XnView Software

Code: Select all

#define AR2_File_ProjectThumbnailImage	0x0ff003081
#define AR3_FilePreviewLargeOpaque		0x0ff003b00
#define PBX_File_CanvasColour			0x0ff003007
#define PBX_File_CanvasColourImage		0x0ff00300b


HBITMAP LoadThumbnail(LPCTSTR lpFileName)
{
	if (lpFileName == NULL) return NULL;
	FILE * cfFile = _wfsopen(lpFileName, L"rb", _SH_DENYNO); 
	CPNGReader pngReader;

	if (cfFile) {
		char csHeader[] = "Ambient Design Project file. ";
		char csVersion[] = "ArtRage 2";
		char csVersion1A[] = "ArtRage";
		char csVersion1B[] = "Paintbox";
		char buf[200];
		memset(buf, 0, sizeof(buf));
		fread(buf, sizeof(csHeader) - 1, 1, cfFile);
		if (strcmp(csHeader, buf) == 0) {
			fread(buf, 2, 1, cfFile);								// Spare byte.
			memset(buf, 0, sizeof(buf));
			
			fpos_t posVersion;
			fgetpos(cfFile, &posVersion);
			fread(buf, sizeof(csVersion) - 1, 1, cfFile);
			UINT nVersion = 0;
			if (strcmp(csVersion, buf) == 0) {
				nVersion = 2;
				posVersion += sizeof(csVersion);													// Advance past the ArtRage 2 version string
			}
			else if (strncmp(csVersion1A, buf, sizeof(csVersion1A) - 1) == 0) {						// Version 1 string "ArtRage"
				nVersion = 1;
				posVersion += sizeof(csVersion1A);													// Advance past the ArtRage 2 version string
			}
			else if (strncmp(csVersion1B, buf, sizeof(csVersion1B) - 1) == 0) {						// Version 1 string "Paintbox"
				nVersion = 1;
				posVersion += sizeof(csVersion1B);													// Advance past the ArtRage 2 version string
			}

			if (nVersion > 0) {																		// We found a version string
				_fseeki64(cfFile, posVersion + 5, SEEK_SET);										// Move to next block (allowing for already-read data

				// Parse blocks, looking for Thumbnail block
				fpos_t pos;
				fgetpos(cfFile, &pos);
				UINT64 nFileSize = _filelengthi64(_fileno(cfFile));
				UINT64 nFilePos = pos; 
				UINT nBlockID = 0;
				UINT64 nBlockSize = 0;
				while (nFilePos < nFileSize - 4) {															// Read in the project information.
					
					// Find and process the block.
					fread(&nBlockID, sizeof(UINT), 1, cfFile);
					fread(&nBlockSize, sizeof(UINT64), 1, cfFile);
					if (nBlockSize <1> nFileSize) break;														// 'nother silly block.

					// Check for paper-colour block
					if (nVersion == 1 && nBlockID == PBX_File_CanvasColour) {								// Found the paper-colour block
						UINT32 pxColour;
						fread(&pxColour, sizeof(pxColour), 1, cfFile);										// Read in the colour
						pngReader.SetPaperColour(pxColour);													// Set the paper colour.
					}

					// Look for Thumbnail block.
					else if ((nVersion == 2 && (nBlockID == AR2_File_ProjectThumbnailImage					// Thumbnail block found.
												|| nBlockID == AR3_FilePreviewLargeOpaque))					// Full-sized preview block found.
						||(nVersion == 1 && nBlockID == PBX_File_CanvasColourImage)) {						// Colour Map from ArtRage 1 found.
						// Read in the PNG image.
						char * pMem = NULL;
						
						// cfFile is now pointing to a PNG inlined into the project file.  Use something to read PNG from this point.
						if (pngReader.ReadImage(cfFile, pMem, nWidth, nHeight)) {
							if (nWidth <= 8 || nHeight <8> 100000 || nHeight > 100000) break;	// Cabbage out for silly values.

							// *****  Do something with the image data 

						}
						if (pMem) free(pMem);
						break;																			// Dont need to search the rest of the project file.
					}
					
					// Ensure the file is in the correct position for the next block.  Unknown blocks are ignored.
					_fseeki64(cfFile, nFilePos + nBlockSize + 12, SEEK_SET);							// Move to next block (allowing for already-read data
					fgetpos(cfFile, &pos);
					nFilePos = pos;																		// Get the current file location.
				}
			}
		}
		fclose(cfFile);
	}
	return NULL; 
}