Converting a grabbed image to JPEG is now done with the new function RgbToJpeg()

HISTORY

@@ -3963,7 +3963,7 @@ Video Disk Recorder Revision History
   commands may now be executed at any time, and the message will be displayed
   (no more "pending message").
 
-2005-12-28: Version 1.3.38
+2005-12-29: Version 1.3.38
 
 - Fixed handling second audio and Dolby Digital PIDs for encrypted channels
   (was broken in version 1.3.37).
@@ -4006,3 +4006,5 @@ Video Disk Recorder Revision History
   timer" menu for that timer.
 - Removing deleted recordings is now done in a separate thread.
 - Dropped the unused "stop recording on primary interface" stuff.
+- Converting a grabbed image to JPEG is now done with the new function
+  RgbToJpeg() (see tools.h).

dvbdevice.c

@@ -4,18 +4,11 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: dvbdevice.c 1.141 2005/12/28 12:28:05 kls Exp $
+ * $Id: dvbdevice.c 1.142 2005/12/29 11:24:02 kls Exp $
  */
 
 #include "dvbdevice.h"
 #include <errno.h>
-extern "C" {
-#ifdef boolean
-#define HAVE_BOOLEAN
-#endif
-#include <jpeglib.h>
-#undef boolean
-}
 #include <limits.h>
 #include <linux/videodev.h>
 #include <linux/dvb/audio.h>
@@ -539,27 +532,19 @@ bool cDvbDevice::GrabImage(const char *FileName, bool Jpeg, int Quality, int Siz
            if (f) {
               if (Jpeg) {
                  // write JPEG file:
-                 struct jpeg_compress_struct cinfo;
-                 struct jpeg_error_mgr jerr;
-                 cinfo.err = jpeg_std_error(&jerr);
-                 jpeg_create_compress(&cinfo);
-                 jpeg_stdio_dest(&cinfo, f);
-                 cinfo.image_width = vm.width;
-                 cinfo.image_height = vm.height;
-                 cinfo.input_components = 3;
-                 cinfo.in_color_space = JCS_RGB;
-
-                 jpeg_set_defaults(&cinfo);
-                 jpeg_set_quality(&cinfo, Quality, true);
-                 jpeg_start_compress(&cinfo, true);
-
-                 int rs = vm.width * 3;
-                 JSAMPROW rp[vm.height];
-                 for (int k = 0; k < vm.height; k++)
-                     rp[k] = &mem[rs * k];
-                 jpeg_write_scanlines(&cinfo, rp, vm.height);
-                 jpeg_finish_compress(&cinfo);
-                 jpeg_destroy_compress(&cinfo);
+                 int JpegImageSize;
+                 uchar *JpegImage = RgbToJpeg(mem, vm.width, vm.height, JpegImageSize, Quality);
+                 if (JpegImage) {
+                    if (fwrite(JpegImage, JpegImageSize, 1, f) != 1) {
+                       LOG_ERROR_STR(FileName);
+                       result |= 1;
+                       }
+                    delete JpegImage;
+                    }
+                 else {
+                    esyslog("ERROR: failed to convert image to JPEG");
+                    result |= 1;
+                    }
                  }
               else {
                  // write PNM file:

tools.c

@@ -4,13 +4,20 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: tools.c 1.105 2005/12/18 10:33:04 kls Exp $
+ * $Id: tools.c 1.106 2005/12/29 11:20:28 kls Exp $
  */
 
 #include "tools.h"
 #include <ctype.h>
 #include <dirent.h>
 #include <errno.h>
+extern "C" {
+#ifdef boolean
+#define HAVE_BOOLEAN
+#endif
+#include <jpeglib.h>
+#undef boolean
+}
 #include <stdarg.h>
 #include <stdlib.h>
 #include <sys/time.h>
@@ -651,6 +658,93 @@ cString TimeString(time_t t)
   return buf;
 }
 
