1 files changed, 438 insertions, 0 deletions
diff --git a/src/examples/video-play-reneg.c b/src/examples/video-play-reneg.c
new file mode 100644
index 0000000..26b19cb
--- /dev/null
+++ b/src/examples/video-play-reneg.c
@@ -0,0 +1,438 @@
+/* PipeWire
+ *
+ * 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.
+ */
+
+/*
+ [title]
+ Video input stream using \ref pw_stream "pw_stream", with format renegotiation.
+ [title]
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <signal.h>
+
+#include <spa/utils/result.h>
+#include <spa/param/video/format-utils.h>
+#include <spa/param/props.h>
+#include <spa/debug/format.h>
+
+#include <pipewire/pipewire.h>
+
+#define WIDTH   640
+#define HEIGHT  480
+
+#define MAX_BUFFERS	64
+
+#include "sdl.h"
+
+struct pixel {
+	float r, g, b, a;
+};
+
+struct data {
+	const char *path;
+
+	SDL_Renderer *renderer;
+	SDL_Window *window;
+	SDL_Texture *texture;
+	SDL_Texture *cursor;
+
+	struct pw_main_loop *loop;
+	struct spa_source *timer;
+
+	struct pw_stream *stream;
+	struct spa_hook stream_listener;
+
+	struct spa_video_info format;
+	int32_t stride;
+	struct spa_rectangle size;
+
+	int counter;
+};
+
+static void handle_events(struct data *data)
+{
+	SDL_Event event;
+	while (SDL_PollEvent(&event)) {
+		switch (event.type) {
+		case SDL_QUIT:
+			pw_main_loop_quit(data->loop);
+			break;
+		}
+	}
+}
+
+/* our data processing function is in general:
+ *
+ *  struct pw_buffer *b;
+ *  b = pw_stream_dequeue_buffer(stream);
+ *
+ *  .. do stuff with buffer ...
+ *
+ *  pw_stream_queue_buffer(stream, b);
+ */
+static void
+on_process(void *_data)
+{
+	struct data *data = _data;
+	struct pw_stream *stream = data->stream;
+	struct pw_buffer *b;
+	struct spa_buffer *buf;
+	void *sdata, *ddata;
+	int sstride, dstride, ostride;
+	uint32_t i;
+	uint8_t *src, *dst;
+
+	b = NULL;
+	/* dequeue and queue old buffers, use the last available
+	 * buffer */
+	while (true) {
+		struct pw_buffer *t;
+		if ((t = pw_stream_dequeue_buffer(stream)) == NULL)
+			break;
+		if (b)
+			pw_stream_queue_buffer(stream, b);
+		b = t;
+	}
+	if (b == NULL) {
+		pw_log_warn("out of buffers: %m");
+		return;
+	}
+
+	buf = b->buffer;
+
+	pw_log_info("new buffer %p", buf);
+
+	handle_events(data);
+
+	if ((sdata = buf->datas[0].data) == NULL)
+		goto done;
+
+	if (SDL_LockTexture(data->texture, NULL, &ddata, &dstride) < 0) {
+		fprintf(stderr, "Couldn't lock texture: %s\n", SDL_GetError());
+		goto done;
+	}
+
+	/* copy video image in texture */
+	sstride = buf->datas[0].chunk->stride;
+	if (sstride == 0)
+		sstride = buf->datas[0].chunk->size / data->size.height;
+	ostride = SPA_MIN(sstride, dstride);
+
+	src = sdata;
+	dst = ddata;
+
+	for (i = 0; i < data->size.height; i++) {
+		memcpy(dst, src, ostride);
+		src += sstride;
+		dst += dstride;
+	}
+	SDL_UnlockTexture(data->texture);
+
+	SDL_RenderClear(data->renderer);
+	/* now render the video */
+	SDL_RenderCopy(data->renderer, data->texture, NULL, NULL);
+	SDL_RenderPresent(data->renderer);
+
