Add a demo client for dmabuf export

3 files changed, 778 insertions, 0 deletions

diff --git a/examples/dmabuf-capture.c b/examples/dmabuf-capture.c
new file mode 100644
index 00000000..f249d437
--- /dev/null
+++ b/examples/dmabuf-capture.c
@@ -0,0 +1,767 @@
+#define _XOPEN_SOURCE 700
+#define _POSIX_C_SOURCE 199309L
+#include <poll.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <signal.h>
+
+#include "wlr-export-dmabuf-unstable-v1-client-protocol.h"
+
+#include <libavformat/avformat.h>
+#include <libavutil/pixdesc.h>
+#include <libavutil/display.h>
+#include <libavutil/hwcontext_drm.h>
+
+struct wayland_output {
+	struct wl_list link;
+	uint32_t id;
+	struct wl_output *output;
+	char *make;
+	char *model;
+	int width;
+	int height;
+	AVRational framerate;
+};
+
+struct capture_context {
+	AVClass *class; /* For pretty logging */
+	struct wl_display *display;
+	struct wl_registry *registry;
+	struct zwlr_export_dmabuf_manager_v1 *export_manager;
+
+	struct wl_list output_list;
+
+	/* Target */
+	struct wl_output *target_output;
+	uint32_t target_client;
+
+	/* Main frame callback */
+	struct zwlr_export_dmabuf_frame_v1 *frame_callback;
+
+	/* If something happens during capture */
+	int err;
+	int quit;
+
+	/* FFmpeg specific parts */
+	AVFrame *current_frame;
+	AVBufferRef *drm_device_ref;
+	AVBufferRef *drm_frames_ref;
+
+    AVBufferRef *mapped_device_ref;
+    AVBufferRef *mapped_frames_ref;
+
+    AVFormatContext *avf;
+    AVCodecContext *avctx;
+
+    int64_t start_pts;
+
+	/* Config */
+	enum AVPixelFormat software_format;
+	enum AVHWDeviceType hw_device_type;
+	AVDictionary *encoder_opts;
+	int is_software_encoder;
+	char *hardware_device;
+	char *out_filename;
+	char *encoder_name;
+	float out_bitrate;
+};
+
+static void output_handle_geometry(void *data, struct wl_output *wl_output,
+		int32_t x, int32_t y, int32_t phys_width, int32_t phys_height,
+		int32_t subpixel, const char *make, const char *model,
+		int32_t transform) {
+	struct wayland_output *output = data;
+	output->make  = av_strdup(make);
+	output->model = av_strdup(model);
+}
+
+static void output_handle_mode(void *data, struct wl_output *wl_output,
+		uint32_t flags, int32_t width, int32_t height, int32_t refresh) {
+	if (flags & WL_OUTPUT_MODE_CURRENT) {
+	    struct wayland_output *output = data;
+	    output->width     = width;
+	    output->height    = height;
+	    output->framerate = (AVRational){ refresh, 1000 };
+	}
+}
+
+static void output_handle_done(void* data, struct wl_output *wl_output) {
+	/* Nothing to do */
+}
+
+static void output_handle_scale(void* data, struct wl_output *wl_output,
+		int32_t factor) {
+	/* Nothing to do */
+}
+
+static const struct wl_output_listener output_listener = {
+	output_handle_geometry,
+	output_handle_mode,
+	output_handle_done,
+	output_handle_scale,
+};
+
+static void registry_handle_add(void *data, struct wl_registry *reg,
+		uint32_t id, const char *interface, uint32_t ver) {
+	struct capture_context *ctx = data;
+
+	if (!strcmp(interface, wl_output_interface.name)) {
+		struct wayland_output *output = av_mallocz(sizeof(*output));
+
+		output->id     = id;
+		output->output = wl_registry_bind(reg, id, &wl_output_interface, 1);
