qvidcap: add histogram supporthisto

Press 'S' to see histogram information of the current frame.

Signed-off-by: Hans Verkuil <hansverk@cisco.com>

4 files changed, 202 insertions, 0 deletions

diff --git a/utils/qvidcap/capture-win-gl.cpp b/utils/qvidcap/capture-win-gl.cpp
index 4ef7d276..ce206f77 100644
--- a/utils/qvidcap/capture-win-gl.cpp
+++ b/utils/qvidcap/capture-win-gl.cpp
@@ -195,6 +195,7 @@ CaptureGLWin::CaptureGLWin(QScrollArea *sa, QWidget *parent) :
 	m_singleStep(false),
 	m_singleStepStart(0),
 	m_singleStepNext(false),
+	m_showHistogram(false),
 	m_screenTextureCount(0),
 	m_program(0),
 	m_curSize(),
@@ -627,6 +628,9 @@ void CaptureGLWin::keyPressEvent(QKeyEvent *event)
 		checkSubMenuItem(m_quantMenu, m_overrideQuantization);
 		updateShader();
 		return;
+	case Qt::Key_S:
+		m_showHistogram = true;
+		return;
 	case Qt::Key_X:
 		cycleMenu(m_overrideXferFunc, m_origXferFunc,
 			  xfer_funcs, hasShift, hasCtrl);
@@ -1456,6 +1460,181 @@ void CaptureGLWin::tpgUpdateFrame()
 	m_updateShader = true;
 }
 
