JPEG decompression support
git-svn-id: svn://svn.code.sf.net/p/tigervnc/code/trunk@20 3789f03b-4d11-0410-bbf8-ca57d06f2519
diff --git a/rfb/TightDecoder.cxx b/rfb/TightDecoder.cxx
index 4677647..aa2c675 100644
--- a/rfb/TightDecoder.cxx
+++ b/rfb/TightDecoder.cxx
@@ -18,9 +18,25 @@
#include <rfb/CMsgReader.h>
#include <rfb/CMsgHandler.h>
#include <rfb/TightDecoder.h>
+#include <stdio.h> /* jpeglib.h needs FILE */
+#include <jpeglib.h>
using namespace rfb;
+#define RGB24_TO_PIXEL(bpp,r,g,b) \
+ ((((PIXEL_T)(r) & 0xFF) * myFormat.redMax + 127) / 255 \
+ << myFormat.redShift | \
+ (((PIXEL_T)(g) & 0xFF) * myFormat.greenMax + 127) / 255 \
+ << myFormat.greenShift | \
+ (((PIXEL_T)(b) & 0xFF) * myFormat.blueMax + 127) / 255 \
+ << myFormat.blueShift)
+
+#define TIGHT_MAX_WIDTH 2048
+
+static void JpegSetSrcManager(j_decompress_ptr cinfo, char *compressedData,
+ int compressedLen);
+static bool jpegError;
+
#define EXTRA_ARGS CMsgHandler* handler
#define FILL_RECT(r, p) handler->fillRect(r, p)
#define IMAGE_RECT(r, p) handler->imageRect(r, p)
@@ -50,7 +66,9 @@
void TightDecoder::readRect(const Rect& r, CMsgHandler* handler)
{
rdr::InStream* is = reader->getInStream();
- rdr::U8* buf = reader->getImageBuf(r.area());
+ /* Uncompressed RGB24 JPEG data, before translated, can be up to 3
+ times larger, if VNC bpp is 8. */
+ rdr::U8* buf = reader->getImageBuf(r.area()*3);
switch (reader->bpp()) {
case 8:
tightDecode8 (r, is, zis, (rdr::U8*) buf, handler); break;
@@ -60,3 +78,69 @@
tightDecode32(r, is, zis, (rdr::U32*)buf, handler); break;
}
}
+
+
+//
+// A "Source manager" for the JPEG library.
+//
+
+static struct jpeg_source_mgr jpegSrcManager;
+static JOCTET *jpegBufferPtr;
+static size_t jpegBufferLen;
+
+static void JpegInitSource(j_decompress_ptr cinfo);
+static boolean JpegFillInputBuffer(j_decompress_ptr cinfo);
+static void JpegSkipInputData(j_decompress_ptr cinfo, long num_bytes);
+static void JpegTermSource(j_decompress_ptr cinfo);
+
+static void
+JpegInitSource(j_decompress_ptr cinfo)
+{
+ jpegError = false;
+}
+
+static boolean
+JpegFillInputBuffer(j_decompress_ptr cinfo)
+{
+ jpegError = true;
+ jpegSrcManager.bytes_in_buffer = jpegBufferLen;
+ jpegSrcManager.next_input_byte = (JOCTET *)jpegBufferPtr;
+
+ return TRUE;
+}
+
+static void
+JpegSkipInputData(j_decompress_ptr cinfo, long num_bytes)
+{
+ if (num_bytes < 0 || (size_t)num_bytes > jpegSrcManager.bytes_in_buffer) {
+ jpegError = true;
+ jpegSrcManager.bytes_in_buffer = jpegBufferLen;
+ jpegSrcManager.next_input_byte = (JOCTET *)jpegBufferPtr;
+ } else {
+ jpegSrcManager.next_input_byte += (size_t) num_bytes;
+ jpegSrcManager.bytes_in_buffer -= (size_t) num_bytes;
+ }
+}
+
+static void
+JpegTermSource(j_decompress_ptr cinfo)
+{
+ /* No work necessary here. */
+}
+
+static void
+JpegSetSrcManager(j_decompress_ptr cinfo, char *compressedData, int compressedLen)
+{
+ jpegBufferPtr = (JOCTET *)compressedData;
+ jpegBufferLen = (size_t)compressedLen;
+
+ jpegSrcManager.init_source = JpegInitSource;
+ jpegSrcManager.fill_input_buffer = JpegFillInputBuffer;
+ jpegSrcManager.skip_input_data = JpegSkipInputData;
+ jpegSrcManager.resync_to_restart = jpeg_resync_to_restart;
+ jpegSrcManager.term_source = JpegTermSource;
+ jpegSrcManager.next_input_byte = jpegBufferPtr;
+ jpegSrcManager.bytes_in_buffer = jpegBufferLen;
+
+ cinfo->src = &jpegSrcManager;
+}