tightPng: Add initial tightPng encoding support.

http://wiki.qemu.org/VNC_Tight_PNGSigned-off-by: Joel Martin <github@martintribe.org>
Signed-off-by: Christian Beier <dontmind@freeshell.org>

CMakeLists.txt

@@ -15,6 +15,7 @@ include_directories(${CMAKE_SOURCE_DIR} ${CMAKE_BINARY_DIR} ${CMAKE_SOURCE_DIR}/
 
 find_package(ZLIB)
 find_package(JPEG)
+find_package(PNG)
 find_package(SDL)
 find_package(GnuTLS)
 find_package(Threads)
@@ -30,6 +31,9 @@ endif(ZLIB_FOUND)
 if(JPEG_FOUND)
   set(LIBVNCSERVER_HAVE_LIBJPEG 1)
 endif(JPEG_FOUND)
+if(PNG_FOUND)
+  set(LIBVNCSERVER_HAVE_LIBPNG 1)
+endif(PNG_FOUND)
 option(LIBVNCSERVER_ALLOW24BPP "Allow 24 bpp" ON)
 if(GNUTLS_FOUND)
   set(LIBVNCSERVER_WITH_CLIENT_TLS 1)
@@ -142,12 +146,21 @@ endif(ZLIB_FOUND)
 if(JPEG_FOUND)
   add_definitions(-DLIBVNCSERVER_HAVE_LIBJPEG)
   include_directories(${JPEG_INCLUDE_DIR})
-  set(LIBVNCSERVER_SOURCES
-    ${LIBVNCSERVER_SOURCES}
-    ${LIBVNCSERVER_DIR}/tight.c
-  )
+  set(TIGHT_C ${LIBVNCSERVER_DIR}/tight.c)
 endif(JPEG_FOUND)
 
+if(PNG_FOUND)
+  add_definitions(-DLIBVNCSERVER_HAVE_LIBPNG)
+  include_directories(${PNG_INCLUDE_DIR})
+  set(TIGHT_C ${LIBVNCSERVER_DIR}/tight.c)
+endif(PNG_FOUND)
+
+
+set(LIBVNCSERVER_SOURCES
+    ${LIBVNCSERVER_SOURCES}
+    ${TIGHT_C}
+)
+
 if(TIGHTVNC_FILETRANSFER)
   set(LIBVNCSERVER_SOURCES
     ${LIBVNCSERVER_SOURCES}
@@ -174,6 +187,7 @@ target_link_libraries(vncserver
                       ${ADDITIONAL_LIBS}
                       ${ZLIB_LIBRARIES}
                       ${JPEG_LIBRARIES}
+		      ${PNG_LIBRARIES}
                       ${SDL_LIBRARY}
 )
 