+static unsigned components[4][256];
+
+static void countPlane(unsigned plane, const __u8 *p, unsigned size, unsigned step)
+{
+	for (unsigned i = 0; i < size; i += step, p += step)
+		components[plane][*p]++;
+}
+
+void CaptureGLWin::showHistogram()
+{
+	const __u8 *p = m_curData[0];
+	unsigned size = m_curSize[0];
+	unsigned halfsize = size / 2;
+	bool has_alpha = false;
+	unsigned min_cnt = m_v4l_fmt.g_width() * m_v4l_fmt.g_height() * m_histThreshold / 100;
+
+	memset(components, 0, sizeof(components));
+
+	switch (m_v4l_fmt.g_pixelformat()) {
+	case V4L2_PIX_FMT_YUYV:
+		countPlane(0, p, size, 2);
+		countPlane(1, p + 1, size - 1, 4);
+		countPlane(2, p + 3, size - 3, 4);
+		break;
+	case V4L2_PIX_FMT_YVYU:
+		countPlane(0, p, size, 2);
+		countPlane(1, p + 3, size - 3, 4);
+		countPlane(2, p + 1, size - 1, 4);
+		break;
+	case V4L2_PIX_FMT_UYVY:
+		countPlane(1, p, size, 4);
+		countPlane(0, p + 1, size - 1, 2);
+		countPlane(2, p + 2, size - 2, 4);
+		break;
+	case V4L2_PIX_FMT_VYUY:
+		countPlane(2, p, size, 4);
+		countPlane(0, p + 1, size - 1, 2);
+		countPlane(1, p + 2, size - 2, 4);
+		break;
+
+	case V4L2_PIX_FMT_NV16:
+		countPlane(0, p, halfsize, 1);
+		p += halfsize;
+		countPlane(1, p, halfsize, 2);
+		countPlane(2, p + 1, halfsize - 1, 2);
+		break;
+	case V4L2_PIX_FMT_NV61:
+		countPlane(0, p, halfsize, 1);
+		p += halfsize;
+		countPlane(2, p, halfsize, 2);
+		countPlane(1, p + 1, halfsize - 1, 2);
+		break;
+	case V4L2_PIX_FMT_NV12M:
+	case V4L2_PIX_FMT_NV16M:
+		countPlane(0, p, size, 1);
+		countPlane(1, m_curData[1], m_curSize[1], 2);
+		countPlane(2, m_curData[1] + 1, m_curSize[1] - 1, 2);
+		break;
+	case V4L2_PIX_FMT_NV21M:
+	case V4L2_PIX_FMT_NV61M:
+		countPlane(0, p, size, 1);
+		countPlane(2, m_curData[1], m_curSize[1], 2);
+		countPlane(1, m_curData[1] + 1, m_curSize[1] - 1, 2);
+		break;
+
+	case V4L2_PIX_FMT_NV12:
+		countPlane(0, p, size / 3 * 2, 1);
+		p += size / 3 * 2;
+		size /= 3;
+		countPlane(1, p, size, 2);
+		countPlane(2, p + 1, size - 1, 2);
+		break;
+	case V4L2_PIX_FMT_NV21:
+		countPlane(0, p, size / 3 * 2, 1);
+		p += size / 3 * 2;
+		size /= 3;
+		countPlane(2, p, size, 2);
+		countPlane(1, p + 1, size - 1, 2);
+		break;
+
+	case V4L2_PIX_FMT_NV24:
+		countPlane(0, p, size / 3, 1);
+		p += size / 3;
+		size -= size / 3;
+		countPlane(1, p, size, 2);
+		countPlane(2, p + 1, size - 1, 2);
+		break;
+	case V4L2_PIX_FMT_NV42:
+		countPlane(0, p, size / 3, 1);
+		p += size / 3;
+		size -= size / 3;
+		countPlane(2, p, size, 2);
+		countPlane(1, p + 1, size - 1, 2);
+		break;
+
+	case V4L2_PIX_FMT_RGB24:
+	case V4L2_PIX_FMT_HSV24:
+		countPlane(0, p, size, 3);
+		countPlane(1, p + 1, size - 1, 3);
+		countPlane(2, p + 2, size - 2, 3);
+		break;
+	case V4L2_PIX_FMT_BGR24:
+		countPlane(2, p, size, 3);
+		countPlane(1, p + 1, size - 1, 3);
+		countPlane(0, p + 2, size - 2, 3);
+		break;
+	case V4L2_PIX_FMT_ARGB32:
+		countPlane(3, p, size, 4);
+		has_alpha = true;
+		/* fall-through */
+	case V4L2_PIX_FMT_RGB32:
+	case V4L2_PIX_FMT_XRGB32:
+	case V4L2_PIX_FMT_HSV32:
+		countPlane(0, p + 1, size - 1, 4);
+		countPlane(1, p + 2, size - 2, 4);
+		countPlane(2, p + 3, size - 3, 4);
+		break;
+	case V4L2_PIX_FMT_ABGR32:
+		countPlane(3, p + 3, size - 3, 4);
+		has_alpha = true;
+		/* fall-through */
+	case V4L2_PIX_FMT_BGR32:
+	case V4L2_PIX_FMT_XBGR32:
+		countPlane(0, p + 2, size - 2, 4);
+		countPlane(1, p + 1, size - 1, 4);
+		countPlane(2, p, size, 4);
+		break;
+	default:
+		fprintf(stderr, "Histogram is not supported for format '%s' %s\n",
+			fcc2s(m_v4l_fmt.g_pixelformat()).c_str(),
+			pixfmt2s(m_v4l_fmt.g_pixelformat()).c_str());
+		return;
+	}
+
+	switch (m_v4l_fmt.g_pixelformat()) {
+	case V4L2_PIX_FMT_YUYV:
+	case V4L2_PIX_FMT_YVYU:
+	case V4L2_PIX_FMT_UYVY:
+	case V4L2_PIX_FMT_VYUY:
+	case V4L2_PIX_FMT_NV16:
+	case V4L2_PIX_FMT_NV61:
+	case V4L2_PIX_FMT_NV12M:
+	case V4L2_PIX_FMT_NV16M:
+	case V4L2_PIX_FMT_NV21M:
+	case V4L2_PIX_FMT_NV61M:
+	case V4L2_PIX_FMT_NV12:
+	case V4L2_PIX_FMT_NV21:
+	case V4L2_PIX_FMT_NV24:
+	case V4L2_PIX_FMT_NV42:
+		printf("\n                  Y         U         V");
+		break;
+
+	case V4L2_PIX_FMT_HSV24:
+	case V4L2_PIX_FMT_HSV32:
+		printf("\n                  H         S         V");
+		break;
+	default:
+		printf("\n                  R         G         B");
+		break;
+	}
+	if (has_alpha)
+		printf("         A");
+	printf("\n");
+	for (unsigned i = 0; i < 256; i++) {
+		if (components[0][i] <= min_cnt && components[1][i] <= min_cnt &&
+		    components[2][i] <= min_cnt && components[3][i] <= min_cnt)
+			continue;
+		printf("%3d/0x%02x: %9u %9u %9u",
+		       i, i, components[0][i], components[1][i], components[2][i]);
+		if (has_alpha)
+			printf(" %9u", components[3][i]);
+		printf("\n");
+	}
+}
+
 void CaptureGLWin::initializeGL()
 {
 	initializeOpenGLFunctions();
@@ -1544,6 +1723,11 @@ void CaptureGLWin::paintGL()
 	if (!supportedFmt(m_v4l_fmt.g_pixelformat()))
 		return;
 