+      done:
+	pw_stream_queue_buffer(stream, b);
+}
+
+static void on_stream_state_changed(void *_data, enum pw_stream_state old,
+				    enum pw_stream_state state, const char *error)
+{
+	struct data *data = _data;
+	fprintf(stderr, "stream state: \"%s\"\n", pw_stream_state_as_string(state));
+	switch (state) {
+	case PW_STREAM_STATE_UNCONNECTED:
+		pw_main_loop_quit(data->loop);
+		break;
+	case PW_STREAM_STATE_PAUSED:
+		pw_loop_update_timer(pw_main_loop_get_loop(data->loop),
+				data->timer, NULL, NULL, false);
+		break;
+	case PW_STREAM_STATE_STREAMING:
+	{
+		struct timespec timeout, interval;
+
+		timeout.tv_sec = 1;
+		timeout.tv_nsec = 0;
+		interval.tv_sec = 1;
+		interval.tv_nsec = 0;
+
+		pw_loop_update_timer(pw_main_loop_get_loop(data->loop),
+				data->timer, &timeout, &interval, false);
+		break;
+	}
+	default:
+		break;
+	}
+}
+
+/* Be notified when the stream param changes. We're only looking at the
+ * format changes.
+ *
+ * We are now supposed to call pw_stream_finish_format() with success or
+ * failure, depending on if we can support the format. Because we gave
+ * a list of supported formats, this should be ok.
+ *
+ * As part of pw_stream_finish_format() we can provide parameters that
+ * will control the buffer memory allocation. This includes the metadata
+ * that we would like on our buffer, the size, alignment, etc.
+ */
+static void
+on_stream_param_changed(void *_data, uint32_t id, const struct spa_pod *param)
+{
+	struct data *data = _data;
+	struct pw_stream *stream = data->stream;
+	uint8_t params_buffer[1024];
+	struct spa_pod_builder b = SPA_POD_BUILDER_INIT(params_buffer, sizeof(params_buffer));
+	const struct spa_pod *params[1];
+	Uint32 sdl_format;
+	void *d;
+
+	/* NULL means to clear the format */
+	if (param == NULL || id != SPA_PARAM_Format)
+		return;
+
+	fprintf(stderr, "got format:\n");
+	spa_debug_format(2, NULL, param);
+
+	if (spa_format_parse(param, &data->format.media_type, &data->format.media_subtype) < 0)
+		return;
+
+	if (data->format.media_type != SPA_MEDIA_TYPE_video ||
+	    data->format.media_subtype != SPA_MEDIA_SUBTYPE_raw)
+		return;
+
+	/* call a helper function to parse the format for us. */
+	spa_format_video_raw_parse(param, &data->format.info.raw);
+	sdl_format = id_to_sdl_format(data->format.info.raw.format);
+	data->size = data->format.info.raw.size;
+
+	if (sdl_format == SDL_PIXELFORMAT_UNKNOWN) {
+		pw_stream_set_error(stream, -EINVAL, "unknown pixel format");
+		return;
+	}
+	if (data->size.width == 0 || data->size.height == 0) {
+		pw_stream_set_error(stream, -EINVAL, "invalid size");
+		return;
+	}
+
+	data->texture = SDL_CreateTexture(data->renderer,
+					  sdl_format,
+					  SDL_TEXTUREACCESS_STREAMING,
+					  data->size.width,
+					  data->size.height);
+	SDL_LockTexture(data->texture, NULL, &d, &data->stride);
+	SDL_UnlockTexture(data->texture);
+
+	/* a SPA_TYPE_OBJECT_ParamBuffers object defines the acceptable size,
+	 * number, stride etc of the buffers */