configure.ac

@@ -578,6 +578,60 @@ ftp://ftp.uu.net/graphics/jpeg/
 	fi
 fi
 
+AC_ARG_WITH(png,
+[  --without-png           disable support for png]
+[  --with-png=DIR          use png include/library files in DIR],,)
+
+# At this point:
+#	no png on command line    with_png=""
+#	-with-png                 with_png="yes"
+#	-without-png              with_png="no"
+#	-with-png=/foo/dir        with_png="/foo/dir"
+
+if test "x$with_png" != "xno"; then
+	if test ! -z "$with_png" -a "x$with_png" != "xyes"; then
+		# add user supplied directory to flags:
+		saved_CPPFLAGS="$CPPFLAGS"
+		saved_LDFLAGS="$LDFLAGS"
+		CPPFLAGS="$CPPFLAGS -I$with_png/include"
+		LDFLAGS="$LDFLAGS -L$with_png/lib"
+		if test "x$ld_minus_R" = "xno"; then
+			:
+		elif test "x$GCC" = "xyes"; then
+			# this is not complete... in general a rat's nest.
+			LDFLAGS="$LDFLAGS -Xlinker -R$with_png/lib"
+		else
+			LDFLAGS="$LDFLAGS -R$with_png/lib"
+		fi
+	fi
+	AC_CHECK_HEADER(png.h, HAVE_PNGLIB_H="true")
+	if test "x$HAVE_PNGLIB_H" = "xtrue"; then
+		AC_CHECK_LIB(png, png_create_write_struct, , HAVE_PNGLIB_H="")
+	fi
+	if test ! -z "$with_png" -a "x$with_png" != "xyes"; then
+		if test "x$HAVE_PNGLIB_H" != "xtrue"; then
+			# restore old flags on failure:
+			CPPFLAGS="$saved_CPPFLAGS"
+			LDFLAGS="$saved_LDFLAGS"
+		fi
+	fi
+	if test "$build_x11vnc" = "yes"; then
+		if test "x$HAVE_PNGLIB_H" != "xtrue"; then
+			AC_MSG_WARN([
+==========================================================================
+*** The libpng compression library was not found. ***
+This may lead to reduced performance, especially over slow links.
+If libpng is in a non-standard location use --with-png=DIR to
+indicate the header file is in DIR/include/png.h and the library
+in DIR/lib/libpng.a.  A copy of libpng may be obtained from:
+http://www.libpng.org/pub/png/libpng.html
+==========================================================================
+])
+			sleep 5
+		fi
+	fi
+fi
+
 AC_ARG_WITH(libz,
 [  --without-libz          disable support for deflate],,)
 AC_ARG_WITH(zlib,
@@ -654,6 +708,7 @@ AM_CONDITIONAL(WITH_TIGHTVNC_FILETRANSFER, test "$with_tightvnc_filetransfer" =
 
 AM_CONDITIONAL(HAVE_LIBZ, test ! -z "$HAVE_ZLIB_H")
 AM_CONDITIONAL(HAVE_LIBJPEG, test ! -z "$HAVE_JPEGLIB_H")
+AM_CONDITIONAL(HAVE_LIBPNG, test ! -z "$HAVE_PNGLIB_H")
 
 
 SDLCONFIG="sdl-config"

libvncserver/Makefile.am

@@ -29,7 +29,11 @@ EXTRA_DIST=tableinit24.c tableinittctemplate.c tabletranstemplate.c \
 if HAVE_LIBZ
 ZLIBSRCS = zlib.c zrle.c zrleoutstream.c zrlepalettehelper.c ../common/zywrletemplate.c
 if HAVE_LIBJPEG
-JPEGSRCS = tight.c
+TIGHTSRCS = tight.c
+else
+if HAVE_LIBPNG
+TIGHTSRCS = tight.c
+endif
 endif
 endif
 
@@ -37,7 +41,7 @@ LIB_SRCS = main.c rfbserver.c rfbregion.c auth.c sockets.c \
 	stats.c corre.c hextile.c rre.c translate.c cutpaste.c \
 	httpd.c cursor.c font.c \
 	draw.c selbox.c ../common/d3des.c ../common/vncauth.c cargs.c ../common/minilzo.c ultra.c scale.c \
-	$(ZLIBSRCS) $(JPEGSRCS) $(TIGHTVNCFILETRANSFERSRCS)
+	$(ZLIBSRCS) $(TIGHTSRCS) $(TIGHTVNCFILETRANSFERSRCS)
 
 libvncserver_la_SOURCES=$(LIB_SRCS)
 

libvncserver/rfbserver.c

@@ -358,10 +358,12 @@ rfbNewTCPOrUDPClient(rfbScreenInfoPtr rfbScreen,
       rfbScreen->clientHead = cl;
       UNLOCK(rfbClientListMutex);
 