+	if (m_showHistogram) {
+		m_showHistogram = false;
+		showHistogram();
+	}
+
 	switch (m_v4l_fmt.g_pixelformat()) {
 	case V4L2_PIX_FMT_YUYV:
 	case V4L2_PIX_FMT_YVYU:
diff --git a/utils/qvidcap/capture-win-gl.h b/utils/qvidcap/capture-win-gl.h
index d446c1ff..54aea966 100644
--- a/utils/qvidcap/capture-win-gl.h
+++ b/utils/qvidcap/capture-win-gl.h
@@ -83,6 +83,7 @@ public:
 	void setOverrideHeight(__u32 h);
 	void setCount(unsigned cnt) { m_cnt = cnt; }
 	void setReportTimings(bool report) { m_reportTimings = report; }
+	void setHistThreshold(unsigned threshold) { m_histThreshold = threshold; }
 	void setVerbose(bool verbose) { m_verbose = verbose; }
 	void setOverridePixelFormat(__u32 fmt) { m_overridePixelFormat = fmt; }
 	void setOverrideField(__u32 field) { m_overrideField = field; }
@@ -136,6 +137,7 @@ private:
 	void configureTexture(size_t idx);
 	void initImageFormat();
 	void updateOrigValues();
+	void showHistogram();
 	void updateShader();
 	void changeShader();
 
@@ -175,6 +177,7 @@ private:
 	unsigned m_imageSize;
 	bool m_verbose;
 	bool m_reportTimings;
+	unsigned m_histThreshold;
 	bool m_is_sdtv;
 	v4l2_std_id m_std;
 	bool m_is_rgb;
@@ -209,6 +212,7 @@ private:
 	bool m_singleStep;
 	unsigned m_singleStepStart;
 	bool m_singleStepNext;
+	bool m_showHistogram;
 
 	QTimer *m_timer;
 	int m_screenTextureCount;
diff --git a/utils/qvidcap/qvidcap.1.in b/utils/qvidcap/qvidcap.1.in
index bc1d1113..2201a6a8 100644
--- a/utils/qvidcap/qvidcap.1.in
+++ b/utils/qvidcap/qvidcap.1.in
@@ -66,6 +66,10 @@ Be more verbose
 \fB\-R\fR, \fB\-\-raw\fR
 Open device in raw mode
 .TP
+\fB\-\-hist\-threshold\fR=\fI<perc>\fR
+Histogram threshold: only show component values when used
+in <perc> percent of all pixels (default=0).
+.TP
 \fB\--opengl\fR
 Force openGL to display the video
 .TP
@@ -193,6 +197,9 @@ Cycle forwards through all the supported quantization ranges.
 With Shift pressed: cycle backwards.
 With Ctrl pressed: restore the original quantization range.
 .TP
+\fIS\fR
+Show histogram statistics.
+.TP
 \fIRight-Click\fR
 Open menu.
 .TP
diff --git a/utils/qvidcap/qvidcap.cpp b/utils/qvidcap/qvidcap.cpp
index d29b4405..bf3a2009 100644
--- a/utils/qvidcap/qvidcap.cpp
+++ b/utils/qvidcap/qvidcap.cpp
@@ -64,6 +64,8 @@ static void usage()
 	       "  -t, --timings            report frame render timings\n"
 	       "  -v, --verbose            be more verbose\n"
 	       "  -R, --raw                open device in raw mode\n"
+	       "  --hist-threshold=<perc>  histogram threshold: only show component values when used\n"
+	       "                           in <perc> percent of all pixels (default=0)\n"
 	       "\n"
 	       "  --opengl                 force openGL to display the video\n"
 	       "  --opengles               force openGL ES to display the video\n"
@@ -437,6 +439,7 @@ int main(int argc, char **argv)
 	unsigned v4l2_bufs = 4;
 	bool single_step = false;
 	unsigned single_step_start = 1;
+	unsigned hist_threshold = 0;
 	int port = 0;
 	bool info_option = false;
 	bool report_timings = false;
@@ -648,6 +651,9 @@ int main(int argc, char **argv)
 		} else if (isOptArg(args[i], "--buffers", "-b")) {
 			if (!processOption(args, i, v4l2_bufs))
 				return 0;
+		} else if (isOptArg(args[i], "--hist-threshold")) {
+			if (!processOption(args, i, hist_threshold))
+				return 0;
 		} else if (isOption(args[i], "--single-step", "-s")) {
 			single_step = true;
 			single_step_start = 1;
@@ -737,6 +743,7 @@ int main(int argc, char **argv)
 	win.setFps(fps);
 	win.setFormat(format);
 	win.setReportTimings(report_timings);
+	win.setHistThreshold(hist_threshold);
 	win.setCount(test ? test : cnt);
 	if (mode == AppModeTest) {
 		win.setModeTest(test);