roll my own mpjpeg encoding (with libjpeg)

7 files changed, 87 insertions, 65 deletions

diff --git a/Makefile b/Makefile
index 5ae2d4b..f9df186 100644
--- a/Makefile
+++ b/Makefile
@@ -4,10 +4,10 @@ CFLAGS += -g -std=c99 -Wall -Werror -Wextra -pedantic
 CPPFLAGS += -std=c99 -Wall -Werror -Wextra -pedantic
 CPPFLAGS += -D_GNU_SOURCE
 
-all: freenect-server freenect-server--kinect multipart-replace-http-server
+all: freenect-server multipart-replace-http-server
 .PHONY: all
 
-freenect-server--kinect: util.o -lfreenect -lusb-1.0
+freenect-server: util.o -lfreenect -lusb-1.0 -ljpeg
 multipart-replace-http-server: util.o multipart-replace.o -lpthread
 
 clean:
diff --git a/freenect-server-http.socket b/freenect-server-http.socket
new file mode 100644
index 0000000..3fc6244
--- /dev/null
+++ b/freenect-server-http.socket
@@ -0,0 +1,9 @@
+[Unit]
+Description=Kinect HTTP media streamer socket
+
+[Socket]
+ListenStream=5800
+
+[Install]
+WantedBy=sockets.target
+Also=freenect-server@accel.mjson.socket freenect-server@depth.mjpg.socket freenect-server@video.mjpg.socket
diff --git a/freenect-server--kinect.c b/freenect-server.c
index e6c9e7e..37e2a08 100644
--- a/freenect-server--kinect.c
+++ b/freenect-server.c
@@ -25,6 +25,7 @@
  */
 #include <errno.h>
 #include <error.h>
+#include <inttypes.h>
 #include <stdio.h>
 #include <stdlib.h> /* atexit */
 #include <unistd.h> /* dup2 */
@@ -32,6 +33,8 @@
 #include <libfreenect/libfreenect.h>
 #include <libusb-1.0/libusb.h>
 
+#include <jpeglib.h>
+
 #include "util.h"
 
 FILE *depth_stream = NULL;
@@ -39,29 +42,47 @@ FILE *video_stream = NULL;
 FILE *accel_stream = NULL;
 freenect_context *ctx;
 
-void dump_ffmpeg_24(FILE *stream, uint32_t timestamp UNUSED, void *data,
-                    size_t data_size)
-{
-	fwrite(data, data_size, 1, stream);
-}
+struct jpeg_error_mgr jpeg_encoder_err;
+struct jpeg_compress_struct jpeg_encoder;
+unsigned char *jpeg_encoder_buf;
+unsigned long jpeg_encoder_len;
 
-void dump_ffmpeg_pad16(FILE *stream, uint32_t timestamp UNUSED, void *data_anon,
-                       size_t data_size)
-{
-	uint16_t* data = data_anon;
-	uint16_t* end = (void*)&((char*)data_anon)[data_size];
-	while (data < end) {
-		uint16_t z = *data;
-		uint8_t out[3];
-		memset(out, (uint8_t)(z*2.0/3.0), 3);
-		fwrite(out, 3, 1, stream);
-		data = &data[1];
-	}
+void jpeg_init() {
+	jpeg_encoder.err = jpeg_std_error(&jpeg_encoder_err);
+	jpeg_create_compress(&jpeg_encoder);
+	jpeg_encoder.image_width = 640;
+	jpeg_encoder.image_height = 480;
+	jpeg_encoder.input_components = 3;
+	jpeg_encoder.in_color_space = JCS_RGB;
+	jpeg_set_defaults(&jpeg_encoder);
+	jpeg_mem_dest(&jpeg_encoder, &jpeg_encoder_buf, &jpeg_encoder_len);
 }
 
+void write_imageframe(FILE *stream, JSAMPLE *data) {
+	JSAMPLE *row_pointers[480];
+	for (size_t i = 0; i < 480; i++)
+		row_pointers[i] = &data[i*640*3];
+
+	jpeg_start_compress(&jpeg_encoder, TRUE);
+	while (jpeg_encoder.next_scanline < jpeg_encoder.image_height)
+		jpeg_write_scanlines(&jpeg_encoder, &row_pointers[jpeg_encoder.next_scanline], 480-jpeg_encoder.next_scanline);
+	jpeg_finish_compress(&jpeg_encoder);
+
+	if (fprintf(stream,
+	            "--ffserver\r\n"
+	            "Content-type: image/jpeg\r\n"
+	            "Content-length: %lu\r\n"
+	            "\r\n",
+	            jpeg_encoder_len) < 1)
+		error(EXIT_FAILURE, ferror(stream), "writing header");
+	if (fwrite(jpeg_encoder_buf, jpeg_encoder_len, 1, stream) < 1)
+		error(EXIT_FAILURE, ferror(stream), "writing body");
+	if (fwrite("\r\n", 2, 1, stream) < 1)
+		error(EXIT_FAILURE, ferror(stream), "writing footer");
+	fflush(stream);
+}
 
-void handle_accel(freenect_device *dev UNUSED, freenect_raw_tilt_state* data)
-{
+void handle_accel(freenect_device *dev UNUSED, freenect_raw_tilt_state* data) {
 	double x, y, z, angle;
 	freenect_get_mks_accel(data, &x, &y, &z);
 	angle = freenect_get_tilt_degs(data);
@@ -70,10 +91,13 @@ void handle_accel(freenect_device *dev UNUSED, freenect_raw_tilt_state* data)
 	switch (data->tilt_status) {
 	case TILT_STATUS_STOPPED:
 		motor = "stopped";
+		break;
 	case TILT_STATUS_LIMIT:
 		motor = "limit";
+		break;
 	case TILT_STATUS_MOVING:
 		motor = "moving";
+		break;
 	default:
 		motor = "unknown";
 	}
@@ -95,19 +119,28 @@ void handle_accel(freenect_device *dev UNUSED, freenect_raw_tilt_state* data)
 	        "\r\n"
 	        "%s\r\n",
 	        len, json);
+	fflush(accel_stream);
 }
 