-#ifdef LIBVNCSERVER_HAVE_LIBZ
+#if defined(LIBVNCSERVER_HAVE_LIBZ) || defined(LIBVNCSERVER_HAVE_LIBPNG)
       cl->tightQualityLevel = -1;
-#ifdef LIBVNCSERVER_HAVE_LIBJPEG
+#if defined(LIBVNCSERVER_HAVE_LIBJPEG) || defined(LIBVNCSERVER_HAVE_LIBPNG)
       cl->tightCompressLevel = TIGHT_DEFAULT_COMPRESSION;
+#endif
+#ifdef LIBVNCSERVER_HAVE_LIBJPEG
       {
 	int i;
 	for (i = 0; i < 4; i++)
@@ -917,6 +919,9 @@ rfbSendSupportedEncodings(rfbClientPtr cl)
 #endif
 #ifdef LIBVNCSERVER_HAVE_LIBJPEG
 	rfbEncodingTight,
+#endif
+#ifdef LIBVNCSERVER_HAVE_LIBPNG
+	rfbEncodingTightPng,
 #endif
 	rfbEncodingUltra,
 	rfbEncodingUltraZip,
@@ -1937,6 +1942,9 @@ rfbProcessClientNormalMessage(rfbClientPtr cl)
 #ifdef LIBVNCSERVER_HAVE_LIBJPEG
 	    case rfbEncodingTight:
 #endif
+#endif
+#ifdef LIBVNCSERVER_HAVE_LIBPNG
+	    case rfbEncodingTightPng:
 #endif
             /* The first supported encoding is the 'preferred' encoding */
                 if (cl->preferredEncoding == -1)
@@ -2026,11 +2034,11 @@ rfbProcessClientNormalMessage(rfbClientPtr cl)
 		}
                 break;
             default:
-#ifdef LIBVNCSERVER_HAVE_LIBZ
+#if defined(LIBVNCSERVER_HAVE_LIBZ) || defined(LIBVNCSERVER_HAVE_LIBPNG)
 		if ( enc >= (uint32_t)rfbEncodingCompressLevel0 &&
 		     enc <= (uint32_t)rfbEncodingCompressLevel9 ) {
 		    cl->zlibCompressLevel = enc & 0x0F;
-#ifdef LIBVNCSERVER_HAVE_LIBJPEG
+#if defined(LIBVNCSERVER_HAVE_LIBJPEG) || defined(LIBVNCSERVER_HAVE_LIBPNG)
 		    cl->tightCompressLevel = enc & 0x0F;
 		    rfbLog("Using compression level %d for client %s\n",
 			   cl->tightCompressLevel, cl->host);
@@ -2754,6 +2762,28 @@ rfbSendFramebufferUpdate(rfbClientPtr cl,
 	}
 	sraRgnReleaseIterator(i); i=NULL;
 #endif
+#endif
+#ifdef LIBVNCSERVER_HAVE_LIBPNG
+    } else if (cl->preferredEncoding == rfbEncodingTightPng) {
+	nUpdateRegionRects = 0;
+
+        for(i = sraRgnGetIterator(updateRegion); sraRgnIteratorNext(i,&rect);){
+            int x = rect.x1;
+            int y = rect.y1;
+            int w = rect.x2 - x;
+            int h = rect.y2 - y;
+            int n;
+            /* We need to count the number of rects in the scaled screen */
+            if (cl->screen!=cl->scaledScreen)
+                rfbScaledCorrection(cl->screen, cl->scaledScreen, &x, &y, &w, &h, "rfbSendFramebufferUpdate");
+	    n = rfbNumCodedRectsTight(cl, x, y, w, h);
+	    if (n == 0) {
+		nUpdateRegionRects = 0xFFFF;
+		break;
+	    }
+	    nUpdateRegionRects += n;
+	}
+	sraRgnReleaseIterator(i); i=NULL;
 #endif
     } else {
         nUpdateRegionRects = sraRgnCountRects(updateRegion);
@@ -2773,6 +2803,10 @@ rfbSendFramebufferUpdate(rfbClientPtr cl,
 	   /* Tight encoding counts the rectangles differently */
 	   && cl->preferredEncoding != rfbEncodingTight
 #endif
+#endif
+#ifdef LIBVNCSERVER_HAVE_LIBPNG
+	   /* Tight encoding counts the rectangles differently */
+	   && cl->preferredEncoding != rfbEncodingTightPng
 #endif
 	   && nUpdateRegionRects>cl->screen->maxRectsPerUpdate) {
 	    sraRegion* newUpdateRegion = sraRgnBBox(updateRegion);
@@ -2868,6 +2902,13 @@ rfbSendFramebufferUpdate(rfbClientPtr cl,
 	    break;
 #endif
 #endif
+#ifdef LIBVNCSERVER_HAVE_LIBPNG
+	case rfbEncodingTightPng:
+            /* TODO */
+	    if (!rfbSendRectEncodingTightPng(cl, x, y, w, h))
+	        goto updateFailed;
+	    break;
+#endif
 #ifdef LIBVNCSERVER_HAVE_LIBZ
        case rfbEncodingZRLE:
        case rfbEncodingZYWRLE:

libvncserver/stats.c

@@ -100,6 +100,7 @@ char *encodingName(uint32_t type, char *buf, int len) {
     case rfbEncodingHextile:            snprintf(buf, len, "hextile");     break;
     case rfbEncodingZlib:               snprintf(buf, len, "zlib");        break;
     case rfbEncodingTight:              snprintf(buf, len, "tight");       break;
+    case rfbEncodingTightPng:           snprintf(buf, len, "tightPng");    break;
     case rfbEncodingZlibHex:            snprintf(buf, len, "zlibhex");     break;
     case rfbEncodingUltra:              snprintf(buf, len, "ultra");       break;
     case rfbEncodingZRLE:               snprintf(buf, len, "ZRLE");        break;

rfb/rfb.h

@@ -542,7 +542,9 @@ typedef struct _rfbClientRec {
     struct z_stream_s compStream;
     rfbBool compStreamInited;
     uint32_t zlibCompressLevel;
-    /** the quality level is also used by ZYWRLE */
+#endif
+#if defined(LIBVNCSERVER_HAVE_LIBZ) || defined(LIBVNCSERVER_HAVE_LIBPNG)
+    /** the quality level is also used by ZYWRLE and TightPng */
     int tightQualityLevel;
 
 #ifdef LIBVNCSERVER_HAVE_LIBJPEG
@@ -550,6 +552,8 @@ typedef struct _rfbClientRec {
     z_stream zsStruct[4];
     rfbBool zsActive[4];
     int zsLevel[4];
+#endif
+#if defined(LIBVNCSERVER_HAVE_LIBJPEG) || defined(LIBVNCSERVER_HAVE_LIBPNG)
     int tightCompressLevel;
 #endif
 #endif
@@ -624,6 +628,9 @@ typedef struct _rfbClientRec {
   char *afterEncBuf;
   int afterEncBufSize;
   int afterEncBufLen;
+#if defined(LIBVNCSERVER_HAVE_LIBZ) || defined(LIBVNCSERVER_HAVE_LIBPNG)
+    uint32_t tightEncoding;  /* rfbEncodingTight or rfbEncodingTightPng */
+#endif
 } rfbClientRec, *rfbClientPtr;
 
 /**
@@ -800,7 +807,7 @@ extern rfbBool rfbSendRectEncodingUltra(rfbClientPtr cl, int x,int y,int w,int h
 extern rfbBool rfbSendRectEncodingZlib(rfbClientPtr cl, int x, int y, int w,
 				    int h);
 
-#ifdef LIBVNCSERVER_HAVE_LIBJPEG
+#if defined(LIBVNCSERVER_HAVE_LIBJPEG) || defined(LIBVNCSERVER_HAVE_LIBPNG)
 /* tight.c */
 
 #define TIGHT_DEFAULT_COMPRESSION  6
@@ -808,7 +815,13 @@ extern rfbBool rfbSendRectEncodingZlib(rfbClientPtr cl, int x, int y, int w,
 extern rfbBool rfbTightDisableGradient;
 
 extern int rfbNumCodedRectsTight(rfbClientPtr cl, int x,int y,int w,int h);
+
+#if defined(LIBVNCSERVER_HAVE_LIBJPEG)
 extern rfbBool rfbSendRectEncodingTight(rfbClientPtr cl, int x,int y,int w,int h);
+#endif
+#if defined(LIBVNCSERVER_HAVE_LIBPNG)
+extern rfbBool rfbSendRectEncodingTightPng(rfbClientPtr cl, int x,int y,int w,int h);
+#endif
 