+
+		wl_output_add_listener(output->output, &output_listener, output);
+		wl_list_insert(&ctx->output_list, &output->link);
+	}
+
+	if (!strcmp(interface, zwlr_export_dmabuf_manager_v1_interface.name)) {
+			ctx->export_manager = wl_registry_bind(reg, id,
+					&zwlr_export_dmabuf_manager_v1_interface, 1);
+	}
+}
+
+static void remove_output(struct wayland_output *out) {
+	wl_list_remove(&out->link);
+	av_free(out->make);
+	av_free(out->model);
+	av_free(out);
+	return;
+}
+
+static struct wayland_output *find_output(struct capture_context *ctx,
+		struct wl_output *out, uint32_t id) {
+	struct wayland_output *output, *tmp;
+	wl_list_for_each_safe(output, tmp, &ctx->output_list, link)
+		if ((output->output == out) || (output->id == id))
+			return output;
+    return NULL;
+}
+
+static void registry_handle_remove(void *data, struct wl_registry *reg,
+		uint32_t id) {
+	remove_output(find_output((struct capture_context *)data, NULL, id));
+}
+
+static const struct wl_registry_listener registry_listener = {
+	registry_handle_add,
+	registry_handle_remove,
+};
+
+static void frame_free(void *opaque, uint8_t *data) {
+	AVDRMFrameDescriptor *desc = (AVDRMFrameDescriptor *)data;
+
+	for (int i = 0; i < desc->nb_objects; ++i) {
+		close(desc->objects[i].fd);
+	}
+
+	zwlr_export_dmabuf_frame_v1_destroy(opaque);
+
+	av_free(data);
+}
+
+static void frame_start(void *data, struct zwlr_export_dmabuf_frame_v1 *frame,
+		uint32_t width, uint32_t height, uint32_t offset_x, uint32_t offset_y,
+		uint32_t buffer_flags, uint32_t flags, uint32_t format,
+		uint32_t mod_high, uint32_t mod_low, uint32_t num_objects,
+		uint32_t num_planes) {
+	struct capture_context *ctx = data;
+	int err = 0;
+
+	/* Allocate DRM specific struct */
+	AVDRMFrameDescriptor *desc = av_mallocz(sizeof(*desc));
+	if (!desc) {
+		err = AVERROR(ENOMEM);
+		goto fail;
+	}
+
+	desc->nb_objects = num_objects;
+	desc->objects[0].format_modifier = ((uint64_t)mod_high << 32) | mod_low;
+
+	desc->nb_layers = 1;
+	desc->layers[0].format = format;
+	desc->layers[0].nb_planes = num_planes;
+
+	/* Allocate a frame */
+	AVFrame *f = av_frame_alloc();
+	if (!f) {
+		err = AVERROR(ENOMEM);
+		goto fail;
+	}
+
+	/* Set base frame properties */
+	ctx->current_frame = f;
+	f->width  = width;
+	f->height = height;
+	f->format = AV_PIX_FMT_DRM_PRIME;
+
+	/* Set the frame data to the DRM specific struct */
+	f->buf[0] = av_buffer_create((uint8_t*)desc, sizeof(*desc),
+			&frame_free, frame, 0);
+	if (!f->buf[0]) {
+		err = AVERROR(ENOMEM);
+		goto fail;
+	}
+
+	f->data[0] = (uint8_t*)desc;
+
+	return;
+
+fail:
+	ctx->err = err;
+	frame_free(frame, (uint8_t *)desc);
+}
+
+static void frame_object(void *data, struct zwlr_export_dmabuf_frame_v1 *frame,
+		uint32_t index, int32_t fd, uint32_t size) {
+	struct capture_context *ctx = data;
+	AVFrame *f = ctx->current_frame;
+	AVDRMFrameDescriptor *desc = (AVDRMFrameDescriptor *)f->data[0];
+
+	desc->objects[index].fd   = fd;
+	desc->objects[index].size = size;
+}
+
+static void frame_plane(void *data, struct zwlr_export_dmabuf_frame_v1 *frame,
+		uint32_t index, uint32_t object_index,
+		uint32_t offset, uint32_t stride) {
