+ /* We use our private extension JPEG error handler.
+ * Note that this struct must live as long as the main JPEG parameter
+ * struct, to avoid dangling-pointer problems.
+ */
+ struct my_error_mgr jerr;
+ /* More stuff */
+
+ JSAMPARRAY buffer;/* Output row buffer */
+
+ // rappel :
+ // ------
+ // typedef unsigned char JSAMPLE;
+ // typedef JSAMPLE FAR *JSAMPROW;/* ptr to one image row of pixel samples. */
+ // typedef JSAMPROW *JSAMPARRAY;/* ptr to some rows (a 2-D sample array) */
+ // typedef JSAMPARRAY *JSAMPIMAGE;/* a 3-D sample array: top index is color */
+
+ int row_stride;/* physical row width in output buffer */
+#ifdef GDCM_JPG_DEBUG
+ printf("entree dans gdcmFile::gdcm_read_JPEG_file12, depuis gdcmJpeg\n");
+#endif //GDCM_JPG_DEBUG
+
+ /* In this example we want to open the input file before doing anything else,
+ * so that the setjmp() error recovery below can assume the file is open.
+ * VERY IMPORTANT: use "b" option to fopen() if you are on a machine that
+ * requires it in order to read binary files.
+ */
+
+ /* Step 1: allocate and initialize JPEG decompression object */
+#ifdef GDCM_JPG_DEBUG
+ printf("Entree Step 1\n");
+#endif //GDCM_JPG_DEBUG
+
+ /* We set up the normal JPEG error routines, then override error_exit. */
+
+ cinfo.err = jpeg_std_error(&jerr.pub);
+ jerr.pub.error_exit = my_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.
+ */
+ jpeg_destroy_decompress(&cinfo);
+ return(false);
+ }
+
+ /* Now we can initialize the JPEG decompression object. */
+ jpeg_create_decompress(&cinfo);
+
+ /* Step 2: specify data source (eg, a file) */
+#ifdef GDCM_JPG_DEBUG
+ printf("Entree Step 2\n");
+#endif //GDCM_JPG_DEBUG
+ jpeg_stdio_src(&cinfo, fp);
+
+ /* Step 3: read file parameters with jpeg_read_header() */
+#ifdef GDCM_JPG_DEBUG
+ printf("Entree Step 3\n");
+#endif //GDCM_JPG_DEBUG
+ (void) jpeg_read_header(&cinfo, TRUE);
+
+ /* We can ignore the return value from jpeg_read_header since
+ * (a) suspension is not possible with the stdio data source, and
+ * (b) we passed TRUE to reject a tables-only JPEG file as an error.
+ * See libjpeg.doc for more info.
+ */
+
+#ifdef GDCM_JPG_DEBUG
+ printf("--------------Header contents :----------------\n");
+ printf("image_width %d image_height %d\n",
+ cinfo.image_width , cinfo.image_height);
+ printf("bits of precision in image data %d \n",
+ cinfo.output_components);
+ printf("nb of color components returned %d \n",
+ cinfo.data_precision);
+#endif //GDCM_JPG_DEBUG
+
+
+ /*
+ * JDIMENSION image_width; // input image width
+ * JDIMENSION image_height; // input image height
+ * int output_components; // # of color components returned
+ * J_COLOR_SPACE in_color_space; // colorspace of input image
+ * double input_gamma; // image gamma of input image
+ * int data_precision; // bits of precision in image data
+ */
+
+ /* Step 4: set parameters for decompression */
+#ifdef GDCM_JPG_DEBUG
+ printf("Entree Step 4\n");
+#endif //GDCM_JPG_DEBUG
+
+ /* In this example, we don't need to change any of the defaults set by
+ * jpeg_read_header(), so we do nothing here.
+ */
+
+ /* Step 5: Start decompressor */
+#ifdef GDCM_JPG_DEBUG
+ printf("Entree Step 5\n");
+#endif //GDCM_JPG_DEBUG
+
+ (void) jpeg_start_decompress(&cinfo);
+ /* We can ignore the return value since suspension is not possible
+ * with the stdio data source.
+ */
+
+ /* We may need to do some setup of our own at this point before reading
+ * the data. After jpeg_start_decompress() we have the correct scaled
+ * output image dimensions available, as well as the output colormap
+ * if we asked for color quantization.
+ * In this example, we need to make an output work buffer of the right size.
+ */
+
+ /* JSAMPLEs per row in output buffer */
+ row_stride = cinfo.output_width * cinfo.output_components;