different from the set
+ * pad's caps. Use this function before calling
+ * gst_audio_encoder_negotiate(). Setting to %NULL the allocation
+ * query will use the caps from the pad.
+ *
+ * Since: 1.10
+ */
+void
+gst_audio_encoder_set_allocation_caps (GstAudioEncoder * enc,
+    GstCaps * allocation_caps)
+{
+  g_return_if_fail (GST_IS_AUDIO_ENCODER (enc));
+
+  gst_caps_replace (&enc->priv->ctx.allocation_caps, allocation_caps);
+}
+
 /**
  * gst_audio_encoder_set_mark_granule:
  * @enc: a #GstAudioEncoder
@@ -2717,6 +2740,8 @@ gst_audio_encoder_negotiate_default (GstAudioEncoder * enc)
   klass = GST_AUDIO_ENCODER_GET_CLASS (enc);
 
   caps = enc->priv->ctx.caps;
+  if (enc->priv->ctx.allocation_caps == NULL)
+    enc->priv->ctx.allocation_caps = gst_caps_ref (caps);
 
   GST_DEBUG_OBJECT (enc, "Setting srcpad caps %" GST_PTR_FORMAT, caps);
 
@@ -2751,7 +2776,7 @@ gst_audio_encoder_negotiate_default (GstAudioEncoder * enc)
     goto done;
   enc->priv->ctx.output_caps_changed = FALSE;
 
-  query = gst_query_new_allocation (caps, TRUE);
+  query = gst_query_new_allocation (enc->priv->ctx.allocation_caps, TRUE);
   if (!gst_pad_peer_query (enc->srcpad, query)) {
     GST_DEBUG_OBJECT (enc, "didn't get downstream ALLOCATION hints");
   }

gst-libs/gst/audio/gstaudioencoder.h

@@ -295,6 +295,9 @@ void            gst_audio_encoder_set_latency (GstAudioEncoder * enc,
 void            gst_audio_encoder_set_headers (GstAudioEncoder * enc,
                                                GList           * headers);
 
+void            gst_audio_encoder_set_allocation_caps (GstAudioEncoder * enc,
+                                                       GstCaps         * allocation_caps);
+
 /* object properties */
 
 void            gst_audio_encoder_set_mark_granule (GstAudioEncoder * enc,