+	params[0] = spa_pod_builder_add_object(&b,
+		SPA_TYPE_OBJECT_ParamBuffers, SPA_PARAM_Buffers,
+		SPA_PARAM_BUFFERS_buffers, SPA_POD_CHOICE_RANGE_Int(8, 2, MAX_BUFFERS),
+		SPA_PARAM_BUFFERS_blocks,  SPA_POD_Int(1),
+		SPA_PARAM_BUFFERS_size,    SPA_POD_Int(data->stride * data->size.height),
+		SPA_PARAM_BUFFERS_stride,  SPA_POD_Int(data->stride),
+		SPA_PARAM_BUFFERS_dataType, SPA_POD_CHOICE_FLAGS_Int((1<<SPA_DATA_MemPtr)));
+
+	/* we are done */
+	pw_stream_update_params(stream, params, 1);
+}
+
+/* these are the stream events we listen for */
+static const struct pw_stream_events stream_events = {
+	PW_VERSION_STREAM_EVENTS,
+	.state_changed = on_stream_state_changed,
+	.param_changed = on_stream_param_changed,
+	.process = on_process,
+};
+
+static int build_format(struct data *data, struct spa_pod_builder *b, const struct spa_pod **params)
+{
+	SDL_RendererInfo info;
+
+	SDL_GetRendererInfo(data->renderer, &info);
+	params[0] = sdl_build_formats(&info, b);
+
+	fprintf(stderr, "supported SDL formats:\n");
+	spa_debug_format(2, NULL, params[0]);
+
+	return 1;
+}
+
+static int reneg_format(struct data *data)
+{
+	uint8_t buffer[1024];
+	struct spa_pod_builder b = SPA_POD_BUILDER_INIT(buffer, sizeof(buffer));
+	const struct spa_pod *params[2];
+	int32_t width, height;
+
+	if (data->format.info.raw.format == 0)
+		return -EBUSY;
+
+	width = data->counter & 1 ? 320 : 640;
+	height = data->counter & 1 ? 240 : 480;
+
+	fprintf(stderr, "renegotiate to %dx%d:\n", width, height);
+	params[0] = spa_pod_builder_add_object(&b,
+		SPA_TYPE_OBJECT_Format, SPA_PARAM_EnumFormat,
+		SPA_FORMAT_mediaType,       SPA_POD_Id(SPA_MEDIA_TYPE_video),
+		SPA_FORMAT_mediaSubtype,    SPA_POD_Id(SPA_MEDIA_SUBTYPE_raw),
+		SPA_FORMAT_VIDEO_format,    SPA_POD_Id(data->format.info.raw.format),
+		SPA_FORMAT_VIDEO_size,      SPA_POD_Rectangle(&SPA_RECTANGLE(width, height)),
+		SPA_FORMAT_VIDEO_framerate, SPA_POD_Fraction(&data->format.info.raw.framerate));
+
+	pw_stream_update_params(data->stream, params, 1);
+
+	data->counter++;
+	return 0;
+}
+
+static int reneg_buffers(struct data *data)
+{
+	uint8_t buffer[1024];
+	struct spa_pod_builder b = SPA_POD_BUILDER_INIT(buffer, sizeof(buffer));
+	const struct spa_pod *params[2];
+
+	fprintf(stderr, "renegotiate buffers\n");
+	params[0] = spa_pod_builder_add_object(&b,
+		SPA_TYPE_OBJECT_ParamBuffers, SPA_PARAM_Buffers,
+		SPA_PARAM_BUFFERS_buffers, SPA_POD_CHOICE_RANGE_Int(8, 2, MAX_BUFFERS),
+		SPA_PARAM_BUFFERS_blocks,  SPA_POD_Int(1),
+		SPA_PARAM_BUFFERS_size,    SPA_POD_Int(data->stride * data->size.height),
+		SPA_PARAM_BUFFERS_stride,  SPA_POD_Int(data->stride));
+
+	pw_stream_update_params(data->stream, params, 1);
+
+	data->counter++;
+	return 0;
+}
+
+static void on_timeout(void *userdata, uint64_t expirations)
+{
+	struct data *data = userdata;
+	if (1)
+		reneg_format(data);
+	else
+		reneg_buffers(data);
+}
+
+static void do_quit(void *userdata, int signal_number)
+{
+	struct data *data = userdata;
+	pw_main_loop_quit(data->loop);