+// --- RgbToJpeg -------------------------------------------------------------
+
+#define JPEGCOMPRESSMEM 500000
+
+struct tJpegCompressData {
+  int size;
+  uchar *mem;
+  };
+
+static void JpegCompressInitDestination(j_compress_ptr cinfo)
+{
+  tJpegCompressData *jcd = (tJpegCompressData *)cinfo->client_data;
+  if (jcd) {
+     cinfo->dest->free_in_buffer = jcd->size = JPEGCOMPRESSMEM;
+     cinfo->dest->next_output_byte = jcd->mem = MALLOC(uchar, jcd->size);
+     }
+}
+
+static boolean JpegCompressEmptyOutputBuffer(j_compress_ptr cinfo)
+{
+  tJpegCompressData *jcd = (tJpegCompressData *)cinfo->client_data;
+  if (jcd) {
+     int Used = jcd->size;
+     jcd->size += JPEGCOMPRESSMEM;
+     jcd->mem = (uchar *)realloc(jcd->mem, jcd->size);
+     if (jcd->mem) {
+        cinfo->dest->next_output_byte = jcd->mem + Used;
+        cinfo->dest->free_in_buffer = jcd->size - Used;
+        return TRUE;
+        }
+     }
+  return FALSE;
+}
+
+static void JpegCompressTermDestination(j_compress_ptr cinfo)
+{
+  tJpegCompressData *jcd = (tJpegCompressData *)cinfo->client_data;
+  if (jcd) {
+     int Used = cinfo->dest->next_output_byte - jcd->mem;
+     if (Used < jcd->size) {
+        jcd->size = Used;
+        jcd->mem = (uchar *)realloc(jcd->mem, jcd->size);
+        }
+     }
+}
+
+uchar *RgbToJpeg(uchar *Mem, int Width, int Height, int &Size, int Quality)
+{
+  if (Quality < 0)
+     Quality = 0;
+  else if (Quality > 100)
+     Quality = 100;
+  
+  jpeg_destination_mgr jdm;
+
+  jdm.init_destination = JpegCompressInitDestination;
+  jdm.empty_output_buffer = JpegCompressEmptyOutputBuffer;
+  jdm.term_destination = JpegCompressTermDestination;
+
+  struct jpeg_compress_struct cinfo;
+  struct jpeg_error_mgr jerr;
+  cinfo.err = jpeg_std_error(&jerr);
+  jpeg_create_compress(&cinfo);
+  cinfo.dest = &jdm;
+  tJpegCompressData jcd;
+  cinfo.client_data = &jcd;
+  cinfo.image_width = Width;
+  cinfo.image_height = Height;
+  cinfo.input_components = 3;
+  cinfo.in_color_space = JCS_RGB;
+
+  jpeg_set_defaults(&cinfo);
+  jpeg_set_quality(&cinfo, Quality, true);
+  jpeg_start_compress(&cinfo, true);
+
+  int rs = Width * 3;
+  JSAMPROW rp[Height];
+  for (int k = 0; k < Height; k++)
+      rp[k] = &Mem[rs * k];
+  jpeg_write_scanlines(&cinfo, rp, Height);
+  jpeg_finish_compress(&cinfo);
+  jpeg_destroy_compress(&cinfo);
+
+  Size = jcd.size;
+  return jcd.mem;
+}
+
 // --- cReadLine -------------------------------------------------------------
 
 cReadLine::cReadLine(void)

tools.h

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: tools.h 1.85 2005/12/17 11:09:37 kls Exp $
+ * $Id: tools.h 1.86 2005/12/29 11:09:43 kls Exp $
  */
 
 #ifndef __TOOLS_H
@@ -121,6 +121,15 @@ cString DayDateTime(time_t t = 0);
 cString TimeToString(time_t t);
 cString DateString(time_t t);
 cString TimeString(time_t t);
+uchar *RgbToJpeg(uchar *Mem, int Width, int Height, int &Size, int Quality = 100);
+    ///< Converts the given Memory to a JPEG image and returns a pointer
+    ///< to the resulting image. Mem must point to a data block of exactly
+    ///< (Width * Height) triplets of RGB image data bytes. Upon return, Size
+    ///< will hold the number of bytes of the resulting JPEG data.
+    ///< Quality can be in the range 0..100 and controls the quality of the
+    ///< resulting image, where 100 is "best". The caller takes ownership of
+    ///< the result and has to delete it once it is no longer needed.
+    ///< The result may be NULL in case of an error.
 
 class cTimeMs {
 private: