1 files changed, 47 insertions, 4 deletions

diff --git a/src/gstreamer/gstlibcamera-utils.cpp b/src/gstreamer/gstlibcamera-utils.cpp
index f7e0e1c8..0af91c1a 100644
--- a/src/gstreamer/gstlibcamera-utils.cpp
+++ b/src/gstreamer/gstlibcamera-utils.cpp
@@ -136,14 +136,57 @@ gst_libcamera_configure_stream_from_caps(StreamConfiguration &stream_cfg,
 					 GstCaps *caps)
 {
 	GstVideoFormat gst_format = pixel_format_to_gst_format(stream_cfg.pixelFormat);
+	guint i;
+	gint best_fixed = -1, best_in_range = -1;
+	GstStructure *s;
+
+	/*
+	 * These are delta weight computed from:
+	 *   ABS(width - stream_cfg.size.width) * ABS(height - stream_cfg.size.height)
+	 */
+	guint best_fixed_delta = G_MAXUINT;
+	guint best_in_range_delta = G_MAXUINT;
 
 	/* First fixate the caps using default configuration value. */
 	g_assert(gst_caps_is_writable(caps));
-	caps = gst_caps_truncate(caps);
-	GstStructure *s = gst_caps_get_structure(caps, 0);
 
-	gst_structure_fixate_field_nearest_int(s, "width", stream_cfg.size.width);
-	gst_structure_fixate_field_nearest_int(s, "height", stream_cfg.size.height);
+	/* Lookup the structure for a close match to the stream_cfg.size */
+	for (i = 0; i < gst_caps_get_size(caps); i++) {
+		s = gst_caps_get_structure(caps, i);
+		gint width, height;
+		guint delta;
+
+		if (gst_structure_has_field_typed(s, "width", G_TYPE_INT) &&
+		    gst_structure_has_field_typed(s, "height", G_TYPE_INT)) {
+			gst_structure_get_int(s, "width", &width);
+			gst_structure_get_int(s, "height", &height);
+
+			delta = ABS(width - (gint)stream_cfg.size.width) * ABS(height - (gint)stream_cfg.size.height);
+
+			if (delta < best_fixed_delta) {
+				best_fixed_delta = delta;
+				best_fixed = i;
+			}
+		} else {
+			gst_structure_fixate_field_nearest_int(s, "width", stream_cfg.size.width);
+			gst_structure_fixate_field_nearest_int(s, "height", stream_cfg.size.height);
+			gst_structure_get_int(s, "width", &width);
+			gst_structure_get_int(s, "height", &height);
+
+			delta = ABS(width - (gint)stream_cfg.size.width) * ABS(height - (gint)stream_cfg.size.height);
+
+			if (delta < best_in_range_delta) {
+				best_in_range_delta = delta;
+				best_in_range = i;
+			}
+		}
+	}
+
+	/* Prefer reliable fixed value over ranges */
+	if (best_fixed >= 0)
+		s = gst_caps_get_structure(caps, best_fixed);
+	else
+		s = gst_caps_get_structure(caps, best_in_range);
 
 	if (gst_structure_has_name(s, "video/x-raw")) {
 		const gchar *format = gst_video_format_to_string(gst_format);