-void handle_depth(freenect_device *dev UNUSED, void *depth, uint32_t timestamp)
-{
-	dump_ffmpeg_pad16(depth_stream, timestamp, depth,
-	                  freenect_find_depth_mode(FREENECT_RESOLUTION_MEDIUM,
-	                                           FREENECT_DEPTH_11BIT).bytes);
+uint8_t depth_rgb[640*480*3];
+void handle_depth(freenect_device *dev, void *depth, uint32_t timestamp UNUSED) {
+	uint32_t size = freenect_get_current_depth_mode(dev).bytes;
+	if (size != 460*480*2)
+		error(EXIT_FAILURE, 0, "handle_depth: expected 640*480*2 byte frame, but got %"PRId32, size);
+	/* scale the 11-bit values into 8-bit values */
+	uint16_t *depth_grey = depth;
+	for (size_t i = 0; i < 640*480; i++)
+		depth_rgb[i*3+0] = depth_rgb[i*3+1] = depth_rgb[i*3+2] = (uint8_t)(depth_grey[i]*8.0/11.0);
+	/* write the image */
+	write_imageframe(depth_stream, depth_rgb);
 }
 
-void handle_video(freenect_device *dev, void *rgb, uint32_t timestamp)
-{
-	dump_ffmpeg_24(video_stream, timestamp, rgb,
-	               freenect_get_current_video_mode(dev).bytes);
+void handle_video(freenect_device *dev, void *rgb, uint32_t timestamp UNUSED) {
+	uint32_t size = freenect_get_current_video_mode(dev).bytes;
+	if (size != 460*480*3)
+		error(EXIT_FAILURE, 0, "handle_video: expected 640*480*3 byte frame, but got %"PRId32, size);
+	/* write the image */
+	write_imageframe(video_stream, rgb);
 }
 
 void print_mode(const char *name, freenect_frame_mode mode) {
diff --git a/freenect-server.service b/freenect-server.service
index 5a2d4e2..fbc2035 100644
--- a/freenect-server.service
+++ b/freenect-server.service
@@ -1,7 +1,7 @@
 [Unit]
-Description=Kinect media streamer
+Description=Kinect media streamer backend
 After=network.target
-Requires=freenect-server.socket
+Requires=freenect-server@accel.socket freenect-server@depth.socket freenect-server@video.socket
 
 [Service]
 Type=simple
diff --git a/freenect-server.sh b/freenect-server.sh
deleted file mode 100644
index e88acbe..0000000
--- a/freenect-server.sh
+++ /dev/null
@@ -1,25 +0,0 @@
-#!/usr/bin/env bash
-# Copyright 2016 Luke Shumaker
-
-PATH="$PATH:$(dirname -- "$0")"
-
-t="$(mktemp -d --tmpdir "${0##*/}.XXXXXXXXXX")"
-
-mkfifo $t/video.rgb24
-mkfifo $t/depth.rgb24
-mkfifo $t/video.mjpg
-mkfifo $t/depth.mjpg
-mkfifo $t/accel.mjson
-
-( freenect-server--kinect -v $t/video.rgb24 -d $t/depth.rgb24 -a $t/accel.mjson; echo "EXITED: freenect-server--kinect: $?") & pids+=($!)
-( multipart-replace-http-server "$1" "$2" $t/video.mjpg $t/depth.mjpg $t/accel.mjson; echo "EXITED: freenect-server--http: $?") & pids+=($!)
-( ffmpeg -loglevel warning -pixel_format rgb24 -s 640x480 -f rawvideo -i $t/video.rgb24 -q:v 1 -f mpjpeg - > $t/video.mjpg; echo "EXITED: ffmpeg video: $?") & pids+=($!)
-( ffmpeg -loglevel warning -pixel_format rgb24 -s 640x480 -f rawvideo -i $t/depth.rgb24 -q:v 1 -f mpjpeg - > $t/depth.mjpg; echo "EXITED: ffmpeg depth: $?") & pids+=($!)
-
-cleanup() {
-	kill -- "${pids[@]}" 2>/dev/null
-	rm -rf -- "$t"
-}
-trap cleanup EXIT
-
-wait
diff --git a/freenect-server.socket b/freenect-server.socket
deleted file mode 100644
index 4b98eca..0000000
--- a/freenect-server.socket
+++ /dev/null
@@ -1,8 +0,0 @@
-[Unit]
-Description=Kinect media streamer socket
-
-[Socket]
-ListenStream=5800
-
-[Install]
-WantedBy=sockets.target
diff --git a/freenect-server@.socket b/freenect-server@.socket
new file mode 100644
index 0000000..841f2fd
--- /dev/null
+++ b/freenect-server@.socket
@@ -0,0 +1,13 @@
+[Unit]
+Description=Kinect media streamer internal %I stream
+After=network.target
+
+[Socket]
+SocketUser=alarm
+SocketGroup=alarm
+ListenFIFO=/run/freenect-server/Ii.fifo
+FileDescriptorName=%I
+Service=freenect-server.service
+
+[Install]
+WantedBy=sockets.target