整理代码

video/v4l2/InputFormat.cpp

@@ -0,0 +1,83 @@
+/*
+ *******************************************************************************
+ *                                   INCLUDE
+ *******************************************************************************
+ */
+#include "InputFormat.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <linux/videodev2.h>
+#include <Poco/Exception.h>
+#include <Poco/Format.h>
+
+namespace Video
+{
+namespace V4L2
+{
+/*
+ *******************************************************************************
+ *                                CLASS DEFINE
+ *******************************************************************************
+ */
+void InputFormat::enumerate(const std::string& deviceName, InputFormat::Collection& c)
+{
+    int fd = open(deviceName.c_str(), O_RDWR);
+    if (fd < 0)
+        throw Poco::InvalidAccessException(Poco::format("Video::V4l2::InputFormat: Open %s FAIL: %d", deviceName, fd));
+
+    struct v4l2_fmtdesc fmt;
+    fmt.type  = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+    fmt.index = 0;
+    while (ioctl(fd, VIDIOC_ENUM_FMT, &fmt) == 0)
+    {
+        InputFormat format;
+        format.pixelFormat = fmt.pixelformat;
+        format.description = (char*)fmt.description;
+
+        struct v4l2_frmsizeenum frmsize;
+        frmsize.index        = 0;
+        frmsize.pixel_format = fmt.pixelformat;
+        while (ioctl(fd, VIDIOC_ENUM_FRAMESIZES, &frmsize) == 0)
+        {
+            switch (frmsize.type)
+            {
+            case V4L2_FRMSIZE_TYPE_DISCRETE:
+            {
+                struct v4l2_frmivalenum frameinterval;
+
+                frameinterval.width        = frmsize.discrete.width;
+                frameinterval.height       = frmsize.discrete.height;
+                frameinterval.pixel_format = fmt.pixelformat;
+                frameinterval.type         = V4L2_FRMIVAL_TYPE_DISCRETE;
+                frameinterval.index        = 0;
+                while (ioctl(fd, VIDIOC_ENUM_FRAMEINTERVALS, &frameinterval) == 0)
+                {
+                    InputFormat::Resolution resolution;
+                    resolution.width  = frameinterval.width;
+                    resolution.height = frameinterval.height;
+                    resolution.fps    = frameinterval.discrete.denominator / frameinterval.discrete.numerator;
+                    format.resolutions.push_back(resolution);
+
+                    frameinterval.index++;
+                }
+            }
+            break;
+            }
+
+            frmsize.index++;
+        }
+
+        format.resolutions.sort([](auto& a, auto& b) { return a.width * a.height > b.width * b.height; });
+
+        c.push_back(format);
+        fmt.index++;
+    }
+
+    close(fd);
+}
+}
+}