📄 ximajpg.cpp
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for(long x3=0,x4=0; x3<(long)info.dwEffWidth && x4<row_stride; x3+=3, x4+=4){ k=src[x4+3]; dst[x3] =(BYTE)((k * src[x4+2])/255); dst[x3+1]=(BYTE)((k * src[x4+1])/255); dst[x3+2]=(BYTE)((k * src[x4+0])/255); } } else { /* Assume put_scanline_someplace wants a pointer and sample count. */ iter.SetRow(buffer[0], row_stride); } iter.PrevRow(); } /* Step 7: Finish decompression */ (void) jpeg_finish_decompress(&cinfo); /* We can ignore the return value since suspension is not possible * with the stdio data source. */ //<DP> Step 7A: Swap red and blue components // not necessary if swapped red and blue definition in jmorecfg.h;ln322 <W. Morrison> if ((cinfo.num_components==3)&&(cinfo.quantize_colors==FALSE)){ BYTE* r0=GetBits(); for(long y=0;y<head.biHeight;y++){ if (info.nEscape) longjmp(jerr.setjmp_buffer, 1); // <vho> - cancel decoding RGBtoBGR(r0,3*head.biWidth); r0+=info.dwEffWidth; } } /* Step 8: Release JPEG decompression object */ /* This is an important step since it will release a good deal of memory. */ jpeg_destroy_decompress(&cinfo); /* At this point you may want to check to see whether any corrupt-data * warnings occurred (test whether jerr.pub.num_warnings is nonzero). */ /* And we're done! */ return true;}////////////////////////////////////////////////////////////////////////////////#if CXIMAGE_SUPPORT_ENCODE////////////////////////////////////////////////////////////////////////////////bool CxImageJPG::Encode(CxFile * hFile){ if (EncodeSafeCheck(hFile)) return false; if (head.biClrUsed!=0 && !IsGrayScale()){ strcpy(info.szLastError,"JPEG can save only RGB or GreyScale images"); return false; } // necessary for EXIF, and for roll backs long pos=hFile->Tell(); /* This struct contains the JPEG compression parameters and pointers to * working space (which is allocated as needed by the JPEG library). * It is possible to have several such structures, representing multiple * compression/decompression processes, in existence at once. We refer * to any one struct (and its associated working data) as a "JPEG object". */ struct jpeg_compress_struct cinfo; /* This struct represents a JPEG error handler. It is declared separately * because applications often want to supply a specialized error handler * (see the second half of this file for an example). But here we just * take the easy way out and use the standard error handler, which will * print a message on stderr and call exit() if compression fails. * Note that this struct must live as long as the main JPEG parameter * struct, to avoid dangling-pointer problems. */ //struct jpeg_error_mgr jerr; /* We use our private extension JPEG error handler. <CSC> */ struct jpg_error_mgr jerr; jerr.buffer=info.szLastError; /* More stuff */ int row_stride; /* physical row width in image buffer */ JSAMPARRAY buffer; /* Output row buffer */ /* Step 1: allocate and initialize JPEG compression object */ /* We have to set up the error handler first, in case the initialization * step fails. (Unlikely, but it could happen if you are out of memory.) * This routine fills in the contents of struct jerr, and returns jerr's * address which we place into the link field in cinfo. */ //cinfo.err = jpeg_std_error(&jerr); <CSC> /* We set up the normal JPEG error routines, then override error_exit. */ cinfo.err = jpeg_std_error(&jerr.pub); jerr.pub.error_exit = ima_jpeg_error_exit; /* Establish the setjmp return context for my_error_exit to use. */ if (setjmp(jerr.setjmp_buffer)) { /* If we get here, the JPEG code has signaled an error. * We need to clean up the JPEG object, close the input file, and return. */ strcpy(info.szLastError, jerr.buffer); //<CSC> jpeg_destroy_compress(&cinfo); return 0; } /* Now we can initialize the JPEG compression object. */ jpeg_create_compress(&cinfo); /* Step 2: specify data destination (eg, a file) */ /* Note: steps 2 and 3 can be done in either order. */ /* Here we use the library-supplied code to send compressed data to a * stdio stream. You can also write your own code to do something else. * VERY IMPORTANT: use "b" option to fopen() if you are on a machine that * requires