added video writer quality, which user may change dynamically in the case of...

added video writer quality, which user may change dynamically in the case of motion jpeg; enabled NEON intrinsics in the encoder

modules/videoio/include/opencv2/videoio.hpp

@@ -376,6 +376,9 @@ enum { CAP_INTELPERC_DEPTH_MAP              = 0, // Each pixel is a 16-bit integ
        CAP_INTELPERC_IMAGE                  = 3
      };
 
+enum { VIDEOWRITER_PROP_QUALITY = 1,    // Quality (0..100%) of the videostream encoded
+       VIDEOWRITER_PROP_FRAMEBYTES = 2, // (Read-only): Size of just encoded video frame
+     };
 
 class IVideoCapture;
 
@@ -642,6 +645,25 @@ public:
      */
     CV_WRAP virtual void write(const Mat& image);
 
+    /** @brief Sets a property in the VideoWriter.
+
+     @param propId Property identifier. It can be one of the following:
+     -   **VIDEOWRITER_PROP_QUALITY** Quality (0..100%) of the videostream encoded. Can be adjusted dynamically in some codecs.
+     @param value Value of the property.
+     */
+    CV_WRAP virtual bool set(int propId, double value);
+
+    /** @brief Returns the specified VideoWriter property
+
+     @param propId Property identifier. It can be one of the following:
+     -   **VIDEOWRITER_PROP_QUALITY** Current quality of the encoded videostream.
+     -   **VIDEOWRITER_PROP_FRAMEBYTES** (Read-only) Size of just encoded video frame; note that the encoding order may be different from representation order.
+
+     **Note**: When querying a property that is not supported by the backend used by the VideoWriter
+     class, value 0 is returned.
+     */
+    CV_WRAP virtual double get(int propId) const;
+
     /** @brief Concatenates 4 chars to a fourcc code
 
     This static method constructs the fourcc code of the codec to be used in the constructor

modules/videoio/src/cap.cpp

@@ -705,6 +705,21 @@ bool VideoWriter::isOpened() const
     return !iwriter.empty() || !writer.empty();
 }
 
+
+bool VideoWriter::set(int propId, double value)
+{
+    if (!iwriter.empty())
+        return iwriter->setProperty(propId, value);
+    return false;
+}
+
+double VideoWriter::get(int propId) const
+{
+    if (!iwriter.empty())
+        return iwriter->getProperty(propId);
+    return 0.;
+}
+
 void VideoWriter::write(const Mat& image)
 {
     if( iwriter )

modules/videoio/src/cap_mjpeg_encoder.cpp

@@ -42,9 +42,8 @@
 #include "precomp.hpp"
 #include <vector>
 
-//#define WITH_NEON
-#ifdef WITH_NEON
-#include "arm_neon.h"
+#if CV_NEON
+#define WITH_NEON
 #endif
 
 namespace cv
@@ -381,7 +380,7 @@ public:
         outfps = cvRound(fps);
         width = size.width;
         height = size.height;
-        quality = 8;
+        quality = 75;
         rawstream = false;
         channels = iscolor ? 3 : 1;
 
@@ -592,12 +591,31 @@ public:
         }
     }
 
+    double getProperty(int propId) const
+    {
+        if( propId == VIDEOWRITER_PROP_QUALITY )
+            return quality;
+        if( propId == VIDEOWRITER_PROP_FRAMEBYTES )
+            return frameSize.empty() ? 0. : (double)frameSize.back();
+        return 0.;
+    }
+
+    bool setProperty(int propId, double value)
+    {
+        if( propId == VIDEOWRITER_PROP_QUALITY )
+        {
+            quality = value;
+            return true;
+        }
+        return false;
+    }
+
     void writeFrameData( const uchar* data, int step, int colorspace, int input_channels );
 
 protected:
     int outfps;
     int width, height, channels;
-    int quality;
+    double quality;
     size_t moviPointer;
     std::vector<size_t> frameOffset, frameSize, AVIChunkSizeIndex, frameNumIndexes;
     bool rawstream;
@@ -1116,11 +1134,12 @@ void MotionJpegWriter::writeFrameData( const uchar* data, int step, int colorspa
     const int UV_step = 16;
     int u_plane_ofs = step*height;
     int v_plane_ofs = u_plane_ofs + step*height;
+    double _quality = quality*0.01*max_quality;
 
-    if( quality < 1 ) quality = 1;
-    if( quality > max_quality ) quality = max_quality;
+    if( _quality < 1. ) _quality = 1.;
+    if( _quality > max_quality ) _quality = max_quality;
 
-    double inv_quality = 1./quality;
+    double inv_quality = 1./_quality;
 
     // Encode header
     strm.putBytes( (const uchar*)jpegHeader, sizeof(jpegHeader) - 1 );

modules/videoio/src/precomp.hpp

@@ -166,7 +166,7 @@ namespace cv
     public:
         virtual ~IVideoCapture() {}
         virtual double getProperty(int) const { return 0; }
-        virtual bool setProperty(int, double) { return 0; }
+        virtual bool setProperty(int, double) { return false; }
         virtual bool grabFrame() = 0;
         virtual bool retrieveFrame(int, OutputArray) = 0;
         virtual bool isOpened() const = 0;
@@ -178,7 +178,7 @@ namespace cv
     public:
         virtual ~IVideoWriter() {}
         virtual double getProperty(int) const { return 0; }
-        virtual bool setProperty(int, double) { return 0; }
+        virtual bool setProperty(int, double) { return false; }
 
         virtual bool isOpened() const = 0;
         virtual void write(InputArray) = 0;