+	struct capture_context *ctx = data;
+	AVFrame *f = ctx->current_frame;
+	AVDRMFrameDescriptor *desc = (AVDRMFrameDescriptor *)f->data[0];
+
+	desc->layers[0].planes[index].object_index = object_index;
+	desc->layers[0].planes[index].offset       = offset;
+	desc->layers[0].planes[index].pitch        = stride;
+}
+
+static const uint32_t pixfmt_to_drm_map[] = {
+	[AV_PIX_FMT_NV12] = WL_SHM_FORMAT_NV12,
+	[AV_PIX_FMT_BGRA] = WL_SHM_FORMAT_ARGB8888,
+	[AV_PIX_FMT_BGR0] = WL_SHM_FORMAT_XRGB8888,
+	[AV_PIX_FMT_RGBA] = WL_SHM_FORMAT_ABGR8888,
+	[AV_PIX_FMT_RGB0] = WL_SHM_FORMAT_XBGR8888,
+	[AV_PIX_FMT_ABGR] = WL_SHM_FORMAT_RGBA8888,
+	[AV_PIX_FMT_0BGR] = WL_SHM_FORMAT_RGBX8888,
+	[AV_PIX_FMT_ARGB] = WL_SHM_FORMAT_BGRA8888,
+	[AV_PIX_FMT_0RGB] = WL_SHM_FORMAT_BGRX8888,
+};
+
+static enum AVPixelFormat drm_fmt_to_pixfmt(uint32_t fmt) {
+	for (enum AVPixelFormat i = 0; i < AV_PIX_FMT_NB; i++) {
+		if (pixfmt_to_drm_map[i] == fmt) {
+			return i;
+		}
+	}
+	return AV_PIX_FMT_NONE;
+}
+
+static int attach_drm_frames_ref(struct capture_context *ctx, AVFrame *f,
+		enum AVPixelFormat sw_format) {
+	int err = 0;
+	AVHWFramesContext *hwfc;
+
+	if (ctx->drm_frames_ref) {
+		hwfc = (AVHWFramesContext*)ctx->drm_frames_ref->data;
+		if (hwfc->width == f->width && hwfc->height == f->height &&
+				hwfc->sw_format == sw_format) {
+			goto attach;
+		}
+		av_buffer_unref(&ctx->drm_frames_ref);
+	}
+
+	ctx->drm_frames_ref = av_hwframe_ctx_alloc(ctx->drm_device_ref);
+	if (!ctx->drm_frames_ref) {
+		err = AVERROR(ENOMEM);
+		goto fail;
+	}
+
+	hwfc = (AVHWFramesContext*)ctx->drm_frames_ref->data;
+
+	hwfc->format    = f->format;
+	hwfc->sw_format = sw_format;
+	hwfc->width     = f->width;
+	hwfc->height    = f->height;
+
+	err = av_hwframe_ctx_init(ctx->drm_frames_ref);
+	if (err) {
+		av_log(ctx, AV_LOG_ERROR, "AVHWFramesContext init failed: %s!\n",
+				av_err2str(err));
+		goto fail;
+	}
+
+attach:
+	/* Set frame hardware context referencce */
+	f->hw_frames_ctx = av_buffer_ref(ctx->drm_frames_ref);
+	if (!f->hw_frames_ctx) {
+		err = AVERROR(ENOMEM);
+		goto fail;
+	}
+
+	return 0;
+
+fail:
+	av_buffer_unref(&ctx->drm_frames_ref);
+	return err;
+}
+
+static void register_cb(struct capture_context *ctx);
+
+static void frame_ready(void *data, struct zwlr_export_dmabuf_frame_v1 *frame,
+		uint32_t tv_sec_hi, uint32_t tv_sec_lo, uint32_t tv_nsec) {
+	struct capture_context *ctx = data;
+	AVFrame *f = ctx->current_frame;
+	AVDRMFrameDescriptor *desc = (AVDRMFrameDescriptor *)f->data[0];
+	int err = 0;
+
+	/* Attach the hardware frame context to the frame */
+	err = attach_drm_frames_ref(ctx, f, drm_fmt_to_pixfmt(desc->layers[0].format));
+	if (err) {
+		goto end;
+	}
+
+	AVFrame *mapped_frame = av_frame_alloc();
+	if (!mapped_frame) {
+		err = AVERROR(ENOMEM);
+		goto end;
+	}
+
+	AVHWFramesContext *mapped_hwfc;
+	mapped_hwfc = (AVHWFramesContext *)ctx->mapped_frames_ref->data;
+    mapped_frame->format = mapped_hwfc->format;
+
+	/* Set frame hardware context referencce */
+	mapped_frame->hw_frames_ctx = av_buffer_ref(ctx->mapped_frames_ref);
+	if (!mapped_frame->hw_frames_ctx) {
+		err = AVERROR(ENOMEM);
+		goto end;
+	}
+
+	err = av_hwframe_map(mapped_frame, f, 0);
