[GStreamer][WebRTC] Apply platform-specific quirks for incoming tracks

https://bugs.webkit.org/show_bug.cgi?id=276769

Reviewed by Xabier Rodriguez-Calvar.

On platforms where quirks are required, keep hardware-accelerated parsers out of the WebRTC
pipeline. They are instead used from the playback pipeline. The LibWebRTC backend had support for
this already, this patch brings the same feature to the GstWebRTC backend.

* Source/WebCore/platform/graphics/gstreamer/GStreamerCommon.cpp:
(WebCore::gstGetAutoplugSelectResult):
* Source/WebCore/platform/graphics/gstreamer/GStreamerCommon.h:
* Source/WebCore/platform/mediastream/gstreamer/GStreamerIncomingTrackProcessor.cpp:
(WebCore::GStreamerIncomingTrackProcessor::createParser):
* Source/WebCore/platform/mediastream/libwebrtc/gstreamer/GStreamerVideoDecoderFactory.cpp:
(WebCore::GStreamerWebRTCVideoDecoder::getGstAutoplugSelectResult): Deleted.

Canonical link: https://commits.webkit.org/281292@main

Author: philn

Source/WebCore/platform/graphics/gstreamer/GStreamerCommon.cpp

@@ -1005,6 +1005,18 @@ bool gstObjectHasProperty(GstPad* pad, const char* name)
     return gstObjectHasProperty(GST_OBJECT_CAST(pad), name);
 }
 
+std::optional<unsigned> gstGetAutoplugSelectResult(ASCIILiteral nick)
+{
+    static auto enumClass = static_cast<GEnumClass*>(g_type_class_ref(g_type_from_name("GstAutoplugSelectResult")));
+    RELEASE_ASSERT(enumClass);
+    auto enumValue = g_enum_get_value_by_nick(enumClass, nick.characters());
+    if (!enumValue)
+        return std::nullopt;
+    return enumValue->value;
+}
+
+#undef GST_CAT_DEFAULT
+
 } // namespace WebCore
 
 #if !GST_CHECK_VERSION(1, 20, 0)

Source/WebCore/platform/graphics/gstreamer/GStreamerCommon.h

@@ -409,6 +409,8 @@ void configureVideoRTPDepayloader(GstElement*);
 bool gstObjectHasProperty(GstElement*, const char* name);
 bool gstObjectHasProperty(GstPad*, const char* name);
 
+std::optional<unsigned> gstGetAutoplugSelectResult(ASCIILiteral);
+
 void registerActivePipeline(const GRefPtr<GstElement>&);
 void unregisterPipeline(const GRefPtr<GstElement>&);
 

Source/WebCore/platform/mediastream/gstreamer/GStreamerIncomingTrackProcessor.cpp

@@ -22,6 +22,7 @@
 #if USE(GSTREAMER_WEBRTC)
 
 #include "GStreamerCommon.h"
+#include "GStreamerQuirks.h"
 #include "GStreamerRegistryScanner.h"
 
 GST_DEBUG_CATEGORY(webkit_webrtc_incoming_track_processor_debug);
@@ -244,6 +245,22 @@ GRefPtr<GstElement> GStreamerIncomingTrackProcessor::createParser()
         configureVideoRTPDepayloader(element);
     }), nullptr);
 
+    auto& quirksManager = GStreamerQuirksManager::singleton();
+    if (quirksManager.isEnabled()) {
+        // Prevent auto-plugging of hardware-accelerated elements. Those will be used in the playback pipeline.
+        g_signal_connect(parsebin.get(), "autoplug-select", G_CALLBACK(+[](GstElement*, GstPad*, GstCaps*, GstElementFactory* factory, gpointer) -> unsigned {
+            static auto skipAutoPlug = gstGetAutoplugSelectResult("skip"_s);
+            static auto tryAutoPlug = gstGetAutoplugSelectResult("try"_s);
+            RELEASE_ASSERT(skipAutoPlug);
+            RELEASE_ASSERT(tryAutoPlug);
+            auto& quirksManager = GStreamerQuirksManager::singleton();
+            auto isHardwareAccelerated = quirksManager.isHardwareAccelerated(factory).value_or(false);
+            if (isHardwareAccelerated)
+                return *skipAutoPlug;
+            return *tryAutoPlug;
+        }), nullptr);
+    }
+
     g_signal_connect_swapped(parsebin.get(), "pad-added", G_CALLBACK(+[](GStreamerIncomingTrackProcessor* self, GstPad* pad) {
         auto queue = adoptGRef(gst_bin_get_by_name(GST_BIN_CAST(self->m_bin.get()), "queue"));
         auto sinkPad = adoptGRef(gst_element_get_static_pad(queue.get(), "sink"));

Source/WebCore/platform/mediastream/libwebrtc/gstreamer/GStreamerVideoDecoderFactory.cpp

@@ -83,16 +83,6 @@ class GStreamerWebRTCVideoDecoder : public webrtc::VideoDecoder {
         m_needsKeyframe = true;
     }
 
-    static unsigned getGstAutoplugSelectResult(const char* nick)
-    {
-        static GEnumClass* enumClass = static_cast<GEnumClass*>(g_type_class_ref(g_type_from_name("GstAutoplugSelectResult")));
-        ASSERT(enumClass);
-        GEnumValue* ev = g_enum_get_value_by_nick(enumClass, nick);
-        if (!ev)
-            return 0;
-        return ev->value;
-    }
-
     bool Configure(const webrtc::VideoDecoder::Settings& codecSettings) override
     {
         m_src = makeElement("appsrc");
@@ -112,12 +102,17 @@ class GStreamerWebRTCVideoDecoder : public webrtc::VideoDecoder {
 
         auto& quirksManager = GStreamerQuirksManager::singleton();
         if (quirksManager.isEnabled()) {
+            // Prevent auto-plugging of hardware-accelerated elements. Those will be used in the playback pipeline.
             g_signal_connect(decoder, "autoplug-select", G_CALLBACK(+[](GstElement*, GstPad*, GstCaps*, GstElementFactory* factory, gpointer) -> unsigned {
+                static auto skipAutoPlug = gstGetAutoplugSelectResult("skip"_s);
+                static auto tryAutoPlug = gstGetAutoplugSelectResult("try"_s);
+                RELEASE_ASSERT(skipAutoPlug);
+                RELEASE_ASSERT(tryAutoPlug);
                 auto& quirksManager = GStreamerQuirksManager::singleton();
                 auto isHardwareAccelerated = quirksManager.isHardwareAccelerated(factory).value_or(false);
                 if (isHardwareAccelerated)
-                    return getGstAutoplugSelectResult("skip");
-                return getGstAutoplugSelectResult("try");
+                    return *skipAutoPlug;
+                return *tryAutoPlug;
             }), nullptr);
         }