From 4e8acf371ff4733a8d9307dda378c07513e6df36 Mon Sep 17 00:00:00 2001
From: Maxim Devaev <mdevaev@gmail.com>
Date: Thu, 11 Jan 2024 22:46:56 +0200
Subject: [PATCH] Issue #252: YVYU support

---
 man/ustreamer.1                      |  2 +-
 src/libs/frame.c                     |  1 +
 src/ustreamer/device.c               |  1 +
 src/ustreamer/device.h               |  2 +-
 src/ustreamer/encoders/cpu/encoder.c | 35 ++++++++++++++++++++++++++++
 5 files changed, 39 insertions(+), 2 deletions(-)

diff --git a/man/ustreamer.1 b/man/ustreamer.1
index 4895259..b687011 100644
--- a/man/ustreamer.1
+++ b/man/ustreamer.1
@@ -52,7 +52,7 @@ Initial image resolution. Default: 640x480.
 .TP
 .BR \-m\ \fIfmt ", " \-\-format\ \fIfmt
 Image format.
-Available: YUYV, UYVY, RGB565, RGB24, JPEG; default: YUYV.
+Available: YUYV, YVYU, UYVY, RGB565, RGB24, JPEG; default: YUYV.
 .TP
 .BR \-a\ \fIstd ", " \-\-tv\-standard\ \fIstd
 Force TV standard.
diff --git a/src/libs/frame.c b/src/libs/frame.c
index d2de28d..9a82559 100644
--- a/src/libs/frame.c
+++ b/src/libs/frame.c
@@ -73,6 +73,7 @@ unsigned us_frame_get_padding(const us_frame_s *frame) {
 	unsigned bytes_per_pixel = 0;
 	switch (frame->format) {
 		case V4L2_PIX_FMT_YUYV:
+		case V4L2_PIX_FMT_YVYU:
 		case V4L2_PIX_FMT_UYVY:
 		case V4L2_PIX_FMT_RGB565: bytes_per_pixel = 2; break;
 		case V4L2_PIX_FMT_BGR24:
diff --git a/src/ustreamer/device.c b/src/ustreamer/device.c
index 1f305a1..22f2ff9 100644
--- a/src/ustreamer/device.c
+++ b/src/ustreamer/device.c
@@ -38,6 +38,7 @@ static const struct {
 	const unsigned format; // cppcheck-suppress unusedStructMember
 } _FORMATS[] = {
 	{"YUYV",	V4L2_PIX_FMT_YUYV},
+	{"YVYU",	V4L2_PIX_FMT_YVYU},
 	{"UYVY",	V4L2_PIX_FMT_UYVY},
 	{"RGB565",	V4L2_PIX_FMT_RGB565},
 	{"RGB24",	V4L2_PIX_FMT_RGB24},
diff --git a/src/ustreamer/device.h b/src/ustreamer/device.h
index bb2d18f..7316d91 100644
--- a/src/ustreamer/device.h
+++ b/src/ustreamer/device.h
@@ -61,7 +61,7 @@
 #define US_STANDARDS_STR		"PAL, NTSC, SECAM"
 
 #define US_FORMAT_UNKNOWN		-1
-#define US_FORMATS_STR			"YUYV, UYVY, RGB565, RGB24, BGR24, MJPEG, JPEG"
+#define US_FORMATS_STR			"YUYV, YVYU, UYVY, RGB565, RGB24, BGR24, MJPEG, JPEG"
 
 #define US_IO_METHOD_UNKNOWN	-1
 #define US_IO_METHODS_STR		"MMAP, USERPTR"
diff --git a/src/ustreamer/encoders/cpu/encoder.c b/src/ustreamer/encoders/cpu/encoder.c
index d3075be..a5af917 100644
--- a/src/ustreamer/encoders/cpu/encoder.c
+++ b/src/ustreamer/encoders/cpu/encoder.c
@@ -38,6 +38,7 @@ typedef struct {
 static void _jpeg_set_dest_frame(j_compress_ptr jpeg, us_frame_s *frame);
 
 static void _jpeg_write_scanlines_yuyv(struct jpeg_compress_struct *jpeg, const us_frame_s *frame);
+static void _jpeg_write_scanlines_yvyu(struct jpeg_compress_struct *jpeg, const us_frame_s *frame);
 static void _jpeg_write_scanlines_uyvy(struct jpeg_compress_struct *jpeg, const us_frame_s *frame);
 static void _jpeg_write_scanlines_rgb565(struct jpeg_compress_struct *jpeg, const us_frame_s *frame);
 static void _jpeg_write_scanlines_rgb24(struct jpeg_compress_struct *jpeg, const us_frame_s *frame);
@@ -77,6 +78,7 @@ void us_cpu_encoder_compress(const us_frame_s *src, us_frame_s *dest, unsigned q
 	switch (src->format) {
 		// https://www.fourcc.org/yuv.php
 		WRITE_SCANLINES(V4L2_PIX_FMT_YUYV, _jpeg_write_scanlines_yuyv);
+		WRITE_SCANLINES(V4L2_PIX_FMT_YVYU, _jpeg_write_scanlines_yvyu);
 		WRITE_SCANLINES(V4L2_PIX_FMT_UYVY, _jpeg_write_scanlines_uyvy);
 		WRITE_SCANLINES(V4L2_PIX_FMT_RGB565, _jpeg_write_scanlines_rgb565);
 		WRITE_SCANLINES(V4L2_PIX_FMT_RGB24, _jpeg_write_scanlines_rgb24);
@@ -141,6 +143,39 @@ static void _jpeg_write_scanlines_yuyv(struct jpeg_compress_struct *jpeg, const
 	free(line_buf);
 }
 
+static void _jpeg_write_scanlines_yvyu(struct jpeg_compress_struct *jpeg, const us_frame_s *frame) {
+	uint8_t *line_buf;
+	US_CALLOC(line_buf, frame->width * 3);
+
+	const unsigned padding = us_frame_get_padding(frame);
+	const uint8_t *data = frame->data;
+
+	while (jpeg->next_scanline < frame->height) {
+		uint8_t *ptr = line_buf;
+
+		for (unsigned x = 0; x < frame->width; ++x) {
+			// See also: https://www.kernel.org/doc/html/v4.8/media/uapi/v4l/pixfmt-yuyv.html
+			const bool is_odd_pixel = x & 1;
+			const uint8_t y = data[is_odd_pixel ? 2 : 0];
+			const uint8_t u = data[3];
+			const uint8_t v = data[1];
+
+			ptr[0] = y;
+			ptr[1] = u;
+			ptr[2] = v;
+			ptr += 3;
+
+			data += (is_odd_pixel ? 4 : 0);
+		}
+		data += padding;
+
+		JSAMPROW scanlines[1] = {line_buf};
+		jpeg_write_scanlines(jpeg, scanlines, 1);
+	}
+
+	free(line_buf);
+}
+
 static void _jpeg_write_scanlines_uyvy(struct jpeg_compress_struct *jpeg, const us_frame_s *frame) {
 	uint8_t *line_buf;
 	US_CALLOC(line_buf, frame->width * 3);