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/examples/video-dsp-play.c

@@ -29,10 +29,7 @@
 #include <SDL2/SDL.h>
 
 #include <jack/jack.h>
-
-#define WIDTH   320
-#define HEIGHT  240
-#define BPP     16
+#include <pipewire-jack-extensions.h>
 
 #define MAX_BUFFERS	64
 
@@ -62,9 +59,7 @@ struct data {
 	const char *client_name;
 	jack_port_t *in_port;
 
-	uint32_t width;
-	uint32_t height;
-	int32_t stride;
+	jack_image_size_t size;
 
 	int counter;
 	SDL_Rect rect;
@@ -102,14 +97,14 @@ process (jack_nframes_t nframes, void *arg)
 	}
 
 	/* copy video image in texture */
-	sstride = data->stride;
+	sstride = data->size.stride;
 
 	src = sdata;
 	dst = ddata;
 
-	for (i = 0; i < data->height; i++) {
+	for (i = 0; i < data->size.height; i++) {
 		struct pixel *p = (struct pixel *) src;
-		for (j = 0; j < data->width; j++) {
+		for (j = 0; j < data->size.width; j++) {
 			dst[j * 4 + 0] = CLAMP(lrintf(p[j].r * 255.0f), 0, 255);
 			dst[j * 4 + 1] = CLAMP(lrintf(p[j].g * 255.0f), 0, 255);
 			dst[j * 4 + 2] = CLAMP(lrintf(p[j].b * 255.0f), 0, 255);
@@ -133,6 +128,7 @@ int main(int argc, char *argv[])
 	struct data data = { 0, };
 	jack_options_t options = JackNullOption;
         jack_status_t status;
+	int res;
 
 	data.client = jack_client_open ("video-dsp-play", options, &status);
         if (data.client == NULL) {
@@ -153,9 +149,10 @@ int main(int argc, char *argv[])
 
         jack_set_process_callback (data.client, process, &data);
 
-	data.width = WIDTH;
-	data.height = HEIGHT;
-	data.stride = data.width * 4 * sizeof(float);
+	if ((res = jack_get_video_image_size(data.client, &data.size)) < 0) {
+		fprintf(stderr, "can't get video size: %d %s\n", res, strerror(-res));
+		return -1;
+	}
 
 	if (SDL_Init(SDL_INIT_VIDEO) < 0) {
 		fprintf(stderr, "can't initialize SDL: %s\n", SDL_GetError());
@@ -163,7 +160,7 @@ int main(int argc, char *argv[])
 	}
 
 	if (SDL_CreateWindowAndRenderer
-	    (WIDTH, HEIGHT, SDL_WINDOW_RESIZABLE, &data.window, &data.renderer)) {
+	    (data.size.width, data.size.height, SDL_WINDOW_RESIZABLE, &data.window, &data.renderer)) {
 		fprintf(stderr, "can't create window: %s\n", SDL_GetError());
 		return -1;
 	}
@@ -171,12 +168,12 @@ int main(int argc, char *argv[])
 	data.texture = SDL_CreateTexture(data.renderer,
 					  SDL_PIXELFORMAT_RGBA32,
 					  SDL_TEXTUREACCESS_STREAMING,
-					  data.width,
-					  data.height);
+					  data.size.width,
+					  data.size.height);
 	data.rect.x = 0;
 	data.rect.y = 0;
-	data.rect.w = data.width;
-	data.rect.h = data.height;
+	data.rect.w = data.size.width;
+	data.rect.h = data.size.height;
 
 	data.in_port = jack_port_register (data.client, "input",
                                           JACK_DEFAULT_VIDEO_TYPE,

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)
 {