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+
+#include "../qcommon/q_shared.h"
+#include "../qcommon/qcommon.h"
+
+/*
+ * Include file for users of JPEG library.
+ * You will need to have included system headers that define at least
+ * the typedefs FILE and size_t before you can include jpeglib.h.
+ * (stdio.h is sufficient on ANSI-conforming systems.)
+ * You may also wish to include "jerror.h".
+ */
+
+#include "jpeglib.h"
+
+
+int LoadJPG( const char *filename, unsigned char **pic, int *width, int *height ) {
+ /* This struct contains the JPEG decompression parameters and pointers to
+ * working space (which is allocated as needed by the JPEG library).
+ */
+ struct jpeg_decompress_struct cinfo;
+ /* 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.
+ */
+ /* 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;
+ /* More stuff */
+ fileHandle_t infile; /* source file */
+ JSAMPARRAY buffer; /* Output row buffer */
+ int row_stride; /* physical row width in output buffer */
+ unsigned char *out;
+
+ /* 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.
+ */
+
+ FS_FOpenFileRead( filename, &infile, qfalse );
+ if (infile == 0) {
+ return 0;
+ }
+
+ /* Step 1: allocate and initialize JPEG decompression 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);
+
+ /* Now we can initialize the JPEG decompression object. */
+ jpeg_create_decompress(&cinfo);
+
+ /* Step 2: specify data source (eg, a file) */
+
+ jpeg_stdio_src(&cinfo, infile);
+
+ /* Step 3: read file parameters with jpeg_read_header() */
+
+ (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.
+ */
+
+ /* Step 4: set parameters for decompression */
+
+ /* 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 */
+
+ (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;
+
+ out = Z_Malloc(cinfo.output_width*cinfo.output_height*cinfo.output_components);
+
+ *pic = out;
+ *width = cinfo.output_width;
+ *height = cinfo.output_height;
+
+ /* Step 6: while (scan lines remain to be read) */
+ /* jpeg_read_scanlines(...); */
+
+ /* Here we use the library's state variable cinfo.output_scanline as the
+ * loop counter, so that we don't have to keep track ourselves.
+ */
+ while (cinfo.output_scanline < cinfo.output_height) {
+ /* jpeg_read_scanlines expects an array of pointers to scanlines.
+ * Here the array is only one element long, but you could ask for
+ * more than one scanline at a time if that's more convenient.
+ */
+ buffer = (JSAMPARRAY)out+(row_stride*cinfo.output_scanline);
+ (void) jpeg_read_scanlines(&cinfo, buffer, 1);
+ }
+
+ /* 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.
+ */
+
+ /* Step 8: Release JPEG decompression object */
+
+ /* This is an important step since it will release a good deal of memory. */
+ jpeg_destroy_decompress(&cinfo);
+
+ /* After finish_decompress, we can close the input file.
+ * Here we postpone it until after no more JPEG errors are possible,
+ * so as to simplify the setjmp error logic above. (Actually, I don't
+ * think that jpeg_destroy can do an error exit, but why assume anything...)
+ */
+ FS_FCloseFile(infile);
+
+ /* 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 1;
+}
+