it in order to write binary files. */ //jpeg_stdio_dest(&cinfo, outfile); CxFileJpg dest(hFile); cinfo.dest = &dest; /* Step 3: set parameters for compression */ /* First we supply a description of the input image. * Four fields of the cinfo struct must be filled in: */ cinfo.image_width = GetWidth(); // image width and height, in pixels cinfo.image_height = GetHeight(); if (IsGrayScale()){ cinfo.input_components = 1; // # of color components per pixel cinfo.in_color_space = JCS_GRAYSCALE; /* colorspace of input image */ } else { cinfo.input_components = 3; // # of color components per pixel cinfo.in_color_space = JCS_RGB; /* colorspace of input image */ } /* Now use the library's routine to set default compression parameters. * (You must set at least cinfo.in_color_space before calling this, * since the defaults depend on the source color space.) */ jpeg_set_defaults(&cinfo); /* Now you can set any non-default parameters you wish to. * Here we just illustrate the use of quality (quantization table) scaling: *///#ifdef C_ARITH_CODING_SUPPORTED if ((GetCodecOption(CXIMAGE_FORMAT_JPG) & ENCODE_ARITHMETIC) != 0) cinfo.arith_code = TRUE;//#endif//#ifdef ENTROPY_OPT_SUPPORTED if ((GetCodecOption(CXIMAGE_FORMAT_JPG) & ENCODE_OPTIMIZE) != 0) cinfo.optimize_coding = TRUE;//#endif if ((GetCodecOption(CXIMAGE_FORMAT_JPG) & ENCODE_GRAYSCALE) != 0) jpeg_set_colorspace(&cinfo, JCS_GRAYSCALE); if ((GetCodecOption(CXIMAGE_FORMAT_JPG) & ENCODE_SMOOTHING) != 0) cinfo.smoothing_factor = m_nSmoothing; jpeg_set_quality(&cinfo, GetJpegQuality(), (GetCodecOption(CXIMAGE_FORMAT_JPG) & ENCODE_BASELINE) != 0);//#ifdef C_PROGRESSIVE_SUPPORTED if ((GetCodecOption(CXIMAGE_FORMAT_JPG) & ENCODE_PROGRESSIVE) != 0) jpeg_simple_progression(&cinfo);//#endif#ifdef C_LOSSLESS_SUPPORTED if ((GetCodecOption(CXIMAGE_FORMAT_JPG) & ENCODE_LOSSLESS) != 0) jpeg_simple_lossless(&cinfo, m_nPredictor, m_nPointTransform);#endif cinfo.density_unit=1; cinfo.X_density=(unsigned short)GetXDPI(); cinfo.Y_density=(unsigned short)GetYDPI(); /* Step 4: Start compressor */ /* TRUE ensures that we will write a complete interchange-JPEG file. * Pass TRUE unless you are very sure of what you're doing. */ jpeg_start_compress(&cinfo, TRUE); /* Step 5: while (scan lines remain to be written) */ /* jpeg_write_scanlines(...); */ /* Here we use the library's state variable cinfo.next_scanline as the * loop counter, so that we don't have to keep track ourselves. * To keep things simple, we pass one scanline per call; you can pass * more if you wish, though. */ row_stride = info.dwEffWidth; /* JSAMPLEs per row in image_buffer */ //<DP> "8+row_stride" fix heap deallocation problem during debug??? buffer = (*cinfo.mem->alloc_sarray) ((j_common_ptr) &cinfo, JPOOL_IMAGE, 8+row_stride, 1); CImageIterator iter(this); iter.Upset(); while (cinfo.next_scanline < cinfo.image_height) { // info.nProgress = (long)(100*cinfo.next_scanline/cinfo.image_height); iter.GetRow(buffer[0], row_stride); // not necessary if swapped red and blue definition in jmorecfg.h;ln322 <W. Morrison> if (head.biClrUsed==0){ // swap R & B for RGB images RGBtoBGR(buffer[0], row_stride); // Lance : 1998/09/01 : Bug ID: EXP-2.1.1-9 } iter.PrevRow(); (void) jpeg_write_scanlines(&cinfo, buffer, 1); } /* Step 6: Finish compression */ jpeg_finish_compress(&cinfo); /* Step 7: release JPEG compression object */ /* This is an important step since it will release a good deal of memory. */ jpeg_destroy_compress(&cinfo);#if CXIMAGEJPG_SUPPORT_EXIF if (m_exif && m_exif->m_exifinfo->IsExif){ // discard useless sections (if any) read from original image m_exif->DiscardAllButExif(); // read new created image, to split the sections hFile->Seek(pos,SEEK_SET); m_exif->DecodeExif(hFile,EXIF_READ_IMAGE); // save back the image, adding EXIF section hFile->Seek(pos,SEEK_SET); m_exif->EncodeExif(hFile); }#endif /* And we're done! */ return true;}////////////////////////////////////////////////////////////////////////////////#endif // CXIMAGE_SUPPORT_ENCODE////////////////////////////////////////////////////////////////////////////////#endif // CXIMAGE_SUPPORT_JPG
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