+	if (err) {
+	    av_log(ctx, AV_LOG_ERROR, "Error mapping: %s!\n", av_err2str(err));
+	    goto end;
+	}
+
+	AVFrame *enc_input = mapped_frame;
+
+	if (ctx->is_software_encoder) {
+		AVFrame *soft_frame = av_frame_alloc();
+		av_hwframe_transfer_data(soft_frame, mapped_frame, 0);
+		av_frame_free(&mapped_frame);
+		enc_input = soft_frame;
+	}
+
+	/* Nanoseconds */
+	enc_input->pts = (((uint64_t)tv_sec_hi) << 32) | tv_sec_lo;
+	enc_input->pts *= 1000000000;
+	enc_input->pts += tv_nsec;
+
+	if (!ctx->start_pts) {
+		ctx->start_pts = enc_input->pts;
+	}
+
+	enc_input->pts -= ctx->start_pts;
+
+	enc_input->pts = av_rescale_q(enc_input->pts, (AVRational){ 1, 1000000000 },
+			ctx->avctx->time_base);
+
+	do {
+		err = avcodec_send_frame(ctx->avctx, enc_input);
+
+        av_frame_free(&enc_input);
+
+		if (err) {
+			av_log(ctx, AV_LOG_ERROR, "Error encoding: %s!\n", av_err2str(err));
+			goto end;
+		}
+
+		while (1) {
+			AVPacket pkt;
+			av_init_packet(&pkt);
+
+			int ret = avcodec_receive_packet(ctx->avctx, &pkt);
+			if (ret == AVERROR(EAGAIN)) {
+				break;
+			} else if (ret == AVERROR_EOF) {
+				av_log(ctx, AV_LOG_INFO, "Encoder flushed!\n");
+				ctx->quit = 2;
+				goto end;
+			} else if (ret) {
+				av_log(ctx, AV_LOG_ERROR, "Error encoding: %s!\n",
+						av_err2str(ret));
+				err = ret;
+				goto end;
+			}
+
+			pkt.stream_index = 0;
+			err = av_interleaved_write_frame(ctx->avf, &pkt);
+
+			av_packet_unref(&pkt);
+
+			if (err) {
+				av_log(ctx, AV_LOG_ERROR, "Writing packet fail: %s!\n",
+						av_err2str(err));
+				goto end;
+			}
+		};
+	} while (ctx->quit);
+
+	av_log(NULL, AV_LOG_INFO, "Encoded frame %i!\n", ctx->avctx->frame_number);
+
+	register_cb(ctx);
+
+end:
+	ctx->err = err;
+	av_frame_free(&ctx->current_frame);
+}
+
+static void frame_cancel(void *data, struct zwlr_export_dmabuf_frame_v1 *frame,
+		uint32_t reason) {
+	struct capture_context *ctx = data;
+	av_log(ctx, AV_LOG_WARNING, "Frame cancelled!\n");
+	av_frame_free(&ctx->current_frame);
+	if (reason != ZWLR_EXPORT_DMABUF_FRAME_V1_CANCEL_REASON_PERNAMENT)
+		register_cb(ctx);
+}
+
+static const struct zwlr_export_dmabuf_frame_v1_listener frame_listener = {
+	frame_start,
+	frame_object,
+	frame_plane,
+	frame_ready,
+	frame_cancel,
+};
+
+static void register_cb(struct capture_context *ctx)
+{
+	ctx->frame_callback =
+		zwlr_export_dmabuf_manager_v1_capture_output(ctx->export_manager, 0,
+				ctx->target_output);
+
+	zwlr_export_dmabuf_frame_v1_add_listener(ctx->frame_callback,
+			&frame_listener, ctx);
+}
+
+static int init_lavu_hwcontext(struct capture_context *ctx) {
+
+	/* DRM hwcontext */
+	ctx->drm_device_ref = av_hwdevice_ctx_alloc(AV_HWDEVICE_TYPE_DRM);
+	if (!ctx->drm_device_ref)
+		return AVERROR(ENOMEM);
+
+	AVHWDeviceContext *ref_data = (AVHWDeviceContext*)ctx->drm_device_ref->data;
+	AVDRMDeviceContext *hwctx = ref_data->hwctx;
+
+	/* We don't need a device (we don't even know it and can't open it) */
+	hwctx->fd = -1;
+
+	av_hwdevice_ctx_init(ctx->drm_device_ref);
+
+	/* Mapped hwcontext */
+	int err = av_hwdevice_ctx_create(&ctx->mapped_device_ref,
+			ctx->hw_device_type, ctx->hardware_device, NULL, 0);
+	if (err < 0) {
