From eedfcdaccea09d129c974e7527f760af4d5bec5b Mon Sep 17 00:00:00 2001
From: Lev Zelenskiy <lev.zelenskiy@nokia.com>
Date: Tue, 31 Jul 2012 17:20:09 +1000
Subject: [PATCH] Change the way camera format is selected.

Build list of supported formats before starting directshow graph.
Select first available format supported by both device and surface.
Force DirectShow to do color space conversion instead of using QImage.

Change-Id: I8f946cc7c2693eea0135981e899003b453bd8784
Reviewed-by: Michael Goddard <michael.goddard@nokia.com>
Reviewed-by: Jonas Rabbe <jonas.rabbe@gmail.com>
Reviewed-by: Dmytro Poplavskiy <dmytro.poplavskiy@nokia.com>
---
 src/plugins/directshow/camera/dscamerasession.cpp | 56 +++++++++++++++--------
 1 file changed, 36 insertions(+), 20 deletions(-)

diff --git a/src/plugins/directshow/camera/dscamerasession.cpp b/src/plugins/directshow/camera/dscamerasession.cpp
index 71151b5..8b0011d 100644
--- a/src/plugins/directshow/camera/dscamerasession.cpp
+++ b/src/plugins/directshow/camera/dscamerasession.cpp
@@ -191,9 +191,7 @@ DSCameraSession::DSCameraSession(QObject *parent)
 
     m_output = 0;
     m_surface = 0;
-    m_windowSize = QSize(320,240);
-    pixelF = QVideoFrame::Format_RGB24;
-    actualFormat = QVideoSurfaceFormat(m_windowSize,pixelF);
+    pixelF = QVideoFrame::Format_Invalid;
 
     graph = false;
     active = false;
@@ -499,27 +497,33 @@ void DSCameraSession::record()
     }
 
     if(m_surface) {
-        bool match = false;
 
-        if (!m_surface->isFormatSupported(actualFormat)) {
-            QList<QVideoFrame::PixelFormat> fmts;
+        if (!graph)
+            graph = createFilterGraph();
+
+        if (types.isEmpty()) {
+            if (pixelF == QVideoFrame::Format_Invalid)
+                pixelF = QVideoFrame::Format_RGB32;
+            if (!m_windowSize.isValid())
+                m_windowSize = QSize(320, 240);
+        }
+        actualFormat = QVideoSurfaceFormat(m_windowSize, pixelF);
+
+        if (!m_surface->isFormatSupported(actualFormat) && !types.isEmpty()) {
+            // enumerate through camera formats
+            QList<QVideoFrame::PixelFormat> fmts = m_surface->supportedPixelFormats();
             foreach(QVideoFrame::PixelFormat f, types) {
                 if (fmts.contains(f)) {
-                    match = true;
                     pixelF = f;
-                    actualFormat = QVideoSurfaceFormat(m_windowSize,pixelF);
+                    if (!resolutions[pixelF].contains(m_windowSize)) {
+                        Q_ASSERT(!resolutions[pixelF].isEmpty());
+                        m_windowSize = resolutions[pixelF].first();
+                    }
+                    actualFormat = QVideoSurfaceFormat(m_windowSize, pixelF);
                     break;
                 }
             }
         }
-        if (!m_surface->isFormatSupported(actualFormat) && !match) {
-            // fallback
-            if (types.contains(QVideoFrame::Format_RGB24)) {
-                // get RGB24 from camera and convert to RGB32 for surface!
-                pixelF = QVideoFrame::Format_RGB32;
-                actualFormat = QVideoSurfaceFormat(m_windowSize,pixelF);
-            }
-        }
 
         if (m_surface->isFormatSupported(actualFormat)) {
             m_surface->start(actualFormat);
@@ -589,9 +593,9 @@ void DSCameraSession::captureFrame()
             mutex.lock();
 
             image = QImage(frames.at(0)->buffer,m_windowSize.width(),m_windowSize.height(),
-                    QImage::Format_RGB888).rgbSwapped().mirrored(true);
+                    QImage::Format_RGB32).rgbSwapped().mirrored(true);
 
-            QVideoFrame frame(image.convertToFormat(QImage::Format_RGB32));
+            QVideoFrame frame(image);
             frame.setStartTime(frames.at(0)->time);
 
             mutex.unlock();
@@ -762,8 +766,8 @@ bool DSCameraSession::createFilterGraph()
     pSG->SetBufferSamples(TRUE);
     pSG->SetCallback(StillCapCB, 1);
 
+    updateProperties();
     CoUninitialize();
-
     return true;
 }
 
@@ -849,6 +853,18 @@ void DSCameraSession::updateProperties()
         }
     }
     pConfig->Release();
+
+    if (!types.isEmpty()) {
+        // Add RGB formats and let directshow do color space conversion if required.
+        if (!types.contains(QVideoFrame::Format_RGB24)) {
+            types.append(QVideoFrame::Format_RGB24);
+            resolutions.insert(QVideoFrame::Format_RGB24, resolutions[types.first()]);
+        }
+        if (!types.contains(QVideoFrame::Format_RGB32)) {
+            types.append(QVideoFrame::Format_RGB32);
+            resolutions.insert(QVideoFrame::Format_RGB32, resolutions[types.first()]);
+        }
+    }
 }
 
 bool DSCameraSession::setProperties()
@@ -913,7 +929,7 @@ bool DSCameraSession::setProperties()
     am_media_type.majortype = MEDIATYPE_Video;
 
     if (actualFormat.pixelFormat() == QVideoFrame::Format_RGB32)
-        am_media_type.subtype = MEDIASUBTYPE_RGB24;
+        am_media_type.subtype = MEDIASUBTYPE_RGB32;
     else if (actualFormat.pixelFormat() == QVideoFrame::Format_RGB24)
         am_media_type.subtype = MEDIASUBTYPE_RGB24;
     else if (actualFormat.pixelFormat() == QVideoFrame::Format_YUYV)
-- 
2.7.4