+}
+
+int main(int argc, char *argv[])
+{
+	struct data data = { 0, };
+	const struct spa_pod *params[2];
+	uint8_t buffer[1024];
+	struct spa_pod_builder b = SPA_POD_BUILDER_INIT(buffer, sizeof(buffer));
+	struct pw_properties *props;
+	int res, n_params;
+
+	pw_init(&argc, &argv);
+
+	/* create a main loop */
+	data.loop = pw_main_loop_new(NULL);
+
+	pw_loop_add_signal(pw_main_loop_get_loop(data.loop), SIGINT, do_quit, &data);
+	pw_loop_add_signal(pw_main_loop_get_loop(data.loop), SIGTERM, do_quit, &data);
+
+	/* create a simple stream, the simple stream manages to core and remote
+	 * objects for you if you don't need to deal with them
+	 *
+	 * If you plan to autoconnect your stream, you need to provide at least
+	 * media, category and role properties
+	 *
+	 * Pass your events and a user_data pointer as the last arguments. This
+	 * will inform you about the stream state. The most important event
+	 * you need to listen to is the process event where you need to consume
+	 * the data provided to you.
+	 */
+	props = pw_properties_new(PW_KEY_MEDIA_TYPE, "Video",
+			PW_KEY_MEDIA_CATEGORY, "Capture",
+			PW_KEY_MEDIA_ROLE, "Camera",
+			NULL),
+	data.path = argc > 1 ? argv[1] : NULL;
+	if (data.path)
+		/* Set stream target if given on command line */
+		pw_properties_set(props, PW_KEY_TARGET_OBJECT, data.path);
+
+	data.stream = pw_stream_new_simple(
+			pw_main_loop_get_loop(data.loop),
+			"video-play-reneg",
+			props,
+			&stream_events,
+			&data);
+
+	if (SDL_Init(SDL_INIT_VIDEO) < 0) {
+		fprintf(stderr, "can't initialize SDL: %s\n", SDL_GetError());
+		return -1;
+	}
+
+	if (SDL_CreateWindowAndRenderer
+	    (WIDTH, HEIGHT, SDL_WINDOW_RESIZABLE, &data.window, &data.renderer)) {
+		fprintf(stderr, "can't create window: %s\n", SDL_GetError());
+		return -1;
+	}
+
+	/* build the extra parameters to connect with. To connect, we can provide
+	 * a list of supported formats.  We use a builder that writes the param
+	 * object to the stack. */
+	n_params = build_format(&data, &b, params);
+
+	/* now connect the stream, we need a direction (input/output),
+	 * an optional target node to connect to, some flags and parameters
+	 */
+	if ((res = pw_stream_connect(data.stream,
+			  PW_DIRECTION_INPUT,
+			  PW_ID_ANY,
+			  PW_STREAM_FLAG_AUTOCONNECT |	/* try to automatically connect this stream */
+			  PW_STREAM_FLAG_MAP_BUFFERS,	/* mmap the buffer data for us */
+			  params, n_params))		/* extra parameters, see above */ < 0) {
+		fprintf(stderr, "can't connect: %s\n", spa_strerror(res));
+		return -1;
+	}
+
+	data.timer = pw_loop_add_timer(pw_main_loop_get_loop(data.loop), on_timeout, &data);
+
+	/* do things until we quit the mainloop */
+	pw_main_loop_run(data.loop);
+
+	pw_stream_destroy(data.stream);
+	pw_main_loop_destroy(data.loop);
+
+	SDL_DestroyTexture(data.texture);
+	if (data.cursor)
+		SDL_DestroyTexture(data.cursor);
+	SDL_DestroyRenderer(data.renderer);
+	SDL_DestroyWindow(data.window);
+	pw_deinit();
+
+	return 0;
+}