+		av_log(ctx, AV_LOG_ERROR, "Failed to create a hardware device: %s\n",
+				av_err2str(err));
+		return err;
+	}
+
+	return 0;
+}
+
+static int set_hwframe_ctx(struct capture_context *ctx,
+		AVBufferRef *hw_device_ctx)
+{
+    AVHWFramesContext *frames_ctx = NULL;
+    int err = 0;
+
+    if (!(ctx->mapped_frames_ref = av_hwframe_ctx_alloc(hw_device_ctx))) {
+        return AVERROR(ENOMEM);
+    }
+
+	AVHWFramesConstraints *cst =
+			av_hwdevice_get_hwframe_constraints(ctx->mapped_device_ref, NULL);
+	if (!cst) {
+		av_log(ctx, AV_LOG_ERROR, "Failed to get hw device constraints!\n");
+		av_buffer_unref(&ctx->mapped_frames_ref);
+		return AVERROR(ENOMEM);
+	}
+
+	frames_ctx = (AVHWFramesContext *)(ctx->mapped_frames_ref->data);
+	frames_ctx->format    = cst->valid_hw_formats[0];
+	frames_ctx->sw_format = ctx->avctx->pix_fmt;
+	frames_ctx->width     = ctx->avctx->width;
+	frames_ctx->height    = ctx->avctx->height;
+	frames_ctx->initial_pool_size = 16;
+
+	av_hwframe_constraints_free(&cst);
+
+	if ((err = av_hwframe_ctx_init(ctx->mapped_frames_ref)) < 0) {
+		av_log(ctx, AV_LOG_ERROR, "Failed to initialize hw frame context: %s!\n",
+				av_err2str(err));
+		av_buffer_unref(&ctx->mapped_frames_ref);
+		return err;
+	}
+
+	if (!ctx->is_software_encoder) {
+		ctx->avctx->pix_fmt = frames_ctx->format;
+		ctx->avctx->hw_frames_ctx = av_buffer_ref(ctx->mapped_frames_ref);
+		if (!ctx->avctx->hw_frames_ctx) {
+			av_buffer_unref(&ctx->mapped_frames_ref);
+			err = AVERROR(ENOMEM);
+		}
+	}
+
+    return err;
+}
+
+static int init_encoding(struct capture_context *ctx) {
+	int err;
+
+	/* lavf init */
+	err = avformat_alloc_output_context2(&ctx->avf, NULL,
+			NULL, ctx->out_filename);
+    if (err) {
+        av_log(ctx, AV_LOG_ERROR, "Unable to init lavf context!\n");
+        return err;
+    }
+
+    AVStream *st = avformat_new_stream(ctx->avf, NULL);
+    if (!st) {
+        av_log(ctx, AV_LOG_ERROR, "Unable to alloc stream!\n");
+        return 1;
+    }
+
+	/* Find encoder */
+    AVCodec *out_codec = avcodec_find_encoder_by_name(ctx->encoder_name);
+    if (!out_codec) {
+        av_log(ctx, AV_LOG_ERROR, "Codec not found (not compiled in lavc?)!\n");
+        return AVERROR(EINVAL);
+    }
+    ctx->avf->oformat->video_codec = out_codec->id;
+    ctx->is_software_encoder = !(out_codec->capabilities & AV_CODEC_CAP_HARDWARE);
+
+	ctx->avctx = avcodec_alloc_context3(out_codec);
+    if (!ctx->avctx)
+        return 1;
+
+    ctx->avctx->opaque            = ctx;
+    ctx->avctx->bit_rate          = (int)ctx->out_bitrate*1000000.0f;
+    ctx->avctx->pix_fmt           = ctx->software_format;
+    ctx->avctx->time_base         = (AVRational){ 1, 1000 };
+    ctx->avctx->compression_level = 7;
+    ctx->avctx->width             = find_output(ctx, ctx->target_output, 0)->width;
+    ctx->avctx->height            = find_output(ctx, ctx->target_output, 0)->height;
+
+	if (ctx->avf->oformat->flags & AVFMT_GLOBALHEADER)
+		ctx->avctx->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;
+
+	st->id             = 0;
+    st->time_base      = ctx->avctx->time_base;
+    st->avg_frame_rate = find_output(ctx, ctx->target_output, 0)->framerate;
