Add control for video subsampling
Add '-s' to assign jpeg subsampling.
0: 444, 1: 420
Using 420 will make video lack of detail compared to 444, but cut
amount of video data by half. This could be useful for some cases.
Change-Id: I48836a7117f7e3b9986e3f5c6a92974c9268525e
Signed-off-by: Jammy Huang <jammy_huang@aspeedtech.com>
diff --git a/ikvm_args.cpp b/ikvm_args.cpp
index 21373aa..19642af 100644
--- a/ikvm_args.cpp
+++ b/ikvm_args.cpp
@@ -8,12 +8,13 @@
namespace ikvm
{
-Args::Args(int argc, char* argv[]) : frameRate(30), calcFrameCRC{false},
+Args::Args(int argc, char* argv[]) : frameRate(30), subsampling(0), calcFrameCRC{false},
commandLine(argc, argv)
{
int option;
- const char* opts = "f:h:k:p:v:c";
+ const char* opts = "f:s:h:k:p:v:c";
struct option lopts[] = {{"frameRate", 1, 0, 'f'},
+ {"subsampling", 1, 0, 's'},
{"help", 0, 0, 'h'},
{"keyboard", 1, 0, 'k'},
{"mouse", 1, 0, 'p'},
@@ -30,6 +31,11 @@
if (frameRate < 0 || frameRate > 60)
frameRate = 30;
break;
+ case 's':
+ subsampling = (int)strtol(optarg, NULL, 0);
+ if (subsampling < 0 || subsampling > 1)
+ subsampling = 0;
+ break;
case 'h':
printUsage();
exit(0);
@@ -55,6 +61,7 @@
fprintf(stderr, "OpenBMC IKVM daemon\n");
fprintf(stderr, "Usage: obmc-ikvm [options]\n");
fprintf(stderr, "-f frame rate try this frame rate\n");
+ fprintf(stderr, "-s subsampling try this subsampling\n");
fprintf(stderr, "-h, --help show this message and exit\n");
fprintf(stderr, "-k device HID keyboard gadget device\n");
fprintf(stderr, "-p device HID mouse gadget device\n");
diff --git a/ikvm_args.hpp b/ikvm_args.hpp
index fbe19ad..bfd5507 100644
--- a/ikvm_args.hpp
+++ b/ikvm_args.hpp
@@ -72,6 +72,16 @@
}
/*
+ * @brief Get the video subsampling
+ *
+ * @return Value of the video subsampling
+ */
+ inline int getSubsampling() const
+ {
+ return subsampling;
+ }
+
+ /*
* @brief Get the path to the USB keyboard device
*
* @return Reference to the string storing the path to the keyboard device
@@ -120,6 +130,8 @@
* stream
*/
int frameRate;
+ /* @brief Desired subsampling (0: 444, 1: 420) */
+ int subsampling;
/* @brief Path to the USB keyboard device */
std::string keyboardPath;
/* @brief Path to the USB mouse device */
diff --git a/ikvm_manager.cpp b/ikvm_manager.cpp
index d56110d..33e7b17 100644
--- a/ikvm_manager.cpp
+++ b/ikvm_manager.cpp
@@ -8,7 +8,7 @@
Manager::Manager(const Args& args) :
continueExecuting(true), serverDone(false), videoDone(true),
input(args.getKeyboardPath(), args.getPointerPath()),
- video(args.getVideoPath(), input, args.getFrameRate()),
+ video(args.getVideoPath(), input, args.getFrameRate(), args.getSubsampling()),
server(args, input, video)
{
}
diff --git a/ikvm_video.cpp b/ikvm_video.cpp
index 8303170..5159b25 100644
--- a/ikvm_video.cpp
+++ b/ikvm_video.cpp
@@ -30,9 +30,10 @@
using namespace sdbusplus::xyz::openbmc_project::Common::File::Error;
using namespace sdbusplus::xyz::openbmc_project::Common::Device::Error;
-Video::Video(const std::string& p, Input& input, int fr) :
+Video::Video(const std::string& p, Input& input, int fr, int sub) :
resizeAfterOpen(false), timingsError(false), fd(-1), frameRate(fr),
- lastFrameIndex(-1), height(600), width(800), input(input), path(p)
+ lastFrameIndex(-1), height(600), width(800), subSampling(sub),
+ input(input), path(p)
{
}
@@ -378,6 +379,7 @@
v4l2_capability cap;
v4l2_format fmt;
v4l2_streamparm sparm;
+ v4l2_control ctrl;
if (fd >= 0)
{
@@ -444,6 +446,16 @@
entry("ERROR=%s", strerror(errno)));
}
+ ctrl.id = V4L2_CID_JPEG_CHROMA_SUBSAMPLING;
+ ctrl.value = subSampling
+ ? V4L2_JPEG_CHROMA_SUBSAMPLING_420 : V4L2_JPEG_CHROMA_SUBSAMPLING_444;
+ rc = ioctl(fd, VIDIOC_S_CTRL, &ctrl);
+ if (rc < 0)
+ {
+ log<level::WARNING>("Failed to set video jpeg subsampling",
+ entry("ERROR=%s", strerror(errno)));
+ }
+
height = fmt.fmt.pix.height;
width = fmt.fmt.pix.width;
diff --git a/ikvm_video.hpp b/ikvm_video.hpp
index fb8c5da..23c58a7 100644
--- a/ikvm_video.hpp
+++ b/ikvm_video.hpp
@@ -23,7 +23,7 @@
* @param[in] input - Reference to the Input object
* @param[in] fr - desired frame rate of the video
*/
- Video(const std::string& p, Input& input, int fr = 30);
+ Video(const std::string& p, Input& input, int fr = 30, int sub = 0);
~Video();
Video(const Video&) = default;
Video& operator=(const Video&) = default;
@@ -93,6 +93,24 @@
{
return width;
}
+ /*
+ * @brief Gets the subsampling of the video frame
+ *
+ * @return Value of the subsampling of video frame, 1:420/0:444
+ */
+ inline int getSubsampling() const
+ {
+ return subSampling;
+ }
+ /*
+ * @brief Sets the subsampling of the video frame
+ *
+ * @return Value of the subsampling of video frame, 1:420/0:444
+ */
+ inline void setSubsampling(int _sub)
+ {
+ subSampling = _sub;
+ }
/* @brief Number of bits per component of a pixel */
static const int bitsPerSample;
@@ -141,6 +159,8 @@
size_t height;
/* @brief Width in pixels of the video frame */
size_t width;
+ /* @brief jpeg's subsampling, 1:420/0:444 */
+ int subSampling;
/* @brief Reference to the Input object */
Input& input;
/* @brief Path to the V4L2 video device */