From 0488976dd6e107d1d04e68c5610f6a4f7400a483 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Miroslav=20=C5=A0ediv=C3=BD?= <sedivy.miro@gmail.com>
Date: Sat, 10 Sep 2022 23:18:16 +0200
Subject: [PATCH] gstreamer add API.

---
 pkg/gst/gst.c  | 49 ++++++++++++++++++++++++++++++++++++++++++++++++-
 pkg/gst/gst.go | 48 +++++++++++++++++++++++++++++++++++++++++++++++-
 pkg/gst/gst.h  |  4 ++++
 3 files changed, 99 insertions(+), 2 deletions(-)

diff --git a/pkg/gst/gst.c b/pkg/gst/gst.c
index 1bc9cab8..edcc4a29 100644
--- a/pkg/gst/gst.c
+++ b/pkg/gst/gst.c
@@ -47,7 +47,7 @@ static gboolean gstreamer_bus_call(GstBus *bus, GstMessage *msg, gpointer user_d
       gstreamer_pipeline_log(ctx, "debug",
         "got tags from element %s",
           GST_OBJECT_NAME(msg->src));
-  
+
       gst_tag_list_unref(tags);
       break;
     }
@@ -163,3 +163,50 @@ void gstreamer_pipeline_push(GstPipelineCtx *ctx, void *buffer, int bufferLen) {
     gst_app_src_push_buffer(GST_APP_SRC(ctx->appsrc), buffer);
   }
 }
+
+gboolean gstreamer_pipeline_set_prop_int(GstPipelineCtx *ctx, char *binName, char *prop, gint value) {
+  GstElement *el = gst_bin_get_by_name(GST_BIN(ctx->pipeline), binName);
+  if (el == NULL) return FALSE;
+
+  g_object_set(G_OBJECT(el),
+    prop, value,
+    NULL);
+
+  gst_object_unref(el);
+  return TRUE;
+}
+
+gboolean gstreamer_pipeline_set_caps_framerate(GstPipelineCtx *ctx, const gchar* binName, gint numerator, gint denominator) {
+  GstElement *el = gst_bin_get_by_name(GST_BIN(ctx->pipeline), binName);
+  if (el == NULL) return FALSE;
+
+  GstCaps *caps = gst_caps_new_simple("video/x-raw",
+    "framerate", GST_TYPE_FRACTION, numerator, denominator,
+    NULL);
+
+  g_object_set(G_OBJECT(el),
+    "caps", caps,
+    NULL);
+
+  gst_caps_unref(caps);
+  gst_object_unref(el);
+  return TRUE;
+}
+
+gboolean gstreamer_pipeline_set_caps_resolution(GstPipelineCtx *ctx, const gchar* binName, gint width, gint height) {
+  GstElement *el = gst_bin_get_by_name(GST_BIN(ctx->pipeline), binName);
+  if (el == NULL) return FALSE;
+
+  GstCaps *caps = gst_caps_new_simple("video/x-raw",
+    "width", G_TYPE_INT, width,
+    "height", G_TYPE_INT, height,
+    NULL);
+
+  g_object_set(G_OBJECT(el),
+    "caps", caps,
+    NULL);
+
+  gst_caps_unref(caps);
+  gst_object_unref(el);
+  return TRUE;
+}
diff --git a/pkg/gst/gst.go b/pkg/gst/gst.go
index 80498dcb..e98d80fd 100644
--- a/pkg/gst/gst.go
+++ b/pkg/gst/gst.go
@@ -21,6 +21,7 @@ import (
 
 type Pipeline struct {
 	id     int
+	logger zerolog.Logger
 	Src    string
 	Ctx    *C.GstPipelineCtx
 	Sample chan types.Sample
@@ -56,7 +57,11 @@ func CreatePipeline(pipelineStr string) (*Pipeline, error) {
 	}
 
 	p := &Pipeline{
-		id:     int(id),
+		id: int(id),
+		logger: log.With().
+			Str("module", "capture").
+			Str("submodule", "gstreamer").
+			Int("pipeline_id", int(id)).Logger(),
 		Src:    pipelineStr,
 		Ctx:    ctx,
 		Sample: make(chan types.Sample),
@@ -107,6 +112,47 @@ func (p *Pipeline) Push(buffer []byte) {
 	C.gstreamer_pipeline_push(p.Ctx, bytes, C.int(len(buffer)))
 }
 
+func (p *Pipeline) SetPropInt(binName string, prop string, value int) bool {
+	cBinName := C.CString(binName)
+	defer C.free(unsafe.Pointer(cBinName))
+
+	cProp := C.CString(prop)
+	defer C.free(unsafe.Pointer(cProp))
+
+	cValue := C.int(value)
+
+	p.logger.Debug().Msgf("setting prop %s of %s to %d", prop, binName, value)
+
+	ok := C.gstreamer_pipeline_set_prop_int(p.Ctx, cBinName, cProp, cValue)
+	return ok == C.TRUE
+}
+
+func (p *Pipeline) SetCapsFramerate(binName string, numerator, denominator int) bool {
+	cBinName := C.CString(binName)
+	cNumerator := C.int(numerator)
+	cDenominator := C.int(denominator)
+
+	defer C.free(unsafe.Pointer(cBinName))
+
+	p.logger.Debug().Msgf("setting caps framerate of %s to %d/%d", binName, numerator, denominator)
+
+	ok := C.gstreamer_pipeline_set_caps_framerate(p.Ctx, cBinName, cNumerator, cDenominator)
+	return ok == C.TRUE
+}
+
+func (p *Pipeline) SetCapsResolution(binName string, width, height int) bool {
+	cBinName := C.CString(binName)
+	cWidth := C.int(width)
+	cHeight := C.int(height)
+
+	defer C.free(unsafe.Pointer(cBinName))
+
+	p.logger.Debug().Msgf("setting caps resolution of %s to %dx%d", binName, width, height)
+
+	ok := C.gstreamer_pipeline_set_caps_resolution(p.Ctx, cBinName, cWidth, cHeight)
+	return ok == C.TRUE
+}
+
 // gst-inspect-1.0
 func CheckPlugins(plugins []string) error {
 	var plugin *C.GstPlugin
diff --git a/pkg/gst/gst.h b/pkg/gst/gst.h
index f2af6a2e..64598569 100644
--- a/pkg/gst/gst.h
+++ b/pkg/gst/gst.h
@@ -22,5 +22,9 @@ void gstreamer_pipeline_pause(GstPipelineCtx *ctx);
 void gstreamer_pipeline_destory(GstPipelineCtx *ctx);
 void gstreamer_pipeline_push(GstPipelineCtx *ctx, void *buffer, int bufferLen);
 
+gboolean gstreamer_pipeline_set_prop_int(GstPipelineCtx *ctx, char *binName, char *prop, gint value);
+gboolean gstreamer_pipeline_set_caps_framerate(GstPipelineCtx *ctx, const gchar* binName, gint numerator, gint denominator);
+gboolean gstreamer_pipeline_set_caps_resolution(GstPipelineCtx *ctx, const gchar* binName, gint width, gint height);
+
 void gstreamer_init(void);
 void gstreamer_loop(void);