 #endif
 #endif

rfb/rfbconfig.h.cmake

@@ -18,6 +18,9 @@
 /* Define to 1 if you have the `jpeg' library (-ljpeg). */
 #cmakedefine LIBVNCSERVER_HAVE_LIBJPEG  1 
 
+/* Define if you have the `png' library (-lpng). */
+#cmakedefine LIBVNCSERVER_HAVE_LIBPNG  1
+
 /* Define to 1 if you have the `pthread' library (-lpthread). */
 #cmakedefine LIBVNCSERVER_HAVE_LIBPTHREAD  1 
 

rfb/rfbproto.h

@@ -434,6 +434,7 @@ typedef struct {
 #define rfbEncodingHextile 5
 #define rfbEncodingZlib 6
 #define rfbEncodingTight 7
+#define rfbEncodingTightPng 0xFFFFFEFC /* -260 */
 #define rfbEncodingZlibHex 8
 #define rfbEncodingUltra 9
 #define rfbEncodingZRLE 16
@@ -704,7 +705,10 @@ typedef struct {
 #ifdef LIBVNCSERVER_HAVE_LIBZ
 
 /*- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
- * Tight Encoding.
+ * Tight and TightPng Encoding.
+ *
+ *-- TightPng is like Tight but basic compression is not used, instead PNG
+ *   data is sent.
  *
  *-- The first byte of each Tight-encoded rectangle is a "compression control
  *   byte". Its format is as follows (bit 0 is the least significant one):
@@ -715,8 +719,9 @@ typedef struct {
  *   bit 3:    if 1, then compression stream 3 should be reset;
  *   bits 7-4: if 1000 (0x08), then the compression type is "fill",
  *             if 1001 (0x09), then the compression type is "jpeg",
+ *             if 1001 (0x0A), then the compression type is "png",
  *             if 0xxx, then the compression type is "basic",
- *             values greater than 1001 are not valid.
+ *             values greater than 1010 are not valid.
  *
  * If the compression type is "basic", then bits 6..4 of the
  * compression control byte (those xxx in 0xxx) specify the following:
@@ -726,17 +731,17 @@ typedef struct {
  *   bit 6:     if 1, then a "filter id" byte is following this byte.
  *
  *-- The data that follows after the compression control byte described
- * above depends on the compression type ("fill", "jpeg" or "basic").
+ * above depends on the compression type ("fill", "jpeg", "png" or "basic").
  *
  *-- If the compression type is "fill", then the only pixel value follows, in
  * client pixel format (see NOTE 1). This value applies to all pixels of the
  * rectangle.
  *
- *-- If the compression type is "jpeg", the following data stream looks like
- * this:
+ *-- If the compression type is "jpeg" or "png", the following data stream
+ * looks like this:
  *
  *   1..3 bytes:  data size (N) in compact representation;
- *   N bytes:     JPEG image.
+ *   N bytes:     JPEG or PNG image.
  *
  * Data size is compactly represented in one, two or three bytes, according
  * to the following scheme:
@@ -817,7 +822,7 @@ typedef struct {
  *-- NOTE 2. The decoder must reset compression streams' states before
  * decoding the rectangle, if some of bits 0,1,2,3 in the compression control
  * byte are set to 1. Note that the decoder must reset zlib streams even if
- * the compression type is "fill" or "jpeg".
+ * the compression type is "fill", "jpeg" or "png".
  *
  *-- NOTE 3. The "gradient" filter and "jpeg" compression may be used only
  * when bits-per-pixel value is either 16 or 32, not 8.
@@ -831,7 +836,8 @@ typedef struct {
 #define rfbTightExplicitFilter         0x04
 #define rfbTightFill                   0x08
 #define rfbTightJpeg                   0x09
-#define rfbTightMaxSubencoding         0x09
+#define rfbTightPng                    0x0A
+#define rfbTightMaxSubencoding         0x0A
 
 /* Filters to improve compression efficiency */
 #define rfbTightFilterCopy             0x00