+
+    /* Init hw frames context */
+    err = set_hwframe_ctx(ctx, ctx->mapped_device_ref);
+    if (err)
+	    return err;
+
+	err = avcodec_open2(ctx->avctx, out_codec, &ctx->encoder_opts);
+	if (err) {
+        av_log(ctx, AV_LOG_ERROR, "Cannot open encoder: %s!\n",
+        		av_err2str(err));
+        return err;
+    }
+
+	if (avcodec_parameters_from_context(st->codecpar, ctx->avctx) < 0) {
+        av_log(ctx, AV_LOG_ERROR, "Couldn't copy codec params: %s!\n",
+        		av_err2str(err));
+        return err;
+    }
+
+    /* Debug print */
+    av_dump_format(ctx->avf, 0, ctx->out_filename, 1);
+
+    /* Open for writing */
+    err = avio_open(&ctx->avf->pb, ctx->out_filename, AVIO_FLAG_WRITE);
+    if (err) {
+        av_log(ctx, AV_LOG_ERROR, "Couldn't open %s: %s!\n", ctx->out_filename,
+        		av_err2str(err));
+        return err;
+    }
+
+	err = avformat_write_header(ctx->avf, NULL);
+    if (err) {
+        av_log(ctx, AV_LOG_ERROR, "Couldn't write header: %s!\n", av_err2str(err));
+        return err;
+    }
+
+	return err;
+}
+
+struct capture_context *q_ctx = NULL;
+
+void on_quit_signal(int signo) {
+	printf("\r");
+	q_ctx->quit = 1;
+}
+
+static int main_loop(struct capture_context *ctx) {
+	int err;
+
+    q_ctx = ctx;
+
+    if (signal(SIGINT, on_quit_signal) == SIG_ERR) {
+		av_log(ctx, AV_LOG_ERROR, "Unable to install signal handler!\n");
+        return AVERROR(EINVAL);
+    }
+
+	err = init_lavu_hwcontext(ctx);
+	if (err)
+		return err;
+
+	err = init_encoding(ctx);
+	if (err)
+		return err;
+
+	/* Start the frame callback */
+	register_cb(ctx);
+
+	while (!ctx->err && ctx->quit < 2) {
+	    while (wl_display_prepare_read(ctx->display) != 0) {
+			wl_display_dispatch_pending(ctx->display);
+		}
+
+        wl_display_flush(ctx->display);
+
+		struct pollfd fds[1] = {
+			{ .fd = wl_display_get_fd(ctx->display), .events = POLLIN },
+		};
+
+		poll(fds, 1, -1);
+
+		if (!(fds[0].revents & POLLIN)) {
+			wl_display_cancel_read(ctx->display);
+		}
+
+		if (fds[0].revents & (POLLERR | POLLHUP | POLLNVAL)) {
+			av_log(ctx, AV_LOG_ERROR, "Error occurred on the display fd!\n");
+			break;
+		}
+
+		if (fds[0].revents & POLLIN) {
+		    if (wl_display_read_events(ctx->display) < 0) {
+				av_log(ctx, AV_LOG_ERROR, "Failed to read Wayland events!\n");
+				break;
+			}
+			wl_display_dispatch_pending(ctx->display);
+		}
+	}
+
+	err = av_write_trailer(ctx->avf);
+    if (err) {
+        av_log(ctx, AV_LOG_ERROR, "Error writing trailer: %s!\n",
+        		av_err2str(err));
+        return err;
+    }
+
+    av_log(ctx, AV_LOG_INFO, "Wrote trailer!\n");
+
+	return ctx->err;
+}
+
+static int init(struct capture_context *ctx) {
+	ctx->display = wl_display_connect(NULL);
+	if (!ctx->display) {
+		av_log(ctx, AV_LOG_ERROR, "Failed to connect to display!\n");
+		return AVERROR(EINVAL);
+	}
+
+	wl_list_init(&ctx->output_list);
+
+	ctx->registry = wl_display_get_registry(ctx->display);
+    wl_registry_add_listener(ctx->registry, &registry_listener, ctx);
+
+	wl_display_roundtrip(ctx->display);
+	wl_display_dispatch(ctx->display);
+
+	if (!ctx->export_manager) {
+		av_log(ctx, AV_LOG_ERROR, "Compositor doesn't support %s!\n",
