jack: add jack_get_video_image_size extension

Add a JACK PipeWire extension to get the video size of the DSP
pipeline and use this instead of the hardcoded values in the example.

pipewire-jack/src/meson.build

@@ -28,5 +28,6 @@ if sdl_dep.found()
     c_args : [ '-D_GNU_SOURCE' ],
     install: false,
     dependencies : [jack_dep, sdl_dep, mathlib],
+    link_with: pipewire_jack,
   )
 endif

pipewire-jack/src/pipewire-jack-extensions.h

@@ -0,0 +1,49 @@
+/* PipeWire JACK extensions
+ *
+ * Copyright © 2020 Wim Taymans
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef PIPEWIRE_JACK_EXTENSIONS_H
+#define PIPEWIRE_JACK_EXTENSIONS_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** 1.0 gamma, full range HDR 0.0 -> 1.0, pre-multiplied
+ * alpha, BT.2020 primaries, progressive */
+#define JACK_DEFAULT_VIDEO_TYPE	"32 bit float RGBA video"
+
+typedef struct jack_image_size {
+	uint32_t width;
+	uint32_t height;
+	uint32_t stride;
+	uint32_t flags;
+} jack_image_size_t;
+
+int jack_get_video_image_size(jack_client_t *client, jack_image_size_t *size);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* PIPEWIRE_JACK_EXTENSIONS_H */

pipewire-jack/src/pipewire-jack.c

@@ -46,6 +46,7 @@
 
 #include "extensions/client-node.h"
 #include "extensions/metadata.h"
+#include "pipewire-jack-extensions.h"
 
 #define JACK_DEFAULT_VIDEO_TYPE	"32 bit float RGBA video"
 
@@ -4342,6 +4343,34 @@ uint32_t jack_midi_get_lost_event_count(void *port_buffer)
 	return mb->lost_events;
 }
 
+/** extensions */
+
+SPA_EXPORT
+int jack_get_video_image_size(jack_client_t *client, jack_image_size_t *size)
+{
+	struct client *c = (struct client *) client;
+	struct pw_node_activation *a = c->driver_activation;
+
+	printf("1\n");
+	if (a == NULL)
+		a = c->activation;
+	if (a == NULL)
+		return -EIO;
+
+	printf("2\n");
+	if (!(a->position.video.flags & SPA_IO_VIDEO_SIZE_VALID))
+		return -EIO;
+
+	printf("3\n");
+	size->width = a->position.video.size.width;
+	size->height = a->position.video.size.height;
+	size->stride = a->position.video.stride;
+	size->flags = 0;
+	printf("%d %d %d %d\n", size->width, size->height, size->stride, size->flags);
+	return size->stride * size->height;
+}
+
+
 static void reg(void) __attribute__ ((constructor));
 static void reg(void)
 {