+// SavePCX:
+// Saves a PCX file into the wxImage object pointed by image.
+// Returns wxPCX_OK on success, or an error code otherwise
+// (see above for error codes). Will try to save as 8-bit
+// PCX if possible, and then fall back to 24-bit if there
+// are more than 256 different colours.
+//
+int SavePCX(wxImage *image, wxOutputStream& stream)
+{
+ unsigned char hdr[128]; // PCX header
+ unsigned char pal[768]; // palette for 8 bit images
+ unsigned char *p; // space to store one scanline
+ unsigned char *src; // pointer into wxImage data
+ unsigned int width, height; // size of the image
+ unsigned int bytesperline; // bytes per line (each plane)
+ unsigned char nplanes = 3; // number of planes
+ int format = wxPCX_24BIT; // image format (8 bit, 24 bit)
+ wxImageHistogram histogram; // image histogram
+ unsigned long key; // key in the hashtable
+ unsigned int i;
+
+ // See if we can save as 8 bit.
+
+ if (image->CountColours(256) <= 256)
+ {
+ image->ComputeHistogram(histogram);
+ format = wxPCX_8BIT;
+ nplanes = 1;
+ }
+
+ // Get image dimensions, calculate bytesperline (must be even,
+ // according to PCX specs) and allocate space for one complete
+ // scanline.
+
+ if (!image->Ok())
+ return wxPCX_INVFORMAT;
+
+ width = image->GetWidth();
+ height = image->GetHeight();
+ bytesperline = width;
+ if (bytesperline % 2)
+ bytesperline++;
+
+ if ((p = (unsigned char *) malloc(bytesperline * nplanes)) == NULL)
+ return wxPCX_MEMERR;
+
+ // Build header data and write it to the stream. Initially,
+ // set all bytes to zero (most values default to zero).
+
+ memset(hdr, 0, sizeof(hdr));
+
+ hdr[HDR_MANUFACTURER] = 10;
+ hdr[HDR_VERSION] = 5;
+ hdr[HDR_ENCODING] = 1;
+ hdr[HDR_NPLANES] = nplanes;
+ hdr[HDR_BITSPERPIXEL] = 8;
+ hdr[HDR_BYTESPERLINE] = (unsigned char)(bytesperline % 256);
+ hdr[HDR_BYTESPERLINE + 1] = (unsigned char)(bytesperline / 256);
+ hdr[HDR_XMAX] = (unsigned char)((width - 1) % 256);
+ hdr[HDR_XMAX + 1] = (unsigned char)((width - 1) / 256);
+ hdr[HDR_YMAX] = (unsigned char)((height - 1) % 256);
+ hdr[HDR_YMAX + 1] = (unsigned char)((height - 1) / 256);
+ hdr[HDR_PALETTEINFO] = 1;
+
+ stream.Write(hdr, 128);
+
+ // Encode image data line by line and write it to the stream
+
+ src = image->GetData();
+
+ for (; height; height--)
+ {
+ switch (format)
+ {
+ case wxPCX_8BIT:
+ {
+ unsigned char r, g, b;
+
+ for (i = 0; i < width; i++)
+ {
+ r = *(src++);
+ g = *(src++);
+ b = *(src++);
+ key = (r << 16) | (g << 8) | b;
+
+ p[i] = (unsigned char)histogram[key].index;
+ }
+ break;
+ }
+ case wxPCX_24BIT:
+ {
+ for (i = 0; i < width; i++)
+ {
+ p[i] = *(src++);
+ p[i + bytesperline] = *(src++);
+ p[i + 2 * bytesperline] = *(src++);
+ }
+ break;
+ }
+ }
+
+ RLEencode(p, bytesperline * nplanes, stream);
+ }
+
+ free(p);
+
+ // For 8 bit images, build the palette and write it to the stream:
+ if (format == wxPCX_8BIT)
+ {
+ // zero unused colours
+ memset(pal, 0, sizeof(pal));
+
+ unsigned long index;
+
+ for (wxImageHistogram::iterator entry = histogram.begin();
+ entry != histogram.end(); ++entry )
+ {
+ key = entry->first;
+ index = entry->second.index;
+ pal[3 * index] = (unsigned char)(key >> 16);
+ pal[3 * index + 1] = (unsigned char)(key >> 8);
+ pal[3 * index + 2] = (unsigned char)(key);
+ }
+
+ stream.PutC(12);
+ stream.Write(pal, 768);
+ }
+
+ return wxPCX_OK;
+}
projects / wxWidgets.git / blobdiff