+				zwlr_export_dmabuf_manager_v1_interface.name);
+		return -1;
+	}
+
+	return 0;
+}
+
+static void print_capturable_surfaces(struct capture_context *ctx) {
+
+	struct wayland_output *o, *tmp_o;
+	wl_list_for_each_reverse_safe(o, tmp_o, &ctx->output_list, link) {
+		ctx->target_output = o->output; /* Default is first, whatever */
+		av_log(ctx, AV_LOG_INFO, "Capturable output: %s Model: %s:\n",
+				o->make, o->model);
+	}
+
+	av_log(ctx, AV_LOG_INFO, "Capturing from output: %s!\n",
+			find_output(ctx, ctx->target_output, 0)->model);
+}
+
+static void uninit(struct capture_context *ctx);
+
+int main(int argc, char *argv[]) {
+	int err;
+	struct capture_context ctx = { 0 };
+	ctx.class = &((AVClass) {
+		.class_name = "dmabuf-capture",
+		.item_name  = av_default_item_name,
+		.version    = LIBAVUTIL_VERSION_INT,
+	});
+
+	err = init(&ctx);
+	if (err)
+		goto end;
+
+	print_capturable_surfaces(&ctx);
+
+	ctx.hw_device_type = av_hwdevice_find_type_by_name("vaapi");
+	ctx.hardware_device = "/dev/dri/renderD128";
+
+	ctx.encoder_name = "libx264";
+	ctx.software_format = av_get_pix_fmt("nv12");
+	av_dict_set(&ctx.encoder_opts, "preset", "veryfast", 0);
+
+	ctx.out_filename = "dmabuf_recording_01.mkv";
+	ctx.out_bitrate = 29.2f; /* Mbps */
+
+	err = main_loop(&ctx);
+	if (err)
+		goto end;
+
+end:
+	uninit(&ctx);
+	return err;
+}
+
+static void uninit(struct capture_context *ctx) {
+	struct wayland_output *output, *tmp_o;
+	wl_list_for_each_safe(output, tmp_o, &ctx->output_list, link)
+		remove_output(output);
+
+	if (ctx->export_manager)
+		zwlr_export_dmabuf_manager_v1_destroy(ctx->export_manager);
+
+	av_buffer_unref(&ctx->drm_frames_ref);
+    av_buffer_unref(&ctx->drm_device_ref);
+    av_buffer_unref(&ctx->mapped_frames_ref);
+    av_buffer_unref(&ctx->mapped_device_ref);
+
+	av_dict_free(&ctx->encoder_opts);
+
+	avcodec_close(ctx->avctx);
+	if (ctx->avf) {
+		avio_closep(&ctx->avf->pb);
+	}
+	avformat_free_context(ctx->avf);
+}
diff --git a/examples/meson.build b/examples/meson.build
index 4725b989..6a0bc46c 100644
--- a/examples/meson.build
+++ b/examples/meson.build
@@ -1,6 +1,10 @@
 threads = dependency('threads')
 wayland_cursor = dependency('wayland-cursor')
 
+libavutil = dependency('libavutil')
+libavcodec = dependency('libavcodec')
+libavformat = dependency('libavformat')
+
 executable('simple', 'simple.c', dependencies: wlroots)
 executable('pointer', 'pointer.c', dependencies: wlroots)
 executable('touch', 'touch.c', 'cat.c', dependencies: wlroots)
@@ -38,3 +42,9 @@ executable(
 	'input-inhibitor.c',
 	dependencies: [wayland_cursor, wayland_client, wlr_protos, wlroots]
 )
+
+executable(
+	'dmabuf-capture',
+	'dmabuf-capture.c',
+	dependencies: [wayland_client, wlr_protos, libavutil, libavcodec, libavformat]
+)
diff --git a/protocol/meson.build b/protocol/meson.build
index a14e9723..ca0d82b5 100644
--- a/protocol/meson.build
+++ b/protocol/meson.build
@@ -50,6 +50,7 @@ client_protocols = [
 	[wl_protocol_dir, 'unstable/idle-inhibit/idle-inhibit-unstable-v1.xml'],
 	'idle.xml',
 	'screenshooter.xml',
+	'wlr-export-dmabuf-unstable-v1.xml',
 	'wlr-layer-shell-unstable-v1.xml',
 	'wlr-input-inhibitor-unstable-v1.xml',
 ]